b. Operative Procedures.
(1) Discussion, or needling of lens. The capsule is incised and the lens
substance is broken up. The aqueous humor exerts a solvent action on the exposed
lens tissue, thus a clear opening for the passage of light is obtained. The principal use
for needling is in cases of cataract due to trauma and in cataract surgery performed on
children.
(2) Iridectomy. A sector of the iris is removed as a preliminary step in
extraction of the cataract (lens extraction).
(3) Lens extraction, intracapsular. The entire lens within the capsule is
removed intact through a corneoscleral incision (see figure 1-4).
Figure 1-4. Intracapsular lens extraction.
(4) Lens extraction, extracapsular. The anterior capsule is cut, and the lens
substance is delivered through the opening in the capsule. The posterior lens capsule
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