Oculomotor nerve palsy as an initial manifestation of polycythemia vera.

In polycythemia vera (PV), even though thrombotic complications are common, ophthalmoplegia rarely occurs, and oculomotor nerve palsy has not been described as an initial manifestation. We present a 53-year-old woman who developed right oculomotor nerve palsy and investigation disclosed PV as the cause of ophthalmoplegia. MRI also revealed an acute silent infarction in the right frontal subcortex. PV may manifest with oculomotor nerve palsy owing to a thrombotic complication and should be considered in the differential diagnosis of acute ophthalmoplegia.