Dissociated ipsilateral horizontal gaze palsy in one-and-a-half syndrome: a clinicopathologic study.

We report a patient with a one-and-a-half syndrome due to an isolated small infarction in the left rostral part of the paramedian pontine reticular formation and the ipsilateral medial longitudinal fasciculus. Oculocephalic movements toward the left were preserved (dissociated ipsilateral horizontal conjugate gaze palsy).