Can active lateral canal benign paroxysmal positional vertigo mimic a false-positive head thrust test?

Abstract

We present a patient with positive head thrust test (HTT) and video-oculography (VOG) findings suggestive of active lateral semicircular canal (LSCC) benign paroxysmal positional vertigo (BPPV). This patient was seen in a tertiary vestibular clinic for episodic vertigo. He exhibited robust corrective refixation saccades on HTT to the right and evidence of active contralateral LSCC BPPV on positional testing. Treatment of the LSCC BPPV led to immediate resolution of vertigo and near-normalization of the HTT on follow-up testing. The pathophysiologic basis and clinical implications of LSCC BPPV mimicking a false-positive HTT are discussed in detail.