The Boundaries of the Region Are Margo Supraorbitalis, Linea Temporalis Superior, Linea Nuchae Superior Till Protuberantia Occipitalis Externa

Home , Deep parotid lymph nodes, Jugular venous arch, Maxillary veins, Occipital sinus

Topographical anatomy & operative surgery of the head. Topographical pecularities of regions of the head and its practical importance. Main principles of surgical treatments

The boundaries and divisions. The border between the head and a neck carried out (conditionally) to the inferior margin of mandible, angle of mandible, posterior margin of the vertical process of the mandible; the anterior and posterior edges of the mastoid process, superior nuchal line (linea nuchae superior), external occipital protuberance (protuberantia occipitalis externa). Then it passes symmetrically to the opposite side. On the head distinguish cerebral and facial departments, according to the cerebral and facial skull. The border between these departments passes by supraorbital margin, superior margin of the zygomatic arch to the porus acusticus externus. All that is down and anterior to this border belongs to the facial department, which is upward and backward, refers to the cerebral department. The cerebral department is divided into calvaria (fornix cranii) and bases of skull (basis cranii). The boundary between the base of scull and calvaria is mainly passes by the horizontal plane which joins the nasion to the inion (an imaginary line that passes along the supraorbital margin - margo supraorbitalis, superior margin of the zygomatic arch - arcus zigomaticus, base of the mastoid process - processus mastoideus, upper nuchal line - linea nuchae superior to inion). The parts of the skull located above this plane belong to the calvaria; located below - to the base of skull. Calvaria areas. 1) fronto-parietal-occipital region - regio frontoparietooccipitalis; 2) Temporal region - regio temporalis.

Fronto-parieto-occipital region (regio fronto-parieto-occipitalis) The boundaries of the region are margo supraorbitalis, linea temporalis superior, linea nuchae superior till protuberantia occipitalis externa. Scalp The scalp covers the calvaria, extending from the superior nuchal lines on the occipital bone to the supraorbital margins of the frontal bone. The scalp consists of five layers of soft tissues, the first three of which are connected intimately and move as a unit. Each letter of the word scalp serves as a memory key for its layers: skin, connective tissue, aponeurosis epicranialis, loose connective tissue, and pericranium. I The skin, thick especially in the occipital region, contains many sweat and sebaceous glands and hair follicles; it has an abundant arterial supply and good venous and lymphatic drainage. The skin is fixed to the aponeurosis by dense strands of fibrous tissue which traverse the subcutaneous tissue and split it into a number of separate pockets filled with fat. II The connective tissue is a thick, richly vascularized, subcutaneous layer which is well supplied with nerves. The connective tissue includes five neuro-vascular bunches and a separate nerve Location of the neuro-vascular bunches 1. a.v.n. supratrochlearis ( frontalis ) 2. a.v.n. supraorbitalis Arteries are terminal branches of ophthalmic artery, a branch of internal carotid artery; veins begin from the forehead and descend to unite at the medial angle of the eye to form the facial vein. Veins have connection with ophthalmic vein, which drains into sinus cavernosus. Nerves are the major cutaneous branches of the ophthalmic nerve (first branch of trigeminal nerve). 3. a.v. temporalis superficialis and n.auriculo-temporalis. Artery is smaller terminal branch of external carotid artery. The superficial temporal artery emerges on the face between the temporomandibular joint and the ear and ends in the scalp by dividing into frontal and parietal branches, the vein drains the forehead and scalp and receives tributaries from the veins of the temple and face. Near the auricle, the superficial temporal vein enters the parotid gland. The retromandibular vein, formed by the union of the superficial temporal and maxillary veins, descends within the parotid gland, superficial to the external carotid artery and deep to the facial nerve. The retromandibular vein is divided into an anterior branch that unites with the facial vein and a posterior 1 branch that joins the posterior auricular vein to form the external jugular vein. The nerve is major cutaneous branch of the mandibular nerve, which is the third branch of trigeminal nerve. 4. a.v.n. auricularis posterior. Artery is branch of external carotid artery; auricular posterior nerve is branch of facial nerve. 5. a.v. occipitalis and n.occipitalis major. Artery is a branch of external carotid artery. Vein forms external jugular vein with v. auricularis posterior. Nerve is branch of the second cervical nerve (posterior root ). 6.n. occipitalis minor is situated between the fourth and fifth bunches. It is a branch of cervical plexus. These arteries and veins of the scalp make anastomoses freely with each other and with those of the opposite side. Because of this, wounds of the scalp bleed profusely, but heal rapidly. III The aponeurosis epicranialis is a strong stringy sheet that covers the superior aspect of the calvaria; the aponeurosis is the membranous tendon of the fleshy bellies of the occipitalis and frontalis muscles (whereas the frontalis pulls the scalp anteriorly, wrinkles the forehead, and elevates the eyeblayerss, the occipitalis pulls the scalp posteriorly and wrinkles the skin on the posterior aspect of the neck). The aponeurosis consists of two layers. The deep layer attaches to the borders of the region and the superficial one continues to the neibouring regions as superficial fascia. IV The loose connective tissue is somewhat like a sponge because it has many potential spaces that may distend with fluid that results from injury or infection; this layer allows free movement of the scalp proper (first three layers, skin, connective tissue, and epicranial aponeurosis). V The pericranium, a dense layer of connective tissue, is the periosteum of the calvaria; it attaches firmly to the cranial bones, but the pericranium can be stripped fairly easily from the cranial bones of living persons, except where it is continuous with the fibrous tissue in the cranial sutures. VI The subperiostal connective tissue is situated between the pericranium and the bone. VII The bones of the head consist of three layers. The names of the external and internal layers are lamina compacta externa et interna (or vitrea) because it can be broken very easily. The name of the middle layer is lamina diploe, which contains diploic veins. VIII The cranial dura mater consists of two layers. Dural venous sinuses are situated between two layers of dura mater.

Projections of the main neurovascular bundles of the fronto-parietal-occipital region.

1. A.v. n. supratrochlearis - projected on the crosspoint between vertical line drawn through the medial angle of the orbit and supraorbital line. 2. A. v. n. supraorbitalis - projected on the border between middle and medial thirds of supraorbital line. 3. A. v. temporalis superficialis, n. auriculotemporalis - projected one transverse finger in front to the tragus of the ear on the zygomatic arch. 4. A. v. n. auricularis posterior - projected by the middle of the distancesbetween the external auditory meatus and the tip of the mastoid.process 5. A. v. occipitalis, n. occipitalis major - projected on the midpoint of the distances between the tip of the mastoid process and inion. 6. N. occipitalis minor - is projected on the tip of the mastoid process

The Peculiarities of Fatty Tissue in Fronto-parieto-occipital Region Blood or pus can gather in those layers, where we have loose connective tissue. In this region there are three layers of this kind and in each of them haematoma or abscess has peculiarities: a) Subcutaneous fatty tissue- Haematomae which are located in this layer are blocked, as they appear in separate pockets of subcutaneous tissue (between dense fibrous septa connecting the skin with aponeurosis). These haematomae appear just in the region of the injury by oedema of the skin as a “lump” Frontal region is an exception, where subcutaneous tissue has connection with subcutaneous tissue of the superior eyelid. Here haematoma and oedema can spread easily. b) Subaponeurotic loose connective tissue- Haematomae and abscesses of this layer can spread all over the region, but they cannot spread out of its boundaries, as the deep layer of the aponeurosis is attached to the boundaries of the region. An exception is again frontal region, where there is connection with the loose 2 connective tissue of the orbits. Consequently, a black eye can result from an injury to the scalp (a symptom of the “glasses”) c) Subperiostal connective tissue- Haematomae of this layer can spread inside the boundaries of a bone, as periosteum is attached to the bones in the region of the sutures.

The Peculiarities of Blood Supply in Fronto-parieto-occipital Region Peculiarities of Arterial Supply 1. The main vessels of this region are in subcutaneous fatty tissue and extend to the bregma from every side. Because of this superficial position they can be damaged very easily. 2. The vessels are fixed by their adventitia to the dense strands of the connective tissue and so remain retracted when they are injured. 3. The vessels make anastomoses freely with each other and with those of the opposite side. That’s why bleeding is from the both sides of injured vessel. So the scalp wounds bleed profusely, but heal rapidly. 4. Here we have anastomoses between the branches of internal and external carotid arteries.

Peculiarities of the Venous Supply The venous supply of this region consists of three levels: 1. Veins which are located in subcutaneous tissue. 2. Diploic veins. 3. Dural venous sinuses. They are connected through the emissary veins. Emissary veins don’t have any valves and blood can pass in two directions. The permanent emissary veins are: - Parietal (in fronto-parieto-occipital region, single) - Mastoid (in mastoid region, double) - Occipital (in fronto-parieto-occipital region, double) If the patient has an inflammation of scalp in area of emissary veins the infection may spread into the cranium and if the patient has a wound of the scalp in area of emissary veins profuse venous bleeding may occur. It is a negative feature. But when the patient has high intracranial pressure we can reduce it by washing the head with hot water. If the patient has headaches due to high intracranial pressure, this procedure will help him.

THE DURA MATER The cerebral dura mater (dura mater encephali), or pachymeninx, a thick whitish connective-tissue membrane, it is a outermost tunic of brain. Its external surface is in direct contact with the cranial bones for which it serves as the periosteum; this is the main feature distinguishing it from the spinal dura mater. The inner surface facing the brain is lined with endothelium and is therefore smooth and shiny. Between it and the cerebral arachnoid mater is a narrow slit-like subdural space (cavum subdurale) filled with a small amount of fluid. At places the dura mater is separated into two layers, namely, in the region of the venous sinuses (see below) and in the region of the fossa at the apex of the pyramid of the temporal bone (to form the cavum trigeminale) where the trigeminal nerve ganglion is located. The dura mater gives off several processes from its inner surface, which penetrate between the parts of the brain and separate one part from another. The falx cerebri, a large sickle-shaped process, lies sagittally between both cerebral hemispheres. On the midline of the calvaria it is attached to the margins of the sulcus sinus sagittalis superioris, its anterior narrow end grows into the crista galli, while the wide posterior end blends with the superior surface of the tentorium cerebelli. The tentorium cerebelli is a horizontally stretched plate slightly convex upward like a roof with two sloping surfaces. It is attached to the margins of the sinus sulcus transversi of the occipital bone and along the anterior side of the pyramid of the temporal bone on both sides, up to the posterior clinoid process of the sphenoid bone. The tentorium cerebelli separates the cerebral occipital lobes from the cerebellum lying below them. The falx cerebelli, a small sickle-shaped process, lies, like the falx cerebri, on the midline along the crista occipitalis interna and stretches to the foramen magnum whose sides it embraces with two limbs; this small process projects into the posterior cerebellar notch. 3

The diaphragma sellae is a plate forming the roof over the fossa in which the hypophysis cerebri is lodged on the floor of the sella turcica. The dura mater contains several reservoirs collecting blood from the brain; these are the sinuses at the dura mater (sinus durae materis). The sinuses are venous canals (triangular on transverse section) devoid of valves and located in the thickness of the dura mater at the attachment of its processes to the skull; they differ from veins in the structure of their walls which are composed of tightly stretched layers of the dura mater and consequently do not collapse when cut and gape on being injured. The inflexibility of the walls of the venous sinuses provides free drainage of venous blood in changes of intracranial pressure; this is important for uninterrupted activity of the brain, which explains why such venous sinuses are present only in the skull. The sinuses are as follows. - The transverse sinus (sinus transversus), the largest and widest sinus which runs along the posterior margin of the tentorium cerebelli in the sulcus sinus transversi of the occipital bone. From here it descends into the sulcus sinus sigmoidei under the name of the sigmoid sinus (sinus sigmoideus), and at the jugular foramen is continuous with the orifice of the internal jugular vein. As a result, the transverse and sigmoid sinuses form the main receptacle for all the venous blood of the cranial cavity. All the other sinuses drain into it either directly or indirectly. It is projected by direction of the superior nucal line. Sigmoid sinus projected by direction of posterior margin of the mastoid process. The following sinuses drain directly into transverse sinus: - The superior sagittal sinus (sinus sagittalis superior) runs on the upper margin of falx cerebri for the whole length of sulcus sinus sagittalis superioris from crista galli to the internal occipital protuberance. It is projected by the line, which connect nasion with inion. -The inferior sagittal sinus (sinus sagittalis superior) runs on the lower margin of falx cerebri. It is projected by direction of the superior temporal line. -The occipital sinus (sinus occipitalis) is a continuation, as it were, of the superior sagittal sinus along the attachment of falx cerebelli to the internal occipital crest and then (after bifurcating) along both margins of the foramen magnum of the occipital bone. -The straight sinus (sinus rectus) runs on the line of attachment of falx cerebri to tentorium cerebelli. It receives anteriorly the inferior sagittal sinus (sinus sagittalis inferior) stretching on the free lower margin of falx cerebri and vena cerebri magna (Galeni) carrying blood from the deep parts of the brain. At the confluence of these sinuses (transverse, superior sagittal, straight, and occipital) a common expansion forms; it is called the confluence of the sinuses (confluens sinuum), or torcula herophili. -The cavernous sinus (sinus cavernosus) is located on the base of the skull lateral to the sella turcica. It has the apperance of either a venous plexus or a wide lacuna surrounding the internal carotid artery. It is connected with a similar sinus on the other side by means of two transverse communications, intercavernous sinuses (sinus intercavernosus), passing in front of and behind the hypophyseal fossa as a consequence of which a venous circle forms in the region of the sella turcica. According to certain data, the cavernous sinus is an intricate anatomical complex whose components, in addition to the sinus itself, are the internal carotid artery, the nerves and the connective tissue surrounding them. All these structures compose, as it were, a special instrument which plays an important role in regulation of the intracranial flow of venous blood. The cavernous sinus receives anteriorly the superior ophthalmic vein passing through the superior orbital fissure, as well as the inferior end of the sphenoparietal sinus (sinus sphenoparietalis) running on the margin of the ala parva. The cavernous sinus is drained of blood by two sinuses located behind it, namely the inferior and superior petrosal sinuses (sirtus petrosus superior and inferior) located in the superior and inferior petrosal sulci. Both inferior petrosal sinuses communicate by means of several venous canals which lie within the dura mater on the basal part of the occipital bone and are united under the term plexus basilaris. This plexus is connected with the venous plexuses of the vertebral canal, into which blood from the cranial cavity flows. Blood drains from the sinuses mainly into the internal jugular veins, but the sinuses are also connected with the veins of the outer surface of the skull through emissary veins (venae emissariae) transmitted through openings in the skull bones (foramen parietale, foramen mastoideum, canalis condylaris). Emissary veins are parietal, mastoid and occipital. Unpaired parietal vein connects with superior saggital sinus, mastoid veins with 4 sigmoid sinus, occipital veins with transverse sinus. Small veins leaving the skull together with nerves through foramen ovale, foramen rotundum and canalis hypoglossi play a similar role. The diploic veins and the veins of the spongy substance of the cranial bones also drain into the sinuses of the dura mater, while their other end may be connected with the veins on the external surface of the head. The diploic veins (venae diploicae) are canals anastomosing with one another and lined by a layer of endothelium; they pass in the spongy substance of the flat cranial bones.

Temporal Region (regio temporalis)

Boundaries of temporal region: • Superiorly and posteriorly–superior temporal line. • Anteriorly –superior, lateral margin of the orbit. • Inferiorly – superior border of the zygomatic arch. Layers 1. The skin- posteriorly and superiorly is thick and hairy. Anteriorly and inferiorly – thin, movable, without hair. 2. The subcutaneous fatty tissue is not well developed. 3. The superficial fascia divides the fatty tissue into two layers. A.v. temporalis superficialis and n. auriculotemporalis are situated in the deep layer. This bunch passes all over the region and is divided into two branches: frontal and parietal. One can palpate the pulsation of this artery if he (she) puts a finger on the zygomatic arch 1cm anterior to the tragus. The auriculotemporal nerve is major cutaneous branch of the mandibular nerve, which is the third branch of trigeminal nerve. The sensory nerve supply of the skin is from n. zygomatico-temporalis (maxillary division of n. trigeminus). In this layer temporal and zygomatic branches of n. facialis are situated. 4. Temporal fascia (aponeurosis) starts from linea temporalis superior. It covers the temporal muscle. Near zygomatic arch it splits into superficial and deep layers, which attach to the outer and inner borders of zygomatic arch. Fatty tissue and a.v. temporalis media (branch of a.v. temporalis superficialis) are situated between these two layers. 5. Subaponeurotic fatty tissue connects this region under zygomatic arch with infratemporal fossa in the deep facial region. So infection can spread from one region to another. Subaponeurotic fatty tissue, m. temporalis and a.v.n.temporalis profundus are situated in the temporal fossa. 6. M. temporalis begins from the linea temporalis inferior and its tendon is attached to the processus coronoideus mandibulae under the zygomatic arch. On the inner aspect of the muscle a.v.n. temporalis profundus are situated (artery is from a. maxillaris, nerve- from n. mandibularis). 7. Temporal bone (squama) – thin, diploetic layer is non well developed, the periosteum is attached to the bone, the subperiostal fat is absent, bone is fragile. a. meningea media is situated on the inner surface of the bone or in the canal inside of bone. The injury to this artery can cause epidural haematoma.

Mastoid Region (regio mastoidea)

Boundaries of this region are: • Superiorly is the line, which is the continuation of zygomatic arch. • Anteriorly and posteriorly are the margins of mastoid process.

Layers: 1. The skin is thin, without hair, not movable. 2. The subcutaneous fatty tissue includes: a.v.n. auricularis posterior (artery is a branch of external carotid artery, vein with posterior branch of retromandibular vein and occipital vein forms the external jugular vein, nerve is branch of facial nerve), n.auricularis magnus and n.occipitalis minor are branches of plexus cervicalis. 5

3. The superficial fascia. 4. The proper deep fascia. 5. Mastoid process of the temporal bone is covered with periosteum. Crista mastoidea is divided the region into anterior and posterior parts. In the posterior part which is called tuberositas mastoidea the tendons of the muscles are attached here – m.sternocleidomastoideus, m.splenius coli, the posterior belly of digastrics muscle. On the anterior surface of mastoid process the periosteum is not strongly attached to the bone and the trepanation triangle is described by Shipoult. The boundaries of this triangle are: anteriorly - suprameatic spine or the posterior margin of the auricle, superiorly it coincides with the superior boundary of this region, posteriorly- crista mastoidea. Mastoid air-cells (cellulae mastoideae) are situated in the thickness of the bone inside the boundaries of above mentioned triangle. The largest cellula of the mastoid process, antrum mastoideum, is connected with cavum tympany through aditus ad antrum. Cavum tympany is connected with nasopharynx through the tuba auditiva. By this way infection can spread from the pharynx to the cavum tympany and antrum mastoideum and acute supurative mastoiditis may develop. During antrotomy we can hurt the following structures if we go out of the boundaries of trepanation triangle: superiorly – brain in the middle cranial fossa, anteroirly – facial nerve in its canal, posteroirly – sigmoid sinus. The auditive tube is shorter, wider and has a horizontal direction for children, for adults it has an oblique, vertical position. This has a greater importance for spreading infection from the nasophanynx to the middle ear.

Krenlein’s Diagram This diagram is used for projecting important structures in the cranial cavity and is necessary for exact access to them. The following lines are used for making the diagram: • linea sagittalis -- connects the midpoint of glabella(nasion) with protuberantia occipitalis externa (inion). • linea auriculoorbitalis –inferior horizontal line -- connects margo infraorbitalis with margo superior of the porus acusticus externus. • linea supraorbitalis- superior horizontal line -- passes parallelly to first one through margo supraorbitalis. Three vertical lines are made also: 1. linea zygomatica-anterior vertical line -- passes perpendicularly to horizontal lines through the midpoint of the zygomatic arch. 2. linea articulationes-middle vertical line -- passes parallelly to first one through processus articulationes os mandibulae. 3. linea mastoidea –posterior vertical line -- is parallel to first and second and passes through the posterior margin of the base of mastoid process. By this diagram a. meningea media is projected. • Main trunk is projected in the crossing point of first(anterior) vertical line with first(inferior) horizontal line. • Anterior branch (r. anterior s.frontalis) is projected in the cross-point of the first vertical line with second (superior) horizontal line. • Posterior branch (r. posterior s. parietalis)- in the cross-point of the third(posterior) vertical and superior horizontal lines. Sulcus centralis (Rolandi) is projected by a line connecting the cross-points of the anterior vertical line with superior horizontal line and posterior vertical line with the sagittal one. The length of the line is measured by a part of the line between the middle and the posterior vertical lines. Sulcus lateralis (Silvii) is projected by the bisector of the angle between superior horizontal and the projectional line of the central groove (sulcus centralis) of the brain.

Facial Region Facial region is subdivided into medial and lateral parts. Medial region is included orbits, nasal part, oral part and mental part. The lateral region consists from deep and superficial regions and the last one includes the buccal and parotideomasseteric regions.

Lateral Facial Region (regiofacialislateralis) Boundaries of this region are: Superiorly - margoinfraorbitalis and arcuszygomaticus. Inferiorly - inferior border of the mandible. Anteriorly - plicanasobuccalis and buccolabialis. Posteriorly - posterior border of the vertical process of the mandible (or imaginary line between the angle of the mandible and apex of the mastoid process because of situation here of parotid gland). This region is divided into superficial and deep regions. The superficial region is subdivided into regiobuccalis and regioparotideo-masseterica by the anterior margin of the masseter muscle.

Buccal Region (regiobuccalis)

1. The skin is thin and elastic, without hair. It contains many sweat and sebaceous glands. The elasticity of this region is used in reconstruction surgery practice for liquidation of local skin defects. Skin is firmly attached to the well developed fatty tissue and facial expression muscles. In men hair is present in the lower part of the region. Skin is innervated by the branches of the trigeminal nerve (n. trigeminus). 2. The subcutaneous fatty tissue is well developed and contains the arteriovenous bunches. Superficial fascia subdivides the subcutaneous fat into two layers: superficial, which is intimately fused with the skin, and deep one. Corpus adiposumbuccae or Bichat’s adipose body is located in this layer and is well developed for women and kids. It is surrounded by the capsule, which is formed by superficial fascia, that’s why can be separated from other subcutaneous fatty tissue, masseteric and facial expression muscles. It has three processes: processusorbitalis, processus temporalis and processuspterygopalatinus. - temporalprocess - passes under the zygomatic arch into the temporal fossa (along the lateral wall of the orbit); - orbitalprocess- passes under the zygomatic arch into the infratemporalfossa and then through the lower orbital fissure(fissuraorbitalis inferior) into the orbit;

- pterygopalatine process- passes under the zygomatic arch into the fossa pterygopalatina and can penetrate through the medial surface of the lowerorbital fissure and then upper orbital fissure inside of the cranial cavity towards the cavernous sinus. Means that such way purulent process can spread to the sinus cavernosusin case of phlegmone of the facial region, when venous anastomoses aren’t involved in the process.

In the deep layer of the subcutaneous fatty tissue together with vessels and nerves also aredescribed the facial expression muscles with two layers: superficial and deep. In superficial layer are situated m.orbicularis oculi,under it mm. zygomatici major et minor, m.levatorlabii superiorand etc.(in the anatomical nomenclature up to 20 muscles). Superficial group offacial expression muscles starts from the bones of the facial skull and is finished in the thickness of the skin, being firmly fused with the subcutaneous fatty tissue. In the buccal region muscles are at different levels, they are separated into interfascial layers by the connective tissue. Constriction of these muscles (which are responsible for the expression of the face)provides themovability of the skin andformation offolds and wrinkles. In deep layerunder the proper fascia(fascia bucco-pharyngea) is present m.buccinator, whichis flat, has quadrangular form and attaches to the anterior aspect of themaxilla and with one end and afterwards muscular fiberspass horizontally towards the medial angle of mouth, and fusedwith another interlace with m.orbicularisoris. On the external aspect of the buccal muscle are present buccal nerve and artery (n .buccalis, a.buccinatoria), which accompany buccal lymphatic nodes. On the inner surface muscle is covered by mucous membrane (wall of the oral cavity).Duct of parotid gland passes through the corpus adiposumbuccae, fascia bucco-pharyngea, buccinator muscle and the mucous membrane of the oral cavity opens at the level of the I or II superior molars. The whole facial expression musclesare innervated by the branches of the facial nerve. The subcutaneous fatty tissue also includes a.v.facialis (a. is a branch of external carotid artery, vein enters into the internal jugular vein). Facial artery passes to the face from the neck region, bending around the lower margin of the mandible at the level of anterior marginofmasseter muscle, where lies more superficially in the fat, and can be pressed to the bone in case of wounds of the facial region.The facial arteryand vein are projected by the line from the midpoint of horizontal branch of mandible or from anterior margin of masseter muscle to the medial angle of the orbit. Often the anesthesiologistsuse the facial artery to define the pulse in this zone in case ofthe intubation narcosis. As usual artery has winding way, whereas vein always passes straightly and is locatedposteriorly to the artery. At first it is situated superficially but then goes under the facial expression muscles. Branches of thefacial artery are: 1. Upper and lower labial arteries (aa. labialessuperior et inferior) –toprovide the arterial supply of the upper and lower lips. 2. Angular artery(a.angularis) – is the terminal branch of the facial artery. Facial artery in the medial angle of the eye is called angular artery and makes anastomosis with a. dorsalisnasi(branch of ophthalmic artery which arises from the internal carotid artery). Due to it an anastomosis between external and internal carotid arteries is formed. The angular artery is projected by the nasobuccal fold.In this course the facial artery makes anastomosis with a.transversafaciei, a.buccinatoria, a.infraorbitalis, a.mentalis. As a result of such a wide anastomosis in subcutaneous fatty tissue there is: bleeding is from both ends of the wounds, vasomotor reactions are well developed, wounds are infected rare, wounds heal rapidly, autodermoplastic reconstructive surgery practice is possible here. Between two buccolabial folds the region is called “corona mortis”, because of widely anastomoses and connection with the intracranial sinuses. The facial vein which form the facial common vein begins from the angular vein.Angular vein is formed at the medial angle of the eye by joining of supraorbital and supratrochlear veins (vv. supraorbitalisetsupratrochlearis).V.angularis anastomoses with the nasofrontal vein, by which venous blood through v.ophthalmica superior, then v. ophthalmica goes to the cavernous sinus. At the level of the mouth 8 angle, the superficial veins have an anastomosis with sinus cavernosus.At the level of the nasal wings, the facial vein has an anastomosis by v.facialisprofunda with plexus venosuspterygoideusof the deep facial region. In normal case facial vein drains down into v.jugularisinterna. Due to these numerousanastomoses and absence of valves inside of the facial veinsthe infection can spread retrograde to the sinus cavernosus when there is thrombosis of the facial veinor by the reason of pressing to the facial vein by edematousfluid or by exudate in case of suppurations, which are localized on the upper lip, wings of nose or its’ external aspect. Infection also can spread inside of the cranial cavity. Septic embol(clot), reaching to the cavernous sinus, can cause development of phlebitis, sinus-trombosis, meningitis or pyaemia. Nerves, located in the subcutaneous fat of this region, are the branches of facial and trigeminal nerves. The arterial supply and innervations of thebuccal region, besides the above mentioned, are provided by the following neuro-vascular structures: Ι. A.v.n.infraorbitalis – come from the same forameninto the fossa canina, which is on the anterior surface of the body of maxilla.The artery(a.infraorbitalis) is the branch of maxillary artery(branch of a.carotisexterna)in the pterygopalatine fossa,firstly passes into the orbital cavity through the lower orbital fissure (fissure orbitalis inferior), then through the infraorbital canal (canalisinfraorbitalis) turns inside of the buccal region, where gives branches within the fossa canina. The vein(v.infraorbitalis) drains into the v.ophthalmica inferior or into the plexus venosuspterygoideus. The nerve(n.infraorbitalis) is from second division of trigeminal nerve, continuation of maxillary nerve(terminal branch of n.maxillaris), which exits from the same foramen andforms the pesanserinus minor, which is in the fat at the anterior aspect of the maxillary body. Branches of the nerve form upper dental plexus (plexus dentalis superior), innervating the skin and mucous membrane of the upper lip, wings of the nose, maxilla and upper teeth. Projectional point of the main neuro-vascular bundle (a.v.n. infraorbitalis) coincides with an imaginary point, which is 0.5 cm below the midpoint ofthe lower orbital margin (margoorbitalis inferior). ΙΙ.Mental neuro-vascular bundle (a.v.n.mentalis), exits from the same opening (foramen mentale) of mandible into the subcutaneous fatty tissue.Nerve(n.mentalis) is from n.alveolaris inferior (n.mandibularis):innervates the skin and mucous membrane of the lower lip. Artery(a. mentalis) is the branch of the inferior alveolar artery (a.maxillaris): passes in the mandibular canal, passes through the foramen mentale to the region of chin, supplying the muscles of the lower lip and chin. Mental neuro-vascular bundle is projected by cross point between midpoint of the height of the body of mandible and midpoint of the distance between mental eminence (eminentiomentale) and anterior margin of the masseter muscle (between first and second praemolars). From the practical point of view the above mentioned projections are very useful for the anesthesia or blockade of the nerves in case of neuritis.

ΙΙΙ.Buccal nerve (n.buccalis), sensory branch of the mandibular nerve, IV.Buccal branch(ramus orn.buccalis), motor branch of the facial nerve, V.Buccal artery and vein (a.v.buccinatoria), branch of maxillary artery and vein, VI.Transverse artery of the face (a.v.transversafaciei), branch of temporal superficial artery and vein, 3. The superficial fascia is after subcutaneous fatty tissue. Superficial fascia is a very thin, densesheet, located in the subcutaneous fatty tissue and forms sheaths for the facial expression muscles, superficial vessels and nerves. 4. Fascia bucco-pharingeas covers the external surface of them.buccinator and in the posterior compartment fascia passes to the lateral wall of the pharynx where it covers it. 5. Mucous membrane of the vestibule of the oral cavity. Main sources of the infection and ways of the spreading into the buccal region: 1.Focus (foci) of the odontogenous infection in the region the upper and lower molars and premolars. 2.Infected wounds of the skin and mucous membrane of cheeks. 3.Spreading of the inflammatory process from the neighbouringregions – infraorbital, temporal, infratemporal and pterygopalatinepotches (fossas), from the parotideo-masseteric region. Inflammatory process in case of the buccalphlegmonecan spread to the following regions: 9

1.zygomatic region 2.infratemporal region 3.infraorbital region 4.parotideo-masseteric region 5.submandibular region 6.temporal region 7.orbital region 8.cranial cavitys

Parotideomasseteric Region (regio parotideo-masseterica)

1. Skin is thin, is covered by hair in male. Does not form the folds because of connective tissue’s strands connect the skin with the underlying fascia. 2. Subcutaneous tissue includes superficial vessels and nerves, superficial parotid lymph nodes. 3. Superficial fascia is thin layer. 4. Fascia parotideo-masseterica is the continuation of the superficial lamine of the proper neck fascia (by Shevkunenko) on the lateral facial region. It forms capsules for the parotid gland and masseter muscle. And consequently is called masseteric and parotid fascia (fascia masseterica et fascia parotidea), parts of the fascia parotideomasseterica, which cover consequent structures. Superiorly parotideomasseteric fascia is fixed to the periosteum of the zygomatic arch and body of the zygomatic bone, anteriorly passes into masseteric fascia (f. masseterica), inferiorly continues as a superficial sheet of the II fascia of the neck, attaching to the margin of the mandible. Fascia parotideomasseterica consists of two sheets. External sheet is more thick, it covers parotid salivary gland and gives dense septas inside of it, dividing the gland into lobes. Deep sheet of the fascia forms the coach of the parotid gland. It’s more thin and has many defects. One of them is located above the place, where gland adjoins to the cartilage of the meatus acusticus externus, where are present fissures for the passage of the lymphatic vessels. Through these fissures purulent processes of the gland can be opened into the external acoustic meatus. The other defect of the capsule is situated on the protrused part of the pharyngeal process of the gland (posterior surface), which isn’t covered by capsule and is between styloid process of the temporal bone and posterior margin of the medial pterygoid muscle. Such way inflammatory process can spread to the parapharyngeal space from the capsule of the parotid gland. The deep sheet of the fascia adjoins to the styloid process, muscles (mm. stylopharyngeus, styloglossus et stylohyoideus), and to the ligaments of stylomandibular and stylohyoid muscles (ligamenti stylomandibularis et stylohyoideus). All these structures form the “anatomical bunch ” or “anatomical bouquet”. The lower wall of the coach of the parotid gland separates it from the coach of the submandibular salivary gland . M. masseter starts from the zygomatic arch, turns down and backwards (inferiorly and posteriorly), attaching to the mandibular angle. It’s covered by the masseteric fascia (f. masseterica). Between m. masseter and the branch of mandible (ramus mandibulae) is situated the masseterico-mandibular space, which is filled with loose connective tissue, where pus can be accumulated in case of phlegmones of the region. From the deep facial region above the incisura mandibulae masseteric neuro-vascular bundle (a.v.n. massetericae) penetrates here, entering the muscle from its’ inner surface. Inferiorly and partly posteriorly space is limited by the attachment of the masseteric muscle to the mandible. Superiorly space isn’t limited and under the zygomatic arch is widely connected with the subaponeurotical space of the temporal region. Besides that, by the direction of the vessels it’s connected with the deep lateral facial region. Inflammatory processes of the region frequently have odontogenous origin. The parotid gland - the small (anterior) part is located on the surface of m.masseter, the large (posterior) part of the parotid gland is situated in the retromandibular fossa, which is bounded by Anteriorly – the ramus of the mandible and the medial pterygoid muscle; Posteriorly – the tendons of the m.sternocleidomastoideus and posterior belly of m.digastricus; Superiorly – inferior wall of the external acoustic meatus.

It (retromandibular space) has a shape of the pyramid with the apex directed medialy and back. The gland has deep and superficial parts. Deep part is situated between styloid process and medial pterigoid muscle, turns into the lateral parapharyngeal space. The deepest part of the deep region is called pharyngeal process (processus pharyngealis). Superficial part – on the m.masseter. From the capsule to inside the gland continues the connective septa, which subdivide the gland into the lobes, making the structure of the gland interlobular. That’s why the inflammation process will be in located manner, it does not spread through whole gland. Syntopy: anterior wall of the gland adjoins to the lateral surface of m. masseter, to the branch of the mandible behind m. masseter and to the posterior margin of the medial pterygoid muscle. Medial wall adjoins to the parapharyngeal space, styloid process and to the muscles, starting from the process (m. styloglossus, m. stylopharyngeus, m. stylohyoideus). V. jugularis interna (internal jugular win) lies here directly on the parotid fascia (fascia parotidea). Posterior wall of the gland contacts with m. sternocleidomastoideus and the posterior belly of the digastric muscle (ventes posterior m. digastrici) and can reach to the mastoid process. Lateral wall is under the skin and is covered with the subcutaneous fatly tissue. Superior wall passes anteriorly to the ear and turns upwards to the zygomatic arch, posteriorly and inferiorly adjoins to the lower surface of the cartilage of meatus acusticus externus and to the capsules of the temporo-mandibular joint. Inferiorly the gland is separated from the submandibular gland by a thickened part of the proper fascia of neck. Additional lobes of the gland, which differ by their sizes and quantity, are often met. Inside from the capsule in the thickness of the gland are situated the deep parotid lymph nodes, fatty pad and arteriovenous bunches. Deep parotid lymphatic nodes are subdivided into 3 groups: I. Preauricular lymph nodes (nodi lymphatici preauriculares. II. Infraauricular lymph nodes (n. a. infraauriculares). III. Intraglandular lymph nodes (n. l. intraglandulares) are in the thickness of the gland, mainly by the direction of a. carotis externa. sNeuro-vascular structures of the parotid gland: 1. Facial nerve (n. facialis), exits from the stylomastoid opening of the temporal bone (foramen stylomastoideum) into the lateral facial region posteriorly from the retromandibular potch, where it’s located below the place of the attachment of the lower end of auricle(cochlea) (a guide to find the main trunk of the nerve quickly). After leaving the facial canal through the stylomastoid foramen gives off the auricular posterior nerve. Then facial nerve through the internal sheet of the parotid fascia enters the parotid gland (inside of its’ capsule) in its’ superior-posterior part approximately at the level of the lower semicircle of the auricle(cochlea) - intraglandular part of the nerve. Inside of the capsule of the gland it turns anteriorly, locating more superficial from the big vessels. Facial nerve in the thickness of the gland close to the anterior glandular surface at a depth of 1-2 cm, separates into its’ superior and inferior branches. Inside the gland from these branches go widely communicating branches to each other and form the plexus parotideus, also called “pes anserinus major”, surrounded from all sides with glandular tissue, hence extraction of the gland without damaging of this plexus is impossible. The superior branch gives off the following branches: temporal ( rr.temporales), zygomatic (rr. zygomatici) and buccal (rr. buccales), which pierce the anterior margin of the capsule of the gland, then the proper fascia of m. masseter and appear in the subcutaneous fat, where they pass radially, turning to the deep surface of the facial expression muscles and innervating them (motor nerves). The inferior branch gives off two branches: the mandibular marginal branch (r. marginalis mandibulae), factually the continuation of the lower branch, passes parallel to the lower margin of the mandible to the muscles of the chin and lower lip (its’ topography is important in case of exposure and ligature of the a. facialis at the level of the margin of the mandible) and the cervical branch (r. colli) - the second branch, descends onto the neck, where anastomoses with the branches of the cervical plexus. Damaging of these branches leads to real cosmetic defects. For not to damaging the branches incisor lines should be parallel to them and from the posterior surfaces of the facial expression muscles. To avoid severe complications after damaging of the branches of n.facialis, which cause paresis and palsy(paralysis) of the facial expression muscles, is necessary to know their projections. 11

Terminal branches of n. facialis are projected by lines, passing fan-like from a point, located anteriorly to the tragus of the auricle (cochea) or one transverse finger below the external acoustic meatus. If the palm of the hand will put on the gland area, the fingers will show the branches projections: First finger to the middle of the zygomatic arch - r.temporalis; Second finger to the upper, lateral angle of the orbit - r. zygomaticus; Third finger to the upper lip (parallel to the zygomatic arch) – r. buccalis; Fourth finger to the margin of mandible or 1-1,5cm down - r. marginalis mandibulae; Fifth finger vertically down - r. colli. Because of the topographical peculiarities of the branches of the facial nerve, radial sections must be done from the anterior part of the ear to avoid damaging of a number branches of the facial nerve. In case of inflammatory processes inside of the gland as a complication combined injury of the branches of n. facialis is possible. 2. V. retromandibularis accompanies the external carotid artery and in the thickness of the gland is situated superficially from the external carotid artery. It forms by connection of several veins: v.temporalis superficialis v.temporalis media v.temporalis profundus anterior, posterior v.transversa faciei v.maxillaris After leaving the gland V. retromandibularis separated into its anterior and posterior branches. The anterior one join to the facial vein and form the common facial vein(v.facialis communis), which drains into the internal jugular vein. The posterior one with v.occipitalis and v.auricularis posterior form the external jugular vein. 3. External carotid artery (a. carotis externa) – is one of the terminal branches of the common carotid artery, ascends into the lateral facial region – fossa retromandibularis, from the region of neck and at the level of the basis of mandible’s branch, piercing the capsule, enters inside of the coach of the parotid gland from its’ deep medial side, in the thickness of the gland is located deeper than the vein. Upon which it turns in obliquely vertical direction, surrounded with glandular tissue from all sides, and at the level of mandibular articular head is subdivided into its’ two terminal branches – the a.maxillaris, which pierces the posterior wall of capsule, surrounds the mandibular head and goes to the deep facial region, and a.temporalis superficialis, ascending to the temporal region as a continuation of the trunk of a.carotis externa. The last one (a. temporalis superficialis) while inside the gland gives off the a.transversa faciei, which turns to the cheek by the external surface of m. masseter, locating above and parallel to the parotid duct. 4. The auricolotemporal nerve (n.auriculotemporalis) is also present inside of the gland, which starts from the mandibular nerve in the deep lateral facial region close to the oval opening (foramen ovale) with two bundles (fasciculi), which surround a. meningea media. Then nerve passes by the medial surface of mandible, and posteriorly bending around the neck of mandible, pass in the capsule of the parotid gland and rises up in its’ thickness. Here it gives connective branches to n. facialis, branches to the tissue of the gland, to the external acustic meatus, to the tympanic membrane. Together with a. temporalis superficialis, locating medially, then anteriorly to the artery, auriculotemporal nerve penetrates through the posterior surface of the capsule of the gland and rises vertically up anteriorly to the external acoustic meatus to the skin of the temporal region. Parotid duct (or Stenon s. Stensen duct) arises from the anterior border of the parotid gland and passes (with a.v.transversa faciei and r.buccalis of the facial nerve) at the external surface of the masseter muscle inferiorly to the zygomatic arch (about 1 cm or one transverse finger), surrounds anterior margin of the muscle. During the operation duct is defined by numerous veins, bending it around. Also as a guide can serve a. transversa faciei, passing parallel and a little above the duct. If duct is damaged, hence salivary fistula of parotid gland may develop. This complication can be treated only surgically, by restoring of the duct reconstructive operation- plastics, because amylase (enzyme of saliva) has a great activity and is a barrier for the regeneration of tissues. In the posterior-superior compartment of the parotideo-masseteric region is located the temporo- mandibular joint (articulation temporo-mandibularis), which is formed by the mandibular head and mandibular depression of the infratemporal bone. Joint is closely neighboring to the parotid gland, that’s why extraction of 12 the articulate process (processus articularis) is dangerous: it causes damaging of the gland, arteries and veins, located close to the joint.

Main sources of the infection and ways of the spreading into the parotideo-masseteric region: 1. Focus (foci) of the odontogenous infection in the region the lower third molars. 2. Lymphogenous way from odontogenous infection of upper molars 3. Spreading of the inflammatory process from the neighbouring regions – buccal, temporal and infratemporal fossa. Inflammatory process in case of the buccal phlegmone can spread to the following regions: 1. To reetromandibular fossa then to the parapharingeal space along neuro-vascular bundle of the neck and anterior mediastinum. 2. Submandibular region 3. Buccal region 4. Infratemporal fossa, temporal region, orbit and cranial cavity

Deep Facial Region (regio facialis profunda)

Deep facial region, which occupies the infratemporal fossa is visible if we remove zygomatic arch, masseter muscle and ramus of mandible. Boundaries of this region are: anteriorly – tuber maxillae and the base of the zygomatic arch; posteriorly – anterior margin of the parotid gland; medially – pterygoid process of the sphenoid bone and lateral wall of the pharynx. laterally – masseter muscle with it’s fascia. Infratemporal fossa is the direct continuation of the temporal fossa and is divided from the last one s by the infratemporal crest (crista infratemporalis) of the great wing of the sphenoid bone (ala major os sphenoidei). Inferiorly it’s bordering with the oral cavity (cavitas oris), posteriorly – by the styloid process with the “anatomical bunch” (“bouquet’). Infratemporal fossa medially passes into the fossa pterygopalatina. The last one has a fissure-like form and is situated between pterygoid processes posteriorly and tuber maxillae anteriorly. Pterygopalatin fossa limited: Posteriorly – pterygoid process pf sphenoid bone Superiorly – great wing of the sphenoid bone. Anteriorly – tuber maxillae Medially - perpendicular plate of the palatine bone, which divides it from the nasal cavity. Laterally - connected widly with temporal fossa.

The deep facial region consists of the mentioned potches (fossas) and one of them is the infratemporal fossa, which includes fat, pterygoid medial and lateral muscles, numerous vessels and nerves, also here passes tendon of the temporal muscle. Lateral pterygoid muscle (m. pterygoideus lateralis) starts from the inferior surface of the great wing of the sphenoid bone and external lamina of the pterygoid process. Direction of the muscular fibres is approximately horizontallaterally and posteriorly, attaches to the neck of the mandibular articulate process and to the capsule of the temporo-mandibular joint. Medial pterygoid muscle (m. pterygoideus medialis) starts from the depression of the processus pterygoideus, goes down and laterally, attaches to the medial surface of the mandibular angle. In the deep facial compartments there are cellular spaces or so called intermuscular fissures, located between the mandibular branch (ramus mandibulae) and tuber maxillae. These spaces will be presented later.

In the deep facial region is situated the pterygoid venous plexus (plexus pterygoideus), which is the most superficial structure and communicates with cavernous sinus through the inferior ophthalmic vein, emisar veins at the foramen ovale and foramen lacerum. The plexus pterygoideus by the v.facialis profunda connects with the facial vein at the level of the nasal wings. 13

The bigger part of the plexus lies on the external surface of the lateral pterygoid muscle, between the last one and temporal muscles, hence in the temporo-pterygoid space. Another part of the plexus is located on the deep surface of the lateral pterygoid muscle. Deeper to the venous plexus and mostly in the interpterygoid space there is maxillary artery which is a branch of external carotid artery and gives branches inside of the glandular capsule of the parotid gland a bit below from the mandibular neck (collum mandibulae) and, bending around the neck, passes in the deep lateral facial space in transverse direction medially and a little superiorly to the fossa pterygopalatina, locating on the external surface of the lateral pterygoid muscle. A.maxillaris conditionally is divided into three compartments (depending on the place of localization): 1. At the level of the mandibular neck (collum mandibulae), adjoining posteriorly to the capsule of the temporo-mandibular joint (this must be reminded in case of operations on the joint). 2. At the level of the infratemporal fossa – in the temporo-pterygoid space, between lateral pterygoid and temporal muscles. 3. At the level of the fossa pterygopalatina. 1. It gives off several branches in it’s first part at the level of the mandibular neck (branches of the first compartment): - a. meningea media - ascends by the medial surface of the lateral pterygoid muscle and enters into the cranial cavity through the spinous opening (foramen spinosum), being surrounded with the initial bundles of the n.auriculotemporalis, - a. alveolaris inferior - passes through the mandibular opening (foramen mandibulare) into the mandibular canal (canals mandibulare), vascularizing the lower teeth, emerges through foramen mentale and is called a.mentalis, - deep auricular artery ( a. auricularis profunda) - tympanic artery (a. tympanica) - additional meningeal artery (a.meningea accessorius) 2. In it’s second part in infratemporal fossa it gives off (branches of the second compartment): - a. masseterica, for the consequent muscle, - anterior and posterior deep temporal arteries (aa. temporales profundi anterior et posterior), provide arterial supply of the temporal muscle, - a. buccinatoria, which passes anteriorly and down along the external surface of the buccal muscle, - aa.pterygoidei lateralis et medialis, to the corresponding muscles. 3. In it’s third part in pterygopalatine fossa it gives off (branches of the third compartment): - a.sphenopalatina, one of the terminal branches of the maxillary artery, through the foramen sphenopalatinum enters into the nasal cavity, then supplies lateral wall and septa of the cavity, - a.palatina descendens - the 2-nd terminal branch of the a maxillaris , which goes to the oral cavity by the greater palatine canal, - a.alveolaris superior posterior, - a.infraorbitalis, which passes through the infraorbital canal, emerges on the anterior facial surface through the infraorbital opening in the fossa canina and gives off the a.alveolaris superior media et anterior. Besides the maxillary artery and the pterygoid venous plexus, in deep facial region also is located the mandibular nerve( n. mandibularis), which has the most deepest position. N. mandibularis – is the 3-rd branch of the trigeminal nerve, leaves the skull through foramen ovale into the deep lateral facial region inside of the interpterygoid space under the lateral pterygoid muscle. Extracranial part of the nerve is very short (0.5cm), because of exiting from the skull is divided at once and gives off the following branches: 1. n. auriculotemporalis, – is sensitive nerve, passes by the inner surface of the articular process of the mandible by the bursa of the joint, anteriorly from meatus acusticus, through the parotid gland. Gives branches to the temporomandibular joint, parotid gland and the meatus acusticus externus, 2. n. buccalis, – sensitive – through the fissure between two parts of the lateral pterygoid muscle passes down and anteriorly to the external surface of the buccal muscle, pierces it and gives branches in the mucous membrane of the cheek and in the skin of the angle of the mouth. Anesthesia of this nerve can be provided intraorally (intraoral method): for the blockade of the buccal nerve anesthetic is injected in the transitory fold of the oral vestibulum in the region of the tooth, which is going to be extracted, 14

3. n. lingualis, – sensitive - turns inferiorly and medially, locating on the external surface of the medial pterygoid muscle medially to n. alveolaris inferior. At the level of the upper margin of the medial pterygoid muscle tympanic chord (chorda tympani) joins to the lingual nerve superiorly and lateralsly, which comes from facial nerve (n. facialis) and innervates submandibular and sublingual salivary glands. Passing under the mucous membrane of the floor of the mouth, lingual nerve gives branches to it and to the mucous membrane. 4. n. alveolaris inferior, - mixed nerve – emerges under the lower margin of the lateral pterygoid muscle, then passes in the space between branch of the mandible and medial pterygoid muscle and finally enters the mandibular canal through the mandibular opening. Posteriorly to it pass same artery and vein. Before entering to the opening gives branch - n. mylohyoideus, passing in the mylohoid groove on the inner surface of the mandible to the mylohoid muscle and the anterior belly of the digastric muscle (venter anterior m. digastrici). In the mandibular canal inferior alveolar nerve (n. alveolaris inferior) gives branches to the lower teeth, with formation of the dental plexus (plexus dentalis inferior). The terminal branch and the direct continuation of the lower alveolar nerve is the mental nerve (n. mentalis), which passes to the subcutaneous fat from the mental opening (foramen mentale) together with the samel vessels and innervates skin of the chin and lower lip. The position of the n. alveolaris inferior on the inner surface of the mandibular branch is used for the mandibular anesthesia. Piercing of the mucous membrane and injectsion of the anesthetic solution is provided above the level of the lower molars (midpoint of the height and width of the branch of the mandible). Transmission of the infection from tooth to the jaw can cause development of an infiltrate, which will press vessels and nerves passing inside of the canal. Pressure of the inferior alveolar nerve by the infiltrate can destroy the conductivity of the nerve, owing to which appears anesthesia of the half part of the lip and chin on the injured side. Thrombophlebitis of v.alveolaris inferior causes edema of face of the consequent half of the mandible and lower lip. 5. n masseter (n. massetericus), – is mostly motor nerve – passes across the incisura mandibulae above the upper margin of the lateral pterygoid muscle to the m. masseter. Gives a sensitive branch to the temporo-mandibular joint. 6.nn.temporales profundi anterior et posterior, - motor by function – turn upwards and anteriorly to the basis of the skull, bending around the infratemporal crest and innervate the m. temporalis. 7. nn.pterygoidei medialis et lateralis, - motor – innervate consequently medial and lateral pterygoid muscles. To exposure of the mandibular nerve lateral pterygoid muscle must be entirely removed. To the retromedial surface of the n. mandibularis below the oval opening (foramen ovale) adjoins ganglion oticum, which is connected with the mandibular, auriculotemporal and other nerves. Motor fibers of this ganglion supply the mastication muscles. During operations on the mandibular nerve injury of ganglion oticum is possible. This is the reason of the palsy (paralysis) of the whole mastication musculature on the consequent side. Posteriorly to the exit of n. mandibularis from the oval opening a. meningea media passes (turns to the spinous opening). During operations on the extracranial part of the mandibular nerve is important to pay attention at the nearness of this artery. N. maxillaris has deepest localization, which is the 2-nd branch of the trigeminal nerve and exits from the middle cerebral poach through the round opening (for. rotundum) into the deepest internal compartment of the deep facial region – fossa pterygopalatina. In the fossa pterygopalatina maxillary nerve gives numerous sensitive branches. The bigger branches of them are: - zygomatic nerve (n.zygomaticus), - infraorbital nerve (n. infraorbitalis), - upper alveolar nerves (nn. alveolares superiores), which give posterior, middle and anterior branches. Inferiorly and medially to n. maxillaris is located the ganglion pterygopalatinum, to which maxillary nerve gives sensitive branches (nn. pterygopalatini). Nn. palatini start from the ganglion, which pass through canalis pterygopalatinum to the dure and soft palate (palatinum durum et molle) (together with a. palatina descendens) and posterior nasal branches (rr. nasales posteriores), which reach to the nasal cavity through the sphenopalatine opening (foramen sphenopalatinum). 15

Fossa pterygopalatina communicates with other compartments of the facial region by the help of the following openings: . Through the foramen sphenopalatinum – with the nasal cavity, where pass a.v. sphenopalatina and nn. nasales posteriores. . Through the round opening (for.rotundum) – with the cavity of the middle cerebral poach, where passes the 2-nd branch of trigeminal nerve. . Through the fissura orbitalis inferior – with the orbital cavity. . Through the canalis pterygopalatinus – with the oral cavity, through which pass palatine vessels and nerves . Through the canalis pterygoideus – with the basis of the skull, where passes pterygoid nerve. . Superiorly – to the temporal fossa, . Medially – to the parapharyngeal connective tissue, . Through the pterygopalatine process of the adipose body – to the buccal region,

Cellular spaces of the deep facial region

There are two cellular spaces (by Pirogov) in the deep facial region: temporopterygoid (spatium s. interstitium temporopterygoideum) and interpterygoid (spatium s. interstitium interpterygoideum), located between both pterygoid muscles. The interpterygoid space is subdivided into external and internal compartments. The external compartment in stomatology is the well-known pterygomandibular space (spatium pterygomandibulare). In both interfascial cellular spaces, divided from each other by the lateral pterygoid muscle and connected to each other, pass pterygoid venous plexus (plexus venosus pterygoideus), maxillary artery (a.maxillaris) and branches of the mandibular nerve (n. mandibularis), surrounded with cellular tissue. Cellular tissue of these spaces directly or by the direction of vessels and nerves spreads to the neighboring regions, connecting them to each other. Temporo-pterygoid space is bounded: laterally – by the terminal part of m.temporalis, which attaches to the coronary process of the mandible, medially – by the lateral pterygoid muscle, anteriorly – by the tuber maxillae (spur of the maxillary bone), posteriosly – by the articulate process (processus articularis) of the mandible.

Communications (ways of spreading of the pathological process) . Upwards – by the direction of the temporal muscle to the temporal fossa (space between the muscle and the periosteum of the temporal bone). . Laterally – by the direction of the maxillary artery, cellular space is connected with the capsule of the parotid gland. . Posteriorly and superiorly – by the direction of a. meningea media or branches of the trigeminal nerve through the spinous, oval and round openings (foramen spinosum, f. ovale, f. rotundum) - with the cranial cavity. This connection is very important from the practical point of view, because suppuration of the temporopterygoid cellular space can can spread to the dura mater. . Posteriorly and medially – with the fossa pterygopalatina and orbit. . Inferiorly –with the floor of the oral cavity by the direction of the lingual nerve (n. lingualis). . Anteriorly – with the cellular space of the buccal region by the process of Bichat’s adipose body. Interpterygoid space is limited: medially and inferiorly – with medial pterygoid muscle laterally – with the inner surface of the lateral pterygoid muscle and the mandibular branch superiorly – with the external surface basе of the skull. Interpterygoid space superiorly passes to the cellular tissue of the temporopterygoid space. That’s why phlegmones (generalized purulent inflammations) of these two described spaces have same ways of spreading of pathological process.

Usually the reason of the pterygomandibular phlegmone is late or wrong treated complications of dentition (eruption of teeth (teething) of 3-rd molars, also inflammation of periapical tissues in the region of the lower 7-8-th teeth, infection of the haematomas in case of technically wrong provided tuberal anesthesia (anesthesia of the maxillary soft tissues (of the upper jaw). In case of phlegmone medial pterygoid muscle involves in the process, upon which develops a special condition, called lockjaw or masticatory spasm – inflammational constriction of the named muscle. This condition causes difficulties with the opening of the mouth. Further spreading of the infection can cause phlebitis of the veins of pterygoid venous plexus and later on inflammational process can spread on the veins of the orbit. Phlegmone can spread to the following spaces: . retromandibular fossa, . temporal fossa, . fossa pterygopalatina, . submandibular space, . infratemporal fossa, . anterior compartment of the parapharyngeal cellular space. Cellular tissue, surrounding the pharynx (throat), forms the parapharyngeal and retropharyngeal cellular spaces, which have considerable role in the development of the purulent processes on the head. Parapharyngeal space (spatium parapharyngeum) is situated deeper to the deep lateral facial region (surrounds the pharynx from the back and sides). Boundaries of the parapharyngeal space are: laterally – medial pterygoid muscle and the capsule of the parotid gland; posteriorly – transverse processes of the cervical vertebrae; medially – lateral wall of the pharynx; superiorly – base of the skull; inferiorly – floor of the oral cavity at the level of the hyoid bone. Parapharyngeal cellular space is divided from the submandibular gland and its capsule by m. hyoglossus. Cellular tissue of the parapharyngeal space passes into the cellular tissue of the floor of the oral cavity. The parapharyngeal space is divided into lateral parapharyngeal space (spatium lateropharyngeum – from the both sides of the pharynx) and retropharyngeal (spatium retropharyngeum). The border between them is a fascial sheet, extending between pharyngeal and praevertebral fascias (between IV-th and V-th fascias of the neck by Shevkunenko). It’s called pharyngeoprevertebral aponeurosis (aponeurosis pharyngopraevertebralis) or Sharpy’s process. The lateral parapharyngeal (or proper parapharyngeal) space, in turn, is divided into two compartments – anterior -pterygopharyngeal and posterior -stylopharyngeal. The border, dividing these compartments, is a facial sheet, extending between styloid process and pharynx (aponeurosis stylopharyngea). Structures, adjoining to the medial and lateral walls consequently in the anterior compartment of the parapharyngeal space are: . medially – tonsilla paltina (palatine tonsil); . laterally – parapharyngeal (pharyngeal) process of the parotid gland, which is in the space between the medial pterygoid muscle and the styloid process. In the space branches of a. palatina ascendens (from a. facialis) and same veins (vv.palatinae ascendens are also located. By the direction of the veins spreading of inflammatory process from the palatine tonsils is possible (e.g. in case of peritonsillar abscess). Structures which pass in the posterior parapharyngeal space (which is called retrodiaphragmatic space by Voyno-Yasenetsky): . laterally – v. jugularis interna; . medially to the vein – a. carotis interna and 4 cranio-cerebral nerves: - n. glossopharyngeus (IX-th pair) - n. vagus (X-th pair) - n. accesorius (XI-th pair) - n. hypoglossus (XII-th pair) - cervical ganglions of n. sympathicus

- the most upper (supreme) group of deep cervical lymphatic nodes (nodi lymphatici cervicales profundi). Retropharyngeal space (spatium retropharyngeum), situated between pharynx with its fascia and prevertebral fascia (between IV-th and V-th sheets of the cervical fascia). Inferiorly this space passes to the retrovisceral space of the neck, which is connected with the posterior mediastinum. The retropharyngeal space by the median sept, extending from the suture of pharynx up to the prevertebral fascia, is divided into two compartments: right and left. Due to this retropharyngeal abscesses, as usual, are one-sided. Infection of the parapharyngeal space often appears in case of inflicting of VII-th and VIII-th teeth of the lower jaw and cellular tissue of the interpterygoid space. Also transmission of inflammational process to the above mentioned space (parapharyngeal) by the direction of the pharyngeal process of the parotid gland in case of purulent parotitis, or by the direction of the lymphatic vessels is possible. Inflammation of the cellular tissue of the parapharyngeal space causes such symptoms, as dysphagia (difficulty in swallowing) and in more severe cases dyspnea (difficulty,disorders in breathing). In case of quinsy (angina) may develop thrombophlebitis of the v.palatina ascendens, which receives blood from the palatine tonsils, with formation of phlegmone. From here process will spread to the facial veins, then to the jugular veins. If the infection from the anterior compartment of the parapharyngeal space penetrates in the posterior compartment (when stylopharingeal aponeurosis is destroyed), further spreading of the infection realizes by the spatium vasonevrorum of the neck into the anterior mediastinum. In case, when infection passes on the retropharyngeal space, later on spreading of the infection is provided along the esophagus into the posterior mediastinum. In case of purulent infliction of cellular tissue of the posterior compartment of the parapharyngeal space develops necrosis of the wall of a. carotis interna (with subsequent severe bleeding) or development of septic thrombosis of the internal jugular vein.

Operative surgery of the facial region Surgical treatment of the facial wounds

The primary surgical treatment of the facial wounds and wounds of the jaws is provided taking in account the anatomo-physiological peculiarities of the tissues and organs of the given region, direction of the wound canal, presence of posttraumatic defects and deformations of the facial tissues. Anesthesia Choice of the anesthetizing method depends on the type, prevalence and localization of the wound. Operation is provided under local infiltration and/or conduction anesthesia. In case of huge wounds – under the endotracheal narcosis. Position of the patient: lying on the back, with turned to the healthy side head.

Peculiarities of the mechanical cleaning (surgical treatment) of the wound When processing of the skin is finished, carefully provide the mechanical cleaning of the wound. Don’t make excision of the edges of the wound, but cut and remove only not viable and not vascularized tissues (economic al excision). Clean the wound from blood (hematoma), remove by the dissecting forceps superficially lying in the wound inner bodies, dirt lumps, metallic and also freely lying and free of periosteum bone fragments. Then carefully clean the wound with cotton pads, immersed in antiseptic solution. If the clean wound is processed in the 24 hours, tissues aren’t excised: in this place for the structural and functional recovery each, even very small part of tissue is very important, and also regeneration abilities will be better.

Injury of the parotid gland or its duct In this case put the sutures on the gland, fascia and skin to avoid formation of duct fistula in future. In case when duct is damaged provide the tube drainage towards the duct through the wound from the oral cavity side and suture the drainage for 10-12 days to create temporary artificial duct.

Main principles opening of the abscesses and phlegmones of the facial region.

Anastasia local as a rulles. Technique. 1.Skin – is incised by scalpel, depending on the pathological focus localization and topographical peculiarities of the region, hemostasis is done. 2. Subcutaneous fatty tissue – is separated bluntly (e.g. by the help of the arterial forceps) to the center of the infiltrate. 3. Fascias and muscles are incised by sharp (cutting by scalpel or by grooved probe helping) or blunt (separation along fibers) methods. 4. Evacuation of pus, processing of the cavity with antiseptic solution. 5. Thoroughly draining until the purulent contents will be entirely removed.

Opening of the abscesses and phlegmones of the buccal region

Choice of the operative access – depends on the localization of the infiltrate, topography of the main branches of n.facialis and Stenon duct (duct of the parotid gland). Can be extra- and intraoral. Incisions in the buccal region have radial direction: from the ear tragus up to the external angle of the eye, to the tip of the nose and to the angle of the mouth, parallel to the mandible margin and about 1-1.5cm below it. In case of abscess/phlegmone of the subcutaneous fat in the lower compartment of the buccal region, an incision, which is about 1-1.5cm below the mandible margin and parallel to it, is provided in the submandibular region. In case of abscess/phlegmone of the subcutaneous fat in the upper compartment of the buccal region skin incision is made by the nasolabial fold. In case of abscess/phlegmone of the deep cellular space of the buccal region intraoral access is used. The incision of the mucous membrane is provided by the direction of the parotid duct, above or below it depending on the localization of the process.

Opening of the abscesses and phlegmones of the parotideo-masseteric region

In case when process is located in the superior compartment of the region skin incision is provided radially through the center of the inflammatory infiltrate, parallel to the projection of the main branches of the facial nerve. In case when abscess is in the inferior compartment of the region skin incision is provided in the submandibular region parallel and about 1-1.5cm below the mandibular margin, due to localization of the mandibular marginal branch (r.marginalis mandibulae) here. Opening of the abscesses/ phlegmones of the massetero-mandibular space Incision of the skin and subcutaneous fat, inferiorly and posterior to margin of the mandible about 1.5- 2cm bending the angle. Opening of the abscess/ phlegmone of the retromandibular fossa Incision the skin and subcutaneous fat along the mandibular margin about 1cm below it, continuing the incision to the retromandibular fossa. Opening of the phlegmone of the parotideo-masseteric region in case when several cellular spaces are inflicted Operative access: combined- submandibular and infrazygomatic, at the same time operational wounds of two regions join to each other. Incision of the soft tissues inferiorly and posterior to margin of the mandible about 1.5-2cm bending the angle layer-by-layer. The next step is the incision of the skin in the parotid region parallel to the lower margin of the zygomatic bone. Stratify the fat, filling the space between the parotideo-masseteric fascia, parotid gland and masseter muscle, towards the operational wound in the submandibular region. Form a wide tunnel, joining these two wounds. Drain the formed wide tunnels in the subcutaneous and subfascial fat of the parotideo-masseteric 19 region. In case when process spreads into the retromandibular fossa or massetero-mandibular space, provide draining of them (these spaces), too.

Opening and draining of the abscesses/phlegmons of the temporal region

Sources and ways of spreading of infection into the temporal region: -pyoinflammatory diseases of the skin (furuncul, carbuncul) -infected wounds -hematomas of the temporal region -phlegmons of the neighbouring regions (infratemporal fossa, frontal, zygomatic, parotideo-masseteric, buccal)

There are the following types of phlegmons depending on the location of the purulent-inflammatory process: Superficial. Interaponeurotic. Subaponeurotic. Deep. Generalized. The superficial phlegmon, abscess : are located in the subcutaneous fat. Incision is provided behind the frontal process of the zygomatic bone between the passing fan-like temporal branches of the facial nerve under local anesthesia. The interaponeurotic phlegmon, abscesses: are located over the zygomatic arch between the superficial and deep sheets of the proper temporal fascia. Incision have done along the superiormargin of zygomatic arch. Subaponeurotic phlegmon, abscesses: are located between the deep sheet of the proper fascia and the temporal muscle (superficially in the temporal fossa). Provide radial or arcuate incisions by the inferior temporal line through the center of the inflammatory infiltration at the whole length of it. The deep phlegmon, abscesses of the temporal region: are located between the temporal muscle and the periosteum (deeply in the temporal fossa). Provide an arcuate incision by the line from the place of attachment of m.temporalis to the temporal bone. Generalized phlegmone of the temporal region: an inflammatory process, which involves all three above mentioned cellular spaces. This phlegmon is opened using an arcuate incision by the direction of the inferior temporal line of the temporal bone and a horizontal incision by the upper margin of the zygomatic arch.

Opening and draining of the abscesses and phlegmons of the infratemporal and pterygo-palatine potches

Operative access can be intraoral or combined with the extraoral. In case of the initial stage of the purulent process and abscesses intraoral access is used. In more aggravated cases, especially in case of the phlegmon, intra- and extraoral incisions are unimomently provided. Intraoral access The incision of the mucous membrane is provided by the transitory fold of the posterior compartment of the fornix vestibulae oris. After dissection of the mucous membrane by the periosteum pass behind the tuber maxillae posteriorly, superiorly and medially to the infratemporal fossa. Open the suppuration. Extraoral access Skin incision is done by the anterior margin of the temporal muscle. After dissection of the skin, subcutaneous fat and temporal fascia, retract the fibers of the temporal muscle, penetrate up to the squama of the temporal bone, and bending around the crista infratemporalis, enter the infratemporal fossa.

TOPOGRAPHICAL ANATOMY & OPERATIVE SURGERY OF THE NECK. TOPOGRAPHICAL PECULARITIES OF THE REGIONS (TREUNGLES) OF THE NECK AND ITS PRACTICAL IMPORTANCE. MAIN PRINCIPLES OF SURGICAL TREATMENTS

Boundaries of the Neck Superior boundary is the inferior border of the mandible, anterior and posterior margins of mastoid processes of temporal bones till asterion, superior nuchal line of occipital bone. Inferior boundary is the superior margin of manubrium sterni and clavicles, the imaginary line between acromions and spinous process of the 7-th cervical vertebra. The neck is divided into two regions: anterior and posterior, by means of an imaginary frontal plane and frontal septa of the second fascia of the neck which pass anteriorly from the trapezius muscles and attach to the transverse processes of the cervical vertebrae. Posterior region (regio cervicis posterior) is also called nuchal region ( regio nuchae) The frontal part of the neck (regio cervicis anterior) is bisected by sternocleidomastoid muscle (SCM) diagonally into anterior and posterior cervical triangles. Anterior (medial) triangle of the neck is divided into suprahyoid and infrahyoid regions by the hyoid bone and posterior bellies of digastric muscles. In the suprahyoid region we describe submandibular and submental triangles. The infrahyoid region is divided into carotid and omotracheal triangles by the superior belly of omohyoid muscle. Posterior (lateral) triangle of the neck is divided into omotrapezoid and omoclavicular triangles by the inferior belly of omohyoid muscle. Fasciae of the Neck Fasciae of the neck by Shevkunenko are divided into five ones. This classification of five fasciae is more necessary for surgical intervention. I fascia is superficial cervical fascia. It is usually a thin layer, which surrounds the neck and contains the platysma. This fascia is continued by general superficial fascia of the whole body. It doesn’t have any place of attachment on the neck. In PNA this fascia is not described. II fascia is lamina superficialis fasciae colli propriae (PNA lamina superficialis fasciae cervicalis) surrounds the structures in the neck. It contains the SCM and trapezoid muscle and submandibular gland. II fascia begins from the spinous processes of the cervical vertebrae, traverses anteriorly and includes the trapezoid muscle. From the anterior border of the trapezoid muscle the II fascia forms transverse septa to the transverse processes of the cervical vertebrae and divides the cervix into anterior and posterior parts. Inferiorly, it is attached to the • Anterior surface of the manubrium and clavicles • Acromions and spines of the scapulae Superiorly, the II fascia is attached to the • Superior nuchal line of occipital bone • Mastoid processes of temporal bones • Inferior border of the mandible • Hyoid bone Superior to the hyoid bone II fascia is divided into two layers (superficial and deep), forming a sheath for the submandibular gland (saccus hyomandibularis). The deep layer is attached to the internal surface of the mandible; the superficial layer is attached to the external surface and traverses superiorly till zygomatic arch as fascia parotideo-masseterica. A.v. facialis (vein lies superficially and the artery underlies the gland), lymphatic nodes are situated here. III fascia is lamina profunda fasciae colli propriae or aponeurosis omoclavicularis PNA(lamina pretrachealis f. cervicalis). It is extending between omohyoid muscles and it’s present as a layer only in the anterior part of the neck. This fascia contains the infrahyoid muscles (omohyoid, sternohyoid, sternothyroid and thyrohyoid). II and III fasciae are attached to each other by medial cervical line to form linea alba colli which extends from the hyoid bone inferiorly up to 3-4 cm not reaching the incisura jugularis of manubrium. The III fascia is attached • Superiorly to the hyoid bone • Inferiorly to the posterior surface of the manubrium and clavicles

IV fascia is endocervical fascia (PNA vagina carotica), which is divided into two layers (parietal and visceral). Visceral layer surrounds the thyroid gland, trachea, pharynx and esophagus. Parietal layer surrounds these structures only anteriorly and laterally. Laterally, it covers carotid bundle, which includes: anteriorly and medially - common carotid artery posteriorly and laterally - internal jugular vein between them and posteriorly- vagus nerve IV fascia extends from the base of the head till superior mediastinum. V fascia is prevertebral fascia (PNA lamina praevertebralis f. cervicalis), which forms a tubular sheath for the vertebral column and the muscles associated with it. The prevertebral fascia extends from the base of the skull to T3 vertebra. It covers m.m. scaleni (anterior, media et posterior), m.levator scapulae , splenius capitis and colli., a.v.subclavia, plexus brachialis.

Interfascial Spaces and Fatty Tissue of the Neck Interfascial spaces are divided into two groups: interfascial spaces connected with other regions and those, which are not connected. Not connected spaces 1. Saccus hyomandibularis lies between two layers of the II fascia and encloses the submandibular gland, facial vessels (vein lies superficially to the gland and artery underlies it) fat and a few lymph nodes which collect lymph from the oral cavity. We can palpate these nodes when the patient has inflammations in the oral cavity. 2. Spatium sternocleidomastoideum lies between two layers of the II fascia and encloses SCM. From inner side it pierces by vessels and nerves. 3. Spatium interaponeuroticum suprasternale lies between the II and III fasciae and encloses the jugular venous arch, fat and a few lymph nodes. The jugular venous arch is an anastomosis between anterior jugular veins. Laterally it is connected with spatium retrosternocleidomastoideum. 4. Spatium retrosternocleidomastoideum lies between the II and III fasciae posterior to the SCM and encloses the inferior ends of the anterior jugular veins, fat and lymph vessels. 5. Spatium interaponeuroticum supraclaviculare lies between the II and III fasciae and continuous superiorly till the omohyoid muscle. 3, 4 and 5 spaces are connected each other and during inflammation is discribed the inflammation collar. Connected spaces 1. The carotid sheath (spatium vasoneurorum) is formed by the parietal layer of the IV fascia. It extends from the base of the skull to the root of the neck and contains the • Common carotid artery • Internal jugular vein • Vagus nerve Artery lies a little medially, vein is laterally, nerve lies between the artery and the vein a little posteriorly. Except these structures, it contains deep lymph nodes, carotid sinus nerve and sympathetic fibres. If the patient has pus or blood in this space, it can spread into the superior mediastinum. 2. Spatium praeviscerale lies between parietal and visceral layers of the IV fascia. It encloses fat, plexus venosus thyroideus impar, inferior thyroid veins. The previsceral space may contain thyroid ima artery in 10-12 % of cases. High arterial pressure exists in the thyroid ima artery as it begins from the arch of aorta or brachiocephalic artery. The artery supplies the isthmus of the thyroid gland and isn’t attached to the fascia. Depending on this, when the artery is damaged, it reduces and bleeds into the superior mediastinum. We don’t know about it, because bleeding is not visible in the area of the wound and we can’t help the patient. The patient can die. The previsceral space opens inferiorly into the superior mediastinum. 3. Spatium retroviscerale lies between the IV and V fasciae. It is the largest and most important interfascial space in the neck. It is potential space consisting of loose connective tissue which may contain pus. The retrovisceral space is limited superiorly by the base of the skull and laterally on each side by the carotid sheath. It opens inferiorly into the superior mediastinum and superiorly to the retropharyngeale space and pus can spread into them.

The Superficial Veins and Nerves of the Neck The superficial veins of the neck have very important peculiarities. If the superficial veins of the neck are damaged, the air embolism can develop. The superficial veins have the following peculiarities: • The veins don’t have any valves. • The veins are situated near the chest and heart (they have negative pressure). • Adventitia of the veins is attached firmly to the superficial fasciae (because of this veins cannot constrict). The superficial veins of the neck lie between the I and II, and the II and III fasciae. They are external jugular veins, anterior jugular veins, jugular venous arch and median cervical vein (it may be absent). Damages to these veins are very dangerous for patient’s life. If more than 10.0 cm3 of air passes into the vein, the embolism of the pulmonary artery develops, because of which the patient can die. 1. The external jugular vein is projected by line from the angle of mandible to the midpoint of clavicle, is situated between the I and II fascias. 2. The anterior jugular vein is situated between the I and II fascias and is projected by the anterior margin of SCM. The right and left vein connect and form arcus venosus juguli between the II and III fasciae. 3. The median cervical vein if it is one it is projected by the midline of the neck, if two – to the sides of the midline The superficial nerves of the neck are the nerves of cervical plexus C1-C4: lesser occipital nerve, greater auricular nerve, transverse cervical nerve, supraclavicular (medial, intermedial and lateral) nerves. The lesser occipital nerve is projected by line from the midpoint of the posterior margin of the SCM to the apex of mastoid process. The greater auricular nerve is projected by line from the midpoint of the posterior margin of the SCM to the angle of the mandible. The transverse cervical nerve is projected from the midpoint of the posterior margin of the SCM horizontally forward, then subdivided into the superior branch, which with the r.colli n. facialis are formed arcus cervicalis superficialis and inferior branch – to the jugular incisures. The supraclavicular (medial, intermedial) are projected by line from the midpoint of the posterior margin of the SCM to the medial 1/3 of the clavicle and the supraclavicular lateral nerves from the same point to the acromeon. Submandibular Triangle (trigonum submandibulare) Superior border is the inferior margin of the mandible. Anterior and posterior borders are anterior and posterior bellies of m.digastricus. Layers are: 1. The skin is thin, movable. 2. The subcutaneous fat well developed and sometimes formed the second chin in fat persons. Nerve supply of the skin is from r.colli n. facialis and r.superior n.transversus colli, which are joined here forming arcus cervicalis superficialis. R.marginalis mandibulae (n.facialis) is also situated in subcutaneous fat above this arch. 3. The superficial fascia forms the vagina for m.platysma. Platysma covers the most surface of this triangle except superiolateral angle. 4. The superficial sheet of the proper fascia (lamina superficialis fasciae colli propria), the second fascia - (by Shevkunenko) forms a saccus caecus hyomandibularis for submandibular gland with its two layers: superficial, which attaches to the lower mandibular margin covers the gland anteriorly and deep, which is fixed above-to the linea mylohyoidea mandibulae, covers it posteriorly as well. Thus, upper part of the anterior glandular surface directly adjoins to the mandibular periosteum in the region of the submandibular depression (fovea submandibularis). Inferiorly at the level of the hyoid bone superficial and deep sheets of the fascia join to each other, enclosing the glandular capsule (sheath), and form not connected cellular space of the neck. It communicates only with the oral cavity by the submandibular duct. Submandibular salivary gland (glandula submandibularis) is a paired organ and lies in the same called triangle, filling the space between anterior and posterior bellies of the digastrics muscle (m. digastricus) and the mandible. The coach of the gland consists of muscles which form the floor (fundus) of the submandibular triangle: m.mylohyoideus et m.hyoglossus, covered by the 2-nd fascia of the neck, and the mandible. The gland has got two processes, which are out of the borders 3 of the glandular floor. The posterior process turns under the lower mandibular margin up to the place where medial pterygoid muscle attaches to the margin. The anterior process accompanies the submandibular duct and together with it passes into the fissure between mylohyoid and hyoglossal muscles. Sometimes it can reach to the sublingual gland which lies under the mucous membrane of the floor of the oral cavity – on the superior surface of the mylohyoid muscle. The submandibular duct (ductus submandibularis s. Whartoni – BNA) has approximately 5cm length, starts from the inner surface of the gland, then turns anteriorly and superiorly, penetrating into the fissure between m.mylohyoideus and m.hyoglossus. After that duct passes forwards by the medial side of the sublingual gland to the lingual frenulum (frenulum linguae), where it opens at the sublingual caruncle (caruncula s. papilla sublingualis) together with the greater sublingual duct (ductus sublingualis major s. Bartolini). Below the submandibular duct into this fissure also penetrates n.hypoglossus and v.lingualis, above the duct – a.lingualis. By the direction of the lingual vessels, duct and the intermuscular fissure pus can easily spread to the submandibular triangle and back, in case of phlegmones of the floor of the oral cavity. Posteriorly the submandibular gland is neighbouring to the a.carotis externa and v.jugularis interna. Between the internal surface of the gland, covered by the deep sheet of the 2-nd fascia and m.hyoglossus, pass: -v.lingualis -n.hypoglossus -n.lingualis -n.mylohyoideus As distinct from the parotid gland, interlobular dense septas which are from fascial sheets (which form the coach of the submandibular gland) inside of the gland are absent and gland can be easily separated from its fascial capsule in a blunt way. In the fascial capsule of the gland, besides the gland, also are present lymph nodes, facial artery and vein. Facial vein lies superficially and facial artery underlies the gland. At the posterior border of the triangle v.facialis joins the anterior branch of the retromandibular vein and form the common facial vein (v.facialis communis). The submandibular lymph nodes lie on the surface of the submandibular gland and in its thickness, and they are subdivided into 3 groups: anterior, posterior, inferior. They drain the lymph from the nose, medial angle of the eyelids, tongue, gums, teeth, lips and mucous membrane of cheek into the deep cervical lymph nodes. Necessity to remove not only the lymph nodes, but also the gland in case of metastasis of malignant tumors, for example, cancer of the lower lip, is conditioned with the presence of lymph nodes in the thickness of the gland. In case of inflammatory processes on the inner side of the lower eyelid submandibular lymph nodes enlarge. A.facialis arises from a.carotis externa at the level of the big horn of the hyoid bone (os hyoideum) or at the level of the mandibular angle. In the carotid triangle it gives: -a.palatina ascendens, to supply the palatine tonsil, turns to the mandible, passing in the submandibular triangle inside of the glandular fascial capsule firstly by the deep, then by the superior surface of the submandibular gland. Here facial artery gives glandular branches (rami glandulares) and at the inferior border of the mandible it (a.facialis) gives off a.submentalis (submental artery) which runs to the submental triangle, passing parallel to the mandibular margin with corresponding vein and the mylohyoid nerve (the branch of n.alveolaris inferior). Upon which facial artery, bending around the mandibular margin and passes onto the lateral surface of the face. Factually facial artery and vein become anatomical way of spreading for pus from the neck region up to the lateral facial surface. It’s obvious, that gland externally and internally is surrounded with big vessels, that’s why in case of its’ extirpation. 5. The muscular layer is presented by two layer: The superficial – m.digastricus, m.stylohyoideus The deep layer - m.mylohyoideus and m.hyoglossus. N.hypoglossus passes to the oral cavity between these two muscles. Lingual vein is situated on and lingual artery under the hyoglossus muscle. A.lingualis is situated between m.hyoglossus and lying deeper m.constrictor pharyngis medius, behind which mucous membrane of the pharynx is present. Hence in case of exposure of the artery (a.lingualis) is necessary to work carefully, because mucous membrane may be damaged and pharynx will be penetrated, thus operation field will be infected from the mucous membrane side.

The Pirogov’s triangle is described in the submandibular triangle which is visible in the position when head is thrown backwards and strongly rotated to the opposite side, and the gland is removed off the capsule and pulled upwards. Pirogov’s triangle is bounded anteriorly by the posterior free margin of the m.mylohyoideus, posteriorly by the posterior belly of the m.digastricus, superiorly by the n.hypoglossus and the v.lingualis. The floor is formed by the m.hyoglossus under which the a.lingualis is situated. In the surgical practice this triangle is used for the ligature of the lingual artery inside of the triangle in case of profuse lingual haemorrage for the permanent arrest of the bleeding.

Submental triangle (trigonum submentale) The submental triangle is unpaired. Boundaries of the triangle are: -laterally from two sides – anterior bellies of the digastrics muscles (venter anterior m.digastrici) -posteriorly – the hyoid bone (os hyoideum) Layers: 1. Skin is thin and movable. In men it’s covered by hair. 2. Subcutaneous fatty tissueis well developed. 3. Superficial fascia (1-st fascia by Shevkunenko) forms a capsule (sheath) for m.platysma. At the top of the triangle right and left fascicule (fibres) of m.platysma lie on each other. Close to the hyoid bone submental triangle is free of m.platysma and is covered by the superficial fascia. 4. Superficial sheet of the proper fascia (2-nd fascia of the neck) forms sheaths(capsules) for the anterior bellies of m.digastricus. 5. Muscles are located layerwise. Fibres of the mylohyoid muscles form suture (raphe) along the median line of the neck (linea mediana colli), which looks like a thin dense strip. Thus, fibres of the mylohyoid muscles phuse to each other by the middle line and form the oral diaphragm (diaphragma oris), which is the floor of the oral cavity. In the fat pad between 2-nd fascia and mylohyoid muscle (sometimes over the 2-nd fascia), are localized 1-2 submental lymph nodes (nodi lymphatici submentales). They drain lymph from the tongue, middle compartment of the oral cavity and of the lower lip. Geniohyoid muscles (mm.geniohyoidei) are round-shaped and are situated under the mylohyoid muscle, after that deeper to them – m.genioglossus, which passes fan-like from the mental spine up to the root of the tongue (radix linguae). Anteriorly and posteriorly to m.genioglossus adjoins m.hyoglossus, at the external surface of which are located the sublingual salivary gland and the lingual nerve (n.lingualis). This nerve turns to the tongue through the space between m.genioglossus and m.hyoglossus. From the side of the floor of the oral cavity the genioglossal muscle and the sublingual gland are covered with the mucous membrane, which is separated from them by the loose fat tissue layer. Submental artery (a.submentalis) is the branch of the facial artery (a.facialis,), together with the corresponding vein passes from the submandibular to the submental triangle in the space between the anterior belly of the digastric and mylohyoid muscles, locating closer to the mandible. Here n.mylohyoideus, which arises from the lower alveolar nerve (n.alveolaris inferior) at the place where it enters the mandibular opening (foramen mandibulare), joins to the vessels. By the inner surface of the mandible, below the place of attachment of m.mylohyoideus, the mylohyoid nerve (n.mylohyoideus) penetrates into the submental triangle, innervating the samely called muscle and the anterior belly of the digastric muscle (m.digastricus). Infection to the submental region can spread from the lower incisival and canine teeth – dentes incisivi et canini (odontogen way). Infection from the submental region can spread by the direction of the inflammatory process from the submandibular and infraorbital regions, and also by the direction of the lymphatic vessels (lymphatogen way).

Carotid Triangle (trigonum caroticum) This triangle bounded by the sternocleidomastoid muscle (SCM) laterally, posterior belly of digastric muscle superiorly and the superior belly of omohyoid muscle inferiorly. 1. The skin is thin, movable with superficial fascia and platyzma, with which it fuses.

Platyzma covers this triangle completely. Under the platyzma and on the II fascia r.colli n.facialis, r.superior n.transversus colli and v.jugularis anterior are situated in the fat. 2. II fascia by Shevkunenko is represented in one layer. 3. Under this fascia the neurovascular bundle of the medial triangle of the neck is situated. Internal jugular vein, the carotid arteries with it’s branches, the vagus nerve with it’s n.laryngeus superior (the last one gives off n. thyroideus superior) are situated covered by lamina parietalis f.endocervicalis by Shevkunenko, IV fascia(vagina carotica, PNA). This fascial sheath encloses the neurovascular bundle, deep lymph nodes, which accompany the internal jugular vein and fat. Carotid artery lies medially, internal jugular vein lies laterally, n.vagus is between them and posteriorly. Carotid common artery is projected by bisector of the angle between the SCM and m.omohyoideus. The common carotid artery is divided at the level of the upper border of the thyroid cartilage or greater horn of hyoid bone into internal and external branches. Usually external carotid artery is situated superficially and medially to internal. The internal carotid artery has no branches on the neck in this triangle. The external carotid artery gives off 7 branches in carotid triangle. 1. The superior thyroid artery, which gives off superior laryngeal artery. 2. The lingual artery. 3. The facial artery, which arises above the lingual one and gives off ascending palatine artery, which supplies the palatine tonsil. 4. The occipital artery. 5. The sternocleidomastoid artery. 6. The posterior auricular artery. 7. The ascending pharyngeal artery. In the carotid triangle hypoglossal nerve gives off the superior root of ansa cervicalis, which descends lying on the internal and common carotid arteries and joins the inferior root from cervical plexus. As a result a loop is formed called ansa cervicalis which supplies the infrahyoid muscles (sternohyoid, sternothyroid, thyrohyoid and omohyoid). The deep cervical lymph nodes are situated around the internal jugular vein and form the jugular lymph trunk. The facial vein enters the carotid triangle over the posterior belly of digastric muscle. The internal jugular vein descends vertically first with the internal then with the common carotid artery. In front from the common carotid bifurcation in internal jugular vein drains the common facial vein, which form by connection of: v.facialis v.thyroidea superior v.laryngea superior v.lingualis r.anterior v.retromandibularis At the place of common carotid bifurcation is located the sinocarotic reflex zone, which forms vagus, glossopharyngeus nerves and sympatethic branches. From the zone arises the sinocarotic nerve, which goes to the brain as component of the glossopharyngeus nerves. The baroreceptors of this zone regulate the arterial blood pressure. Behind the common carotid bifurcation is situated the glomus caroticus, which contain the chemoreceptors. They are sensitive to the hyperoxygenation and hypercarbodioxygenation of blood. 4. After vagina carotica is coming the V facsia, which is covered the cervical part of the sympathetic trunk. The common carotid artery is projected by line, which connects the midpoint of mandibular angle and mastoid process with the sternoclavicular joint to the right and with the midpoint of SCM muscle both legs (cruras).

Omotracheal Triangle (trigonum omotracheale) This is the space under the hyoid bone bounded by the sternocleidomastoid laterally and superiorly by superior belly of omohyoid. The median plane divides it into left and right omotracheal triangles. 1. The skin is thin, moveable. 2. The subcutaneous tissue is loose connective tissue. 3. Superficial fascia with platysma. Platysma covers only supero-lateral surfaces of the triangle, in the midline it is absent. Under this fascia is situated the transverse coli nerve with it’s branches and anterior jugular vein. The vein pierces the II fascia and form the anastomosis. 4. II fascia by Shevkunenko, superiorly attaches to the hyoid bone, inferiorly to the anterior margin of jugular notch. With III fascia in the upper half of this distant it forms the linea alba. In lower half spatium interaponeuroticum suprasternale which is situated between the II and III fasciae and where located an anterior jugular veins anastomosis called jugular venous arch (arcus venosus juguli). 5. III fascia encloses the infrahyoid muscles. The altitude of the spatium interaponeuroticum suprasternale is 3-4 cm, above which the II and III fasciae combine and form linea alba cervicis. 6. Parietal and visceral layers of the IV fascia by Shevkunenko. Between the parietal and visceral layers of endocervical fascia the previsceral space is situated, which contains fat, lymph nodes, plexus venosus thyroideus impar, inferior thyroid veins and in 10-12% of cases- thyroid ima artery. The cervical organs are situated deeper and are covered by visceral layer of endocervical fascia (IV). Here larynx and trachea are situated, deeper- pharynx and esophagus, superficially and laterally - thyroid lobes with parathyroid glands on their postero-medial surfaces. 7. V fascia by Shevkunenko covered the anterior surfaces of the vertebral bodies. Retrovisceral space is situated between the endocervical (IV) and prevertebral (V) fasciae. The thyroid gland. The isthmus of thyroid gland is situated at the level of 2-4 tracheal cartilages. In front from lobes are situated the sternothyroid, sternohyoid, omohyoid muscles. Laterally and posteriorly to the lobes are faced common carotid arteries and internal jugular veins. The gland is surrounded the trachea and pharynx, from the left also esophagus. Besides the visceral layer of the IV fascia the gland also directly is covered (by Kornig) by fibrous capsule. Between this two coats posteromedialy from the lobes the parathyroid glands are present. The fascial coat of gland is formed two ligaments for fixation the gland. The middle one stretches from the isthmus of the gland till cricoid cartilage, the lateral ones from the lobes to the cricoid and thyroid cartilages. The isthmus become movable only after cutting these ligaments. The gland is supplied by superior and inferior thyroid arteries and in 10-12% also by thyroid ima artery to the isthmus. The veins form the plexus, from which arises the inferior and superior thyroid veins. The superior thyroid vein participates in formation of the common facial vein, the inferior thyroid vein drains into the brachiocephalic veins (innominate veins). From the plexus thyroideus impar blood goes to the left innominate vein. Sympathetic innervation is from the upper cervical ganglion of the sympathetic trunk. Parasympathetic innervation is from the n.thyroideus superior and n.laryngeus reccurens (n.vagus). At the inferior margin of thyroid gland in front from n.laryngeus reccurens runs the inferior thyroid artery. During non complete (subtotal) strumectomia the n.laryngeus reccurens can be incorrectly ligatured, which can lead to dysphonia. The trachea. The trachea is located by midline. Cervical part of the trachea is presented by 6-8 semicircular cartilaginous rings, which posteriorly are replaced connective tissue layer and smooth musculature. Inside is covered by ciliary epithelium. The cervical part of trachea starts from the C6 vertebra and continuous till Th2-3 vertebra. Laterally and superiorly trachea is faced to the lobes of thyroid gland, inferiorly – to the common carotid arteries. The isthmus of thyroid gland is situated at the level of 2-4 tracheal cartilages. Posteriorly from the trachea - is esophagus. To the external surface of the body the trachea is located in different depth. It’s beginning in 1,5-2 cm deeply from the skin surface, at the level of jugular notch – 4cm, at the level of bifurcation - 6-7 cm. This fact has a clinical importance. Inferior thyroid artery supplies the cervical part of the trachea. Sympathetic innervations – from sympathetic trunk. Parasympathetic innervations - is from recurrent laryngeal nerve of the vagus.

The esophagus. Cervical part of the esophagus 4-6 cm. It situated posteriorly and to the left from the trachea. The cervical part of it starts from the C6 vertebra and continuous till Th2-3 vertebra. In front from the esophagus is the trachea (between them is connective tissue), laterally in the groove there is the recurrent laryngeal nerve and common carotid arteries. Behind the esophagus is the vertebral column with m.longus colli and capitis. Left carotid artery is in distance 0,3-0,5 cm from the esophagus, the right one – 1 -1,5 cm. The esophagus has 2 physiological constriction on the neck. Superior or pharyngeal constriction at it’s beginning and the aortic constriction (it is related with aorta). Inferior thyroid artery supplies the cervical part of the esophagus. Sympathetic innervations – from sympathetic trunk. Parasympathetic innervations - is from recurrent laryngeal nerve of the vagus. Sternocleidomastoid Region (regio sternocleidomastoideus) Sternocleidomastoid region is located between the medial and lateral triangles of the neck, and coincides with location of the SCM muscle. 1. The skin in superior third of the region is thick, unmovable, but in inferior two thirds it’s thin and movable. Platysma covers only medial third of this region. 2. II fascia by Shevkunenko which forms a sheath for SCM muscle. External jugular vein, superficial lymph nodes and branches of cervical plexus are situated on the SCM. External jugular vein begins behind the angle of the mandible by the junction of the posterior branch of the retromandibular vein with the posterior auricular vein. It passes vertically downwards and pierces the II, III and V fasciae (by Shevkunenko) at the posterior border of the SCM above the clavicle and drains into the subclavian vein. As we know adventitia of the vein is attached firmly to the fascia, because of this, the vein cannot constrict and air embolism may develop, if it’s injured. The branches of cervical plexus are n. auricularis magnus, n. transversus colli, n. occipitalis minor, n.n. supraclavicularis medialis, intermedius et lateralis. 3. Under the inferior third of SCM, inferiorly to the omohyoid muscle saccus caecus retrosternocleidomastoideus takes place between the II and III fascia by Shevkunenko. 4. V fascia by Shevkunenko. Deeper, under the prevertebral fascia, scaleno-vertebral triangle is described. The base of this deep triangle is copula of pleurae - apex of the lung, medial border is vertebral column with longus colli, lateral border is anterior scalenus muscle. The top of this triangle is tuberculum caroticum of the transverse process of the VI vertebra. I part of subclavian artery, brachiocephalic veins, ganglion cervico- thoracicum (g. stellatum) and thoracic duct (in the left side) or right lymphatetic duct are situated in this triangle. The left subclavian artery arises from the arch of aorta; the right subclavian artery arises from the brachiocephalic trunk. Each artery may be divided into three parts. First part is situated on the cervical pleura (in the scaleno-vertebral triangle) medial to scalenus anterior. The second part is behind it (in spatium interscalenum) and the third part is lateral to it (in omoclavicular triangle). It ends at the outer border of the first rib behind the midpoint of the clavicle. The branches of the first part of subclavian artery are: 1. a. vertebralis 2. a. thoracica interna 3. truncus thyreo-cervicalis, which gives rise to; a) a. thyroidea inferior b) a. cervicalis ascendens c) a. cervicalis superficialis d) a. suprascapularis From the second part of subclavian artery truncus costo-cervicalis arises, which gives off: a) a. cervicalis profunda b) a. intercostalis suprema (for I and II intercostal spaces) From the third part of subclavian artery a. transversa colli arises. Each brachiocephalic vein begins by a junction of internal jugular and subclavian veins which is called venous angle. The thoracic duct enters the posterior surface of the venous angle from the left side. The thoracic duct is a thin-walled vessel, which collects the lymph from the whole body except the right anterior thoracic wall, upper 8 limb, right side of the neck and the head. The lymph from these parts of the body is collected by the right jugular and clavicular lymph trunks which open into the right venous angle.

Lateral Cervical Triangle (trigonum colli laterale) Bounderies of this region are: anteriorly – posterior border of the SCM posteriorly – anterior border of the trapezoid muscle inferiorly – superior surface of the clavicle This triangle is subdivided into two triangles by the posterior belly of the omohyoid muscle (superiorly is omotrapezoid, inferiorly – omoclavicular triangles). 1. The skin is thin, without hair, movable with subcutaneous tissue. 2. Next layer is superficial fascia (I fascia by Shevkunenko) with platyzma. 3. II fascia by Shevkunenko is perforated by the branches of the cervical plexus at the level of the posterior border of the SCM. There are n.auricularis magnus, n.transversus colli, n.occipitalis minor, n.n.supraclaviculares medialis, intermedius et lateralis. 4. Next layer is V fascia by Shevkunenko in the omotrapezoid triangle. N.accessorius is located between II and V fasciae. In omoclavicular triangle after the II fascia, the III fascia is present, then the V fascia. There the scalenal spaces are described. Spatium antescalenum is limited: anteriorly by the clavicle, posteriorly – m.scalenus anterior. V.subclavia and n.phrenicus (between V fascia and scalenus anterior muscle) pass through this space. Spatium interscalenum is limited: anteriorly by the m.scalenus anterior, posteriorly by the m.scalenus medius, inferiorly – anterior surface of the first rib. A.subclavia and plexus brachialis are situated in this space.

TOPOGRAPHIC ANATOMY OF THE THORAX The thorax extends between the neck and abdomen. The superior boundary of the thorax is the superior margin of manubrium sterni and clavicles, an imaginary line which extends between acromions and spinous process of the 7-th cervical vertebra. The inferior boundary is the xiphoid process, costal arches (arcus costae), and free ends of the 11th and 12th ribs, inferior margin of 12-th pair of ribs till spinous process 12-th thoracic vertebra. The thorax consists of the thoracic wall and cavity. The thoracic cavity includes 4 cavities (1 fibrous, 3 serous) the mediastinum is fibrous and pleural, pericardial cavities are serous. The wall consists of so called movable and own layers. We describe several imaginary lines on the thoracic wall. It is necessary for the description of wounds and organs, which are situated in the thoracic cavity. We use the following imaginary lines (all of these lines are parallel to each other): 1. Linea mediana anterior passes through the midline of the sternum. 2. Linea sternalis passes through the lateral margin of the sternum. 3. Linea medioclavicularis passes through the middle point of the clavicle. 4. Linea parasternalis passes through the middle point of the distance between linea sternalis and linea medioclavicularis. 5. Linea axillaris anterior begins from the inferior border of the m. pectoralis major. 6. Linea axillaris posterior begins from the inferior border of the m. latissimus dorsi. 7. Linea axillaris media passes through the middle point of the distance between linea axillaris anterior and linea axillaris posterior. 8. Linea scapularis passes through the inferior angle of the scapula. 9. Linea vertebralis passes through the lateral margins of the thoracic vertebrae. 10. Linea paravertebralis extends in the midpoint of the distance between linea vertebralis and linea scapularis. 11. Linea mediana posterior passes through the spinous processes of the thoracic vertebrae. The thorax is divided into anterior and posterior parts by a plane, which traverses through the middle axillary lines. By means of the sternal and vertebral lines, the thorax is divided into the following regions: 9

1. Regio sternalis. 2. Regio vertebralis. 3. Regio thoracalis anterior superior and inferior. The border between these 2 regions is an imaginary line, which passes through the inferior margin of the 5th pair of ribs (or inferior margin of m. pectoralis major). 4. Regio thoracalis posterior superior and inferior. The border between these regions is an imaginary line, which passes through the inferior angles of the scapula. The so-called movable layers are the same in all regions, such as the skin, fatty tissue, fasciae and muscles with their peculiarities in each region. The own layers include the bones of the thorax (vertebrae, sternum, ribs), the intercostal muscles, the thoracic transverse muscle and f. endothoracica. In topographic anatomy of the chest the anterior superior thoracic region interests us most of all, because the breast containing mammary gland is situated here.

Cricoconicotomy

Cricoconicotomy is an emergency operation according to vital indications. Cricoconicotomy is an opening of the lumen of the larynx at the level of : -cricoid cartilage – cricotomy -thyreo-cricoid (conic) cartilage – conicotomy. This operation differs in simplicity of performance due to the superficial location of the above mentioned structures, on the way to which vessels are absent. Indications: Severe respiratory insufficiency – when there’s no time to provide the tracheostomy and time to keep viability of the cerebral cortex. The reasons of the severe respiratory insufficiency, as usual, is trauma of the larynx and obturation of its’ lumen by a foreign body. Technique: Median incision of the skin – from the border between the middle and lower thirds of the thyroid cartilage up to the incisura jugularis. After cutting the all tissues layer-by-layer, expose the conic ligament and the cricoid cartilage. After cutting them, provide access of air into airways. As it’s the temporary measure which is carried out for the purpose of preservation of life of the patient, further intake of air in airways is provided with the subsequent tracheostomy. Necessity of the tracheostomy arises because situation of the cannula inside of the cricoconicostoma can cause such complications as sweeling of cellular pad and decubituses of the subvoice cavity of the throat, chondroperichondritis, with subsequent stenosis of the throat, and also cicatricial deformation (stricture), arthritis of the arythaeno-cricoid joints.