Chronic progressive ophthalmoplegia of myopathic origin.

THE term " chronic progressive ophthalmoplegia " signifies a syndrome characterized by a slowly progressive weakness of the external ocular muscles. In the past the term has been applied loosely, for cases have been called chronic progressive ophthalmoplegia which differ from each other in important respects. Thus, in some instances the paralysis has been confined to the levators ofthe upper lids (Fuchs, 1890, and Collins, 1909); in others complete external ophthalmoplegia has been present, notably in the cases of Beaumont (1900), McMullen (1912), Altland (1909), McMullen and Hine (1921). Usually the intrinsic eye muscles escape, but this is not always the case. Sometimes there has been associated weakness of the orbicularis oculi (Beaumont, 1900) and of other muscles of the face and of the limbs (McMullen and Hine 1921). In some there has been no family history, whilst in others the disease has been hereditary (Ayres, 1896; Cooper, 1910; Bradburne, 1912; Crouzon, 1929). The scanty pathological material has shown that the oculomotor nuclei may be the site of degenerative changes in some instances but not in others. In 1900 Wildbrand and Saenger grouped together certain cases of external ophthalmoplegia because they believed them to have characteristics which separated them from a congenital type on the one hand and a type symptomatic of neurological disease extending beyond the oculo-motor territory on the other. This group, which they separated, they believed formed a clinical entity which had the following characteristics : the onset was usually in infancy or early childhood; the progress was very slow, extending over periods as long as 30 or 40 years; ptosis was usually the first sign, to be followed by increasing restrictions of the external ocular movements, typically without diplopia; the paralysis might halt for long periods, but as a rule complete fixation of the eyeballs was the final state, though the ptosis was seldom complete. The pathology underlying the symptoms of this group still remains a problem. Nuclear degenerative changes have been thought to be the cause of the paralysis, but im the absence of conclusive proof, notably by Cooper (1910) and Crigler (1914). The term " chronic progressive nuclear ophthalmoplegia " has been applied to those cases showing a slowly increasing oculo-motor palsy which is presumed to be due to degeneration ofthe cells of the 3rd, 4th, and 6th cranial nerve nuclei. The few published accounts of this condition have been reviewed by Wildbrand and Saenger (1900): in some of the cases studied degenerative changes have been found in the oculo-motor nuclei; but even so it has been impossible to determine if the degeneration has been primary, or secondary, to some other disease process. The syndrome of gradually increasing oculo-motor paralysis may certainly be produced in several ways. It may be the first sign of disease involving muscles