The complications seen in children after lens extraction are different from those in adults. Retinal detachments, macular edema, and corneal abnormalities are rare in children. The incidence of postoperative infections and bleeding, however, is similar in children and adults. In children, strabismus is very commonly associated with cataracts. The risk of glaucoma is increased in children who have surgery in infancy, and glaucoma often develops many years after lens extraction (see Chapter 22).

Visual Outcome After Cataract Extraction

Visual outcome after cataract surgery depends on many factors, including age of onset and type of cataract, timing of surgery, choice of optical correction, and treatment of amblyopia. Early surgery by itself does not ensure a good outcome. Optimal vision requires careful, long-term postoperative management, particularly regarding amblyopia. But even when congenital cataracts are detected late (after age 4 months), cataract removal combined with a strong postoperative vision rehabilitation program can achieve good vision in some eyes.

Structural or Positional Lens Abnormalities

Congenital Aphakia

Congenital aphakia, the absence of the lens at birth, is rare. This condition is usually associated with a markedly abnormal eye.

Spherophakia

A lens that is spherical and smaller than normal is called spherophakic. This condition is usually bilateral. The lens may dislocate and prolapse into the anterior chamber (Fig 23-7), causing secondary glaucoma.

Figure 23-7 Spherophakia with lens dislocation into anterior chamber, left eye.

Coloboma

A lens coloboma (a misnomer) involves flattening or notching of the lens periphery. A lens coloboma can be associated with a coloboma of the iris, optic nerve, or retina, all of which are caused by abnormal closure of the embryonic fissure. Lens colobomas are usually located inferonasally. Zonular fibers are typically absent or stretched in the colobomatous area, resulting in a flattening of the lens in that location, without any dislocation. In more significant colobomatous defects, lens dislocations may occur superiorly and temporally (Fig 23-8). Most colobomatous lenses do not worsen progressively.