Ocular Myopathy

Abstract

Although primary involvement of the ocular muscles was recognized as a distinct entity many years ago by Gowers,1 other observers have followed Moebius'2 claim that the resulting weakness was due to nu-$ clear degeneration. In 1951, however, Kiloh and Niven3 extensively reviewed the pertinent literature, presented five cases, and concluded that these entities were similar in their pathology, namely, primary disease of the ocular muscles. These observations have since been confirmed by biopsy of involved muscle4,5 and from autopsy material.6,7 The term ocular myopathy is now, therefore, in general usage for such cases. In this study, the clinical, and in particular the electromyographic, findings are presented in six patients with the diagnosis of ocular myopathy. I. Clinical Findings Report of CasesCase 1.\p=m-\Ten years ago, this 54-year-old patient first noticed drooping of the right lid and double vision. Examination revealed complete right ptosis, without compensatory contraction of the frontalis muscle, and right external ophthalmoplegia. There was left exotropia, but the move¬ ments of the left eye were full except for paralysis of the medial rectus. Bilateral facial weakness was most marked in the upper muscles and on the right side. The remainder of the neurological examination was unremarkable. Biopsy specimens from the right and left medial rectus muscles revealed muscle-fiber degeneration of a nonspecific nature. Recording electrodes were inserted into the right lateral rectus, left medial rectus, right lower facial muscles, and both orbicularis oculi muscles.Case 2.-This 13-year-old girl's present illness commenced seven years ago, at which time droop¬ ing of the right lid was noted. This progressed; ptosis developed on the left, and she subsequently experienced difficulty in moving her eyes. On examination, vision was 20/80 in each eye, and she had a fundus pattern suggesting retinitis pig¬ mentosa. There was bilateral external ophthalmoplegia and almost complete bilateral ptosis, without any compensatory contraction of the frontalis. In addition, she had bilateral facial weakness, with striking involvement of the orbicu¬ laris oculi. The remainder of the neurological system was intact. Biopsy of the left medial rectus revealed a marked increase in fibrous tissue, a slight increase in sarcolemmal nuclei, and wide¬ spread uniform atrophy of muscle fibers. Con¬ centric needle electrodes were inserted into the left medial rectus and lower facial muscles.Case 3.-At the age of 13, this 35-year-old man had developed drooping of both upper lids. This progressed, and he subsequently has experi¬ enced difficulty in moving his eyes, dysarthria, and dysphagia. On examination his speech was noted to be nasal in character. There was weakness of the muscles of mastication and deglutition. The tongue was also weak, but not wasted, and no fibrillations were observed. There was bilateral exotropia and ptosis, the latter being without compensatory contraction of the frontalis. Ocular movements were paralyzed except ...

Ocular Myopathy

“…Histology of biopsies and post-mortem material [6][7][8][9][10] and electromyographic studies [11,12] confirmed this conclusion.…”

“…15. 39, 40] together with pigment degeneration of the retina [13][14][15][16] or with pigment degeneration of the retina alone [12,16,41,42]; (d) ocular myopathy combined with CNS disturbances [17. 51J; (e) variants of ocular myopathy combined with choroidal degeneration [10,13], other ocular changes [11,45] or gonadal insufficiency [ 14.…”