Ocular myopathy is better known in the ophthalmic and neurologic literature as "chronic progressive nuclear ophthalmoplegia" or as "chronic progressive external ophthalmoplegia." The various terms stem from differences in opinion as to what constitutes the basic pathologic process. The older concept of nuclear origin in this entity1,2 was that of a degeneration of the nuclei of the oculomotor, trochlear, and abducens nerves. However, more recent pathologic studies3-6 indicate that this conclusion is not justified. Sorsby7 is of the opinion that ocular myopathy bears no relationship to motor neuron disease but is a form of muscular dystrophy. The pathologic data accumulated to date indicate that "chronic progressive external ophthalmoplegia" may rightly be considered as an "ocular myopathy," which is well summarized by Kiloh and Nevin.4
While uncommon, cases of progressive muscular dystrophy are reported in which the ocular muscles and muscles of the eye-lids have been involved.
ERDBRINK WL. Ocular Myopathy Associated with Retinitis Pigmentosa. AMA Arch Ophthalmol. 1957;57(3):335-338. doi:10.1001/archopht.1957.00930050345003