title: Persistent otolith dysfunction even after successful repositioning in benign paroxysmal positional vertigo.
abstract: To evaluate utricular and saccular function during the acute and resolved phases of BPPV, ocular and cervical vestibular evoked myogenic potentials (VEMPs) were studied in 112 patients with BPPV and 50 normal controls in a referral-based University Hospital. Ocular (oVEMPs) and cervical VEMPs (cVEMPs) were induced using air-conducted sound (1000Hz tone burst, 100dB normal hearing level) at the time of initial diagnosis and 2 months after successful repositioning in patients with BPPV, and the results were compared with those of the controls. Abnormalities of cVEMPs and oVEMPs in patients with BPPV were prevalent and significantly higher compare to the healthy control group (p<0.01 in each VEMP by chi-square test). In the patient group, difference between the proportions of abnormal responses of cVEMP and oVEMP was not significant in both affected (p=0.37, chi-squared test) and non-affected (p=1.00) ears. The abnormalities were more likely reduced or absent responses rather than delayed ones; reduced or absent responses are 17.6% in cVEMPs (p=0.04, chi-square) and 21.6% in oVEMPs (p<0.01). The non-affected ear in the BPPV group also showed significantly higher abnormalities of cVEMP and oVEMP when compared to the control group. The follow-up VEMPs after repositioning maneuvers were not significantly different compared to the initial values from both stimulated affected and non-affected ears. Although most patients had unilateral BPPV, bilateral otolithic dysfunction was often shown by persistently reduced or absent cervical and ocular VEMPs, suggesting that BPPV may be caused by significant bilateral damage to the otolith organs.
authors.affiliation: Department of Neurology, Chonbuk National University School of Medicine, jeonju, South Korea.
authors.forename: Eui-Joong
authors.initials: EJ
authors.lastname: Kim
authors.affiliation: Department of Neurology, Chonbuk National University School of Medicine, jeonju, South Korea; Research Institute of Clinical Medicine of Chonbuk National University, Biomedical Research Institute of Chonbuk National University Hospital, Jeonju, South Korea. Electronic address: ohsun@jbnu.ac.kr.
authors.forename: Sun-Young
authors.initials: SY
authors.lastname: Oh
authors.affiliation: Department of Neurology, Seoul National University Bundang Hospital, Seongnam, South Korea.
authors.forename: Ji Soo
authors.initials: JS
authors.lastname: Kim
authors.affiliation: Department of Neurology, Chonbuk National University School of Medicine, jeonju, South Korea; Research Institute of Clinical Medicine of Chonbuk National University, Biomedical Research Institute of Chonbuk National University Hospital, Jeonju, South Korea.
authors.forename: Tae-Ho
authors.initials: TH
authors.lastname: Yang
authors.affiliation: Graduate School of Flexible and Printable Electronics, Chonbuk National University, Jeonju, South Korea.
authors.forename: Si-Young
authors.initials: SY
authors.lastname: Yang
mesh_terms: D000368:Aged; D065635:Benign Paroxysmal Positional Vertigo / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010037:Otolithic Membrane / Q000503:physiopathology*; D058585:Vestibular Evoked Myogenic Potentials / Q000502:physiology*
keywords: BPPV=benign paroxysmal positional vertigo; Cervical VEMPs; Ocular VEMPs; Saccule; Utricle; VEMPs=vestibular evoked myogenic potentials