Pseudotumor cerebri sine papilledema with unilateral sixth nerve palsy

A 17-year-old woman presented with a history of 1-week of headache and 3 days of horizontal diplopia. Examination revealed 20/20 vision in both eyes, no papilledema, and an abduction deficit in her left eye. Lumbar puncture revealed an opening pressure of 440 mm H2O. After treatment with acetazolamide, the headache and abduction deficit resolved. Papilledema never developed. This is a unique case of pseudotumor cerebri sine papilledema with a unilateral abduction deficit. We suggest that young women with headache and unilateral abduction deficits may be unrecognized cases of pseudotumor cerebri.