Newly classified horizontal canal positional nystagmus and its treatment

Abstract

Objectives: Horizontal canal type BPPV shows various types of direction-changing positional nystagmus (DCPN). The aim of this study was to classify into 4 types by the duration (persistent without latency or transient with latency) and the direction (apogeotropic or geotropic) and describe the details of each type and to discuss each pathophysiological mechanism and treatment. Study design and setting: Retrospective case seriesParticipants: We conducted a retrospective case series study in 50 patients with DCPN. Positional nystagmus was examined using an infrared camera or Frenzel glasses. Main outcome measures:We compared clinical outcome parameters (frequency, affected side, sex, treatment) among the 4 types.