DOCSLIB.ORG

LOCAL ANESTHESIA “Surgical Anatomy”

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
LOCAL ANESTHESIA “Surgical Anatomy” Local anesthesia “Surgical anatomy” 1 The Anatomical Basis of Dental Pain Impulses originating in the nerve-endings of the dental pulp and the supporting structures of the teeth are conveyed to the central nervous system by the second (Maxillary) and the third (Mandibular) divisions of the fifth cranial or trigeminal nerve. From cell bodies in the Gasserian ganglion these neural pathways pass to the sensory nucleus of the trigeminal nerve which is situated in the medulla oblongata and extends to the level of second cervical segment of the spinal cord. Then they pass via the trigeminal lemniscus to the thalamus and then to the cortex of the brain. Interruption of theses neural pathways at any level abolish the sensation of pain. The only nerve with which the dental surgeon is concerned when administrating a local analgesic is the trigeminal nerve (5th cranial nerve), which is the largest of the cranial nerves. 2 This nerve has a big sensory and smaller motor roots. It supplies the mandible, maxilla, and associated structures, and also most of the skin of face. The motor branch supplies all muscles of mastication (the temporalis, masseter, medial pterygoid, and lateral pterygoid muscles) but not the buccinator, which is considered to be a muscle of facial expression, being innervated by the facial nerve (7th cranial nerve). 3 THE OPHALMIC , OR FIRST DIVISION OF THE TRIGRMINAL NERVE Ophthalmic nerve, which is entirely sensory, is of little interest to the dental surgeon. It divides into three main branches which pass into the orbit through the superior orbital fissure. These are: 1. The frontal nerve 2. The nasociliary nerve 3. The lacrimal nerve. 1. The frontal nerve. This supplies the forehead and the scalp as far back as the vertex. It also supplies the skin at the root of the nose, the skin and conjunctiva of the upper eyelid, and the mucosal lining of the frontal sinus. 2. The nasociliary nerve. This supplies the cornea and sclera of the eye, the upper and anterior part of the nasal septum, and the lateral wall of the nose. 3. The lacrimal nerve. This is the smallest of the branches. It supplies the gland of the same name (the lacrimal gland), It also supplies part of the conjunctiva. THE MAXILLARY, OR SECOND DIVISION OF THE TRIGEMINAL NERVE Maxillary division is entirely sensory. It supplies the whole of the maxilla including the teeth and their gingiva, the maxillary sinus, and the mucous membranes of the hard and soft palates, the nasal cavity and the nasopharynx, in addition it innervates the skin of the upper lip, the upper part of the cheek, the lower eyelid, the skin over the adjacent part of the nose, the skin over the anterior part of the temporal region, and that overlying the zygomatic bone. 4 Through the sphenopalatine ganglion pass the following main branches: Branch to the orbit. The short sphenopalatine nerves reach the nose via the sphenopalatine foramen. They supply the upper and posterior part of the lateral wall of the nose. 5 3. The long sphenopalatine (nasopalatine) nerve passes along the septum, which it supplies, to the floor of the nasal cavity, and then through the incisive canal to emerge at the incisive fossa on to the palate. It supplies the mucoperiosteum, gingiva and alveolar process and the anterior part of the palate from canine to canine. 4. The greater palatine nerve gains the palate by passing through the greater palatine foramen which is situated medially to the second or third molar. It supplies the mucoperiosteum and gingivae of the hard palate from the canine posteriorly and rarely may supply the palatal root of the maxillary first and second molars. This explains why there are occasions when maxillary molars remain sensitive after buccal infiltration have been given and analgesia is not obtained until additional palatal infiltrations have been administrated. 6 5. The lesser palatine nerves traverse the lesser palatine foramina of the hard palate to innervate the mucosa of the soft palate and the uvula. The palatine nerves (greater and lesser) together supply the whole of the sensory innervation to the mucosa covering the hard and soft palates and also propagate secretory and taste fibres to this region. 6. A small pharyngeal branch passes from the ganglion to reach the nasopharynx. THE MANDIBULAR, OR THIRD DIVISION, OF THE TRIGEMINAL NERVE This division of the trigeminal nerve is both sensory and motor, supplying all the muscles of mastication. The sensory part innervates the whole of the lower jaw including the teeth and their associated gingivae, the skin overlying the chin, the skin and mucous membrane of the lower lip and part of the cheek, and the anterior two-thirds of the tongue, except for the cicumvallate papillae. 7 BRANCHES • Meningeal branch (nervus spinosus) • Nerve to medial pterygoid • Anterior trunk: Masseteric nerve Deep temporal nerves Nerve to lateral pterygoid Buccal nerve • Posterior trunk: Auriculotemporal nerve Lingual nerve Inferior alveolar nerve 8 9 Neurophysiology Nerves are groups of cells that act together to be a communication system for the Central Nervous System (CNS). The neuron is the cell responsible for transmitting messages from the periphery of the body to the CNS and from the CNS to the periphery of the body. Afferent or sensory nerves conduct impulses to the CNS while efferent or motor neurons conduct messages from the CNS to the periphery. The sensation of pain is first felt at the skin, tissue, or mucosa and the dendritic zone (made up of free nerve endings) starts the impulse. This impulse follows along an axon to the brain where it is interpreted. After the sensory nerve stimulates the CNS, the CNS decides the best action to take and sends its decision via impulse back through motor neurons to activate muscles. The axon is a long nerve fiber that runs the whole length of the nerve. It's encased in a nerve membrane called an axolemma. Inside the membrane is a gelatinous substance called axoplasm. Most axolemmas are surrounded by a myelin sheath. 11 The most widely held theory on nerve transmission attributes conduction of the nerve impulse to changes in the axolemma, not necessarily the axoplasm or the cell body. In a resting nerve, the electrical resistance keeps sodium, potassium and chloride ions from flowing into the axoplasm. Nerves have a resting potential where the inside or axoplasm has a negative electrical potential. When the nerve is stimulated, the electrical potential is slightly decreased (slow polarization). Then at a certain level of electrical potential called the threshold potential or firing threshold, a rapid depolarization of the membrane occurs. The electrical potential is then reversed resulting in the inside of the nerve being electrically positive and the outside negative. After depolarization, the membrane gradually polarizes again to the normal resting potential. When the nerve is stimulated and an impulse is generated, the conductivity changes and the membrane allows sodium and potassium ions to pass into the axoplasm. This provides the energy for the impulse to continue along the nerve to the CNS. 11 .
Load more

Recommended publications
  • Perioral Gustatory Sweating: Case Report
    The Journal of Laryngology & Otology (2012), 126, 532–534. CLINICAL RECORD © JLO (1984) Limited, 2012 doi:10.1017/S0022215112000229 Perioral gustatory sweating: case report S C KÄYSER1, K J A O INGELS2, F J A VAN DEN HOOGEN2 1Department of Primary and Community Care, Radboud University Nijmegen Medical Centre, and 2Department of Otorhinolaryngology/Head and Neck Surgery, Radboud University Nijmegen Medical Centre, The Netherlands Abstract Objective: Presentation of a case of perioral Frey syndrome. Design: Case report. Subject: A 72-year-old woman with hyperhidrosis around the mouth and chin. Results: This patient suffered from bilateral perioral gustatory sweating following a mandibular osteotomy; such a case has not previously been described. Possible pathophysiological hypotheses are discussed in relation to the anatomy and innervation of the salivary glands. Conclusion: Perioral gustatory sweating is a rare complication of osteotomy. Key words: Gustatory sweating; Frey Syndrome; Perioral; Hyperhidrosis Introduction perioral excessive sweating and flushing which only Frey syndrome, also known as auriculotemporal syndrome, is a occurred during (and not preceding) eating. Her complaints well-known complication of parotid surgery. Approximately had begun following bilateral osteotomy of the mandible in 24 per cent of patients undergoing parotidectomy experience 1960, at the age of 25 years. The indication for this procedure gustatory sweating, although the reported incidence varies had been prognathism. Her recovery had been complicated greatly.1 Frey syndrome appears following a latency period by inadequate bone healing and loss of the right and left of one to 36 months (or longer) after surgery.2,3 inferior alveolar nerves (Figure 1). The aetiology of Frey syndrome is explained by ‘aberrant The diagnosis of hyperhidrosis was made using the nervous regeneration’.
    [Show full text]
  • Nerves of the Orbit Optic Nerve the Optic Nerve Enters the Orbit from the Middle Cranial Fossa by Passing Through the Optic Canal
    human anatomy 2016 lecture fourteen Dr meethak ali ahmed neurosurgeon Nerves of the Orbit Optic Nerve The optic nerve enters the orbit from the middle cranial fossa by passing through the optic canal . It is accompanied by the ophthalmic artery, which lies on its lower lateral side. The nerve is surrounded by sheath of pia mater, arachnoid mater, and dura mater. It runs forward and laterally within the cone of the recti muscles and pierces the sclera at a point medial to the posterior pole of the eyeball. Here, the meninges fuse with the sclera so that the subarachnoid space with its contained cerebrospinal fluid extends forward from the middle cranial fossa, around the optic nerve, and through the optic canal, as far as the eyeball. A rise in pressure of the cerebrospinal fluid within the cranial cavity therefore is transmitted to theback of the eyeball. Lacrimal Nerve The lacrimal nerve arises from the ophthalmic division of the trigeminal nerve. It enters the orbit through the upper part of the superior orbital fissure and passes forward along the upper border of the lateral rectus muscle . It is joined by a branch of the zygomaticotemporal nerve, whi(parasympathetic secretomotor fibers). The lacrimal nerve ends by supplying the skin of the lateral part of the upper lid. Frontal Nerve The frontal nerve arises from the ophthalmic division of the trigeminal nerve. It enters the orbit through the upper part of the superior orbital fissure and passes forward on the upper surface of the levator palpebrae superioris beneath the roof of the orbit .
    [Show full text]
  • Regional Anesthesia in Head and Neck Surgery
    TITLE: Regional Anesthesia in Head and Neck Surger SOURCE: Grand Rounds Presentation, UTMB, Dept. of Otolaryngology DATE: May 24, 2006 RESIDENT PHYSICIAN: Jacques Peltier, MD FACULTY PHYSICIAN: Francis B. Quinn, MD SERIES EDITORS: Francis B. Quinn, Jr., MD and Matthew W. Ryan, MD "This material was prepared by resident physicians in partial fulfillment of educational requirements established for the Postgraduate Training Program of the UTMB Department of Otolaryngology/Head and Neck Surgery and was not intended for clinical use in its present form. It was prepared for the purpose of stimulating group discussion in a conference setting. No warranties, either express or implied, are made with respect to its accuracy, completeness, or timeliness. The material does not necessarily reflect the current or past opinions of members of the UTMB faculty and should not be used for purposes of diagnosis or treatment without consulting appropriate literature sources and informed professional opinion." Introduction Local anesthetic techniques were popularized early in the history of surgery with the advent of injectable nerve blocking agents. Until their discovery, patients were either held down or knocked unconscious to perform procedures. In the early days of general anesthesia, local anesthesia was preferred in all cases that it was applicable due to the significant risks associated with general anesthesia. Many procedures performed today under general anesthesia, such as tonsillectomy, rhinoplasty, and even bronchoscopy, were performed under local anesthesia to avoid the perils of general anesthetics. With the introduction of pulse oximetry, safer inhaled anesthetics, and combined intravenous and inhaled general anesthesia techniques, general anesthesia has become much safer, resulting in many surgeons being unfamiliar with regional nerve blocks to perform surgery.
    [Show full text]
  • Anatomy of Maxillary and Mandibular Local Anesthesia
    Anatomy of Mandibular and Maxillary Local Anesthesia Patricia L. Blanton, Ph.D., D.D.S. Professor Emeritus, Department of Anatomy, Baylor College of Dentistry – TAMUS and Private Practice in Periodontics Dallas, Texas Anatomy of Mandibular and Maxillary Local Anesthesia I. Introduction A. The anatomical basis of local anesthesia 1. Infiltration anesthesia 2. Block or trunk anesthesia II. Review of the Trigeminal Nerve (Cranial n. V) – the major sensory nerve of the head A. Ophthalmic Division 1. Course a. Superior orbital fissure – root of orbit – supraorbital foramen 2. Branches – sensory B. Maxillary Division 1. Course a. Foramen rotundum – pterygopalatine fossa – inferior orbital fissure – floor of orbit – infraorbital 2. Branches - sensory a. Zygomatic nerve b. Pterygopalatine nerves [nasal (nasopalatine), orbital, palatal (greater and lesser palatine), pharyngeal] c. Posterior superior alveolar nerves d. Infraorbital nerve (middle superior alveolar nerve, anterior superior nerve) C. Mandibular Division 1. Course a. Foramen ovale – infratemporal fossa – mandibular foramen, Canal -> mental foramen 2. Branches a. Sensory (1) Long buccal nerve (2) Lingual nerve (3) Inferior alveolar nerve -> mental nerve (4) Auriculotemporal nerve b. Motor (1) Pterygoid nerves (2) Temporal nerves (3) Masseteric nerves (4) Nerve to tensor tympani (5) Nerve to tensor veli palatine (6) Nerve to mylohyoid (7) Nerve to anterior belly of digastric c. Both motor and sensory (1) Mylohyoid nerve III. Usual Routes of innervation A. Maxilla 1. Teeth a. Molars – Posterior superior alveolar nerve b. Premolars – Middle superior alveolar nerve c. Incisors and cuspids – Anterior superior alveolar nerve 2. Gingiva a. Facial/buccal – Superior alveolar nerves b. Palatal – Anterior – Nasopalatine nerve; Posterior – Greater palatine nerves B.
    [Show full text]
  • Simple Ways to Dissect Ciliary Ganglion for Orbital Anatomical Education
    OkajimasDetection Folia Anat. of ciliary Jpn., ganglion94(3): 119–124, for orbit November, anatomy 2017119 Simple ways to dissect ciliary ganglion for orbital anatomical education By Ming ZHOU, Ryoji SUZUKI, Hideo AKASHI, Akimitsu ISHIZAWA, Yoshinori KANATSU, Kodai FUNAKOSHI, Hiroshi ABE Department of Anatomy, Akita University Graduate School of Medicine, Akita, 010-8543 Japan –Received for Publication, September 21, 2017– Key Words: ciliary ganglion, orbit, human anatomy, anatomical education Summary: In the case of anatomical dissection as part of medical education, it is difficult for medical students to find the ciliary ganglion (CG) since it is small and located deeply in the orbit between the optic nerve and the lateral rectus muscle and embedded in the orbital fat. Here, we would like to introduce simple ways to find the CG by 1): tracing the sensory and parasympathetic roots to find the CG from the superior direction above the orbit, 2): transecting and retracting the lateral rectus muscle to visualize the CG from the lateral direction of the orbit, and 3): taking out whole orbital structures first and dissecting to observe the CG. The advantages and disadvantages of these methods are discussed from the standpoint of decreased laboratory time and students as beginners at orbital anatomy. Introduction dissection course for the first time and with limited time. In addition, there are few clear pictures in anatomical The ciliary ganglion (CG) is one of the four para- textbooks showing the morphology of the CG. There are sympathetic ganglia in the head and neck region located some scientific articles concerning how to visualize the behind the eyeball between the optic nerve and the lateral CG, but they are mostly based on the clinical approaches rectus muscle in the apex of the orbit (Siessere et al., rather than based on the anatomical procedure for medical 2008).
    [Show full text]
  • Anatomical Study of the Zygomaticotemporal Branch Inside the Orbit
    Open Access Original Article DOI: 10.7759/cureus.1727 Anatomical Study of the Zygomaticotemporal Branch Inside the Orbit Joe Iwanaga 1 , Charlotte Wilson 1 , Koichi Watanabe 2 , Rod J. Oskouian 3 , R. Shane Tubbs 4 1. Seattle Science Foundation 2. Department of Anatomy, Kurume University School of Medicine 3. Neurosurgery, Complex Spine, Swedish Neuroscience Institute 4. Neurosurgery, Seattle Science Foundation Corresponding author: Charlotte Wilson, [email protected] Abstract The location of the opening of the zygomaticotemporal branch (ZTb) of the zygomatic nerve inside the orbit (ZTFIN) has significant surgical implications. This study was conducted to locate the ZTFIN and investigate the variations of the ZTb inside the orbit. A total of 20 sides from 10 fresh frozen cadaveric Caucasian heads were used in this study. The vertical distance between the inferior margin of the orbit and ZTFIN (V-ZTFIN), the horizontal distance between the lateral margin of the orbit and ZTFIN (H-ZTFIN), and the diameter of the ZTFIN (D-ZTFIN) were measured. The patterns of the ZTb inside the orbit were classified into five different groups: both ZTb and LN innervating the lacrimal gland independently (Group A), both ZTb and LN innervating the lacrimal gland with a communicating branch (Group B), ZTb joining the LN without a branch to the lacrimal gland (Group C), the ZTb going outside the orbit through ZTFIN without a branch to the lacrimal gland nor LN (Group D), and absence of the ZTb (Group E). The D-ZTFIN V-ZTFIN H-ZTFIN ranged from 0.2 to 1.1 mm, 6.6 to 21.5 mm, 2.0 to 11.3 mm, respectively.
    [Show full text]
  • Innervation of the Temporomandibular Joint Can Be Discussed It Is Necessary First to Describe Its Embryology, Gfoss Anatomy and Microscopic Appe¿Ìrance
    à8.ì 'R? INNERVATION OF THE TEMPOROMAI\DIBULAR J AN EXPERIMENTAL AMMAL MODEL USING AUSTRALIAN MERINO STIEEP ABDOLGHAFAR TAHMASEBI-SARVESTANI' B. Sc, M. Sc Thesis submitted for the degree of DOCTOR OF PHILOSOPHY In The Department of Anatomical Sciences The University of Adelaide (Faculty of Medicine)' Adelaide, South Australia, 5005 April, L997 tfüs tñesisis [elicatelø nl wtfe Aggñleñ ø¡tlour g4.arzi"e tfr.re e c friûfren Ía fiera ñ, fo zic ñ atú fi l-1 ACKNOWLEDGMENTS I am greatly indebted to my supervisors Dr. Ray Tedman and Professor Alastair Goss who first inrroduced me to this freld of study and providing me with the opportunity to carry out this work. I wish to thank them for their constant interest and guidance throughout the course of this study. I am also indebted to the scholarship committee of the Shiraz Medical Science University and Ministry of Health and Medical Education, Iran for gânting me a 4 year scholarship to study at the Universiry of Adelaide. I thank professor Goss and the Japanese Surgical Research team for their expertise in surgical animal models, and Professor July Polak and Dr Mika Hukkanen, Royal postgraduate Medical School London University for their expertise in immunohistochemistry and for providing some of the antisera used in the neuropeptide studies. I would also like to thank Professor Ian Gibbins, Department of Anatomy and Histology of the Flinders Medical Centre for, without the use of his laboratories, materials, and expertise, the double and triple labelling parts of the immunocytochemical work would not have occurred. I also orwe many thanks to Susan Matthew, a senior laboratory officer for her skilful technical assistance in double and triple immunocytochemistry.
    [Show full text]
  • The Mandibular Nerve - Vc Or VIII by Prof
    The Mandibular Nerve - Vc or VIII by Prof. Dr. Imran Qureshi The Mandibular nerve is the third and largest division of the trigeminal nerve. It is a mixed nerve. Its sensory root emerges from the posterior region of the semilunar ganglion and is joined by the motor root of the trigeminal nerve. These two nerve bundles leave the cranial cavity through the foramen ovale and unite immediately to form the trunk of the mixed mandibular nerve that passes into the infratemporal fossa. Here, it runs anterior to the middle meningeal artery and is sandwiched between the superior head of the lateral pterygoid and tensor veli palatini muscles. After a short course during which a meningeal branch to the dura mater, and the nerve to part of the medial pterygoid muscle (and the tensor tympani and tensor veli palatini muscles) are given off, the mandibular trunk divides into a smaller anterior and a larger posterior division. The anterior division receives most of the fibres from the motor root and distributes them to the other muscles of mastication i.e. the lateral pterygoid, medial pterygoid, temporalis and masseter muscles. The nerve to masseter and two deep temporal nerves (anterior and posterior) pass laterally above the medial pterygoid. The nerve to the masseter continues outward through the mandibular notch, while the deep temporal nerves turn upward deep to temporalis for its supply. The sensory fibres that it receives are distributed as the buccal nerve. The 1 | P a g e buccal nerve passes between the medial and lateral pterygoids and passes downward and forward to emerge from under cover of the masseter with the buccal artery.
    [Show full text]
  • An Unusual Finding of the Auriculotemporal Nerve: Possible Risk Factor During Preauricular Skin Incisions
    Case Report An unusual finding of the auriculotemporal nerve: possible risk factor during preauricular skin incisions Joe Iwanaga1,2,3, Samuel L. Bobek4, Christian Fisahn1,5, Ken Nakamura3, Yoshihiro Miyazono3, R. Shane Tubbs1 1Seattle Science Foundation, Seattle, WA 98122, USA; 2Department of Anatomy, 3Dental and Oral Medical Center, Kurume University School of Medicine, Kurume, Fukuoka 830-0011, Japan; 4Swedish Maxillofacial Surgery, 5Swedish Neuroscience Institute, Swedish Medical Center, Seattle, WA 98122, USA Correspondence to: Joe Iwanaga. Seattle Science Foundation, 550 17th Ave, James Tower, Suite 600, Seattle, WA 98122, USA. Email: [email protected]. Abstract: The auriculotemporal nerve (ATN) is a branch of the mandibular nerve and has been implicated for some migraines and its role in Frey’s syndrome is well known. An adult cadaver was found to have a duplicated ATN. The anterior trunk ascended as the superficial temporal artery and gave off the branches to the temporomandibular joint, parotid gland, external acoustic meatus and temporal region and communicated with a posterior trunk of the ATN. The posterior trunk ascended via the subcutaneous tissues 1 mm anterior to the auricle and gave off the branches to the anterior auricular region, temporal region and communicated with the anterior trunk. Such a duplicated ATN might be injured with preauricular skin incisions. Knowledge of such an anatomical variation might assist surgeons in iatrogenic injury of the ATN. Keywords: Auriculotemporal nerve (ATN); infratemporal fossa; Frey’s syndrome; mandibular nerve Submitted Aug 09, 2016. Accepted for publication Aug 17, 2016. doi: 10.21037/gs.2016.09.02 View this article at: http://dx.doi.org/10.21037/gs.2016.09.02 Introduction Case presentation The auriculotemporal nerve (ATN) is one of the branches During the dissection of a cadaver that was 87-year-old at of the mandibular division (V3) of the trigeminal nerve.
    [Show full text]
  • Oculoplastics/Orbit 2017-2019
    Academy MOC Essentials® Practicing Ophthalmologists Curriculum 2017–2019 Oculoplastics and Orbit *** Oculoplastics/Orbit 2 © AAO 2017-2019 Practicing Ophthalmologists Curriculum Disclaimer and Limitation of Liability As a service to its members and American Board of Ophthalmology (ABO) diplomates, the American Academy of Ophthalmology has developed the Practicing Ophthalmologists Curriculum (POC) as a tool for members to prepare for the Maintenance of Certification (MOC) -related examinations. The Academy provides this material for educational purposes only. The POC should not be deemed inclusive of all proper methods of care or exclusive of other methods of care reasonably directed at obtaining the best results. The physician must make the ultimate judgment about the propriety of the care of a particular patient in light of all the circumstances presented by that patient. The Academy specifically disclaims any and all liability for injury or other damages of any kind, from negligence or otherwise, for any and all claims that may arise out of the use of any information contained herein. References to certain drugs, instruments, and other products in the POC are made for illustrative purposes only and are not intended to constitute an endorsement of such. Such material may include information on applications that are not considered community standard, that reflect indications not included in approved FDA labeling, or that are approved for use only in restricted research settings. The FDA has stated that it is the responsibility of the physician to determine the FDA status of each drug or device he or she wishes to use, and to use them with appropriate patient consent in compliance with applicable law.
    [Show full text]
  • PERFORATION of INFERIOR ALVEOLAR NERVE by MAXILLARY ARTERY Prakash Billakanti Babu, Ramachandra Bhat K, Vanishree S Nayak
    Inferior alveolar nerve Rev Arg de Anat Clin; 2011, 3 (3): 124-129 __________________________________________________________________________________________ Case report PERFORATION OF INFERIOR ALVEOLAR NERVE BY MAXILLARY ARTERY Prakash Billakanti Babu, Ramachandra Bhat K, Vanishree S Nayak Kasturba Medical College, Manipal University, Manipal, Karnataka, India RESUMEN La fosa infratemporal es un área anatómica inferior alveolar nerve originated from the clínicamente importante para la administración de mandibular nerve by two roots and the first part agentes anestésicos locales en odontología y cirugía of the maxillary artery was incorporated between maxilofacial. Fueron estudiadas variaciones en la them. An embryologic origin of this variation and anatomía del nervio alveolar inferior y la arteria maxilar its clinical implications is discussed. Because the en la disección infratemporal. Durante la disección rutinaria de la cabeza en el cadáver de un varón maxillary artery runs between the two roots of the adulto, fue observada una variación excepcional en el inferior alveolar nerve, and the nerve was fixed origen del nervio alveolar inferior y su relación con las between the foramen ovale and mandibular estructuras circundantes. El nervio alveolar inferior se foramen, neurovascular entrapment may cause originaba en el nervio mandibular por dos raíces y la pain numbness or headache and may interfere primera parte de la arteria maxilar estaba incorporada with the injection of local anesthetics into the entre ambas. El origen embriológico de esta variación infratemporal fossa. Anatomical variations in this y sus implicaciones clínicas es debatido. Dado que la region should be kept in mind, particularly in arteria maxilar transcurría entre las dos raíces del cases of failed treatment of trigeminal neuralgia.
    [Show full text]
  • (Ear) Surgery Under Local Anaesthesia
    OPEN ACCESS ATLAS OF OTOLARYNGOLOGY, HEAD & NECK OPERATIVE SURGERY LOCAL AND REGIONAL ANAESTHESIA TECHNIQUES FOR OTOLOGIC (EAR) SURGERY Alexander Bien, Richard Wagner, Eric Wilkinson The logistics of performing otologic (ear) ing devices would still be needed. Again, surgery in developing countries and in this returns to the issue of safety. humanitarian settings are challenging. Im- plementing the use of local anaesthesia to Another reason is that of recovery time and perform middle ear and mastoid surgery in turnover; the ability to perform more cases such situations has many advantages. in a shorter amount of time. Time is of the essence in the humanitarian setting, even This article will outline the rationale for more so than in a Western medical setting. local anaesthesia in otologic surgery as well A humanitarian mission may be limited to a as educate the reader about local anesthetic certain number of days or even daylight agents and the anatomy of the ear that hours. The capacity to perform even one allows local anaesthesia to be an effective additional case in any given day may trans- means under which to perform otologic late into the benefit of many - depending on procedures. the duration of the outreach - more patients. No time needs to be allotted for the reversal Rationale for Local Anaesthesia of anaesthesia and the monitoring needs during recovery are minimal - limited Performing otologic procedures under local primarily to observation. Most, if not all, of anaesthesia - as opposed to general anaes- these concerns are eliminated with the use thesia - has many advantages in a humani- of purely local anaesthetic.
    [Show full text]