MENINGES AND VENOUS SINUSES NEW

Views:
 
Category: Entertainment
     
 

Presentation Description

No description available.

Comments

Presentation Transcript

MENINGES AND VENOUS SINUSES:

MENINGES AND VENOUS SINUSES

MENINGES:

MENINGES COVERINGS OF BRAIN THREE - FROM OUTSIDE TO INSIDE DURA MATER ARACHNOID MATER PIA MATER

DURA MATER:

DURA MATER Outermost, thickest and toughest covering Two layers Outer- Endosteal layer Inner – Meningeal layer FUSED WITH EACH OTHER EXCEPT WHERE THEY FORM FOLDS ENCLOSING CRANIAL VENOUS SINUSES BETWEEN THEM

ENDOSTEUM/ENDOCRANIUM:

ENDOSTEUM/ENDOCRANIUM Continuous with periosteum lining outside of skull With periosteal lining of orbit through SOF Provides sheaths for cranial nerves which fuse with epineurium Forms sheath over optic nerve which becomes continuous with sclera Outer surface adherent to inner surface of cranial bones by fibrous & vascular processes

MENINGEAL LAYER:

MENINGEAL LAYER Fused with endosteum all over , except where it forms folds which project inwards dividing cranial cavity into various compartments. Continuous with spinal duramater

FOLDS OF DURAMATER:

FOLDS OF DURAMATER Four folds are Falx Cerebri Tentorium Cerebelli Falx Cerebelli Diaphragma Sellae

FALX CEREBRI:

FALX CEREBRI Large sickle shaped Two ends Two margins Two surfaces

PowerPoint Presentation:

Falx cerebri Superior sagittal sinus Inferior sagittal sinus Straight sinus * Frontal crest Crista galli RELATIONS

TENTORIUM CEREBELLI:

TENTORIUM CEREBELLI Tent shaped Supratentorial / Infratentorial Two margins Two surfaces

PowerPoint Presentation:

TENTORIUM CEREBELLI Relations Trigeminal or Meckel’s cave Triangular area

FALX CEREBELLI:

FALX CEREBELLI Small sickle shaped Base Apex Two margins Relations

DIAPHRAGMA SELLAE:

DIAPHRAGMA SELLAE Small circular, horizontal Attachments

BLOOD SUPPLY:

BLOOD SUPPLY

NERVE SUPPLY:

NERVE SUPPLY Divisions of trigeminal nerve Anterior cranial fossa - A nterior & Posterior ethmoid nerves, branches of ophthalmic div Middle cranial fossa - M axillary div of trigeminal and nervous spinosus - meningeal br mandibular nerve Posterior cranial fossa - C1,C2, C3 nerves and IX & X cranial nerves

APPLIED ANATOMY:

APPLIED ANATOMY Pain sensitive intracranial structures Headache Extra dural and Subdural haemorrhage

DURAL VENOUS SINUSES :

DURAL VENOUS SINUSES Blood-filled spaces situated bet layers of Dura mater. Lined by endothelium. Walls are thick, composed of fibrous tissue. Have no muscular tissue. Have no valves . Tributaries Brain Diploic veins of skull Orbit Internal ear

DURAL VENOUS SINUSES:

DURAL VENOUS SINUSES PAIRED Cavernous sinus Sphenoparietal sinus Sup petrosal sinus Inf petrosal sinus Transverse sinus Sigmoid sinus Petrosquamous sinus Middle meningeal sinus

DURAL VENOUS SINUSES:

Sup sagittal sinus Inferior sagittal sinus Straight sinus Occipital sinus Ant intercavernous Post intercavernous Basilar plexus of veins UNPAIRED DURAL VENOUS SINUSES

CONFLUENCE OF SINUSES:

CONFLUENCE OF SINUSES

PowerPoint Presentation:

Site Size Anterior end Posterior end CAVERNOUS SINUS

CAVERNOUS SINUS:

CAVERNOUS SINUS Structures in lat wall Floor Roof Medial wal Lateral wall Structures passing through RELATIONS

TRIBUTARIES & COMMUNICATIONS:

TRIBUTARIES & COMMUNICATIONS

TRIBUTARIES & COMMUNICATIONS:

Facial vein via Sup. Ophthalmic vein & Angular vein Or Via pterygoid venous plexus & deep facial vein Pterygoid venous plexus through emissary veins through foramen ovale , lacerum &emissary sphenoidal foramen Superior Sagittal Sinus via Superficial Middle Cerebral vein & Superior anastomotic vein TRIBUTARIES & COMMUNICATIONS

APPLIED ANATOMY:

APPLIED ANATOMY CAVERNOUS SINUS THROMBOSIS CAUSES : Sepsis in dangerous area of face , paranasal sinuses, nasal cavities SYMPTOMS: Severe pain in eye & forehead Internal ophthalmoplegia Edema of eye lids, cornea, nose, Exophthalmos PULSATING EXOPHTHALMOS

ARACHNOID MATER:

ARACHNOID MATER Second layer Intervenes between pia & dura mater Thin, transparent memb , loosely surrounds brain without dipping into sulci Bridges all irregularities of brain Except

RELATIONS :

Sub dural space Traversed by cerebral veins on their way to terminate into dural sinuses Sub arachnoid space RELATIONS

PROCESSES OF ARACHNOID :

Provide sheaths for cranial nerves Arachnoid villi Arachnoid granulations PROCESSES OF ARACHNOID

PIA MATER:

PIA MATER Innermost covering Thin, vascular membrane Dips into sulci & all irregularities of brain Epi pia 2. Pia-glia /Pia intima Connected by strands of pial cells No sub pial space

PROCESSES OF PIA:

PROCESSES OF PIA Sheath for cranial nerves Perivascular sheaths for vessels entering or leaving the brain Telachoroidea of 3rd & 4th ventricles

SUBARACHNOID CISTERNS:

SUBARACHNOID CISTERNS Cerebellomedullary cistern or Cisterna magna Cisterna pontis : Basilar artery Interpeduncular cistern: Circle of willis Cistern of Lateral Sulcus : Middle Cerebral Artery Cistern of great cerebral vein (Cisterna ambiens ): pineal gland , great cerebral vein Lumbar cistern: lumbar puncture

PowerPoint Presentation:

Median sagittal section to show the subarachnoid cisterns & circulation of CSF Superior cistern Interpeduncular cistern Cerebellomedullary cistern Chiasmatic cistern Pontine cistern

CEREBROSPINAL FLUID:

CSF : clear, colorless fluid Acts as a transport medium for nutrients & waste products & provides a protective fluid cushion for the CNS Production : Choroid plexuses of the lateral, third and fourth ventricles CEREBROSPINAL FLUID

PowerPoint Presentation:

Blood- CSF barrier CSF- Brain barrier CIRCULATION

FUNCTIONS OF CSF :

FUNCTIONS OF CSF Cushion & shock absorber Provides mechanical buoyancy & support for the brain Nourishes the CNS Removes metabolites from the CNS Serves as a pathway for pineal secretions to reach the pituitary gland

CLINICAL APPLICATION:

CLINICAL APPLICATION Froin ’s Syndrome Queckenstedt’s test Hydrocephalus "hydro“ -water " cephalus “- head. Types Non communicating Communicating

authorStream Live Help