022615 CNS trauma

Question 1

cerebral edema

Answer 1

accumulation of excess fluid in intracellular or extracellular spaces of brain

Question 2

major forms of edema

Answer 2

vasogenic edema

cytotoxic edema

Question 3

vasogenic edema

Answer 3

extracellular edema

disruption of BBB, resulting in shift of fluid from intravascular to extravascular compartment

predominantly involves white matter

Question 4

most common causes of vasogenic edema

Answer 4

primary or secondary brain tumors
abscesses
contusions
intracerebral hematomas

Question 5

cytotoxic edema

Answer 5

intracellular edema

occurs secondary to cellular energy failure

results in shift of water from extracellular to intracellular compartment

more pronounced in gray matter

Question 6

most common causes of cytotoxic edema

Answer 6

ischemia/infarct
meningitis
trauma
seizures
hepatic encephalopathy

Question 7

increased intracranial pres leads to

Answer 7

decreased perfusion

herniation syndromes

Question 8

transtentorial herniation

Answer 8

uncus/medial temporal lobe is displaced through tentorial opening

Question 9

complications of transtentorial herniation

Answer 9

ipsilateral CNIII nerve compression with pupillary dilatation

compression of brainstem (opposite midbrain peduncle containing corticospinal tracts)–the indentation is called Kernohan’s notch

posterior cerebral artery compression

Duret hemorrhage (infarct to midbrain)

Question 10

what does Kernohna’s notch cause

Answer 10

weakness and Babinski sign ipsilateral to cerebral hemispheric lesion

Question 11

Duret hemorrhage

Answer 11

FATAL brainstem hemorrhage

Question 12

cerebellar tonsillar hernation is caused by

Answer 12

caused by SYMMETRIC expansion of supratentorial contents into posterior fossa or expanding mass lesion in posterior fossa

medullary comrpession results in cardiorespiratory arest

Question 13

hydrocephalus

Answer 13

enlargement of ventricles associated with increase in CSF volume

Question 14

communicating (non obstructive) hydrocephalus

Answer 14

ventricular system is patent
increased size of ventricles may be due to arachnoid villi obstruction OR overproduction of CSF from choroid plexus papilloma

Question 15

non-communicating hydrocephalus

Answer 15

OBSTRUCTION within ventricular system

causes include tumor in ventricle, congenital malformation, thick meninges at base of brain blocking flow

Question 16

open vs closed trauma

Answer 16

open-broke skull

Question 17

focal trauma usually causes

Answer 17

focal neurological deficits, epilepsy

Question 18

diffuse trauma usually causes

Answer 18

coma or vegetative state

Question 19

comminuted skull fracture

Answer 19

multiple linear fractures radiate from point of impact

Question 20

contusion

Answer 20

superficial bruises of the brain (can actually see it on gross specimen and in scans)

usually at crests of gyri

sm blood vessels, neurons, and glia are damaged

occur in orbital, temporal regions (also occipital)

result from fall or from direct blow to head

Question 21

acute contusions

Answer 21

wedge shaped
superficial hemorrhage in cortex and meninges

micro:

• perivascular accumulation of blood
• after hrs, brain edema

Question 22

old contusions

Answer 22

gyri indented, cavitated, with brown or orange discoloration

macrophages w hemosiderin, fibrillary astrocytes

Question 23

coup contusion vs contrecoup contusion

Answer 23

coup-at point of impact

Question 24

diffuse axonal injury

Answer 24

deceleration/acceleration or angular acceleration

loss of consciouness at onset WITHOUT lucid interval

unconscious or disabled until death. lesser degress may be compatible w varying severity of neurologic deficits

widespread damage to axons

Question 25

gross lesions in diffuse axonal injury

Answer 25

white matter
acute changes (clusters of petechial hemorrhages and soft hemorrhagic foci)

chronic changes:

• hydrocephalus ex vacuo (loss of surrounding brain tissue)
• gray discoloration of white matter

Question 26

what must be present to confirm diagnosis of diffused axonal injury

Answer 26

microscopic exam:
-disrupted axons-axonal transport continues and causes axonal swellings

chronology of micro findings is:

• acute: AXONAL SWELLINGS
• subacute: microglia and AXONAL SWELLINGS
• chronic:degneration of involved fiber tracts (disappear)

Question 27

epidural hematomas are associated w

Answer 27

skull fracture and middle meningeal artery tear

LUCID INTERVAL btwn trauma and clinical symptoms

SLOW ACCUMULATION b/c of adherence btwn skull and dura

Question 28

acute subdural hematoma-symptoms?

Answer 28

most often, nonlocalizing: headache, confusion

Question 29

acute subdural hematoma

Answer 29

tear of bridging veins extending from subarachnoid space to dura

Question 30

acute subdural hematoma is more common in

Answer 30

elderly people w brain atrophy

Question 31

subarachnoid space hemorrhage

Answer 31

occur from contusions, lacerations skull base fractures, escape of blood from ventricular system

Question 32

what can cause decreased absorption at arachnoid granulations

Answer 32

miningitis
hemorrhage in subarachnoid space
sinus thrombosis

Question 33

subdural can present acutely, subacutely, or chonic:true or false

Answer 33

true