Pretest_12_Neurosurgery

Question 1

In the Glasgow Coma Score, why is “T” used?

Answer 1

to indicate intubation

Question 2

A score of ______ on the GCS is indicative of severe TBI

Answer 2

8 or less (minimal is 3)

Question 3

What does the GCS assess?

Answer 3

eye opening (4), verbal response (5), motor response (6)

Question 4

How do you calculate the cerebral perfusion pressure? What should the CPP be?

Answer 4

MAP - ICP. CPP should be greater than 70

Question 5

What is a normal ICP?

Answer 5

5-15; need to keep it less than 20

Question 6

Why is hyperventilation not a good idea to decrease ICP in the long run?

Answer 6

It decreases cerebral perfusion (2/2 to vasoconstriction) to an already ischemic brain

Question 7

CT and MRI revealing an irregular brain lesion with hypodense central necrosis, peripheral ring enhancement of highly cellular tumor tissue, and surrounding edema nad mass effect:

Answer 7

glioblastoma multiforme (the most common primary intracranial neuroepithelial tumor)

Question 8

From what are glial cell tumors derived?

Answer 8

malignant degeneration of an astrocytoma or anaplastic astrocytoma

Question 9

Ring enhancing brain lesion in an immunocompetent patient:

Answer 9

metastatic tumor (lung, kidney, GI, melanoma)

Question 10

T/F: All depressed skull fractures (when skull is displaced inward) should be surgically elevated.

Answer 10

True! Especially if it is deprssed more than 1 cm, if a fragment is over the motor strip, or if small sharp fragments are seen on x-ray

Question 11

What are compound skull fractures?

Answer 11

Bone and overlying skin are broken and must be cleansed and debrided; wound must be closed

Question 12

Persistent CSF from the nose or ear for more than ___ days after a skull fracture requires surgical repair of the torn dura.

Answer 12

14

Question 13

The dumbbell shape of a pituitary macroadenoma (>1cm) results from impingement on the adenoma by the

Answer 13

diaphragm of the sella turcica

Question 14

What is Cushing triad in relation to acutely increasing ICP?

Answer 14

irregular respirations, bradycardia, hypertension

Question 15

Papilledema is a finding with (acute/chronic) increases in ICP

Answer 15

chronic

Question 16

What tumors arise from perineural fibroblasts of the peripheral nervous system?

Answer 16

Schwannomas

Question 17

T/F: Schwannomas do not involve motor nerves.

Answer 17

True

Question 18

What are the most frequent sites of cerebral contusion?

Answer 18

orbital surfaces of the frontal lobe and the anterior surface of the temporal lobes

Question 19

From where do meningiomas arise?

Answer 19

The arachnoid layer of the meninges

Question 20

What are causes of infection that can lead to brain abscess?

Answer 20

paranasal sinus infection, dental caries, ear infection

Question 21

The effects of these hematomas become apparent several days after the initial injury:

Answer 21

subdural hematoma

Question 22

What is the most common area for intracerebral hemorrhage?

Answer 22

putamen

Question 23

If intracranial hemorrhage is suspected and a patient has blown eye, what should you NOT!! do?

Answer 23

Lumbar puncture! This patient is herniating. In the presence of increased intracranial pressure, LP is contraindicated.

Question 24

What is hte pathophysiology of SIADH following head trauma?

Answer 24

Rupture of the pituitary stalk and with it the blood supply to the adenohypophysis (anterior pituitary gland). SIADH lads to sodium wasting in the urine.

Question 25

Neurogenic shock occurs in traumatic injuries when spinal cord damage disrupts sympathetic outflow, allowing parasympathetic dominance to dramatically decrease BP.
Lesions or trauma above ___ (this level) cause hypotension.

Answer 25

T5!!

Question 26

Dermatomes below the knee include what nerve roots and below?

Answer 26

L3 and below

L1-L2 is groin, L2-L3 is above the knee, anteriorly and laterally

Question 27

Anterior cord syndrome causes

Answer 27

loss of pain and temperature sensation (lateral spinothalamic tracts) and paraplegia (corticospinal tract)

Question 28

Central cord syndrome causes

Answer 28

upper extremity weakness and a cape-like distribution of loss of pain and temp sensation

Question 29

Posterior cord syndrome causes

Answer 29

loss of proprioception and vibratory sense distally (dorsal columns lost; ie tabes dorsalis)

Question 30

What is the name given to the syndrome of hyperreflexia and weakness below the lesion ipsilaterally and contralateral loss of pain and temperature?

Answer 30

Brown Sequard (hemicord) syndrome
contralateral loss begins 2 levels lower

Question 31

What is the most likely diagnosis causing “tunnel vision”?

Answer 31

prolactinoma

Question 32

There is an association between ADPKD and what neural pathology?

Answer 32

Berry aneurysms (risk of SAH!)

Question 33

Subdural hematoma looks like what on CT?

Epidural looks like what?

Answer 33

Subdural = CONCAVE

Epidural = CONVEX, lens shaped

Question 34

Which artery in the circle of Willis is most commonly affected by aneurysms?

Answer 34

anterior communicating artery