The child can work on programs which train eye movements, eye coordination, stereo vision, and antisuppression techniques. Therapy always begins at a level where the patient can succeed and gradually increases the visual demands to stretch his range and skill. This patient is working on a diagnostic and training machine called a cheiroscope. It's used to assess binocular stability and alignment and to detect the presence and extent of suppression. Suppression occurs when the patient's brain shuts off an eye by blocking its visual input when the child loses the ability to control his eye aim or alignment.
Suppression is an adaptive neurological response to protect oneself from double vision.
Training on the cheiroscope gives the child important feedback that he is suppressing and allows him an opportunity to gain the binocular control necessary to correct his eye aim and eliminate suppression. Here a therapist works with a child on fusion techniques using a tool called an aperture rule. The patient is asked to look through a window in a slide at a series of targets placed at the end of the instrument. Each eye only sees part of the targets, and the child learns to fuse the two images coming in from her left and right eyes into a single picture. The therapist's role is to coach the child on ways to adjust her visual system to achieve the goal of clear, single vision.