<unk>  is the usual cause of eye strain headache that begins abruptly with use of the eyes in which there is a normal ophthalmologic exam. ICD classification: F45.8<unk>  ocular
Ocular neurosis
Cat eye syndrome
Ocular ischemic syndrome
Ocular myasthenia
Ophthalmodynia periodica
Dry eye syndrome
Ocular melanosis
Computer vision syndrome