Emergence of diplopia and oscillopsia due to Heimann-Bielschowsky phenomenon after cataract surgery.

The Heimann-Bielschowsky phenomenon (HBP) refers to coarse vertical oscillation of the eye with impaired vision. The ocular movements are strictly monocular, occurring only in the eye with amblyopia. The vertical oscillation is of equal velocity in both vertical directions, or may sometimes be greater in the downward than upward direction. HBP develops several years after loss of vision. It can be differentiated from dissociated nystagmus in spasmus nutans, congenital nystagmus and internuclear ophthalmoplegia based on the strict unilaterality, vertical direction and low frequency. Previously, only a few reports described the development of oscillopsia due to HBP after cataract surgery, which resolved spontaneously or responded to gabapentin. However, visual impairments due to diplopia or oscillopsia from HBP after cataract surgery have received little attention. We report a man who developed persistent vertical diplopia and oscillopsia due to HBP after a cataract operation, which markedly impaired his vision.