Denervation of Muscle in Myasthenia Gravis

Abstract

A patient with symptoms of myasthenia gravis for 47 years was found on biopsy to have large groups of small, angulated muscle fibers. Fenichel and Shy recently observed groups of small muscle fibers in myasthenia gravis and considered this lesion indicative of a denervating process in this disease.¹ In the present case, the diagnosis of denervation was supported by histochemical studies. This case provides additional evidence that advanced signs of denervation may occur in long-standing myasthenia gravis. Report of a Case Clinical History.—A 50-year-old unmarried female (NIH No. 04-69-46), working as a secretary, was admitted to the National Institute of Neurological Diseases and Blindness with a chief complaint of drooping eyelids (Fig 1). Her illness began at the age of three years, when ptosis of one eyelid suddenly developed. After several years the ptosis disappeared spontaneously, but the opposite eyelid began to droop. When the patient was 10