title: A comparative study on the observation of spontaneous nystagmus with Frenzel glasses and an infrared CCD camera.
abstract: OBJECTIVE
  To compare the usefulness of a CCD camera with infrared illumination (IR-CCD camera) over Frenzel glasses (F Glasses) for the observation of spontaneous nystagmus, the incidence and direction of nystagmus, and the frequency, amplitude and slow phase of spontaneous nystagmus.
  
  
  METHODS
  One hundred vertiginous patients, fifty-three females and forty-seven males participated in this study. Before undergoing routine neurotological examination, their eye movements were recorded by electronystagmogram (ENG) in conjunction with observations of eye movements under F glasses and through an IR-CCD camera. The data was collected from patients who exhibited spontaneous nystagmus either under F glasses or the IR-CCD camera.
  
  
  RESULTS
  Thirty-three patients showed spontaneous nystagmus under F glasses. On the other hand, under the IR-CCD camera, all patients examined exhibited spontaneous nystagmus. The frequency of nystagmus was not significantly different between these two systems. However, the amplitude and slow phase velocity exhibited significantly larger values under the IR-CCD camera in patients with spontaneous nystagmus both under the IR-CCD camera and F glasses.
  
  
  CONCLUSIONS
  From these observations and evidence, the IR-CCD camera can be recommended as a more useful system and powerful tool for neurotological examination than F glasses.
authors.affiliation: Department of Otolaryngology, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603, Japan.
authors.forename: Shunkichi
authors.initials: S
authors.lastname: Baba
authors.forename: Akiko
authors.initials: A
authors.lastname: Fukumoto
authors.forename: Mio
authors.initials: M
authors.lastname: Aoyagi
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Koizumi
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Ikezono
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Yagi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D004584:Electronystagmography / Q000295:instrumentation*; D005135:Eye Protective Devices; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000295:instrumentation*; D007259:Infrared Rays; D008297:Male; D008875:Middle Aged; D009759:Nystagmus, Pathologic / Q000175:diagnosis*; D014717:Vertigo / Q000503:physiopathology; D014741:Video Recording