Knowledge of Refraction and Muscular Anomalies Essential to the Successful Treatment of Nervous Complaints PAGE Popular Errors in regard to Near-Sight Pathological Conditions in Myopia Complicated Systems of Muscles co-operating in Binocular INTRODUCTION.* PAINS spreading to parts contiguous to the eyes, as the result of strain to those organs, in much the same manner as pain from a wound extends to the environing tissues, have long been observed. In many of the older treatises on the diseases of the eye, headaches, nausea, and vertigo are mentioned as parts of that group of symptoms which we now designate as asthenopia. It is to be remembered that the phenomena of accommodative asthenopia, while recognized, were, until its nature and causes were more fully explained by Donders in his remarkable work published in 1864, described under different names, such as hebetudo visus, amblyopie presbytique, etc., and were by many supposed to possess a distinct pathology, such as hyperæmia of the retina, or an increase of some of the humors within the eye. There was a general agreement, however, in the grouping of the phenomena and in regarding excessive or disadvantageous use of the eyes themselves as the exciting cause. The grouping consisted, as it now consists, of pain, tension in the * Submitted to the Royal Academy of Medicine, July, 1886. |