4. Complete the following statements about evoked potentials:

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a. Evoked potentials offer limited usefulness because they are _____.

delayed (and therefore less valuable in alerting surgeon to intraoperative injury)

b. Criteria for significance

     i. increased latency of _____%

10%

     ii. decreased amplitude of _____%

50%

5. Intraoperative SSEP may localize the primary sensory cortex by_____ _____ potential across the central sulcus.

phase reversal

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6. Evoked potentials during spine surgery

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a. may remain unchanged by injury to the _____ cord

anterior

b. but are sensitive to injury to the _____ columns of the _____ cord

posterior, dorsal

7. True or False. Regarding transcranial (i.e., motor evoked) potentials:

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a. Too painful to do on the awake patient

true

b. Feedback is prompt, almost immediate

true

c. Can’t record continuously because of muscle contractions

true

d. Useful for cervical spine surgery

true

e. Useful for thoracic spine surgery

true

f. Useful for lumbar spine surgery

false

g. Have more special anesthetic requirements

true

8. Provide the SSEP deterioration plan.

Hint: r³s³tahe

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r_____

remove hardware

b. r_____

reposition patient

c. r_____

release traction

d. s_____

sixty Hz

e. s_____

steroids

f. s_____

stop surgery

g. t_____

temperature

h. a_____

anemia

i. h_____

hypotension

j. e_____

electrode contact

9. Name the location of the generators for the brain stem auditory evoked potentials (BSAER) test.

Hint: diplomu (Fig. 10.1)

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Fig. 10.1 (Reprinted with permission from Greenberg MS. Handbook of Neurosurgery, 6th ed. New York: Thieme; 2006:146. Copyright © 2006 Mark S. Greenberg. All rights reserved.)

a. p¹ d _____e_____ n_____

distal eighth nerve

b. p² p_____ e_____ or c_____

proximal eighth or cochlear nucleus

c. p³ l_____ p_____ /s_____ o_____ c_____

lower pons/superior olivary complex

d. p⁴ m_____ -u_____ p_____

mid-upper pons

e. p⁵ u_____ p_____ or i_____ c_____

upper pons or inferior colliculus

f. d¹ _____ e_____ n_____

distal eighth nerve

g. p_____ e_____ n_____

proximal eighth nerve

h. lo_____

lower

i. m_____

middle

j. u_____ p_____

upper pons

10. Name the parts of the EMG examination.

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a. i_____ a_____

insertional activity

b. s_____ a_____

spontaneous activity

c. v_____ a_____

volitional activity

11. How long following denervation of muscle after nerve injury do you start to see fibrillation potentials on electromyography (EMG)?

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a. The earliest is _____, but

10 days

b. reliably not until_____,

3 to 4 weeks

c. Therefore don’t order EMG until at least _____ weeks after injury.

4

12. SNAP

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a. aka _____ _____ action potential ganglion

sensory nerve

b. lies within the _____ _____

neural foramen

c. Herniated disc is preganglion; therefore, SNAP is _____ _____.

not affected

13. H reflex

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a. is practical only regarding the_____ root.

51

b. has similar information to the _____ _____.

ankle jerk

14. True or False. Regarding EMG:

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a. Is low yield for radiculopathy

true

b. Best reserved for patients with weakness

true

c. Pain without weakness, EMG has low yield

true

15. True or False. Radiculopathy EMG is

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a. Reliable if negative

false—EMG is not sensitive for radiculopathy

b. Reliable if positive

true—When positive it is very specific

16. True or False. Paraspinal mm testing is useful for lumbar disc disease.

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a. Preop

true

b. Postop

false—muscles cut during surgery