Pediatric Vision Disorders
Kids and Contact Lenses (2)

2. Anisometropia
This is a special refractive condition for which children may be fit with contact lenses. Again, spectacles may cause distortion and prismatic effects for some young patients. The anisometropic patient may also face some unique problems with spectacles. Due to the dioptric difference between the two eyes, spectacle correction often results in differing image sizes. This, in turn, leads to spectacle-induced aniseikonia.

Ocular images that differ in size, clarity or luminance can compromise fusion. Discomfort, suppression or poor stereopsis may result. Once again, cosmesis is a factor because the patient�s eyes appear to be different sizes.

Contact lenses help eliminate the differences between interocular image sizes. They allow the patient to enjoy improved fusion, visual development and stereopsis.

3. Aphakia
Aphakia results when the crystalline lens is surgically removed due to infantile cataracts, or other medical factor. Depending upon the circumstances, either unilateral or bilateral aphakia can exist
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The resultant high hyperopia makes spectacles extremely impractical for the infant. Aphakic patients require a high prescription, and unless the child looks through the center of the lenses, he or she will experience extreme distortion.

Some pediatric aphakes require a high plus in one lens but less plus power in the other. The two eyes see different image sizes, compromising visual development. Contact lenses can reduce that problem, just as they would with another highly hyperopic child.

4. Nystagmus
When evaluating a nystagmoid patient, you need to determine type of nystagmus, direction, frequency and whether the nystagmus is dampened or eliminated in a particular gaze (null point).

Sometimes you�ll find the null point, but the patient cannot take advantage of it. Specifically, the null point may be outside the optical center or perhaps the entire range of the spectacle lens. This is an indicator that spectacles won�t work for that patient.

Alternatively, contact lenses allow the patient to view objects in the null point position and still benefit from refractive correction.

Albinism and aniridia
Patients with albinism or aniridia may experience extreme glare, which results in reduced visual acuity. A contact lens with a central tint and an opaque peripheral zone would reduce glare and photophobia in these patients, thus improving visual acuity. The former acts as a light filter, while the latter creates an artificial pupil.

Corneal Injury
Ocular injury can leave the corneal surface with significant distortion, resulting in degraded retinal images. In such instances RGP lenses can reestablish regularity to the eye�s front refracting surface.

Children are just as vulnerable to corneal injury as adults. However, some doctors hesitate to discuss contact lens options for these children and simply prescribe glasses.

Amblyopia and Strabismus
Many amblyopic and strabismic patients have occlusion therapy to improve their visual acuity or binocularity. While patching can be effective, children aren�t always eager to comply. Discomfort or diminished cosmesis are often the reasons. Even when a child wears a patch, we can�t always tell whether the child is �peeking� around it, thus defeating the purpose of this occlusion therapy. Occluder contact lenses can be used, with opaque central regions of various sizes on such patients The results: enhanced cosmesis, less self-consciousness and increased compliance.

Elective Fits
Younger patients are occasionally fit with contact lenses purely for cosmetic reasons. If they�re highly motivated, some do extremely well. While others become quickly discouraged by both the fitting and adaptation processes.