The Bascule/Pendular Maneuver: A Novel Repositioning Strategy for the Apogeotropic Variant of Posterior Canal BPPV

Background: Benign paroxysmal positional vertigo (BPPV) is the most common peripheral vestibular disorder and most frequently involves the posterior semicircular canal (PSC). Atypical apogeotropic variants of PSC-BPPV may present with pure down-beating positional nystagmus, mimicking contralateral anterior semicircular canal involvement and resulting in diagnostic and therapeutic uncertainty. Objective: To assess the effectiveness of the Bascule/Pendular maneuver in managing patients with pure down-beating positional nystagmus and suspected apogeotropic PSC-BPPV. Methods: A total of 178 patients presenting with pure down-beating positional nystagmus without a torsional component were evaluated using a standardized diagnostic protocol under video-Frenzel goggle monitoring. All patients underwent the Bascule/Pendular maneuver, a modification of the classical Semont maneuver designed to mobilize otoconial debris along the vertical canal planes (Left Anterior–Right Posterior and Right Anterior–Left Posterior), regardless of precise lateralization. Conversion of nystagmus from the apogeotropic to the geotropic variant was considered the primary outcome. Results: The maneuver was well tolerated, with no procedural interruptions or complications. Immediate conversion to the geotropic variant was achieved in 86 patients (48.3%) after a single maneuver. In the remaining patients, successful conversion was obtained after additional maneuvers, most commonly following a second application on the contralateral plane. Once geotropization was achieved, all patients were successfully treated using a standard posterior canal repositioning maneuver. Conclusions: The Bascule/Pendular maneuver is a practical and effective approach for patients presenting with pure down-beating positional nystagmus and suspected apogeotropic PSC-BPPV. By facilitating conversion to the geotropic form, it allows prompt treatment with conventional repositioning maneuvers and may represent a useful first-line strategy in atypical BPPV presentations.