CNS Trauma

Question 1

Penumbra

Answer 1

Region between necrosis and normal brain tissue that is “at risk”

Question 2

Neurons that are most sensitive to ischemia and hypoglycemia

Answer 2

Large pyramidal neurons
Hippocampus- Sommer Sector
Purkinje cells of the cerebellum

Question 3

Morphology of global cerebral ischemia

Answer 3

Brain is swollen
Gyri are widened
Sulci are narrowed
Poor demarcation between gray and white matter

Question 4

Stages of global cerebral ischemia

Answer 4

Early- red neurons
Subacute- liquefactive necrosis, influx of macrophages
Repair- gliosis
Pseudolaminar necrosis- uneven destruction/preservation of cortex

Question 5

Border zone infarcts (watershed)

Answer 5

Wedge shapes
Most distant field of arterial perfusion

Between anterior and middle cerebral arteries at greatest risk

Question 6

Areas that don’t have collateral blood flow

Answer 6

Thalamus
Basal ganglia
Deep white matter

Question 7

Atherosclerosis (thrombosis)

Answer 7

Carotid bifurcation, origin of middle cerebral artery, ends of basilar artery

Often associated with HTN and DM

Question 8

Arteritis (thrombosis)

Answer 8

Infectious vasculitis (immunosuppressed and opportunistic infection)

Question 9

Origins of embolism

Answer 9

Cardiac mural thrombi
Atheromatous plaque of carotid artery
Paradoxical embolus
Surgery

Question 10

Area most often affected by embolus

Answer 10

Middle cerebral artery

Question 11

Morphology of non hemorrhagic focal cerebral ischemia

Answer 11

48hrs- pale, soft, edematous
2 to 10 days- boundary of infarct more distinct
10 d to 3 wks- liquefactive necrosis, gliosis, cavity

Question 12

Hypertensive Cerebrovascular disease: Lacunar infarcts

Answer 12

Affects deep penetrating arteries and arterioles- basal ganglia

Cause: arteriosclerosis

Occur in lenticular nucleus, thalamus, internal capsule, deep white matter

Question 13

Hypertensive Cerebrovascular disease: slit hemorrhage’s

Answer 13

Small hemorrhages that are resorbed

Question 14

Hypertensive encephalopathy Acute

Answer 14

HA, confusion, vomiting, convulsions, coma

Treat urgently to avoid increase ICP

Question 15

Hypertensive encephalopathy occurring over months

Answer 15

Multiple infarcts bilaterally in gray and white matter results in syndrome of dementia, gait abnormalities, pseudobulbar signs and neurologic deficits

Caused by multifocal vascular disease

Question 16

Multifocal vascular disease

Answer 16

Cerebral atherosclerosis
Vessel thrombosis or embolism
Cerebral arteriolosclerosis from chronic hypertension

Question 17

Binswanger disease

Answer 17

Multifocal vascular disease that predominantly involves white matter

Question 18

Intracerebral Hemorrhage

Answer 18

Peak at 60 yo

Caused by hypertension:
Accelerated atherosclerosis (large vessel)
Hyaline arteriolosclerosis (small vessel)
Weaker vessel allows aneurysms to form- commonly in basal gangli

Rupture of intraparenchymal vessel
Putamen

Question 19

Lobar hemorrhage

Answer 19

Hemorrhage into loves of cerebral hemisphere

Most common cause is cerebral amyloid angiopathy (CAA)

Question 20

Subarachnoid hemorrhage

Answer 20

Rupture of saccular aneurysm
90% in anterior circulation

Increased risk with AD polycystic kidney disease, Ehlers-Danlos, neurofibromatosis type I️, Marfan

Question 21

Morphology of saccular aneurysms

Answer 21

Thin walled outpouching
Muscular vessel wall and internal elastic laminate are not in the wall of the aneurysm
Wall of aneurysm has thickened, hyalinized intima covered by adventitia

Usually ruptures at apex

Question 22

Clinical of subarachnoid hemorrhage

Answer 22

Acutely: vasospasm from irritation of vessels by blood
Can occur in other vessels
May cause additional ischemic injury

Late sequelae:
Meningeal fibrosis and scarring
Obstruction to CSF flow and reabsorption

Question 23

Arteriovenous malformations

Answer 23

Detected at 10-30 yo
Seizure
Intracerebral hemorrhage
Subarachnoid hemorrhage

Middle cerebral artery most common site

Tangled vessels, pulsatile

Question 24

Basilar skull fracture

Answer 24

At least one of the following:

Cribiform plate
Orbital plate
Temporal bone- petrous and squamous portions
Sphenoid bone
Occipital bone

Question 25

Basilar skull fracture signs

Answer 25

Lower cranial nerve compromise

Orbital hematoma and mastoid hematoma

High risk for meningeal tear and epidural hematoma from middle meningeal artery

Question 26

Cerebral contusion

Answer 26

Rupture of small vessels

Coup: side of impact
Contrecoup: opposite side from impact

Question 27

Cerebral contusion

Answer 27

Old injuries- depressed, retracted, yellow-brown (plaque of jaune), site of epileptic focus

Question 28

Diffuse axonal injury

Answer 28

Caused by angular acceleration even without impact

Involves white matter regions

Question 29

Epidural hematoma

Answer 29

Middle meningeal artery

3rd cranial nerve- unequal pupils

Question 30

Subdural hematoma

Answer 30

Between layers of the Dura

Bridging veins- slow bleed

Question 31

Subdural hematoma morphology

Answer 31

Hematoma organizes- lysis of clot, growth of fibroblasts into hematoma, hyalinized CT

Hematoma firmly attached to Dura

Question 32

Chronic traumatic encephalopathy

Answer 32

Develops after repeated head traumas

Brain is atrophic with enlarged ventricles
Neurofibrillary tangles in superficial frontal and temporal lobe cortex

Question 33

Spinal cord injuries

Answer 33

Quadriplegia (high) may cause respiratory muscle paralysis

Paraplegia (thoracic)