| Abstract: | A 24-year-old man, left eye enucleated at the age of ten months, had jerk-right nystagmus with increasing amplitude in abduction and null position in near-extreme adduction. Under occlusion or in darkness, the nystagmus changed to jerk-left, the amplitude increased in adduction and null position was in abduction; as if his left eye had nystagmus blockage syndrome and he was seeing with this absent left eye! The difference between nystagmus blockage syndrome and latent nystagmus is discussed: nystagmus blockage syndrome is manifested by ‘motor’ maneuver of adduction and abduction, whereas latent nystagmus is induced with ‘sensory’ maneuver of occlusion. It suggests that nystagmus blockage syndrome and latent nystagmus may arise from different mechanisms despite their frequent concurrence. |
