Nemaline myopathy: an unusual cause of ophthalmoparesis

Ophthalmoparesis and ptosis are extremely rare in nemaline myopathy. A 45-year-old man with a long history of bilateral ptosis and a 1-year history of diplopia is reported. Leg and arm weakness and wasting had been present since childhood, with a very slow deterioration over time. On examination, there was nonfatigueable bilateral ptosis that was more marked on the right. There was diplopia on left gaze. Extraocular movements showed limitation of elevation and adduction of the right eye. There was bilateral facial weakness, as well as proximal and distal wasting and weakness in the arms and legs. Electromyography (EMG) showed a combination of myopathic and neurogenic changes. Triceps muscle biopsy showed small multiple collections of rod-like structures in > 50% of fibers. This patient presented with a clinical picture that did not primarily suggest nemaline myopathy. This case illustrates the heterogeneity of this disorder and the need for muscle biopsy to make an accurate diagnosis in patients with ptosis and progressive external ophthalmoparesis.