Strabismus – “Eye Turn”
What is an “Eye Turn” or Strabismus?
Strabismus, often referred to as an “eye turn” or “cross-eye,” is the improper alignment of the eyes. The turning of one or both eyes is often thought to be due to the lack of coordination between the muscles of the eyes. However, the extraocular eye muscles are often fine. The eyes are unable to point in the same direction due to the brain’s misconception of “where am I” and “where is it (the object).” This can result in double vision (the appearance of two images inaccurately overlapping). Alternatively, to avoid visual confusion, the brain may maladapt and learn to suppress the image seen by the turning eye. If an eye turn becomes constant in one eye, this can cause a decrease in vision known as strabismic amblyopia. Please see “Amblyopia” for more information. This can cause binocular vision dysfunction and a lack of depth perception. Infancy and young childhood are the best times to seek help from a developmental optometrist. During these times, development of the visual system is highly active and providing early treatment raises the chance of permanent vision correction.
What are the symptoms of Strabismus?
Parents often will first notice that their child has one eye that looks like it is turned inward or drifts outward intermittently or constantly throughout the day. Other symptoms may include squinting, shutting, or covering an eye, a head turn or tilt while watching TV, impaired depth perception (3D) such as fear of going downstairs or escalators or dislike for 3D movies, poor eye-hand coordination such as trouble catching or hitting a ball, clumsiness, loss of place while reading, slow reading speed and comprehension, reversing numbers and letters, or attention problems.
How is Strabismus treated with Optometric Vision Therapy?
An optometric vision therapy program is the least invasive/non-surgical treatment for strabismus that helps reduce eye misalignment and trains the brain to use both eyes simultaneously by merging the images seen by each eye into a single 3D image. The vision therapy program sets up the conditions to reinforce proper neurological pathways to ensure good eye teaming skills in all gazes and distances. Eyeglasses or contact lenses may boost the effects of vision therapy and may be a necessary part of treatment to help straighten the eye if prescribed by the doctor. Vision therapy makes use of lenses, prisms, filters, and other specialized equipment during the treatment program. The length of the program can range from several weeks to several months, depending on the severity of the diagnosis and patient compliance.
What about strabismus surgery? Eye muscle surgery performed by an ophthalmologist alters the outside eye muscles to compensate for the difficulty with eye-brain coordination. For some patients, eye muscle surgery may be a necessary part of treatment. However, we recommend that the patient is evaluated by a developmental optometrist to help determine if the eyes can be successfully aligned AND if two-eyed depth perception can be achieved after surgery. Depth perception is the glue that keeps the two eyes together post-surgery, otherwise additional surgeries may be needed to maintain cosmetic eye alignment. It is best if eye surgeons and developmental optometrists work together to best achieve the patient’s goals.