title: Ocular Motor Function in Patients with Bilateral Vestibular Weakness.
abstract: BACKGROUND
  Patients with bilateral weakness (BW) have many difficulties in gaze stability that interfere with their normal function. The aim of this study was to evaluate ocular motor functions in patients with BW to better understand the problem of gaze instability in these patients.
  
  
  METHODS
  Patients were referred from the Otolaryngology Department for Vestibular Assessment to our clinic between November 2014 and March 2015. We assessed ocular motor function (gaze, saccade, and smooth pursuit) in patients over the age of 18 years with BW, as verified by a caloric test.
  
  
  RESULTS
  Seventy-eight patients completed all the tests. The mean age of patients was 51.9 (±15.9) years, and 47 (60%) were female. Abnormal results were found in five (6.4%), 32 (41%), and seven (9%) patients with respect to gaze, smooth pursuit, and saccade, respectively. There were positive but relatively weak relationships between age and ocular motor results.
  
  
  CONCLUSIONS
  Patients with BW suffer from dizziness and unsteadiness. These patients have abnormal function in ocular motor (especially smooth pursuit) tests. The ocular motor dysfunction is responsible for gaze instability in static positions such as standing.
authors.affiliation: Department of ENT, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Seyyed Amir Hossein
authors.initials: SA
authors.lastname: Ghazizadeh Hashemi
authors.affiliation: Department of Audiology, School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Sadegh
authors.initials: S
authors.lastname: Jafarzadeh
authors.affiliation: Department of Audiology, School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Majid
authors.initials: M
authors.lastname: Haddadi Aval
authors.affiliation: Department of Audiology, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Reza
authors.initials: R
authors.lastname: Hosseinabadi
keywords: Gaze stability; Ocular motor; Vertigo.