Cataract

(kat' '-ar-akt). Diminished transparency or an opacity of the crystalline lens, or of its capsule. C, Artificial Maturation of, Porster's Method consists in friction of the cornea against the lens by pre ure upon the cornea. Beltmanri s Method consists in " direct trituration ' ' of the lens with a spatula introduced into the anterior chamber. Both methods are preceded by an iridectomy. C, Black, the lens is pigmented, and of a dark-brown color. C, Capsular, consists in non-transparent deposits on the inner surface of the capsule. C, Cortical, opacification of the outer layers of the lens. C, Diabetic, is a ociated with diabetes. C, Disci ion of, an operation preliminary to absorption, or extraction by suction, consisting in rupturing the capsule, so that the aqueous humor gains acce to the lens. C, Extraction of, removal of the cataractous lens by surgical operation. See Extraction of C. C, Fluid, C., Lacteal, the breaking up of an opaque lens into a milky fluid. C, Green, a name given to a grayish green reflex seen in glaucoma; it is also seen when the pupil is dilated and at the same time the media are not completely transparent. C, Immature, or Unripe, only a part of the lens-substance is cataractous. C, Lacteal. See C, Fluid. C, Lamellar, or Zonular; certain layers between the cortex and nucleus are opaque, the remaining layers being transparent. C, Mature, or C, Ripe, the whole lens-substance is cataractous. C, Morgagnian, when a hyper mature or overripe C. shrinks and leaves a nucleus floating in the di olved outer layers. C, Naphthalinic, an opacity of the lens of a rabbit following the administration of naphthalin. C, Polar (anterior or posterior), the opacity is confined to one pole of the lens. Cpricker. See Cataract-pricking. C. -pricking, a name given to the old method of artificial luxation of the lens in cases of cataract. A needle was pa ed into the sclera on the outer margin of the cornea and into the lens. which was then depre ed into the vitreous. Those who performed this operation were called cataract prickers. C, Pyramidal, the opacity is at the anterior pole and is conoid, the apex extending forward. C, Recurrent Capsular, or Secondary, capsular cataract, appearing after the extraction of the lens. C, Senile, the cataract of old persons, the most frequent form, and that understood when not specified as congenital, juvenile, traumatic, soft, etc.