Surachatkumtonekul, ThammanoonPamonvaechavan, Pittaya2009-05-272009-05-272009-03-24Surachatkumtonekul T, Pamonvaechavan P. Unilateral vertical nystagmus: the Heimann-Bielschowsky phenomenon. Journal of the Medical Association of Thailand. 2009 Mar; 92(3): 373-6http://imsear.searo.who.int/handle/123456789/41042Chotmaihet Thangphaet.OBJECTIVE: To present clinical feature of Heimann-Bielschowsky phenomenon and strabismus association. DESIGN: Retrospective case series. MATERIAL AND METHOD: Medical records of cases between January 2004 and January 2008 were reviewed. Eight cases met the criteria. Age, sex, visual acuity, and eye examination data were collected. RESULTS: Six cases were male and two cases were female. Age at presentation ranged from 4 to 45 years old. Seven cases had vision of 6/60 or worse. Only one case had visual acuity 6/36. Strabismus was seen in five cases (exotropia 4 cases and esotropia 1 case). No one had symptoms of diplopia or oscillopsia. All cases had unilateral coarse, slow, pendular vertical oscillations occurring in the poor vision eye. CONCLUSION: Monocular vertical oscillation may develop in an eye with reduced vision. It may be a common condition but under diagnosed.engJournal Article