Electronystagmographic findings in benign paroxysmal positional vertigo.

The aim of this study was to investigate the electronystagmographic findings in patients with benign paroxysmal positional vertigo. A retrospective review of the records of 168 patients with this disease during the past 3 years was performed. Epidemiological data and results from the audiological and neuro-otologic workup, including electronystagmography, were recorded. One hundred fifty-one patients had involvement of the posterior canal, 14 of the horizontal canal, and 3 of the anterior canal. Seventy-two patients (42.8%) had abnormal findings on the caloric tests. Thirty-seven of them (22%) had canal paresis and 23 (13.7%) had directional preponderance, whereas in 12 patients (7.1%) both unilateral weakness and directional preponderance were found. Finally, 21 patients (12.5%) had spontaneous nystagmus. It may be thus concluded that electronystagmographic abnormalities are quite common in patients with benign paroxysmal positional vertigo. Their presence may be explained according to several mechanisms, which are further discussed herein.