Oculographic analysis of acute esotropia secondary to a thalamic hemorrhage

We used electrooculography to study the saccadic velocities, smooth pursuit, and vestibular ocular reflex in a patient with an acute thalamic hemorrhage. Our findings confirmed what others have shown in that there were hypometric saccades contralateral to the lesion, impaired smooth pursuit ipsilaterally, and a preserved vestibular ocular reflex. In addition, we demonstrated an asymmetry with the contralateral eye being more affected. It is also shown that the "convergence" movements seen on attempted upgaze are typical of saccades and not vergence movements. A discussion of possible pathophysiologic mechanisms with review of other studies is presented.