Sudden-onset Vertigo Associated with Persistent Spontaneous Torsional Nystagmus and Imbalance: A Unique Clinical Manifestation of Benign Paroxysmal Positional Vertigo but not Acute Unilateral Peripheral Vestibulopathy (Vestibular Neuritis)

Abstract Objective: Benign paroxysmal positional vertigo (BPPV) is the most common peripheral vestibular disease. Acute unilateral peripheral vestibulopathy (AUPVP), previously termed vestibular neuritis (VN), is the 3rd most common peripheral vestibular neuropathy with unknown etiology and pathogenesis. This study aimed to explore the association between BPPV and AUPVP(VN) and identify the potential etiology and pathogenesis of AUPVP(VN). Methods: The clinical characteristics of 11 patients with sudden-onset vertigo associated with persistent spontaneous torsional nystagmus (PSTN)and imbalance were retrospectively reviewed. The effectiveness of the CCRM treatment was evaluated. The diagnosis of these patients was analyzed. Results: Balance dysfunction significantly improved after the first CCRM treatment and was completely alleviated after two CCRM treatments. PSTN was transformed to gaze-evoked persistent torsional nystagmus after the first CCRM treatment, and the degree of nystagmus was reduced. PSTN stopped in subsequent CCRM treatments. The severity of the vertigo gradually reduced after each treatment. The clinical manifestations of these patients after one or three CCRM treatments were the same as those of BPPV patients. Vertigo, PSTN, and imbalance were alleviated entirely in all patients after several CCRM treatments, suggesting that these patients had atypical BPPV. Conclusions: Sudden-onset vertigo associated with PSTN and imbalance is a unique clinical manifestation of BPPV, caused by the canalith jam in the posterior semicircular canal or otolithiasis in multiple semicircular canals. The CCRM treatment is an effective therapeutic method for sudden-onset vertigo associated with PSTN and imbalance when central vestibular vertigo was excluded.