Benign paroxysmal positional vertigo predominantly affects the right labyrinth.

Benign paroxysmal positional vertigo (BPPV) occurs when there are freely moving particles in a semicircular canal and the head is turned in the plane of the affected canal. The aim of the present study was to clarify whether BPPV manifests equally in both labyrinths or whether there is a preponderance for one side. We conducted a PubMed literature search of BPPV case series which specified the affected side and a retrospective chart review of 80 consecutive patients with BPPV of the posterior canal who had presented at our dizziness clinic. Eighteen studies with a total of 3426 patients were identified. In our own series the right side was affected in 54 of 80 patients (right/left ratio 2.08). Altogether, in 3506 patients the right labyrinth was involved 1.41 times more often than the left (95% CI 1.37 to 1.45). We think that the reason for the predominant involvement of the right ear in BPPV is the habit-of most patients-of sleeping on the right side.