First-referral presentations of patients with benign paroxysmal positional vertigo who were negative on positional testing and who lacked nystagmus.

The aim of the present study was to explore the demographic, clinical, and pathogenetic features; and treatment outcomes of patients with benign paroxysmal positional vertigo (BPPV) who were negative upon positional testing at their first referral. A total of 133 patients presented with histories of BPPV but were negative, in our hands, upon positional testing. Patients were told to cease taking vestibular suppressant medication (if any) and were to return for re-examination when positional vertigo symptoms recurred. If BPPV was diagnosed, the appropriate repositioning maneuver was applied and patients were re-examined weekly until the characteristic nystagmus and vertigo disappeared. Follow-up was performed 1 week, 4 weeks, 3 months, 6 months, and 1 year after diagnosis. The 133 patients were compared with a group of 250 patients with typical BPPV. Sixty-five of the 133 patients (termed the n-BPPV group) were subsequently identified with typical BPPV. Such diagnoses were made within 10 days of the first referral in 37 (56.9%) cases. Patients of the n-BPPV group had a longer duration of the last episode of vertigo than did others (39.7 ± 38.4 vs. 26.1 ± 36.7 days, p < 0.001), and a higher proportion used vestibular suppressant medication prior to first referral (75.4 vs. 54.8%, p = 0.003). The n-BPPV and typical BPPV patients responded similarly to treatment and exhibited similar recurrence rates. BPPV patients who were negative upon positional testing at first referral were quite common, accounting for 26% of all typical BPPV patients. No significant difference in either treatment outcome or recurrence rate was evident between n-BPPV and typical BPPV positions. Positional vertigo and nystagmus are not always present as BPPV progresses.