A case of apogeotropic horizontal canal benign paroxysmal positional vertigo that transformed to the geotropic variant during treatment with Appiani maneuver, followed by successful treatment with Gufoni maneuver.

Lesions at three possible sites can masquerade as apogeotropic horizontal semicircular canal benign paroxysmal positional vertigo (HSC-BPPV), namely: 1) short anterior (ampullary) arm canalolithiasis; and 2) culpulolithiasis, which may be either canal (Cup-C) or utricle-sided (Cup-U). There are no clinical methods or investigations to determine the exact pathological site when a patient with a history compatible with HSC-BPPV is found to have apogeotropic positional nystagmus on the supine roll test. Therefore, the treatment of apogeotropic variant of HSC-BPPV not only poses difficulties but the therapeutic options need to be tailored according to the ostensible localization of the pathology. If the apogeotropic HSC-BPPV is transformed into the geotropic variant, it becomes relatively easier to treat, as the treatment options for the latter are very well established. There are reports of cases of the apogeotropic variant of HSC-BPPV being transformed inadvertently during diagnostic positional tests as well as during therapeutic (intention-to-treat) positional maneuvers. I report here a case of an apogeotropic variant of right HSC-BPPV, that transformed into a geotropic variant during the therapeutic (intention-to-treat) Appiani maneuver, which was subsequently successfully treated with two sequences of Gufoni maneuver after transformation. The patient was followed up at one and 24 hours after the second sequence of Gufoni maneuver with a diagnostic supine roll test, which was negative. The case report is supported by seven videos of the diagnostic and therapeutic positional maneuvers revealing positional nystagmus, its appearance, change, and disappearance as clinical events unfolded during the examination and treatment.