Prevalence of head-shaking nystagmus in patients according to their diagnostic classification in a dizziness unit.

OBJECTIVE

In a previous publication, the authors documented the prevalence and characteristics of head-shaking nystagmus (HSN) in over 1300 consecutive dizzy patients during formal electronystagmography (ENG) at the combined Otologic Function Unit (OFU) of the Toronto and Mount Sinai Hospitals. This companion study was done to prospectively analyze a subgroup of 300 patients with known clinical diagnoses belonging to the senior author (J.R.).

METHODS

The prevalence of HSN in this series of patients with a known diagnosis is prospectively compared to the presence of HSN in a series of normal controls.

RESULTS

Results indicate that HSN is seen significantly (p < .05) in those patients with peripheral vestibular dysfunction and that the more globally the peripheral vestibular disorder involves end-organ (i.e., Meniere's) or primary afferent-neuron function (i.e., vestibular neuronitis), the more likely HSN will be present.

CONCLUSION

We further comment on the usefulness of the head-shake test and its clinical relevance in the bedside examination of the dizzy patient.