Page:Handbook of Ophthalmology (3rd edition).djvu/53

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COMrLICATIONS IN MYOPIA. 47

an unpleasant dazzling. The retina is quickly fatigued in read- ing, etc.

Upon ophthalmoscopic examination, a black spot appears near the macula lutea, often surrounded by a reddened area (hy}>ersemia or extravasation). Still, F5rster was satisfied that the portion of the retina affected by metamorphopsia was much larger than that in which changes were ophthalmoscopically visible. From the concentric curvature of the lines Forster supposed that the sensitive elements of the retina were crowded by the pathological process toward the centre of the diseased jmrt.*

While the above-mentioned diseases of the macula lutea at least spare the periphery of the field of vision, it happens much oftener in myopic than in previously healthy eyes, that sight is absolutely destroyed by detachment of the retina.

The complication of myopia with glaucoma will be considered under the head of the last-named disease.

TREATMENT.

A cure for myopia cannot be expected. In the cases of ray- opes who have strained their eyes for weeks or months, one often sees that rest or the use of atropine causes some withdrawal of the far point ; in such cases there has been no change in the con- dition of refraction, but there has been relief to a sjjasm of ac- commodation, which, when discussing hypermetropia, we shall describe as latent accommodation. There is more to be done in avoiding the development of myopia. With this in view, it is all-important to regulate the use of the eyes. Reading, etc., at twilight is to be strictly forbidden; and even with sufficient light, work ujx)n very near objects should not be too steadily pursued. Above all, a strong bending forward of the head is to be avoided. Children with very slight myopia often, in spite of that fact, use persistently an object distance from 4 to 6 inches ; this, of course, involves a strong tension of accommodation, a high degree of convergence and a bowed position of the head. It is the duty of parents and teachers to correct this. If the case is

  • An affection which might well cause this is the retinitis of the external

layer, described by H. Muller. Saemisch (Beitrage zur Anatomic des Auges, 1862) has shown that it also occurs as a circumscribed affection of the macula !utea.