SKULL SESSION- bones rigidly connected by sutures to protect brain; attach, move eyes I. CALVARIUM = SKULL CAP- Consists of bones linked by sutures FRONTAL (1)

BONES OF CALVARIUM PARIETAL (2) FRONTAL (1) SPHENOID (1) OCCIPITAL (1) NOSE TEMPORAL (2)

C. LANDMARKS B. SUTURES 1. CORONAL SUTURE NOSE C. LANDMARKS B. SUTURES 1. CORONAL SUTURE 1. BREGMA - MID POINT OF CORONAL SUTURE 2. SAGITTAL SUTURE 2. LAMBDA - MID POINT OF LAMBDOIDAL SUTURE 3. LAMBDOIDAL SUTURE

D. FONTANELLES – MEMBRANES LINK BONES AT BIRTH 1. ANTERIOR FONTANELLE AT BREGMA - FONTANELLES PERMIT CRANIAL COMPRESSION AT BIRTH - CRANIAL GROWTH 3. LATERAL FONTANELLE AT PTERION 2. POSTERIOR FONTANELLE - AT LAMBDA

LANDMARKS CORONAL SUTURE 3. PTERION - JUNCTION OF TEMPORAL SPHENOID PARIETAL & FRONTAL BONES NOSE

INTRACRANIAL HEMATOMAS 1) EPIDURAL HEMATOMA – meningeal artery, rapid other: 2) SUBDURAL HEMATOMA – venous (bridging vein, sinus), slow 3) SUBARACHNOID HEMATOMA – cerebral artery (or vein) – aneurysm or tear, rapid if arterial

E. INTERNAL STRUCTURE OF CALVARIUM OUTER MIDDLE INNER 1. INNER & OUTER TABLES - HARD CORTICAL BONE MIDDLE LAYER - SOFT SPONGY BONE CALLED DIPLOE (DOUBLE IN GREEK)

2. DIPLOIC VEINS COURSE IN DIPLOE -CONNECT BOTH TO CRANIAL CAVITY & SURFACE OF SKULL - CAN TRANSMIT INFECTION FROM SCALP TO BRAIN VIA EMISSARY VEINS

PARIETAL EMISSARY FORAMINA MASTOID EMISSARY FORAMINA

II. LANDMARKS AND BONES 1. FRONT OF SKULL FRONTAL BONE (1) NASAL BONES (2) ZYGOMATIC BONE (2)-FORMS CHEEK MAXILLARY BONE (2)-ALVEOLAR PROCESS FOR UPPER TEETH MANDIBLE(1)-ALVEOLAR PROCESS FOR LOWER TEETH ORBIT EYE SOCKET NASAL APERTURE

1. FRONT OF SKULL SUPRAORBITAL FORAMEN – IN MAXILLARY BONE ZYGOMATICO-FACIAL FORAMEN – IN ZYGOMATIC BONE INFRAORBITAL FORAMEN - IN MAXILLARY BONE MENTAL FORAMEN- IN MANDIBLE BELOW SECOND PREMOLAR TOOTH

2. LATERAL VIEW OF SKULL ZYGOMATIC ARCH- 1)ZYGOMATIC BONE 2)MAXILLARY BONE- ZYGOMATIC PROCESS 3)TEMPORAL BONE- ZYGOMATIC PROCESS TEMPORAL BONE - PARTS 1)MASTOID PROCESS - hard 2)SQUAMOUS PART- flat 3)TYMPANIC PART - ANT. TO EXTERNAL AUDITORY MEATUS TEMPORO-MANDIBULAR JOINT- FROM RAMUS OF MANDIBLE 4)PETROUS PART – inside skull

4. BASE OF SKULL - COMPLEX HARD PALATE C)HARD PALATE-PALATINE BONES & PALATINE PROCESS OF MAXILLARY BONES B)OCCIPITAL BONE- HAS FORAMEN MAGNUM- SPINAL CORD; OCCIPITALCONDYLES- FOR C1-ATLAS OCCIPITAL CONDYLE FORAMEN MAGNUM

V. CRANIAL CAVITY- DIVIDED INTO DEPRESSIONS (FOSSAE) ANTERIOR CRANIAL FOSSA (ROOF OF NASAL CAVITY, ORBIT) MIDDLE CRANIAL FOSSA (ORBIT, NASAL CAVITY, FACE) POSTERIOR CRANIAL FOSSA (FACE, ORAL CAVITY, NECK)

ANTERIOR CRAN. FOSSA -FORMED: FRONTAL, ETHMOID, SPHENOID; CONTAINS: CNI (CRIBRIFORM PLATE), FRONTAL LOBES, OLFACTORY BULB MIDDLE CRAN. FOSSA -FORMED: SPHENOID, TEMPORAL, PARIETAL ; CONTAINS: CNII-VI -TEMPORAL LOBES -PITUITARY & BRAIN STEM POSTERIOR CRAN FOSSA -FORMED: SPHENOID, TEMPORAL, OCCIPITAL, PARIETAL; CONTAINS - CNVII-XII -CEREBELLUM, BRAINSTEM -FORAMEN MAGNUM TRANSMITS SPINAL CORD, VERTEBRAL ARTERIES

SKULL SESSION 1: FORAMINA OF INTERIOR OF SKULL AND CRANIAL NERVES Basic facts: 1) Cranial nerves are numbered 1-12 2) Learn foramina of interior of skull in anterior-posterior sequence; this reflects numbering of cranial nerves

CRANIAL NERVES I II III, IV, V1, VI V2 V3 Middle Meningeal A. NOSE CRANIAL NERVES ANTERIOR I II III, IV, V1, VI V2 V3 Middle Meningeal A. VII, VIII IX, X, XI XII POSTERIOR

CRANIAL NERVES  I. Olfactory II. Optic III. Oculomotor IV. Trochlear V. Trigeminal VI. Abducens VII. Facial VIII. Vestibulo‑cochlear IX. Glossopharyngeal X. Vagus XI. Accessory XII. Hypoglossal

CRISTA GALLI OF ETHMOID OLFACTORY FORAMEN – CN I OLFACTORY NERVE

OPTIC FORAMEN CN II OPTIC NERVE

SUPERIOR ORBITAL FISSURE – CN III, IV V1, VI OPHTHALMIC VEINS

CAVERNOUS SINUS SELLA TURCICA

VENOUS SINUSES 7. Cavernous sinuses - in middle cranial fossa; on side of the body of the sphenoid bone; connected by Intercavernous sinus; receive blood from Sup. and Inf. Ophthalmic veins, Cerebral veins; drain to Sup. and Inf. Petrosal sinuses 8. Sup. and Inf. Petrosal sinuses - on petrous part of temporal bone Sup. drains to Transverse Inf. Drains to Internal Jugular

FORAMEN ROTUNDUM – CN V2

FORAMEN OVALE – CN V3 FORAMEN SPINOSUM

F. BLOOD SUPPLY TO CALVARIUM 1) OUTER SURFACE – ARTERIES TO SCALP 2) INNER SURFACE- MENINGEAL ARTERIES COURSE NEXT TO BONE; MISNAMED - SOUND LIKE SUPPLY MENINGES- MOST BLOOD TO BONES

OPENING OF CAROTID CANAL (FORAMEN LACERUM)

BASE OF CRANIUM FROM EXTERNAL SIDE HARD PALATE C)HARD PALATE-PALATINE BONES & PALATINE PROCESS OF MAXILLARY BONES B)OCCIPITAL BONE- HAS FORAMEN MAGNUM- SPINAL CORD; OCCIPITALCONDYLES- FOR C1-ATLAS OCCIPITAL CONDYLE FORAMEN MAGNUM

MEDIAL AND LATERAL PTERYGOID PLATES EXTERNAL AUDITORY MEATUS

FORAMEN OVALE FORAMEN SPINOSUM

CAROTID CANAL – OPENS TO FORAMEN LACERUM INSIDE MIDDLE CRANIAL FOSSA

OPENING OF CAROTID CANAL (FORAMEN LACERUM)

INTERNAL CAROTID ARTERY: ENTERS SKULL PASSES THROUGH CAVERNOUS SINUS INTERNAL CAROTID ARTERY

VENOUS SINUSES 7. Cavernous sinuses - in middle cranial fossa; on side of the body of the sphenoid bone; connected by Intercavernous sinus; receive blood from Sup. and Inf. Ophthalmic veins, Cerebral veins; drain to Sup. and Inf. Petrosal sinuses 8. Sup. and Inf. Petrosal sinuses - on petrous part of temporal bone Sup. drains to Transverse Inf. Drains to Internal Jugular

DIAGRAM OF CAVERNOUS SINUS

SYMPATHETICS TO HEAD - First neuron Out T1, T2 Ascends Chain

Superior Cervical Ganglia SYMPATHETICS TO HEAD Second neuron In Joins Plexus on Internal and External Carotid Arteries 1) Unnamed branches 2) Few named branches Ex. Deep Petrosal N.

INTERNAL CAROTID ARTERY SYMPATHETIC PLEXUS ON INTERNAL CAROTID ARTERY PLEXUS ON INT. CAROTID SUP. CERVICAL GANGLION PATHWAY: - Preganglionic: OUT T1, T2 - Ascend Sympathetic Chain - synapse in Superior Cervical Ganglion - Postganglionic: Distributed with Arteries Forms Plexus on Internal and External Carotid Arteries SYMPATHETIC CHAIN OUT SPINAL CORD T1,T2

CAVERNOUS SINUS SYNDROME CAUSES 1) an aneurysm of the internal carotid artery in the cavernous sinus, 2) infection or venous thrombus (blood clot) in cavernous sinus, or by 3) pituitary tumor encroaching into sinus. NERVES EFFECTED III, IV, V1, V2, and VI and Sympathetic fibers to orbit (travel on Internal Carotid) SPREAD OF INFECTION TO CAVERNOUS SINUS

CAVERNOUS SINUS SYNDROME SYMPTOMS 1) III - Ocular palsy (impaired eye movement) - Damage III - Dilated pupil (paralyze constrictor) - No pupillary light reflex (paralyze constrictor) - No accommodation (paralyze ciliary muscle) - Ptosis (drooping eyelid, paralyze levator palpebrae superioris) 2) V1, V2 Facial pain (pressure on nerves) 3) Sympathetics on Internal Carotid Ptosis (drooping eyelid) Miosis (constricted pupil) SPREAD OF INFECTION TO CAVERNOUS SINUS

INTERNAL AUDITORY MEATUS – VII, VIII

JUGULAR FORAMEN – CN IX, X, XI

HYPOGLOSSAL CANAL – CN XII FORAMEN MAGNUM

CRANIAL NERVES  I. Olfactory II. Optic III. Oculomotor IV. Trochlear V. Trigeminal VI. Abducens VII. Facial VIII. Vestibulo‑cochlear IX. Glossopharyngeal X. Vagus XI. Accessory XII. Hypoglossal

OPTIC FORAMEN CN II OPTIC NERVE

FORAMINA OF ORBIT: OPTIC FORAMEN AND CANAL

SUPERIOR ORBITAL FISSURE – CN III, IV V1, VI, OPHTHALMIC VEINS

SUPERIOR ORBITAL FISSURE INFERIOR ORBITAL FISSURE

1) OPTIC CANAL- IN BASE OF LESSER WING OF SPHENOID BONE, CONTAINS OPTIC NERVE & OPHTHALMIC ARTERY 2) SUPERIOR ORBITAL FISSURE BETWEEN GREATER AND LESSER WINGS OF SPHENOID, CONTAINS III, IV, V1, VI, OPTHALMIC VEINS NOSE

INFERIOR ORBITAL FISSURE 1) INFERIOR ORBITAL FISSURE- SLIT BELOW SUP. ORBITAL FISSURE: BETWEEN SPHENOID & MAXILLARY - CONNECT PTERYGOPALATINE FOSSA AND INFRATEMPORAL FOSSA WITH ORBIT - CONTAINS INFRAORBITAL AND ZYGOMATIC N., A. AND V. (V2, MAXILLARY A.)

BONES OF ORBIT 3. MEDIAL WALL- INCLUDES MAXILLARY, LACRIMAL, ETHMOID, FRONTAL & SPHENOID (NASAL CAVITY IS MEDIAL TO MEDIAL WALL OF ORBIT) FRONTAL SPHENOID ETHMOID LACRIMAL MAXILLARY NOSE

ANTERIOR AND POSTERIOR ETHMOIDAL FORAMINA 2) ANT. & POST. ETHMOIDAL FORAMINA- BETWEEN ETHMOID & FRONTAL BONES -CONNECT ORBIT & NASAL CAVITIES -CONTAIN ANT & POST ETHMOIDAL N., A. & V. (V1 & OPHTHALIC A.)

NASOLACRIMAL DUCT NASOLACRIMAL DUCT OPENING OF 3) NASOLACRIMAL DUCT- IN MAXILLARY, LACRIMAL BONES & INF. NASAL CONCHA -CONTAINS MEMBRANEOUS NASOLACRIMAL DUCT & TEARS NASOLACRIMAL DUCT

OTHER FORAMINA OF ORBIT ORBIT- SERVES AS PASSAGEWAY FOR NERVES, VESSELS TO FACE, SCALP & NASAL CAVITY 1) SUPRAORBITAL NOTCH OR FORAMEN-IN FRONTAL BONE CONTAINS SUPRAORBITAL N., A. and V. FROM V1, OPTHALMIC A. and V. 2) INFRAORBITAL FORAMEN- IN MAXILLARY BONE CONTAINS INFRAORBITAL N., A. and V. FROM V2 & MAXILLARY