BASE OF CRANIUM FROM EXTERNAL SIDE HARD PALATE

BASE OF CRANIUM FROM EXTERNAL SIDE HARD PALATE OCCIPITAL CONDYLE FORAMEN MAGNUM C)HARD PALATEHORIZONTAL PLATE OF PALATINE BONES & PALATINE PROCESS OF MAXILLARY BONES B)OCCIPITAL BONEHAS FORAMEN MAGNUM- SPINAL CORD; OCCIPITALCONDYLESFOR C 1 -ATLAS

INCISIVE FORAMEN GREATER PALATINE FORAMEN LESSER PALATINE FORAMEN

4. BASE OF SKULL - COMPLEX C)HARD PALATEPALATINE BONES & PALATINE PROCESS OF MAXILLARY BONES STYLOID PROCESS OCCIPITAL CONDYLE FORAMEN MAGNUM A) TEMPORAL BONEHAS STYLOID PROCESS - MUSCLE ATTACH B) OCCIPITAL BONEHAS FORAMEN MAGNUM- SPINAL CORD; OCCIPITAL CONDYLES- FOR C 1 ATLAS

1. SPHENOID BONE – ‘CORE’ OF SKULL 2)SPINE OF SPHENOID INFERIOR SIDE ATTACH LIGAMENT LATERAL & MEDIAL PTERYGOID PLATES MUSCLE ATTACH

HAMULUS OF MEDIAL PTERYGOID PLATE MEDIAL AND LATERAL PTERYGOID PLATES EXTERNAL AUDITORY MEATUS

CT Horizontal Pterygoid Plate Part 1

SPHENOID BONE-INSIDE SKULL forms parts of all cranial fossae; has: LESSER WING OF SPHENOID GREATER WING SELLA TURCICA i) Lesser Wing above superior orbital fissure; ii) Greater Wingbelow superior orbital fissure extends laterally; iii) Sella Turcica(turkish saddle) depression above main part (body)

GREATER WING OF SPHENOIDLATERAL SIDE OF SKULL

FORAMEN OVALE FORAMEN SPINOSUM

SPINE OF SPHENOID BONE – Ligament attach

BONY PART OF AUDITORY TUBE EXTERNAL AUDITORY MEATUS

TYMPANIC MEMBRANE MIDDLE EAR PHARYNX EXTERNAL AUDITORY MEATUS AUDITORY TUBE (EUSTACHIAN TUBE)

CAROTID CANAL – OPENS TO FORAMEN LACERUM INSIDE MIDDLE CRANIAL FOSSA

OPENING OF CAROTID CANAL (FORAMEN LACERUM) – INTERNAL CAROTID ARTERY, SYMPATHETIC PLEXUS

STYLOID PROCESS MASTOID PROCESS

STYLOMASTOID FORAMEN – VII

VII - FACIAL leaves Post. Cranial fossa via Internal Aud. Meatus - enters facial canal 1. Greater Petrosal N. GVE parasymp to Lacrimal gland, mucous glands of nose and palate, sens. to Nasopharynx 2. Stapedial N. - SVE motor to stapedius VII 3. Chorda Tympani SVA taste to ant 2/3 tongue GVE parasymp to submandibular, subling. salivary glands

MIDDLE EAR: BOUNDARIES brain MEDIAL WALL OF TYMPANIC CAVITY = LATERAL WALL OF INNER EAR Oval window Facial nerve canal 5. Medial Wall Promontory - cochlea Round window NOSE Oval window (fenestra vestibuli) = attach stapes; Round window (fenestra cochlea) other end of cochlea

VII - FACIAL 4. Posterior Auricular nerve Sensory to outer ear Motor auricular muscles occipitalis, frontalis 5. Motor Branches to Stylohyoid & Post Belly Digastric Post Auricular Stylohyoid & Post Belly Digastric 6. Motor to muscles of facial expression: Temporal, zygomatic, buccal, mandibular, cervical

JUGULAR FORAMEN

HYPOGLOSSAL CANAL - LOOK UNDER OCCIPITAL CONDYLE

NASAL CAVITY SPHENOPALATINE FORAMEN

PETROTYMPANIC` FISSURE

PTERYGOMAXILLARY FISSURE – LEADS TO PTERYGOPALATINE FOSSA

POSTERIOR SUPERIOR ALVEOLAR FORAMINA – IN MAXILLARY BONE – CONNECT INFRATEMP. FOSSA TO MAX TEETH POST. SUP. ALV. N. , A. , V.

FORAMEN OVALE FORAMEN SPINOSUM PTERYGOMAXILLARY FISSURE – LEADS TO PTERYGOPALATINE FOSSA

FORAMEN OVALE NOSE FORAMEN SPINOSUM MIDDLE MENINGEAL A. INFERIOR ALVEOLAR N. (V 3) POSTERIOR SUPERIOR ALVEOLAR N. V 2 LINGUAL N. V 3

FORAMINA OF ORBIT FORAMINA- MOST THINGS ENTER ORBIT FROM MIDDLE CRANIAL FOSSA 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, V 1, VI, OPTHALMIC VEINS

OPTIC FORAMEN CN II OPTIC NERVE, OPHTHALMIC ARTERY

FORAMINA OF ORBIT: OPTIC FORAMEN AND CANAL

SUPERIOR ORBITAL FISSURE – CN III, IV V 1, VI, OPHTHALMIC VEINS

SUPERIOR ORBITAL FISSURE INFERIOR ORBITAL FISSURE

2) SUPERIOR ORBITAL FISSURE BETWEEN GREATER AND LESSER WINGS OF SPHENOID, CONTAINS III, IV, V 1, VI, OPTHALMIC VEINS 1) OPTIC CANAL- IN BASE OF LESSER WING OF SPHENOID BONE, CONTAINS OPTIC NERVE & OPHTHALMIC ARTERY 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. (V 2, 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 FORAMINABETWEEN ETHMOID & FRONTAL BONES CONNECT ORBIT & NASAL CAVITIES CONTAIN ANT & POST ETHMOIDAL N. , A. & V. (V 1 & OPHTHALIC A. )

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- 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 V 1, OPTHALMIC A. and V. 2) INFRAORBITAL FORAMEN- IN MAXILLARY BONE CONTAINS INFRAORBITAL N. , A. and V. FROM V 2 & MAXILLARY

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

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

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

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

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