Role of subjective visual vertical in patients with posterior canal benign paroxysmal positional vertigo as a prognostic marker after canalith repositioning maneuver

Objective:To study the potential role of subjective visual vertical(SVV)as a prognostic marker for canalith repositioning maneuver(CRM)in patients with posterior canal benign paroxysmal positional vertigo(PC-BPPV)for the Indian population.Methods:SVV was examined in 30 patients with PC-BPPV before and after canalith repositioning maneuver and after complete resolution of PC-BPPV.Study parameters included the mean of 10 angular tilt readings and direction of deviation,which were compared before and after CRM and following complete resolution of PC-BPPV.Results:The angle of SVV tilt was greater and deviated towards the affected ear before CRM in all patients,which decreased significantly shortly after CRM and continued to decrease after complete resolution of PC-BPPV(p<0.0001).Conclusions:SVV can be used to test utricular dysfunction in PC-BPPV.The angle of tilt improves in response to CRM,which may be used as a prognostic marker in patients with PC-BPPV receiving CRM.