Related articles: Strabismus
Definition
Strabismus is a misalignment of the eyes that causes a deviation of the gaze. This convergence defect of the visual axes is due mostly to refraction errors (such as myopia, hyperopia and astigmatism) or to a lack of coordination between the eye muscles. Such situations prevent the gaze of each eye from orienting on the same objective, hindering correct binocular vision and negatively influencing depth perception.
Some children are born with a congenital strabismus, while others develop the disorder later (acquired strabismus). Rare causes of strabismus include retinoblastoma, head trauma and some neurological conditions (eg cerebral palsy, spina bifida, viral infections etc.).
Most common symptoms and signs *
- Eye fatigue
- Neck pain
- Headache
- Nystagmus
- Misaligned eyes
- Reduced vision
- Double vision
- Blurred vision
Further indications
The most obvious sign of strabismus is the uncoordinated movement of the eyes (in practice, they look in different directions). Very often, one eye looks straight ahead, while the other eye is diverted inward (convergent strabismus) or the outside (divergent strabismus), upward or downward (vertical strabismus). In children the inclination of the head or the raising of the chin is frequent to compensate for the difficulty of the brain to merge the images coming from the two misaligned eyes and thus allow a correct binocular vision. In adults, eyestrain, headache, stiff neck and double or blurred vision may occur.
If left untreated, strabismus can lead to reduced vision due to amblyopia (cortical suppression of the image perceived by the deviated eye to avoid confusion). Further consequences of the misalignment of the eyes in the child are the reduction of motor skills and a delay in development (as in walking and speaking).
Strabismus can be diagnosed during a routine eye exam, including observation of the corneal light reflex and assessment of visual acuity. Treatment may include correction of visual disturbances with spectacles and bandages, alignment with corrective lenses, use of topical myotic agents (to facilitate accommodation) and surgery.
