Neuro Diagnostic Studies

Question 1

Electroencephalography (EEG)

Answer 1

Noninvasively reads post-synaptic potentials in brain cortex

Question 2

Most common reason to order EEG

Answer 2

Classification of seizure disorder/epilepsy
Also for dementia, TBI, tumors, encphalitis, sleep disorders

Question 3

Gamma waves

Answer 3

High freq
While focusing

Question 4

Beta waves

Answer 4

Most activities while awake

Question 5

Alpha waves

Answer 5

While relaxed or sleepy

Question 6

Theta waves

Answer 6

During stage 1 and 2 (light) sleep

Question 7

Delta waves

Answer 7

During stage 3 (deep) sleep)

Question 8

Brain wave frequnecies highest to lowest

Answer 8

Gamma>delta>alpha>theta>delta

Question 9

Evoked potential

Answer 9

Measures brain respnonse to visual, auditory, and somatosensory stimuli like electricity, flashng light, brief clicks

Question 10

Why order evoked potentials

Answer 10

Find deficits along nerve pathways to subtle to show up during neuro exam or to be noticed by pt
MRI might not can pick up problem
Intraoperative monitoring
Cortical blindness, meningitis, anoxia, optic neuritis, optic atrophy, compression, CVA

Question 11

Electormyography (EMG)

Answer 11

Records muscle activity in response to proximal stimuli

Question 12

Nerve conduction study (NCS)

Answer 12

Velocity and amplitude of neuronal actions potential

Question 13

Why to order EMG or NC

Answer 13

Localize LMN disorder
Determine axonal vs demyelinating neuropathies
Exclude neuropathy mimics (radiculopathy)
Assess diseases severity

Question 14

What part of the muscle is active at rest

Answer 14

Neuromuscular junction

Question 15

Fibrilations/positive sharp waves

Answer 15

Spontaneous discharges of individual muscle fibers
Low amplitude
Short duration
Present in neurogenic denervation (nerve injury)
Present two weeks after injury

Question 16

Fasciculations

Answer 16

Large abnormal spontaneous discharges of single motor units
Slow, irregular
Normal in small muscles of foot

Question 17

What order to treat traumatic brain injury

Answer 17

Threats to life, then limb, then eyesight
Put in C collar and spine motion precautions

Question 18

Glascow coma scale scoring

Answer 18

14-15: mild brain injury
9-13: moderate brain injury
<8: severe brain injury

Question 19

Coup injury

Answer 19

Occurs at site of injury (where object hits head)

Question 20

Contrecoup injury

Answer 20

Opposite to site of impact (where brain ricochets to other side of skull after being struck

Question 21

Diffuse axonal injury

Answer 21

Shearing of axons when brain shifts/rotates in skull
Result from traumatic acceleration or rotational injuries
Freq cause of vefetative state

Question 22

Vault fracture

Answer 22

Involves one or more of frontal, parietal, squamous of temporal, sphenoid, or interparietal bone

Question 23

Linear fracture

Answer 23

Break in cranial bone resembling thin line without splintering, depression, or distortion of bone

Question 24

Stellate fracture

Answer 24

Bone fracture lines beak and radiate from point usually from site of injury

Question 25

Depressed fracture

Answer 25

When degree of depression is greater than thickness of skull

Question 26

Basilar skull fracture

Answer 26

VSF otorrhea/rhinorhrhea Bruising on mastoid process Raccoon eyes CSF leak shows halo sign (imediate neuro consult) CN VII