. A treatise on the diseases of the eye. displacement of some of the cornealelements, and also, perhaps, to a disturbance of the nutrition of the corneafrom the compression of the nerves. We meet with a very superficial opacity of the cornea, which is due tochanges in the epithelial layer. Here and there the epithelial cells becomethickened, aggregated together, and opaque, their contents having perhapsundergone fatty degeneration. These opacities are of a faint gray, or bluish-gray color, with an irregular margin. In their centre, the reflection of anobject, for instance the bars of a window,
. A treatise on the diseases of the eye. displacement of some of the cornealelements, and also, perhaps, to a disturbance of the nutrition of the corneafrom the compression of the nerves. We meet with a very superficial opacity of the cornea, which is due tochanges in the epithelial layer. Here and there the epithelial cells becomethickened, aggregated together, and opaque, their contents having perhapsundergone fatty degeneration. These opacities are of a faint gray, or bluish-gray color, with an irregular margin. In their centre, the reflection of anobject, for instance the bars of a window, will be found indistinct, or moreor less distorted. Generally, the opacities are easily observable. They may,however, be so slight as to escape detection, except with the oblique illumi-nation, Avhen they become very evident. They are chiefly met with as theresult of the superficial forms of keratitis, especially pannus due to distichi-asis or granular lids, and also of the superficial ulcers of the cornea. OPACITIES OF THE CORNEA. 243. After Dalrymple.] The deeper opacities, which are situated in the substance of the corneaitself, may be confined to a certain portion of it (partial leucoma) [Fig. 87],or extend over its whole surface (total leucoma). The cloudiness may eitherbe of a uniform grayish-blue, or grayish-white color, or may be made up ofseveral opaque, white patches or spots of varying extent and shape. Theoutline of these opacities is irregular and not sharply defined, being shadedgradually off into the normally transparent cornea. Their thickness andcolor also vary much, from a grayish-blue to a yellowish-white and densely [Fig. tint. The epithelial layer isoften irregular and punctated, as if afine powder had been dusted over it,and this causes a distortion of the re-flected image. Or, again, the opaci-ties may look like little opaque, chalkynodules strewn about on different por-tions of the cornea (generally near itssurface^, and are the remains of phl
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Keywords: ., bookcentury1800, booksubjecteye, booksubjecteyediseases, bookyear
