I. CALVARIUM = SKULL CAP- Consists of bones linked by sutures ...

PARIETAL (2)BONES OF CALVARIUMFRONTAL(1)SPHENOID (1)OCCIPITAL (1)NOSETEMPORAL (2)

CORONAL SUTURELANDMARKSNOSE3. PTERION- JUNCTION OFTEMPORALSPHENOIDPARIETAL &FRONTAL BONES

E. INTERNAL STRUCTURE OF CALVARIUMOUTERINNERMIDDLE1. INNER & OUTER TABLES - HARDCORTICAL BONEMIDDLE LAYER - SOFT SPONGY BONECALLED DIPLOE (DOUBLE IN GREEK)

2. DIPLOIC VEINSCOURSE INDIPLOE -CONNECT BOTHTO CRANIALCAVITY &SURFACE OFSKULL- CAN TRANSMIT INFECTION FROM SCALP TOBRAIN VIA EMISSARY VEINS

PARIETALEMISSARYFORAMINAMASTOIDEMISSARYFORAMINA

DURA - 2 LAYERS ARE FUSED IN MOST PLACES- Dura is tightly attachedto inner side of calvarium-Normally NoEpidural Space(unlike spinalcord)Calvariumremoved by pullingaway bone fromdura

III. VENOUS SINUSES – BETWEEN 2 LAYERSOF DURA'BRIDGING'VEINSSUBDURAL HEMATOMAEMISSARYVEINSReceive blood frombrain, orbit, emissaryveins1. Superior SagittalSinus – in upper borderof falx cerebri; ant. -foramen cecum; posttransversesinus; -communicates laterallywith venous lacunae;blood from SuperiorCerebral veins through'bridging veins'; bloodfrom emissary veins

DURAREFLECTEDBrain not removed'bridging veins'Superior Sagittal Sinus1. Superior SagittalSinus – in upper borderof falx cerebri; receivesblood from SuperiorCerebral veins through'bridging veins'Superior Cerebral veins

SUBDURAL HEMATOMA- bleed into potentialspace betweenDura & Arachnoid- from tear 'Bridging'vein or sinus- bleeding often slow- chronic subduralhematomas canremainundetected

CSF REABSORBED INTO VENOUS SINUSESArachnoid villi -sites of CSFreabsorptionSuperiorSagittalSinus

CSF REABSORBED INTO VENOUS SINUSESSubarachnoidspaceSup.SagittalSinusArachnoidVilliCSF reabsorbs into venous sinuses at ArachnoidVilli; Reduced Re-Absorption – Hydrocephalus- In elderly arachnoid villi can become calcified-Arachnoid Granulations

VENOUS SINUSESInf. Sagittal Sinus2. Inferior SagittalSinus - in lower(free) border of falxcerebri; - joinsGreat Cerebral V.form StraightSinusGreat Cerebral Vein (of Galen)StraightSinusStraight Sinus can join Superior SagittalSinus at Confluens of Sinuses or turn left3. Straight sinus -at junction of falxcerebri andtentorium

NOSESigmoidVENOUS SINUSESSigmoid4. Transverse sinuses -inlateral fixed part oftentorium; receive bloodfrom Sup. Sagittal orConfluens5. Sigmoid sinuses -Sshapedcontinuation ofTransverse; endin Jugular Foramen; formInternal Jugular Vein6. Occipital Sinuses -infalx cerebelli; drain toConfluensTransverseTransverse

VENOUS SINUSES MAKE GROOVES IN CRANIAL CAVITYSIGMOIDSINUSTRANSVERSESINUS

VENOUS SINUSES7. Cavernous sinuses -inmiddle cranial fossa; onside of the body of thesphenoid bone; connectedby Intercavernous sinus;receive blood from Sup.and Inf. Ophthalmic veins,Cerebral veins; drain toSup. and Inf. Petrosalsinuses8. Sup. and Inf. Petrosalsinuses - on petrous part oftemporal boneSup. drains to TransverseInf. Drains to Internal Jugular

VENOUS SINUSES MAKE GROOVES IN CRANIAL CAVITYCAVERNOUSSINUSSUPERIORPETROSALSINUSINFERIORPETROSALSINUS

II. LANDMARKS AND BONES1. FRONT OF SKULLFRONTAL BONE (1)NASAL BONES (2)ORBITEYESOCKETNASALAPERTUREZYGOMATIC BONE (2)-FORMS CHEEKMAXILLARY BONE (2)-ALVEOLAR PROCESSFOR UPPER TEETHMANDIBLE(1)-ALVEOLARPROCESS FOR LOWERTEETH

1. FRONT OF SKULLSUPRAORBITAL FORAMEN – INMAXILLARY BONEZYGOMATICO-FACIAL FORAMEN– IN ZYGOMATIC BONEINFRAORBITAL FORAMEN - INMAXILLARY BONEMENTAL FORAMEN- INMANDIBLE BELOW SECONDPREMOLAR TOOTH

2. LATERAL VIEW OF SKULLZYGOMATIC ARCH-1)ZYGOMATIC BONE2)MAXILLARY BONE-ZYGOMATIC PROCESS3)TEMPORAL BONE-ZYGOMATIC PROCESSTEMPORAL BONE - PARTS1)MASTOID PROCESS - hard2)SQUAMOUS PART- flat3)TYMPANIC PART - ANT. TOEXTERNAL AUDITORYMEATUS4)PETROUS PART – inside skullTEMPORO-MANDIBULAR JOINT-FROM RAMUS OF MANDIBLE

4. BASE OF SKULL - COMPLEXHARDPALATEOCCIPITALCONDYLEC)HARD PALATE-PALATINE BONES &PALATINE PROCESS OFMAXILLARY BONESB)OCCIPITAL BONE-HAS FORAMENMAGNUM- SPINALCORD;OCCIPITALCONDYLES-FOR C1-ATLASFORAMENMAGNUM

V. CRANIAL CAVITY- DIVIDED INTODEPRESSIONS (FOSSAE)ANTERIOR CRANIALFOSSA (ROOF OFNASAL CAVITY, ORBIT)MIDDLE CRANIALFOSSA (ORBIT, NASALCAVITY, FACE)POSTERIOR CRANIALFOSSA (FACE, ORALCAVITY, NECK)

ANTERIOR CRAN. FOSSA -FORMED:FRONTAL, ETHMOID, SPHENOID;CONTAINS: CNI (CRIBRIFORMPLATE), FRONTAL LOBES,OLFACTORY BULBMIDDLE CRAN. FOSSA -FORMED:SPHENOID, TEMPORAL, PARIETAL ;CONTAINS: CNII-VI -TEMPORALLOBES -PITUITARY & BRAIN STEMPOSTERIOR CRAN FOSSA -FORMED: SPHENOID, TEMPORAL,OCCIPITAL, PARIETAL;CONTAINS - CNVII-XII -CEREBELLUM, BRAINSTEM -FORAMEN MAGNUM TRANSMITSSPINAL CORD, VERTEBRALARTERIES

SPHENOID BONE-INSIDE SKULLforms parts of allcranial fossae; has:LESSER WINGOF SPHENOIDGREATER WINGSELLA TURCICAi) Lesser Wing abovesuperior orbitalfissure;ii) Greater Wingbelowsuperiororbital fissureextends laterally;iii) Sella Turcica-(turkish saddle)depression abovemain part (body)

GREATERWING OFSPHENOID-LATERALSIDE OFSKULL

ANTERIORNOSECRANIAL NERVESIIIIII, IV, V1, VIV2V3Middle Meningeal A.VII, VIIIIX, X, XIXIIPOSTERIOR

CRISTAGALLIOFETHMOIDOLFACTORYFORAMEN –CN IOLFACTORYNERVE

OPTICFORAMENCN IIOPTICNERVE,OPHTHALMICARTERY

SUPERIORORBITALFISSURE –CN III, IVV1, VI,OPHTHALMICVEINS

CAVERNOUSSINUS –III, IV, V1, V2,VI

OPENINGOFCAROTIDCANAL(FORAMENLACERUM) –INTERNALCAROTIDARTERY,SYMPATHETICPLEXUS

FORAMENROTUNDUM –CN V2

FORAMENOVALE –CN V3,ACCESSORYMENINGEALARTERYFORAMENSPINOSUM –MIDDLEMENINGEALARTERY,NERVOUSSPINOSUS

INTRACRANIALHEMATOMAS1) EPIDURALHEMATOMA – Middlemeningeal artery, rapid

INTERNALAUDITORYMEATUS –VII, VIII

JUGULARFORAMEN –CN IX, X, XI,INTERNALJUGULARVEIN

HYPOGLOSSALCANAL –CN XIIFORAMENMAGNUM –SPINALCORD,VERTEBRALARTERY

CRANIAL NERVESI. OlfactoryII. OpticIII. OculomotorIV. TrochlearV. TrigeminalVI. AbducensVII. FacialVIII. Vestibulo-cochlearIX. GlossopharyngealX. VagusXI. AccessoryXII. Hypoglossal

BASE OF CRANIUM FROM EXTERNAL SIDEHARDPALATEOCCIPITALCONDYLEC)HARD PALATE-PALATINE BONES &PALATINE PROCESS OFMAXILLARY BONESB)OCCIPITAL BONE-HAS FORAMENMAGNUM- SPINALCORD;OCCIPITALCONDYLES-FOR C1-ATLASFORAMENMAGNUM

SPHENOID BONE – ‘CORE’ OF SKULLLATERAL &MEDIALPTERYGOIDPLATES -MUSCLEATTACH

MEDIAL ANDLATERALPTERYGOIDPLATESEXTERNALAUDITORYMEATUS

FORAMENOVALEFORAMENSPINOSUM

SPINE OFSPHENOIDBONE –Ligamentattach

BONY PARTOFAUDITORYTUBEEXTERNALAUDITORYMEATUS

TYMPANICMEMBRANEMIDDLEEARPHARYNXEXTERNAL AUDITORYMEATUSAUDITORY TUBE(EUSTACHIANTUBE)

CAROTIDCANAL –OPENS TOFORAMENLACERUMINSIDEMIDDLECRANIALFOSSA

STYLOIDPROCESSMASTOIDPROCESS

STYLO-MASTOIDFORAMEN –VII

JUGULARFORAMEN

HYPO-GLOSSALCANAL- LOOKUNDEROCCIPITALCONDYLE

PTERYGO-MAXILLARYFISSURE –LEADSTOPTERYGO-PALATINEFOSSA

POSTERIORSUPERIORALVEOLARFORAMINA –IN MAXILLARYBONE –CONNECTINFRATEMP.FOSSA TOMAX TEETHPOST. SUP.ALV.N., A., V.

FORAMENOVALENOSEFORAMENSPINOSUMMIDDLEMENINGEALA.INFERIORALVEOLARN. (V3)POSTERIORSUPERIORALVEOLAR N.V2LINGUAL N.V3

FORAMENOVALEPTERYGO-MAXILLARYFISSURE –LEADSTOPTERYGO-PALATINEFOSSAFORAMENSPINOSUM

FORAMINA OF ORBITFORAMINA- MOST THINGSENTER ORBIT FROM MIDDLECRANIAL FOSSA1) OPTIC CANAL- IN BASEOF LESSER WING OFSPHENOID BONE, CONTAINSOPTIC NERVE & OPHTHALMICARTERY2) SUPERIOR ORBITALFISSURE BETWEENGREATER AND LESSER WINGSOF SPHENOID, CONTAINS III,IV, V1, VI, OPTHALMIC VEINS

OPTICFORAMENCN IIOPTICNERVE,OPHTHALMICARTERY

FORAMINA OF ORBIT: OPTIC FORAMENOPTICFORAMENAND CANAL

SUPERIORORBITALFISSURE –CN III, IVV1, VI,OPHTHALMICVEINS

SUPERIOR ORBITAL FISSURESUPERIORORBITALFISSUREINFERIORORBITALFISSURE

2) SUPERIORORBITALFISSUREBETWEENGREATERAND LESSERWINGS OFSPHENOID,CONTAINS III,IV, V1, VI,OPTHALMICVEINS1) OPTICCANAL- INBASE OFLESSERWING OFSPHENOIDBONE,CONTAINSOPTICNERVE &OPHTHALMIC ARTERYNOSE

INFERIOR ORBITAL FISSURE1) INFERIOR ORBITAL FISSURE- SLIT BELOW SUP. ORBITALFISSURE: BETWEEN SPHENOID & MAXILLARY - CONNECTPTERYGOPALATINE FOSSA AND INFRATEMPORAL FOSSA WITHORBIT - CONTAINS INFRAORBITAL AND ZYGOMATIC N., A. AND V.(V2, MAXILLARY A.)

BONES OF ORBIT3. MEDIAL WALL- INCLUDES MAXILLARY,LACRIMAL, ETHMOID, FRONTAL & SPHENOID(NASAL CAVITY IS MEDIAL TO MEDIAL WALLOF ORBIT)SPHENOIDFRONTALETHMOIDLACRIMALMAXILLARYNOSE

ANTERIOR AND POSTERIORETHMOIDAL FORAMINA2) ANT. & POST.ETHMOIDALFORAMINA-BETWEEN ETHMOID& FRONTAL BONES-CONNECT ORBIT &NASAL CAVITIES -CONTAIN ANT &POST ETHMOIDALN., A. & V. (V1 &OPHTHALIC A.)

NASOLACRIMAL DUCTOPENING OF 3)NASOLACRIMALDUCT- INMAXILLARY,LACRIMAL BONES& INF. NASALCONCHA -CONTAINSMEMBRANEOUSNASOLACRIMALDUCT & TEARSNASOLACRIMAL DUCT

OTHER FORAMINA OF ORBITORBIT- SERVES ASPASSAGEWAY FOR NERVES,VESSELS TO FACE, SCALP &NASAL CAVITY1) SUPRAORBITAL NOTCH ORFORAMEN-IN FRONTAL BONECONTAINS SUPRAORBITAL N., A.and V. FROM V1, OPTHALMIC A.and V.2) INFRAORBITAL FORAMEN- INMAXILLARY BONE CONTAINSINFRAORBITAL N., A. and V.FROM V2 & MAXILLARY3) ZYGOMATICO- FACIALFORAMEN- IN ZYGOMATIC BONE-ZYGOMATICO-ORB. N. ,V2,

FORAMINA OF ORAL CAVITYHARDPALATEOCCIPITALCONDYLEC)HARD PALATE-PALATINE BONES &PALATINE PROCESS OFMAXILLARY BONESB)OCCIPITAL BONE-HAS FORAMENMAGNUM- SPINALCORD;OCCIPITALCONDYLES-FOR C1-ATLASFORAMENMAGNUM

INCISIVEFORAMENGREATERPALATINEFORAMENLESSERPALATINEFORAMEN

NASAL CAVITYSPHENO-PALATINEFORAMEN

PETRO-TYMPANIC`FISSURE