Metamorphopsia as an initial complaint of idiopathic intracranial hypertension.

We examined 4 patients in the past 6 years who were first seen at our institution because of metamorphopsia and who were eventually diagnosed as having idiopathic intracranial hypertension (IIH). Idiopathic intracranial hypertension is a condition of elevated intracranial pressure that occurs primarily in young women. Neuroimaging findings and cerebrospinal fluid (CSF) indices are normal. Its cause is unknown, but recent weight gain is nearly universal. Symptoms include headache, pulse-synchronous tinnitus, visual obscurations, and diplopia. Most patients have papilledema, and they may have sixth nerve palsies. Optic nerve dysfunction can occur if the papilledema is severe or prolonged.