Canal Conversion and Reentry of Otolith in Benign Paroxysmal Positional Vertigo

During the treatment process for benign paroxysmal positional vertigo (BPPV) using the canalith repositioning procedure, the otolith can inadvertently enter the semicircular canal instead of the utricle. Canal conversion refers to the situation where the otolith enters a different semicircular canal, while reentry occurs when the otolith returns to the same semicircular canal. The occurrence of a canal conversion can complicate the accurate diagnosis and treatment of BPPV, potentially leading to misdiagnosis and unsuccessful results in the canalith repositioning procedure. In this review, we aim to summarize the incidence, clinical features, and associated risk factors of canal conversion and reentries.