Neuro Exam and Diagnostic Tests

Question 1

Why is a romberg test important for a pt with hx of syphilis

Answer 1

checks for deficits related to Tabes dorsalis (neurosyphilis) - damage to dorsal columns

Question 2

Intention tremor is result to damage in what area of CNS

Answer 2

cerebellum or spinocerebellar tracts

Question 3

resting tremor is result of damage to what area of CNS

Answer 3

substantia nigra

Question 4

Damage to the thalamus is more likely to produce what symptoms versus ddamage to the internal capsule

Answer 4

thalamus - sensory disturbance

internal capsule - weakness

Question 5

What are the therapeutic levels of phenytoin and what can be seen on exam of cranial nerves when levels are elevated?

what are other symptoms due to toxic levels pf phenytoin?

Answer 5

therapeutic is 10-20 mg/dl

likely to develop laterally beating nystagmus but some get this even at therapeutic levels

other sx’s include: ataxia, dysarthria, impaired judgement, and lethargy

Question 6

what is likely general etiology of abduscens palsy?

Answer 6

injury to CN VI or increased ICP

Question 7

what are the sites of injury with sensorineural vs conduction hearing loss?

Answer 7

SN: injury to the receptor cells in the cochlea or to the cochlear division of the auditory nerve

Conduction: injury to system of membranes and ossicles that focus sound on the cocchlea

Question 8

Ocular bobbing is seen with injury where?

Answer 8

damage to pons. lacks rapid component of nystagmus.

rapid rhythmic downbeating nystagmus likely cervicomedullary junction lesion (from meningioma at foramen magnum)

Question 9

damage to what CN would produce hyperacusis (increased sensitivity to sound) in the ipsilateral ear

Answer 9

CN VII: facial innervates stapedius (dampens sound). Hyperacusis indicates damage to facial nerve near brainstem because branch to stapedius is one of the first ones to come off the facial nerve.

Question 10

blurring of the margins of the optic disc is indicative of what?

Answer 10

increased ICP

Question 11

what is the pneumonic COWS used for?

Answer 11

caloric stimulation: with warm water you will get nystagmus with fast beat toward same ear (warm same) and with cold water you will get nystagmus fast beat to opposite ear

Question 12

Painful horner syndrome acutely after vigorous activity is virtually diagnostic of…?

Answer 12

carotid artery dissection

more frequent in people with migraines.

Question 13

what will appear most dense on CT out of the following: White matter, gray matter, pia matter, blood, or CSF

Answer 13

Blood

Question 14

what would you want to order to see an unruptured aneurysm?

Answer 14

angiography

CT is not sensitive to unruptured aneurysms unless they are more than 5 mm across

Question 15

what is most common area involved with noncommunicating hyrdocephalus

Answer 15

aqueduct of sylvius - connects 3rd and 4th ventricles

Question 16

which brain tumors are common to the posterior fossa

Answer 16

ependymoma (begins in choroid plexus), Hemangioblastoma (benign vascular tumor), Astrocytoma (probably least common to posterior fossa of these), and Medulloblastoma

Question 17

How can you tell calcification vs vascular lesion on CT

Answer 17

calcified mass is hyperdense w/o contrast, vascular lesion is hyperdense with contrast

Question 18

How should you treat a meningioma?

Answer 18

intraoperative confirmation of diagnosis and surgical resection.

Notoriously insensitive to chemo.

radiation may be considered

Question 19

chromosomes associated with NF1 vs NF2

Answer 19

NF1-17 (cutaneous)

NF2-22 (bilateral schwannomas)

Question 20

what is dysdiadochokinesia?

Answer 20

impaired ability to do rapid alternating movements

often seen in adults with MS and kids with cerebellar tumors

Question 21

what is the most prominent EEG finding in a normal individual (ie what wave at what frequency)

Answer 21

alpha wave at 8-13 Hz in relaxed adult

Question 22

describe wernicke aphasia and location of associated lesion

Answer 22

impaired naming, comprehension, and repetition with fluent speech - left frontal parietal temporal region

Question 23

what is best test to order with concern for peripheral neuropathy?

Answer 23

nerve conduction study

Question 24

After an EEG shows absence seizure (3 Hz spike and wave) what is next step in management?

Answer 24

MRI or CT of head to rule out any correctable lesions.

Question 25

what will you see on CSF of GBS pt?

Answer 25

elevated protein - otherwise normal . may be xanthochromic (yellow) due to high protein.