Eye strain from convergence insufficiency.
Eye strain and headache are common ocular symptoms, and the main cause in persons aged 15 to 40 is convergence insufficiency. It is more common in females than in males. Many patients are supplied with glasses for eye strain without the causative convergence insufficiency being treated. The treatment in most cases is orthoptic exercises.
D000065:Accommodation, Ocular; D000293:Adolescent; D000328:Adult; D001248:Asthenopia / Q000209:etiology*; D003937:Diagnosis, Differential; D005128:Eye Diseases / Q000150:complications; D005260:Female; D006261:Headache / Q000209:etiology*; D006801:Humans; D008297:Male; D009988:Orthoptics; D013285:Strabismus / Q000175:diagnosis