GEORGE H. CLARK, M. D.
The term “weak sight” covers a vast amount of ignorance on the part of many doctors, and a multitude of distressing symptoms in many patients.
So much is now known of asthenopia and the parts involved, that it is inexcusable in any one to treat a patient by glibly informing him his sight is weak, and that all that is requisite is medicine. in some cases medicine alone is all that is required; nut in buy far the large majority abnormal refraction, plus the constitutional tendency, are the disturbing factors, and in these medicines and the correcting lenses are required.
The term “asthenopia” should be confined to (1). Muscular asthenopia; a condition in which there is not sufficient power in the lateral recti muscles to keep up the necessary convergence of the visual axes for near vision. This form is usually found in high degrees of myopia, where it is necessary to bring objects very near to the eyes; hence, where more convergence is required.
(2). Accommodative asthenopia. This is a marked condition in many cases of hypermetropia, and is due to disturbances in the ciliary muscle, the muscle of accommodation.
Both forms of asthenopia are sources of much pain and discomfort when using the eyes, particularly for small objects. The first mentioned has a tendency to increase the already high degree of myopia, and eventually vision may become so reduced that it is incumbent upon us to give such cases the closest attention.
Either form may appear at times without any manifest myopia or hypermetropia.
In muscular asthenopia the difficulty is due to convergence being in excess of accommodation. If the difficulty be not corrected by the appropriate lenses, divergent strabismus will result. In accommodative asthenopia, accommodation is in excess of convergence, and here we may have convergent strabismus.
In order to cure strabismus, in many instances it is only necessary to correct the visual defect by glasses.
Accommodative asthenopia presents the following symptoms: In attempting to see small objects, the power of the ciliary muscle, owing to the tension required, soon becomes exhausted. There will then follow blurring and dazzling of vision, photophobia, sensation of fatigue in the eyes, supraorbital and temporal pains, congestion, lachrymation, sensation of smarting and roughness, as if sand were beneath the lids.
Inflammation of the lids, with agglutination may follow. In muscular asthenopia, in attempting to fix the vision on small objects there will follow a sensation of strain, double vision, and finally one eye will be seen to diverge from the visual axis.
As has been said above, the symptoms will vary according to the condition of the patient. In some there will be no other symptoms than those immediately referable to the eyes; in others, disturbances of the general system will be present.
From this we can readily see that more than the correcting lens is necessary.
The proper treatment of this affection affords an excellent illustration of the difference between old school methods and treatment of disease by law; the superiority of similia over contraria.
The allopath assumes that it is only necessary to treat the symptoms by local treatment, and in order to overcome the trouble in the ciliary muscle-which is usually spasm-uses a solution of atropine to paralyze that muscle, and thus often does his patients harm. Frequently he resorts to the use of the knife when the lateral muscles are affected.
The follower of Hahnemann, on the other hand, diligently searches for the remedy that will produce a similar condition, and after giving the requisite glasses, will usually find among the following, by strictly individualizing, the one that is most suitable. In this, as in all other affections, it is, of course, understood that the symptoms alone are to be the guide in choosing the remedy, and that no pathological ideas are to be permitted to prevail.