Diagnosis and management of lateral semicircular canal benign paroxysmal positional vertigo.

Objective: Describe the diagnosis, treatment, and outcome of a group of 20 patients with lateral semicircular canal benign paroxysmal positional vertigo (LSC-BPPV).

Methods: Retrospective review of 20 patients with LSC-BPPV (10 with geotropic and 10 with apogeotropic nystagmus) presenting to a tertiary balance center. Diagnosis was confirmed with infrared nystagmography in Dix-Hallpike positioning tests and supine positional tests. Patients were treated with one or more particle repositioning maneuvers.

Results: Addition of supine positional nystagmus tests to Dix-Hallpike positioning testing improves sensitivity in the diagnosis of LSC-BPPV. Treatment outcomes in the apogeotropic LSC-BPPV group were poorer than the geotropic LSC-BPPV group.

Conclusions: Adding supine positional testing to routine vestibular diagnostic testing will increase the identification of LSC-BPPV. Apogeotropic LSC-BPPV is more challenging to treat.