Bleeding in the Brain Flashcards
what can cuase an epidural hematoma
tearing of the middle meningeal artery
what is the main blood supply to the dura what is a branch of how does it enter the skull what layer does it travel in what is the external landmark
- middle meningeal artery
- maxillary artery
- formaen spinosum (middle cranial fossa)
- travel in periosteal layer
- pterion
where are the anterior meningeal branches from?
wehre are the posterior meningeal branches from?
ant: ophthalmic artery
post: from occipital and vertebral artery
what is the dura innervated mainly by
what is the supratentorial dura innvated by?
post fossa?
CN V
trigeminal nerve
vagal and upper spinal nerves
where is the middle meningeal artery located in the dura?
supratentorial dura
what is the most common cause of an epidural (extradural) hemotoma
skull fracture that results in a laceration (tear) of a major dural vessel, such as the MIDDLE MEN ARTERY
in dorsal midbrain syndrome…
- can’t look _____
- pupils dont constrict to light, but constrict to ____
- upper lids are above ______
- eyes get sucked into sockets in attempted upgaze, what is this called
- can’t look up (upgaze paralysis)
- contrict to a near target (light-near dissociatoin; “tectal pupils”
- upper lids are above sup limbus (lid retraction)
- convergence-retraction “nystagmus”
vertical gaze center is in the….
horizontal gaze center is in the..
midbrain
pons
where do projections of the INC cross
in the posterior commisure
lesions involving the projections of the INC in the PC are thought to produce…
vertical gaze abnormalities for all classes of eye movements
=particularly true for upgaze
the riMLF projections do not cross in the PC but…
bifurcate lower down
what are the levators bilaterally controlled by
the single midline central caudal nucleus (CCN) of the oculomotor nuclear complex
-in turn controlled by M-group neurons
in the downward gaze, what inhibits M-group neurons
INC
-this is what ultimately allow the lids to relax as you look down
if you have a lesion in the PC, why will yo lose the normal inhibition over the CCN and thus onto the levators
-both lids will be “retracted”
bc the INC projections cross in the PC
what does RAPD tell you
if there is optic nerve disease
