RT Journal Article SR Electronic T1 Recurrent spontaneous vertigo with interictal headshaking nystagmus JF Neurology JO Neurology FD Lippincott Williams & Wilkins SP e2135 OP e2145 DO 10.1212/WNL.0000000000005689 VO 90 IS 24 A1 Lee, Sun-Uk A1 Choi, Jeong-Yoon A1 Kim, Hyo-Jung A1 Kim, Ji-Soo YR 2018 UL http://n.neurology.org/content/90/24/e2135.abstract AB Objective To define a disorder characterized by recurrent spontaneous vertigo (RSV) of unknown etiology and interictal headshaking nystagmus (HSN).Methods We characterized HSN in 35 patients with RSV-HSN compared to that recorded in randomly selected patients with compensated vestibular neuritis (VN), vestibular migraine (VM), and Ménière disease (MD).Results The estimated time constant (TC) of the primary phase of HSN was 12 seconds (95% confidence interval [CI] 12–13) in patients with RSV-HSN, which was larger than those in patients with VN (5 seconds, 95% CI 4–5), VM (5 seconds, 95% CI 5–6), or MD (6 seconds, 95% CI 5–6). TCs of the horizontal vestibulo-ocular reflex were also larger during the rotatory chair test in patients with RSV-HSN. Among the 35 patients with RSV-HSN, 7 showed vigorous long-lasting HSN with a peak slow-phase velocity >50.0°/s. In 5 patients (5 of 7, 71%) with vigorous HSN, HSN could have been induced even with headshaking for only 2 to 5 seconds. Long-term prognosis was favorable, with a resolution or improvement of the symptoms in more than half of the patients during the median follow-up of 12 (range 2–58) years from symptom onset. None developed VM, MD, or cerebellar dysfunction during the follow-up.Conclusion The clinical features and characteristics of HSN in our patients indicate a hyperactive and asymmetric velocity-storage mechanism that gives rise to intermittent attacks of spontaneous vertigo probably when marginal compensation of underlying pathology is disrupted by endogenous or exogenous factors.BRV=benign recurrent vertigo; CI=confidence interval; HIT=head-impulse test; HSN=headshaking nystagmus; MD=Ménière disease; MR=magnetic resonance; MSSQ=motion sickness susceptibility questionnaire; RSV=recurrent spontaneous vertigo; SPV=slow-phase velocity; TC=time constant; VM=vestibular migraine; VN=vestibular neuritis; VOR=vestibulo-ocular reflex; VSM=velocity-storage mechanism