The medical term for “wandering eye” is Strabismus, a common condition where the eyes are not aligned properly and do not look at the same object simultaneously. This failure of binocular coordination prevents both eyes from focusing on a single point, causing the brain to receive two different images and leading to a loss of depth perception. Strabismus affects an estimated two to four percent of the population globally.
Understanding the Types of Eye Misalignment
Strabismus is categorized by the direction the misaligned eye turns. The most common type is Esotropia, where one or both eyes turn inward toward the nose (“crossed eyes”). Conversely, Exotropia describes an outward turn toward the temple (“wall-eyed”).
Misalignment can also occur vertically: upward (Hypertropia) or downward (Hypotropia). The eye turn may be constant (present all the time) or intermittent, appearing only under certain circumstances. Intermittent strabismus often becomes noticeable when a person is tired, sick, or concentrating intently on near tasks. The turning may alternate between eyes or be unilateral, affecting the same eye every time. The degree of deviation ranges from a subtle shift to a highly noticeable turn, affecting both appearance and visual function.
Why Strabismus Occurs
The underlying cause of strabismus is typically a problem with neuromuscular control. Each eye is controlled by six extraocular muscles that must work in precise coordination, receiving signals from the brain to direct movement.
In many childhood cases, the specific cause remains unknown, though a family history is a known risk factor. One common type, accommodative esotropia, is directly linked to uncorrected severe farsightedness (hyperopia). The excessive focusing effort required to see clearly can trigger an involuntary inward turning of the eyes.
Strabismus can also be associated with neurological or genetic conditions that affect the brain’s control centers for eye movement. These include cerebral palsy, Down syndrome, and traumatic brain injury. New-onset strabismus in adults may result from stroke, diabetes, or other illnesses that affect the nerves or muscles.
Correcting a Wandering Eye
Treatment for strabismus aims to correct eye alignment and ensure both eyes develop good vision, particularly in children. Non-surgical options include corrective lenses, which can sometimes fully resolve cases like accommodative esotropia by reducing focusing strain. Prism lenses are another non-surgical tool, designed to bend the light entering the eye to help the brain fuse two images into one, providing immediate relief from double vision.
Vision therapy, involving a structured program of eye exercises, is used to improve eye coordination. Exercises like “pencil push-ups” train the eyes to converge on a single close object, often helpful for intermittent outward turning.
Occlusion therapy, which involves patching the stronger eye or using atropine drops to temporarily blur it, treats associated amblyopia (“lazy eye”). This forces the brain to use the misaligned eye, stimulating vision development, though patching itself does not correct the alignment.
Surgical intervention is often recommended when non-surgical treatments are insufficient. The procedure involves adjusting the position or tension of the extraocular muscles to align the eyes correctly. A surgeon may perform a recession (moving a muscle attachment site back to weaken its pull) or a resection (removing a small section to shorten and tighten the muscle). Adults undergoing surgery may be candidates for adjustable sutures, which allow the surgeon to fine-tune the muscle position shortly after the operation. For many, surgery significantly improves alignment, cosmetic appearance, and can sometimes expand the visual field.