Epidural hematoma vs subdural hematoma
- appearance on CT
- mech of bleeding
Epidural:
- Lens shaped lesion on CT
- middle meningeal a bleeding from temporal bone fx
Subdural:
- Crescent shaped lesion on CT
- bridging vein bleeding
Crescent shaped bleeding on CT
-think what
Subdural hematoma
Lens shaped head bleeding on CT
-think what
Epidural hematoma
Subdural hematoma
-what population at increased risk, why
-Elderly, b/c their cortex atrophies, stretching the bridging veins in the subarachnoid space
Which type of brain herniation classically produces shifted eye gaze?
-and why?
Uncal herniation.
- pressed on CN3 oculomotor, making eye drift ‘down and out’
- also dilates eye b/c loss of PS innervation
Tonsillar herniation
-clinical presentation
-Cardiopulmonary arrest, from brainstem being pressed on
Herniation
-what causes herniation of brain
- increased intracranial pressure
- mass effect
Herniation of brain
-list 3 main, describe anatomy
- Tonsillar–tonsils into foramen magnum
- Uncal–temporal lobe uncus under the tentorium cerebelli
- Subfalcine–cingulate gyrus under the falx cerebri
Pt hits head and comes to ED. You see lens-shaped bleeding on CT but patient feels completely fine.
-concern?
-very concerned b/c epidural hematomas may take hours or even a day before neurologic symptoms occur
Epidural hematoma vs subdural hematoma
- presentation of each
- complication of each
Epidural:
-hours or even a day can precede neurologic signs
Subdural:
-progressive neurologic signs
Both: death from herniation
Uncal herniation
-presentation (3)
temporal lobe uncus under the tentorium cerebelli
- CN3 oculomotor, so eye moves “down and out” and is dilated (PS innervation)
- PCA compression–infarct of occipital lobe. (contralateral homonymous hemianopsia)
- Duret (brainstem) hemorrhage from rupture of paramedian artery
Subfalcine herniation
-presentation
-compression of ACA leads to infarct
