Strabismus
Strabismus Information
A disorder of the eye in which optic axes cannot be directed to the same object. This disorder is present in about 4% of children. The squinting eye always deviates to the same extent when the eyes are carried in different directions: unilateral when the same eye always deviates; alternating when either deviates, the other being fixed; constant when the squint remains permanent; periodic when the eyes are occasionally free from it. Strabismus can result from reduced visual acuity, unequal ocular muscle tone, or an oculomotor nerve lesion.
SYN: heterotropia; squint.
Strabismus types:
- accommodative strabismus: Strabismus due to disorder of ocular accommodation. SYN: bilateral strabismus.
- alternating strabismus: Strabismus affecting either eye alternately.
- bilateral strabismus: Accommodative strabismus.
- concomitant strabismus: Strabismus in which both eyes move freely but retain an unnatural relationship to each other.
- convergent strabismus: Strabismus in which the deviating eye turns inward.
- divergent strabismus: Strabismus in which the deviating eye turns outward.
- horizontal strabismus: Strabismus in which the deviation of the visual axis is in the horizontal plane.
- intermittent strabismus: Strabismus recurring at intervals.
- monocular strabismus: Strabismus in which the same eye habitually deviates.
- monolateral strabismus: Strabismus with the squinting eye always the same.
- nonconcomitant strabismus: Strabismus of an eye that varies in degree with the change in direction in which the eye moves.
- paralytic strabismus: Strabismus due to paralysis of one of the extraocular muscles.
- spastic strabismus: Strabismus due to contraction of an ocular muscle.
- vertical strabismus: Strabismus in which the eye turns upward.
