The VDC Blog

Strabismus 1/13/10

Strabismus is a fancy word for eye turn. Whether the eye turns in or out, is constant, intermittent, alternates between each eye or not, it all falls under the general term of strabismus. It occurs mainly due to the following things, either the eye fails to have full range of motion(eye muscle problem), the information received through the eye does not correlate with the other eye(brain processing problem), or the visual system was "built" on a fragile foundation(developmental/gross motor problem). There are a small percentage of people who have strabismus due to structural eye muscle abnormalities. More commonly, those with strabismus fall under the other two categories.
The requirements for clear, single, binocular vision in all positions of gaze are very precise. We begin to learn how to coordinate our eyes during infancy. Sometimes, even for no reason, the wiring between eyes and brain get misguided. This does not exclusively mean eyesight, which is why those strabismics who have good eyesight in the strabismic eye still have an eye turn. For them, it doesn't have to do with clarity, it's about quality.
In addition to learning eye coordination, infants begin to learn body coordination and how that coordination relates to their spatial environment. 'If I can move this arm then I can reach this toy.' These gross motor developments lay the foundation for more precise fine motor developments such as hand and eye movements. It is commonly found in a strabismic patient that the eye turn is not the problem but a symptom of a weakly developed or fragile gross motor system usually on the same side of the body as the eye turn. Directing therapy only to the eye turn treats the recurring symptom instead of the cause. Thus therapy that is targeted first at controlling and directing body movement on the weaker side with only the strabismic eye. Then directing body movement with both eyes is much more beneficial.