The scull: principles of development and structure.
The neurocranium and splanchnocranium bones – overview.
Scull of the newborn and its growth. MUDr. Veronika Němcová, CSc. Neurocranium + splanchnocranium
E
F L P
N S T Z Max O
M Scull
neurocranium F capsula encephalica, capsula ethmoidalis, P capsula optica, capsula otica N O E T (P) V Max splanchnocranium (viscerocranium) S Pal M Scull in the newborn, in 7 years and in adult proportions
newborn
7 years neurocranium adult splanchnocranium Desmocranium and chondrocranium
• intramenbranous ossification – directly from the mesenchymal connective tissue (most of the splanchnocranium and calvaria) • enchondral ossification -ossification of the cartilaginous model (mainly bones of skull base) PRIMITIVE CHONDROCRANIUM
capsula capsula capsula occipital ethmoidea optica otica vertebrae
CARTILAGINOUS CHONDROCRANIUM AND DESMOCRANIUM
branchial arches I II VI desmocranium chondrocranium Desmocranium and chondrocranium in the newborn
os sphenoidale
os frontale os parietale
squama ossis occipitalis
os ethmoidale os occipitale os nasale
maxilla os lacrimale os temporale squama os zygomaticum
mandibula Meckels malleus cartilage desmocranium os temporale -tympanic part styloid process chondrocranium Desmocranium and chondrocranium
E
F L P
N S T Z Max O M mastoid process
styloid process pyramis Development of the scull base
Chondrocranium ethmoid bone
prechordal cartilages lesser wing
ala orbitalis greater wing hypophysial cartilage body sphenoid ala temporalis basilar part of parachordal occipital bone cartilage occipital sclerotoms periotic capsule pyramis of temporale bone occipital sclerotoms
chorda dorsalis (notochord) 6 weeks Development of the splanchnocranium – from branchial arches
1. branchial arch
incus stapes 2. branchial arch styloid process stylohyoid ligament 3. branchial arch
greater horn of the hyoid bone Meckels cartilage 4. branchial arch
6. branchial arch lesser horn of the hyoid bone epiglottis Ossification • Desmocranium Chondrocranium • os occipitale – squama • os occipitale –basis and lateral • os parietale parts • os frontale • os temporale – pyramis and • os temporale –squama mastoid process • os tympanicum • os sphemnoidale (without • os nasale medial lamina of pterygoid process) • os lacrimale • os ethmoidale • vomer • inferior nasal concha • medial lamina of pterygoid process • maleus, incus stapes • os palatinum • styloid process • os zygomaticum • hyoid bone • maxilla • mandibula (Meckel cartilage) Anterior aspect
F
N S E Z L
Max INC
V
M Openings for trigeminal nerve branches and spaces
foramen supraorbitale orbit
foramen pirifom aperture infraorbitale anterior nasal spine
foramen mentale Norma frontalis
points for measurement glabella nasion
zygion
gnathion Lateral aspect
F P
N S T L
Frankfurt plane Z O
Max
M Norma lateralis
bregma points for measurement
glabella nasion opisthocranion
zygion
gnathion Inferior aspect Teeth Maxilla
palatine bone Z infreior nasal concha S vomer T tympanic styloid bone process O P
mastoid process Inferior aspect M Z P S V T
O choana
foramen magnum Norma basalis points for measurement
opisthocranion basion Calvaria from outside
bregma sagittal suture
parietal foramen for emissary vein lambdoid suture Norma verticalis euryon points for measurement
width glabella lenght opisthocranion
euryon Calvaria from inside frontal sinus sulcus sinus sagittalis superioris
sulci arteriae meningeae mediae
granular foveolae diploe
sinus x sinus air filled cavity x vein between dura mater and periosteum or only between dura mater Skull – sagittal section - inner surface
groove - sulcus
F grooves for P middle meningeal artrery
S INC O Max grooves for sinuses M
grooves for branches of cranial nerves Skull - midline section - inner surface
F
P
N T E S O V
P Os sphenoidale
dorsum sellae lesser wing
greater wing body (cerebral orbital temporal infratemporal +sphenomaxilar surfaces)
pterygoid process posterior aspect Sphenoid bone anterior aspect - schema
„the pilot sits“ in the lesser wing hypophyseal fossa
greater wing superior orbital fissure
foramen rotundum pterygoid process sphenoid rostrum pterygoid canal
sphenoid sinus Os sphenoidale - placement
right orbit
ethmoid, frontal, occipital; parietal, temporal ethmoid, frontal, zygomatic Os sphenoidale and maxilla, palatine bone and vomer
perpendicular plate of the palatine bone vomer lateral aspect nasal septum lateral wall of the nasal cavity Os sphenoidale – inferior aspect
Os palatinum
Vomer Os sphenoidale openings and grooves aspect from superoposterior left side optic canal
sulcus prechiasmaticus fossa hypophysialis superior orbital fissure sulcus caroticus
foramen rotundum
foramen ovale canalis pterygoideus turkish saddle Sella turcica anterior clinoid process (turkish saddle)
hypohysial fossa sphenoid sinus dorsum sellae Os temporale- lateral aspect
temporale bone - squama
occipital bone
graeter wing of sphenoid zygomatic bone Os temporale inferior aspect - parts
squamous part petrosal part (pyramis)
tympanic part
styloid process mastoid process Os temporale -superior aspect
anterior and posterior wall- grooves of sinuses, nerves and squama middle meningeal artery
os petrosum – pyramis, inside are: 1) bony labyrinth 2) canalis caroticus 3) canalis nervi facialis 4) canalis musculotubarius 5) canaliculus cochlea 6) aquaeductus vestibuli 7) canaliculus tympanicus (for branch of IX.n) 8) canaliculus chordae tympani (from VII.n) 9) canaliculus mastoideus (for external branch of X.n.) Position of the inner ear in petrosal bone
cochlea
canales semicirculares (ant., post., lat.) n.vestibulocochlearis Os temporale labyrinthus osseus
1-squama 2-porus acusticus int. n.VII +VIII) 3-sulcus sinus sigmoidei 4-apex pyramidis 5-semicircular canals Os temporale cochlea
squama ossis temporalis
cochlea impressio n.trigemini antrum mastoideum Os petrosum (pyramis) - posterior wall
apertura externa aquaeductus vestibuli fossa subarcuata
Fossa cranii posterior
meatus acusticus internus (n.VII. a n.VIII.) sulcus sinus petrosi inferioris
foramen jugulare (n.IX., X., a XI.) canalis nervi hypoglossi sulcus sinus sigmoidei Os petrosum (pyramis) - posterior wall
sulcus meatus acusticus sinus internus petrosi apertura externa aquaeductus vestibuli nerves VII,VIII superioris semicircularendolymphatetic cochlea canals sac
sulcus sinus incisura jugularis petrosi inferioris sulcus sinus sigmoidei (jugular notch) nerves IX,X,XI. Fundus meatus acustici interni – nerves VII. and VIII.
area n. facialis
facial nerve –n.VII. area vestibularis superior crista transversa
A P
area vestibularis inferior cochlear nerve right pyramis posterior aspect Canalis nervi facialis
1) anterolateraly 2) posterolateraly greater 3) caudaly petrosal nerve internal acoustic meatus
facial nerve (VII.n)
cochlear nerve vestibular nerve
stylomastoid foramen Important openings on the inferior wall of petrosal bone
petrotympanic fissure (chorda tympani)
carotid canal canaliculus mastoideus internal carotid artery (ramus auricularis n.vagi) fossula petrosa (tympanic nerve) tympanomastoid fissure opening of (ramus auricularis n.vagi) canaliculus cochleae jugular fossa (internal mastoid foramen jugular vein) (emissary vein) stylomastoid foramen (facial nerve – VII.n) Middle ear cavity (cavum tympani)
Walls Sup.- tegmental wall – tegmen tympani
post. mastoid wall Med.- labyrinthic wall Lat.- membranous wall (inner ear) (drum) ant. - carotic wall
Inf.- jugular wall – jugular vein Section - anterobasal wall of petrosal bone Mastoid Epitympanic – medial wall of antrum recess the middle ear cavity
Facial canal n. stapedius
Mastoid aer cells chorda tympani
Tympanic nerve (from IX.n) Tympanic cavity – schematic frontal section Paries labyrinthicus – anterobasal wall of petrosal bone Fossa cranii media
Canalis semicircularis Recessus lateralis epitympanicus M I N. facialis
Fenestra ovalis - S vestbuli
Membrana tympani Promontorium – 1. convolution of cochlea
chorda tympani Fenestra rotunda - cochleae
Bulbus v. jugularis int. Os ethmoidale cribriform plate
orbital plate posterior aspect bulla ethmoidale air cells ethmoidalis (cellulae ethmoidales) processus uncinatus
concha nasalis media perpendicular plate Maxilla
frontal process
zygomatic process tuber maxillae
corpus maxillae (body) alveolar process Maxilla
palatine process praemaxilla (os incisivum) Maxilla
maxillary sinus Mandible lateral aspect mandibular notch condylar coronoid process process
alveolar process mental protuberance
ramus mandibulae
corpus mandibulae Mandible anterolateral view mandibular foramen
pterygoid tuberosity
masseteric tuberosity
mental foramen mandibular foramen
sublingual fossa mylohyoid line
mylohyoid groove
submandibular fossa Mandible of Karel IV.
Post traumatic changes A-C Correction of the occlusion Skull of a newborn
Lenght 11 cm Circumference 34 cm
Fonticulus anterior it closes in 2-3 years Lenght 11 cm Circumference 34 cm
fontanellae = fonticuli cranii
Fontanella major (it closes in 2. or 3.year)
Fontanella minor (it closes in 3.month) Fonticulus minor
Tuber parietale
Fonticulus major
Tuber frontaleTuber Sutura metopica Fonticulus major
Symphysis menti Angulus mandibulae Fonticulus sphenoidalis
Sutura mendosa Fonticulus angulus mandibulae Anulus tympanicus mastoideus Synchondrosis Fonticulus Synchondrosis sphenooccipitalis intraoccipitalis mastoideus anterior
Symphysis menti
Synchondrosis intraoccipitalis posterior Craniosynostoses
tuber frontale sutura metopica fonticulus anterior sutura coronalis
tuber parietale sutura sagittalis
premature closure of cranial fonticulus posterior sutures sutura lambdoidea
dolichocephaly trigonocephaly (scaphocephaly)
brachycephaly posterior plagiocephaly anterior plagiocephaly Skull of a newborn
Big neurocranium Small splanchnocranium Prominent tubera frontalia et parietalia (centers of ossification) Fonticuli cranii Possible movement among bones of the calvaria Paranasal sinuses are not fully developed Os frontale divided by a suture Suture between maxilla and premaxilla Symphysis menti Angle of mandible -150-160 degree Os tympanicum – anulus tympanicus X-ray skull of a newborn Lenticular left parietal calvarial mass-like lesion with peripheral sclerosis/calcification and central lucency. The lesion does not cross suture lines
Subperiosteal cephalohematoma. Cranial nerves !!!
• I. nn. olfactorii • II. n. opticus • III. n. oculomotorius • IV. n. trochlearis • V. n. trigeminus 1.ophthalmicus • 2.maxillaris • 3.mandibularis • VI. n. abducens • VII. n. facialis • VIII. n. vestibulocochlearis • IX. n. glossopharyngeus • X. n. vagus • XI. n. accessorius • XII. n. hypoglossus Development of the face
1- maxillary process 1 2-mandibular process 3 2 3-second branchial arch Development of the face
3 I 1
II 2 1-maxillary process 2- mandibular process 3-medial nasal process 4-lateral nasal process stadium 12 stadium 13 stadium 15
4 3
1
2 Development of the face prominentia internasal nasofrontalis groove
maxillar process oropharyngeal membrane
4 weeks 5 weeks 5,5 weeks
9 weeks 6 weeks 7 weeks Development of palate and nasal septum and nose
medial nasal process internasal groove lateral nasal process maxillar process
primary palate nasal septum palatine process Development of the palatine processes
nasal septum
tongue palatine process Meckel palatine cartilage process Sources
• Čihák, Anatomie 1 • Gray, Anatomy • Petrovický a spol., Anatomie 1 • Sobotta , Atlas anatomie člověka • Ten Donkelaar, Lohmann en Moorman, Klinische Anatomie en Embryologie • Thieme, Atlas of Anatomy • http://anat.lf1.cuni.cz/muzeum/kranio.html • Personal archiv