Exophoria

Last updated
Exophoria
Specialty Ophthalmology

Exophoria is a form of heterophoria in which there is a tendency of the eyes to deviate outward. [1] During examination, when the eyes are dissociated, the visual axes will appear to diverge away from one another. [2]

Contents

The axis deviation in exophoria is usually mild compared with that of exotropia.

Cause

Exophoria can be caused by several factors, which include:

These can be due to nerve, muscle, or congenital problems, or due to mechanical anomalies. Unlike exotropia, fusion is possible in this condition, causing diplopia to be uncommon.

Diagnosis

Prevalence

Exophoria is common in infancy and childhood, and increases with age. [3] [ clarification needed ]

References

  1. Allen, Edmund Turney (1899). The science of higher prisms. Harvard University: G. K. Hazlitt 6 Co., printer. p. 39. ISBN   978-1-02-235217-9.{{cite book}}: ISBN / Date incompatibility (help)
  2. Grosvenor, Theodore (2007). Primary Care Optometry 5th Ed. Butterworth-Heinemann. p. 224. ISBN   978-0-7506-7575-8.{{cite book}}: CS1 maint: location missing publisher (link)
  3. Freier BE, Pickwell LD (1983). "Physiological exophoria". Ophthalmic and Physiological Optics. 3 (3): 267–272. doi:10.1111/j.1475-1313.1983.tb00613.x. PMID   6646761. S2CID   11180397.