Meninges and sinuses Flashcards
Dural venous sinus=between these two layers
meningeal+internal periostium (on bone and blends w/ meningial membrane that sticks closely together)
courses up into cranial vault
- supplies most of dura
- just deep to pterion (VERY THIN!)
Middle meningeal artery
lateral blows to head at pterion cause:
= Epidural hemitoma
CC: Epidural hematoma;
start to see dissection on meningeal layers away from bone, specifically periosteal layer (which wraps all way around cranial bone) Once hit suture line, ≠go further thus defiitive lensticular sizes)
travels on inside of skull btwn meningeal and periostal layers = extra dural~ cause a groove in bone
Middle Meningeal Artery and Vein:
Shearing of veins in subarachnoid space:
these guys don’t have specific shape = amorphous
arachnoid + space of arachnoid + pia mater, is in contact w/ CSF or space where CSF circulates
Leptomeninges:
Meninges and Superficial Cerebral Veins:
-beneath arachnoid layer; drain into?
into venous sinuses
shearing of these guys during trauma d/t fixed dura mater and mobile brain~ brain moves and these shear off and can get subarachnoid hemorrhages
Superficial cerebral veins
Tentorial Nerve does the posterior aspect of dura
V1
does the middle aspect and lateral edge of the dura
V3:
more anterior and internal part of dura
V2:Meningeal branch of Maxillary nerve
innervates most of dura
V
CC: responsible for dural headaches
V
These guys embedded w/in dura matter~
Dural Venous Sinuses:
w/in falx cerebri (double layer of dura) w/in outtermost layer→ drains into confluence of sinuses
Superior Sagittal sinus
Where does the superior sagital sinus drain into?
Confluence of sinuses
-Confluence of sinuses=
transvers (2) + Straight sinus (2)
Sinus that on either side of celica tersica
*sits close to cranial nerves
Cavernous Sinus
Cavernous Sinus drainage pattern
-blood drains from here →Superior Petrosal sinus
This sinus lies along petrossal ridge
Superior Petrosal Sinus
Drains →Internal Jugular Vein
Inferior Petrossal sinus
made of Inferior petrosal sinus + Sidgmoid Sinus as they meet
Inferior jugular vein
What passes through the Internal Jugular Foramen
IJV and CN 9, 10, 11
General flow in standing person:
Start at vortex of head→Superior Sagittal Sinus→ Confluence sinus where Transverse Sinus and Straight sinus meet up→ goes down through Transverse→Sigmoid Sinus→ becomes Internal Jugular Vein
Falx Cerebri superior edge =
superior sagittal sinus→ flows into confluence of sinuses
Falx Cerebri inferior edge=
inferior edge= inferior sagittal sinus → Straight sagittal sinus into Confluence
Orbital veins + pterigoid venous plexus contributions + deep facial vein dump into here
Cavernous sinus
Internal Jugular Vein: meets up w/ subclavian =
brachiocephalic
Which side is prefered for a Central line Cath: find SCM~ go btwn it’s 2 bellies
CC: Right side
What do these guys have in common
Facial Vein:Superior and inferior opthalmic veins
Venous plexus + Pterygoid plexus
Drain into superior sagittal sinus
Infection or thrombis in cavernous sinus is trouble bc what nerves are in this area?
CN III, IV, V1, V2, VI
Which nerve is affected first if there is infection in cavernous sinus?
VI (Abducent or lateral eye muscle so can see on eye exam and or double vision)
Symptoms of cavernous sinus infection
CC: Cavernous sinus or thrmobosis: issues w/ extraoccular eye muscle (VI and CN 3 and trochlear does one of them)
Stabbing pain along distribution of V1(tip of nose to forehead) and V2( lower eyelid to upper lip)
Infection from nasal cavities/sinus or directly from venous system
pterion made of what 4 bones
(frontal + parietal + temporal + sphenoid)
