Strabismus

Strabismus
Other namesHeterotropia, crossed eyes, squint[1]
A person with exotropia, an outward deviated eye
Pronunciation
SpecialtyOphthalmology, optometry
SymptomsNonaligned eyes[2]
ComplicationsAmblyopia, double vision[3]
TypesEsotropia (eyes crossed); exotropia (eyes diverge); hypertropia (eyes vertically misaligned)[3]
CausesMuscle dysfunction, farsightedness, problems in the brain, trauma, infections[3]
Risk factorsPremature birth, cerebral palsy, family history[3]
Diagnostic methodObserving light reflected from the pupil[3]
Differential diagnosisCranial nerve disease,[3] convergence insufficiency
TreatmentGlasses, surgery[3]
Frequency~2% (children)[3]

Strabismus is a vision disorder in which the eyes do not properly align with each other when looking at an object.[2] The eye that is pointed at an object can alternate.[3] The condition may be present occasionally or constantly.[3] If present during a large part of childhood, it may result in amblyopia, or lazy eyes, and loss of depth perception.[3] If onset is during adulthood, it is more likely to result in double vision.[3]

Strabismus can occur due to muscle dysfunction (e.g., myasthenia gravis[4][5]), farsightedness, problems in the brain, trauma, or infections.[3] Risk factors include premature birth, cerebral palsy, and a family history of the condition.[3] Types include esotropia, where the eyes are crossed ("cross eyed"); exotropia, where the eyes diverge ("lazy eyed" or "wall eyed"); and hypertropia or hypotropia where they are vertically misaligned.[3] They can also be classified by whether the problem is present in all directions a person looks (comitant) or varies by direction (incomitant).[3] Diagnosis may be made by observing the light reflecting from the person's eyes and finding that it is not centered on the pupil.[3] This is known as the Hirschberg reflex. Another condition that produces similar symptoms is a cranial nerve disease.[3]

Treatment depends on the type of strabismus and the underlying cause.[3] This may include the use of glasses and possibly surgery.[3] Some types benefit from early surgery.[3] Strabismus occurs in about 2% of children.[3] The term comes from the Ancient Greek word στραβισμός (strabismós), meaning 'a squinting'.[6] Other terms for the condition include "squint" and "cast of the eye".[7][8][9]

  1. ^ a b "Strabismus noun - Definition, pictures, pronunciation and usage notes | Oxford Advanced Learner's Dictionary". www.oxfordlearnersdictionaries.com. Archived from the original on August 1, 2017. Retrieved August 1, 2017.
  2. ^ a b "Visual Processing: Strabismus". National Eye Institute. National Institutes of Health. June 16, 2010. Archived from the original on October 5, 2016. Retrieved October 2, 2016.
  3. ^ a b c d e f g h i j k l m n o p q r s t u v Gunton KB, Wasserman BN, DeBenedictis C (September 2015). "Strabismus". Primary Care. 42 (3): 393–407. doi:10.1016/j.pop.2015.05.006. PMID 26319345.
  4. ^ Merino Sanz P, Del Cerro Pérez I, Alan Peinado G, Gómez de Liaño Sánchez P (March 2019). "Causes and surgical treatment of diplopia and strabismus secondary to myasthenia gravis". Archivos de la Sociedad Espanola de Oftalmologia. 94 (3): 107–113. doi:10.1016/j.oftal.2018.11.007. PMID 30580990.
  5. ^ Maeda M, Shimomura H, Tokunaga S, Taniguchi N, Lee T, Takeshima Y (May 2024). "Clinical Characteristics and Treatment of Juvenile Myasthenia Gravis-A Single-Center Experience". Children. 11 (5): 572. doi:10.3390/children11050572. PMC 11120409. PMID 38790567.
  6. ^ Harper DR. "strabismus (n.)". Online Etymology Dictionary. Archived from the original on December 12, 2016. Retrieved October 2, 2016.
  7. ^ Brown L (1993). The New shorter Oxford English dictionary on historical principles. Oxford: Clarendon. pp. Strabismus. ISBN 978-0-19-861271-1.
  8. ^ "strabismus". English: Oxford Living Dictionaries. Oxford University Press. 2016. Archived from the original on April 21, 2016. Retrieved April 6, 2016.
  9. ^ "the definition of squint". Dictionary.com. Retrieved July 20, 2016.