Abstract

Case 1. A 34 year old man complained of oscillopsia after 1 month of total parenteral nutrition. Weakness of medial and lateral rectus was noted in both eyes. There was gaze-evoked nystagmus occurring in almost all directions except for in the primary and secondary down gaze. Brain MRI revealed homogenously enhancing linear midline lesions extending continuously from pretectum to medulla in the dorsal parts, which seemed to involve the neural integrator of both vertical / torsional and horizontal gaze. Oculomotor and MRI abnormalities disappeared completely 1 month after thiamine injection.
Case
2. A 28-year-old woman developed general weakness, confusion, and oscillopsia after 2 months of hyperemisis gravidarum. There was no weakness of extraocular muscles. However, there was gaze-evoked nystagmus in almost all directions except for in the primary and secondary down gaze. MRI findings are compatible with those of Wernickes encephalopathy. Both vertical / torsional and horizontal neural integrators were involved. Gaze-evoked nystagmus revsolved 25 days after thiamine injection. Both cases indicate that Wernickes encephalopathy can cause multidirectional gaze-evoked nystagmus when neural integrators both for