Eight patients, who are otherwise normal, presented with a clinical syndrome of episodic unilateral mydriasis. Episodes are of various lengths in different patients and occur at random intervals. Head pain and blurring of vision are typical. There is no ocular muscle palsy or lid involvement. Prognosis appears good. There are various syndromes which include the feature of episodic unilateral mydriasis.
Hallett M, Cogan DG. Episodic Unilateral Mydriasis in Otherwise Normal Patients. Arch Ophthalmol. 1970;84(2):130-136. doi:10.1001/archopht.1970.00990040132002