Downgaze paralysis due to brainstem infarction: Clinical course in two cases

Abstract

Two cases of middle-aged women with downgaze paralysis from a mesencephalic infarction are presented. Both recovered within a few months to the extent that they could follow a moving target with their eyes in the extreme downward position. Nevertheless, one patient still complained of difficulty when trying to look down, which especially disturbed her during walking. Examination revealed an inability to generate saccadic eye movements downward, while upward saccades were normal. With time she developed a strategy for bringing her eyes relatively rapidly into her lower field of gaze despite a persisting inability to make downward saccades. The other patient was no longer disabled and could make downward saccades, but they were markedly slowed. The observation of absent or incomplete restitution of saccades, when all other types of eye movements had recovered, is consistent with findings in monkeys after isolated downgaze paralysis produced by minimal lesions. In patients who. after a downgaze paralysis, still complain of difficulties in looking down, a residual saccadic eye movement disorder should be considered as a possible cause of the disability.