M. Fujimoto et al., A STUDY INTO THE PHENOMENON OF HEAD-SHAKING NYSTAGMUS - ITS PRESENCE IN A DIZZY POPULATION, Journal of otolaryngology, 22(5), 1993, pp. 376-379
In this paper we have prospectively analyzed results from approximatel
y 1,500 Patients who underwent a head-shaking test during routine elec
tronystagmography (ENG). The incidence of head-shaking nystagmus (HSN)
in a dizzy population was relatively high (31.7%) when compared to ot
her so-called abnormalities in the routine ENG test battery. Its prese
nce was also similar in both active vs. passive head-shake tests. When
present, different types of HSN were identified (monophasic (76.8%),
biphasic (22.7%) and triphasic (0.5%)). In some cases, reversals of th
e expected ''normal'' pattern occurred. A high correlation was found t
o exist between a positive head-shake test and the presence of spontan
eous nystagmus, positional nystagmus and caloric test abnormalities.