Meniere disease patients sometimes report vertiginous Meniere attacks after vestibular neurectomy that spares hearing. To determine why, the authors compared postsurgical semicircular canal function in nine patients with preserved hearing with that of a control group with no preservation of hearing. The three-dimensional head impulse test revealed residual posterior canal function in all patients with vertigo attacks (eight). The control patients had no residual canal function. Thus, residual vestibular function on the ipsilesional side may cause vertiginous Meniere attacks.