Spontaneous Reversal of Geotropic Nystagmus in Horizontal Canal Benign Paroxysmal Positional Vertigo as Diagnostic and Therapeutic Challenges

Abstract

It might make diagnosis of horizontal canal (HC) benign paroxysmal positional vertigo (BPPV) more challenging to see direction-changing nystagmus without positional change following spontaneous reversal of geotropic nystagmus (GEONYS) in supine roll test (SRT). We aimed to emphasize the importance of identifying of affected side in these patients to proceed with appropriate treatment modality. SRT was used to diagnose HC-BBPV and Barbecue maneuver with/without mastoid vibrator for treatment. We present two cases of spontaneous direction-changing BPPV without changing position. SRT revealed spontaneously changing nystagmus when the head was turned to the right and left in the first case. In the second case, nystagmus was observed in the SRT, which changed direction spontaneously only when the head was on the right. We think that Case 1 had canalolithiasis on one side and cupulolithiasis on the other, and Case 2 had canalolithiasis on side only.