BPPVn

BPPVn, or benign paroxysmal positional vertigo - nonclassic variant, is a term used in some clinical discussions to describe atypical presentations of BPPV. Unlike classic canalithiasis or cupulolithiasis, BPPVn denotes cases with nystagmus patterns, canal involvement, or latency that do not fit conventional categories. The term is not universally standardized.

BPPVn shares the basic pathophysiology of BPPV, with otoconia dislodged into the semicircular canals, most often the posterior canal. In BPPVn, debris may produce nonclassic canalithiasis, cupulolithiasis with atypical nystagmus, multiple canals, or mixed mechanisms, causing variable findings.

Clinical features include brief vertigo triggered by head movement, but latency and nystagmus direction may be nonclassical. Some patients have little latency, variable duration, or limited response to standard maneuvers. Red flag symptoms should prompt evaluation for central pathology.

Diagnosis relies on history and positional tests, notably the Dix-Hallpike and the supine roll test. In BPPVn, eye movements may be atypical, and video-oculography or tailored maneuvers can aid assessment.

Treatment follows BPPV care, with canalith repositioning maneuvers (eg, Epley) and vestibular rehabilitation, adapted to canal involvement and response. Repeated sessions may be needed.

Prognosis is generally favorable; most respond to repositioning, though recurrence is common.

See also: Benign paroxysmal positional vertigo, canalithiasis, cupulolithiasis.