Khanna Session 28 2022 Head & Neck PDF

BRAIN & NERVOUS SYSTEM - 13 DEEPESH KHANNA, MD, PH.D., MPH, MBA, MS, CPH LEARNING OBJECTIVES Describe the Ventricular system of the brain  Identify the structural components of the ventricular system of the brain  Define hydrocephalus and the treatment used  Name the Dural venous and cavernous si...

BRAIN & NERVOUS SYSTEM - 13 DEEPESH KHANNA, MD, PH.D., MPH, MBA, MS, CPH LEARNING OBJECTIVES Describe the Ventricular system of the brain  Identify the structural components of the ventricular system of the brain  Define hydrocephalus and the treatment used  Name the Dural venous and cavernous sinuses  DURAL VENOUS SINUSES GENERAL CONSIDERATIONS Superior sagittal sinus is shown. Channels form where the periosteal and meningeal layers of dura mater separate. Endothelium-lined channels Drain most structures of cranial cavity Sinus venous blood drains primarily into internal jugular veins. Superior sagittal sinus DURAL VENOUS SINUSES ARACHNOID GRANULATIONS Protrusions of arachnoid through the dura mater into the venous sinuses Prominent in the lateral lacunae Effect is the return of CSF to the venous circulation Arachnoid granulation DURAL VENOUS SINUSES ARACHNOID GRANULATIONS Protrusions of arachnoid through the dura mater into the venous sinuses Prominent in the lateral lacunae Effect is the return of CSF to the venous circulation Lateral lacunae DURAL VENOUS SINUSES ARACHNOID GRANULATIONS Arachnoid granulations Prominent arachnoid granulations Lateral lacunae Lateral lacunae DURAL VENOUS SINUSES TRIBUTARIES Emissary veins Arachnoid granulation Diploic veins Meningeal veins Cerebral and cerebelli veins (bridging veins) PD DURAL VENOUS SINUSES MAJOR SINUSES Superior sagittal sinus Inferior sagittal sinus Transverse sinus Cavernous sinus Sigmoid sinus Straight sinus Confluence of sinuses Superior petrosal sinus Occipital sinus CONFLUENCE OF SINUSES FORMED BY UNION OF: Superior sagittal sinus Straight sinus Confluence of sinuses Occipital sinus DURAL VENOUS SINUSES DRAINAGE Confluence of sinuses Transverses sinuses Sigmoid sinuses > bulb of internal jugular veins Bulb IJV Sigmoid sinus Confluence of sinuses Transverse sinus CAVERNOUS SINUSES RELATED STRUCTURES Internal carotid artery (ICA) Carotid plexus of sympathetic nerves (not shown) Abducent nerve (CN VI) Oculomotor nerve (CN III) Trochlear nerve (CN IV) Ophthalmic nerve (CN V/1) Maxillary nerve (CN V/2) CAVERNOUS SINUSES RELATED STRUCTURES ICA Internal carotid artery (ICA) Carotid plexus of sympathetic nerves (not shown) Abducent nerve (CN VI) Oculomotor nerve (CN III) Trochlear nerve (CN IV) Ophthalmic nerve (CN V/1) Maxillary nerve (CN V/2) CAVERNOUS SINUSES RELATED STRUCTURES ICA Internal carotid artery (ICA) - gets affected in pituitary gland tumor Carotid plexus of sympathetic nerves (not shown) Abducent nerve (CN VI) CN III CN IV CN VI Oculomotor nerve (CN III) CN V/1 Trochlear nerve (CN IV) CN V/2 Ophthalmic nerve (CN V/1) Maxillary nerve (CN V/2) Thrombophlebitis of Facial Veins Danger Triangle (Zone) CAVERNOUS SINUSES THROMBOPHLEBITIS ICA Infection from danger triangle Abducent nerve may be affected (internal strabismus). Other cranial nerves Septic thrombosis usually results in acute meningitis. CN III CN IV CN VI CN V/1 CN V/2 CAVERNOUS SINUSES PITUITARY GLAND TUMOR ICA CN III CN IV Internal carotid artery Cranial nerves CN VI CN V/1 CN V/2