Contralateral conjugate eye deviation in acute supratentorial lesions.

BACKGROUND: Conjugate eye deviation (CED) in patients with acute supratentorial lesions is generally directed ipsilateral to the lesioned hemisphere. Incidentally, CED occurs to the contralateral side. We report five new cases and review previously published reports to elucidate the lesion responsible for and the mechanism underlying this phenomenon.

CASE DESCRIPTIONS: In a prospective study of 133 consecutive patients with CED caused by an acute supratentorial lesion, 5 patients showed contralateral CED. This was caused by an intracerebral hemorrhage located thalamic (n = 2), frontoparietal (n = 1), and frontoparietotemporal (n = 1). In 1 patient the cause was a subdural hematoma, an association that has not been reported earlier. Four of the 5 patients died. All patients had clinical signs of rostral brain stem dysfunction and a shift of midline structures on computed tomographic scan or at autopsy.

CONCLUSIONS: Contralateral CED is always associated with hemorrhagic lesions, most commonly in the thalamus. The prognosis of patients with this sign is generally poor. Involvement of descending oculomotor pathways from the contralateral hemisphere at midbrain level is the most probable explanation for this phenomenon.