Reversible vertical ocular deviations associated with raised intracranial pressure

Skew deviation is a common neuroophthalmologic finding, the presence of which is classically thought to signify a brainstem lesion. It is frequently seen in conjunction with other posterior fossa abnormalities. We report the cases of five patients having skew deviations with raised intracranial pressure without posterior fossa structural lesions. Whereas skew deviation almost always does indicate intrinsic posterior fossa disease, our experience demonstrates that increased intracranial pressure by itself can cause a skew deviation, probably by causing a secondary brainstem dysfunction.