A new roll test to diagnose posterior semicircular canal benign paroxysmal positional vertigo

Abstract

BackgroundThe Dix-Hallpike (DH) test is a gold standard for diagnosing benign paroxysmal positional vertigo (BPPV). However, lateral semicircular canal BPPV is not rare. We have been performing the new roll test that begins from the sitting position and contains a head-hanging position, in order not to overlook lateral canal BPPV. We noticed that transient vertical/torsional nystagmus sometimes occurs during the new roll test. ObjectiveTo clarify the value of the new roll test in diagnosing posterior canal BPPV and elucidate the position that elicits nystagmus. Materials and methodsThe subjects were 100 consecutive patients (79 were female, 21 were male) with posterior canal BPPV. We classified the patients into four types based on a position that induced nystagmus. ResultsThe patient's position that elicited nystagmus varied. The supine type accounted for 24 %, the lateral type accounted for 62 %, the head-hanging type accounted for 9 %, and the DH type accounted for 5 %. ConclusionThe new roll test is valuable for diagnosing posterior canalolithiasis cases. Most patients reveal vertical/torsional nystagmus in the supine or lateral position. Therefore, performing the new roll test first is efficient at the initial visit.