Are the three canals equally susceptible to benign paroxysmal positional vertigo?

A prospective study of patients diagnosed with 'single-canal' benign paroxysmal positional vertigo (BPPV) was performed. Demographic, etiological and prognostic differences between patients with posterior, horizontal and superior canal BPPV were studied. A total of 614 patients diagnosed in a period of 11 years and with a follow-up period of at least 1 year were included in the study. The posterior semicircular canal was affected in 543 casas (88.4%), the horizontal in 39 (6.4%) and the superior canal in 32 (5.2%). Final status at the end of the follow-up period was better in posterior canal BPPV (95% cure) than in horizontal or superior canal BPPV (87% cure in both cases). This may be explained by two facts: a poorer initial response to repositioning maneuvers in anterior canal BPPV than in BPPV involving the other two canals, and a poorer response to maneuvers in recurrences of horizontal canal BPPV.