A Case of Ocular Myasthenia Gravis Presenting as Double Depressor Palsy
A 65-year-old man who had been experiencing diplopia in front and down gaze for 15 days visited our hospital. His medical history revealed no contributing factors such as diabetes mellitus, hypertension, and cerebral ischemic attack. Ophthalmic examinations revealed normal vision in both eyes and no abnormal pupillary reflex. Fourteen prism diopter hypertropia was noted in the patient's left eye and limitation of depression was found in the adduction, primary gaze, and abduction (). Forced duction test revealed no restriction. Brain magnetic resonance imaging showed no remarkable findings. Two weeks after the first visit, the patient complained of ptosis in the left eye. An ice test was performed and the ptosis was resolved after the test (). Then, anti-acetylcholine receptor binding antibody levels were checked and found to be slightly elevated (0.416 nmol/L). We prescribed methylprednisolone per os 24 mg for 2 weeks, and his symptoms improved after 2 weeks. Three weeks after medication, the patient showed an ortho result in the alternate prism cover test, normal ocular movements, and complete resolution of diplopia ().