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Monofixation syndrome

AI overview

Monofixation syndrome (MFS) is an eye condition defined by less-than-perfect binocular vision, characterized by a small angle deviation with suppression of the deviated eye and the presence of binocular peripheral fusion.

Key points
  • MFS is defined by a small angle deviation with suppression of the deviated eye and binocular peripheral fusion.
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    It is defined by a small angle deviation with suppression of the deviated eye and the presence of binocular peripheral fusion.
  • MFS implies peripheral fusion without central fusion.
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    MFS implies peripheral fusion without central fusion.
  • Subjects with MFS often have a large-angle latent deviation (phoria) in addition to the manifest small-angle deviation (tropia).
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    subjects with MFS often also have a large-angle latent deviation
  • Stereoacuity is often in the range of 3000 to 70 arcseconds, with a small central suppression scotoma of 2 to 5 degrees.
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    Their stereoacuity is often in the range of 3000 to 70 arcseconds , and a small central suppression scotoma of 2 to 5 deg.
  • MFS is a rare condition affecting only about 1% of the general population.
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    MFS is estimated to affect only 1% of the general population.
  • There are three distinguishable forms: primary constant, primary decompensating, and consecutive MFS.
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    There are three distinguishable forms of this condition: primary constant, primary decompensating and consecutive MFS.
  • Primary MFS is believed to result from a primary sensorial defect, predisposing to anomalous retinal correspondence.
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    primary MFS is a result of a primary sensorial defect, predisposing to anomalous retinal correspondence
Symptoms
  • Small-angle manifest deviation (tropia) with suppression of the deviated eye.
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    a small angle deviation with suppression of the deviated eye
  • Large-angle latent deviation (phoria).
    source quote
    subjects with MFS often also have a large-angle latent deviation
  • Reduced stereoacuity in the range of 3000 to 70 arcseconds.
    source quote
    Their stereoacuity is often in the range of 3000 to 70 arcseconds
  • Small central suppression scotoma of 2 to 5 degrees.
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    a small central suppression scotoma of 2 to 5 deg
Diagnosis
  • Diagnosis is based on identifying a small angle deviation with suppression of the deviated eye and the presence of binocular peripheral fusion.
    source quote
    It is defined by a small angle deviation with suppression of the deviated eye and the presence of binocular peripheral fusion.
  • Stereoacuity testing may reveal values in the range of 3000 to 70 arcseconds.
    source quote
    Their stereoacuity is often in the range of 3000 to 70 arcseconds
  • A small central suppression scotoma of 2 to 5 degrees may be identified.
    source quote
    a small central suppression scotoma of 2 to 5 deg
Treatment
  • Surgical alignment before 24 months of age is associated with MFS resulting in the vast majority of cases, while later alignment results in a minority of cases.
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    MFS to result in the vast majority of cases if surgical alignment is reached before the age of 24 months and only in a minority of cases if it is reached later.
Prognosis

MFS results in the vast majority of cases if surgical alignment is reached before 24 months of age, and only in a minority of cases if reached later.

AI-synthesized from the Wikipedia article “Monofixation syndrome”. Not medical advice. Verify source →
Monofixation syndrome
Other namesMicrotropia, microstrabismus
SpecialtyOphthalmology Optometry

Monofixation syndrome (MFS) (also: microtropia or microstrabismus) is an eye condition defined by less-than-perfect binocular vision.[1] It is defined by a small angle deviation with suppression of the deviated eye and the presence of binocular peripheral fusion.[2] That is, MFS implies peripheral fusion without central fusion.[citation needed]

Aside the manifest small-angle deviation ("tropia"), subjects with MFS often also have a large-angle latent deviation ("phoria"). Their stereoacuity is often in the range of 3000 to 70 arcseconds, and a small central suppression scotoma of 2 to 5 deg.[3]

A rare condition, MFS is estimated to affect only 1% of the general population. There are three distinguishable forms of this condition: primary constant, primary decompensating and consecutive MFS. It is believed that primary MFS is a result of a primary sensorial defect, predisposing to anomalous retinal correspondence.[4]

Secondary MFS is a frequent outcome of surgical treatment of congenital esotropia.[2] A study of 1981 showed MFS to result in the vast majority of cases if surgical alignment is reached before the age of 24 months and only in a minority of cases if it is reached later.[5]

MFS was first described by Marshall Parks.[3]

  1. Segar, Sharmila (2021-09-14). "Monofixation Syndrome: Background, Pathophysiology, Epidemiology". Medscape Reference. Retrieved 2024-08-08.
  2. 1 2 Guthrie ME, Wright KW (September 2001). "Congenital esotropia". Ophthalmol Clin North Am. 14 (3): 419–24, viii. doi:10.1016/S0896-1549(05)70239-X. PMID 11705141.
  3. 1 2 Kenneth Weston Wright; Peter H. Spiegel (January 2003). Pediatric Ophthalmology and Strabismus. Springer Science & Business Media. p. 174. ISBN 978-0-387-95478-3.
  4. Lang J (1983). "Microtropia". Int Ophthalmol. 6 (1): 33–6. doi:10.1007/BF00137371. PMID 6826290.
  5. M.R. Ing (1961). "Early surgical alignment for congenital esotropia". Transactions of the American Ophthalmological Society (79): 625–663. Cited according to: Myron Yanoff; Jay S. Duker; James J. Augsburger (2009). Ophthalmology. Elsevier Health Sciences. p. 1323. ISBN 978-0-323-04332-8.