Asymmetric optokinetic afterresponse in patients with small acoustic neurinomas

Research output: Contribution to journalArticle


Directional asymmetry of primary and secondary optokinetic afternystagmus (OKAN I and OKAN II, respectively) was studied in 20 patients with small acoustic neurinomas (< or = 20 mm), and results were compared to those for 24 normal controls. The optokinetic afterresponse was induced by 60 s of horizontal whole-field optokinetic stimulation in both directions. Among patients, the optokinetic afterresponse was asymmetric, OKAN I and OKAN II beating toward the lesioned ear being significantly weaker than the OKAN I and OKAN II beating toward the healthy ear. Hence, in these patients with gradual deterioration of vestibular function, the vestibular side-difference was reflected both in OKAN I and OKAN II. Although asymmetry in OKAN I was frequently observed among controls, it was significantly more pronounced among the patients. Moreover, patients could be distinguished by the occurrence of OKAN II, as it did not occur at all among controls exposed to the same stimulation.


External organisations
  • Skåne University Hospital
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Otorhinolaryngology


  • Adult, Aged, Caloric Tests, Female, Humans, Male, Middle Aged, Neuroma, Acoustic, Nystagmus, Optokinetic, Vestibule, Labyrinth, Journal Article, Research Support, Non-U.S. Gov't
Original languageEnglish
Pages (from-to)299-307
Number of pages9
JournalJournal of Vestibular Research: Equilibrium and Orientation
Issue number3
StatePublished - 1990 Jan 1
Publication categoryResearch