JAAA CEU Program

Questions refer to Nelson et al, “Static Positional Nystagmus in the Healthy Vestibular System,” 883–895.

Learner Outcomes:

Readers of this article should be able to:

• Understand the purpose and interpretation of the static positional subtest of the videonystagmography (VNG) test battery.

• Consider application of a newly revised criteria for pathologic or “significant” static positional nystagmus.

CEU Questions:

1. The difference between “positional” and “positioning” nystagmus:

   • Positional and positioning nystagmus are the same.

   • Positioning nystagmus only occurs with the patient sitting upright.

   • Positioning nystagmus is the result of moving the body and head from one position to another; positional nystagmus is observed after a person’s head or body has been placed in a stationary position.

2. One of the reported causes of positional nystagmus:

   • Cerebellum dysfunction

   • Benign paroxysmal positional vertigo (BPPV)

   • Otosclerosis

3. Positional nystagmus is thought to have a peripheral vestibular cause under the following conditions:

   • Presence of spontaneous nystagmus, direction-changing horizontal nystagmus in several positions and an accompanying unilateral weakness toward the fast phase of the positional nystagmus

   • Direction-changing horizontal nystagmus in a single position

   • Presence of spontaneous nystagmus, direction-fixed horizontal nystagmus in several positions and an accompanying unilateral weakness toward the slow phase of the positional nystagmus

4. It is necessary to do the right lateral and/or left lateral positions under the following circumstance/s.

   • The Dix-Hallpike was not previously conducted.

   • The patient complains of neck pain during the case history.

   • The head-right or head-left positions evoke horizontal nystagmus.

5. Why was including the fixation index suggested for the new criteria (Table 3)?

   • It improves the clinician’s ability to localize the lesion as either peripheral or central.

   • BPPV evaluation is typically done with the eyes open.

   • It removes the need to calculate the fixation index during caloric testing.

6. Evidence showed that this recording length may be sufficient when performing the static positional subtest of the videonystagmography (VNG) test battery:

   • 10–15 seconds

   • 50–60 seconds

   • 20–30 seconds

7. The criteria in Table 3 suggests that vertical nystagmus should be considered pathological when:

   • It is seen, even if only in one position.

   • It is seen in more than one position or if it is >2^o/sec in one position.

   • Only if it is greater >5^o/sec in a single position.

8. The proposed criteria (Table 3) did not consider this position for the static positional subtest of the VNG test battery:

   • Seated upright

   • Head-hanging right

   • Pre-caloric position

9. A finding of pathological positional nystagmus should be given under the following condition.

   • Persistent horizontal positional nystagmus in two positions

   • Persistent horizontal positional nystagmus in one position and intermittent horizontal positional nystagmus in one position

   • Persistent horizontal positional nystagmus in one position and intermittent horizontal positional nystagmus in three positions

10. Direction-changing nystagmus in a single position usually indicates:

    • A central vestibular lesion

    • Superior canal dehiscence

    • A horizontal semicircular canal lesion