Megalocornea Clinical Presentation

  • Author: Thomas A Oetting, MD; Chief Editor: Hampton Roy Sr, MD   more...
 
Updated: May 21, 2010
 

History

  • Megalocornea is present from birth.
  • A family history of megalocornea may be present.
  • The mother may have slightly enlarged corneas.
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Physical

Findings of simple megalocornea

  • Usually bilateral
  • Usually good visual acuity
  • With-the-rule astigmatism common
  • Corneal diameter usually 13.0-16.5 mm
  • Corneal thickness normal and stroma clear; may have central mosaic dystrophy (see the image below)Central mosaic dystrophy sometimes noted in megaloCentral mosaic dystrophy sometimes noted in megalocornea.
  • Limbus sharply demarcated
  • Keratometry usually normal but may be steeper than normal
  • Anterior chamber depth increased
  • Lens-iris diaphragm positioned posteriorly
  • Vitreous length short
  • Intraocular pressure normal

Findings of anterior megalophthalmos

  • Megalocornea
  • Ciliary body band wider than the trabecular meshwork and scleral spur on gonioscopy
  • May have any of the following:
    • Iridodonesis
    • Iris stromal hypoplasia
    • Transillumination defects
    • Phacodonesis
    • Ectopia lentis
    • Cataracts
    • Krukenberg spindles
    • Posterior embryotoxon
    • Excessive mesenchymal tissue in the angle
    • Glaucoma (but not congenital glaucoma)

Findings of congenital glaucoma not found in megalocornea

  • Elevated intraocular pressure
  • Corneal edema and Haab striae
  • Optic disc cupping
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Causes

  • Megalocornea is inherited as an X-linked recessive trait (90% of cases).
  • The gene locus for X-linked megalocornea is in band Xq12-q26, most likely band Xq21-q23.
  • Autosomal dominant, autosomal recessive, and sporadic inheritance have been reported.
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Contributor Information and Disclosures
Author

Thomas A Oetting, MD  Professor, Residency Program Director, Department of Ophthalmology, University of Iowa Carver College of Medicine

Thomas A Oetting, MD is a member of the following medical societies: American Academy of Ophthalmology and American Society of Cataract and Refractive Surgery

Disclosure: Nothing to disclose.

Coauthor(s)

Mark A Hendrix, MD  Consulting Staff, Department of Ophthalmology, Suburban Hospital, Shady Grove Hospital

Mark A Hendrix, MD is a member of the following medical societies: American Academy of Ophthalmology and American Medical Association

Disclosure: Nothing to disclose.

Specialty Editor Board

Fernando H Murillo-Lopez, MD  Senior Surgeon, Unidad Privada de Oftalmologia CEMES

Fernando H Murillo-Lopez, MD is a member of the following medical societies: American Academy of Ophthalmology

Disclosure: Nothing to disclose.

Simon K Law, MD, PharmD  Assistant Professor of Ophthalmology, Jules Stein Eye Institute; Chief of Section of Ophthalmology Surgical Services, Department of Veterans Affairs Healthcare Center, West Los Angeles

Simon K Law, MD, PharmD is a member of the following medical societies: American Academy of Ophthalmology, American Glaucoma Society, and Association for Research in Vision and Ophthalmology

Disclosure: Nothing to disclose.

Christopher J Rapuano, MD  Professor, Department of Ophthalmology, Jefferson Medical College of Thomas Jefferson University; Co-Chairman of the Cornea Service, Co-Chairman of Refractive Surgery Department, Wills Eye Institute

Christopher J Rapuano, MD is a member of the following medical societies: American Academy of Ophthalmology, American Society of Cataract and Refractive Surgery, Contact Lens Association of Ophthalmologists, Cornea Society, Eye Bank Association of America, International Society of Refractive Surgery, and Pan-American Association of Ophthalmology

Disclosure: Allergan Honoraria Speaking and teaching; Allergan Consulting fee Consulting; Alcon Honoraria Speaking and teaching; Inspire Honoraria Speaking and teaching; RPS Ownership interest Other; Vistakon Honoraria Speaking and teaching; EyeGate Pharma Consulting; Inspire Consulting fee Consulting; Bausch & Lomb Honoraria Speaking and teaching

Lance L Brown, OD, MD  Ophthalmologist, Affiliated With Freeman Hospital and St John's Hospital, Regional Eye Center, Joplin, Missouri

Disclosure: Nothing to disclose.

Chief Editor

Hampton Roy Sr, MD  Associate Clinical Professor, Department of Ophthalmology, University of Arkansas for Medical Sciences

Hampton Roy Sr, MD is a member of the following medical societies: American Academy of Ophthalmology, American College of Surgeons, and Pan-American Association of Ophthalmology

Disclosure: Nothing to disclose.

References

  1. Saatci AO, Soylev M, Kavukcu S, Durak I, Saatci I, Memisoglu B. Bilateral megalocornea with unilateral lens subluxation. Ophthalmic Genet. Mar 1997;18(1):35-8. [Medline].

  2. Oetting TA, Newsom TH. Bilateral Artisan lens for aphakia and megalocornea: Long-term follow-up. J Cataract Refract Surg. Mar 2006;32(3):526-8. [Medline].

  3. Basti S, Koch DD. Secondary peripheral iris suture fixation of an acrylic IOL in megalocornea. J Cataract Refract Surg. Jan 2005;31(1):7; author reply 8. [Medline].

  4. Chang DF. Siepser slipknot for McCannel iris-suture fixation of subluxated intraocular lenses. J Cataract Refract Surg. Jun 2004;30(6):1170-6. [Medline].

  5. Kraft SP, Judisch GF, Grayson DM. Megalocornea: a clinical and echographic study of an autosomal dominant pedigree. J Pediatr Ophthalmol Strabismus. Sep-Oct 1984;21(5):190-3. [Medline].

  6. Mackey DA, Buttery RG, Wise GM, Denton MJ. Description of X-linked megalocornea with identification of the gene locus. Arch Ophthalmol. Jun 1991;109(6):829-33. [Medline].

  7. Maumenee IH. The cornea in connective tissue diseases. Ophthalmology. Oct 1978;85(10):1014-7. [Medline].

  8. Meire FM. Megalocornea. Clinical and genetic aspects. Doc Ophthalmol. 1994;87(1):1-121. [Medline].

  9. Meire FM, Bleeker-Wagemakers EM, Oehler M, Gal A, Delleman JW. X-linked megalocornea. Ocular findings and linkage analysis. Ophthalmic Paediatr Genet. Sep 1991;12(3):153-7. [Medline].

  10. Meire FM, Delleman JW. Biometry in X linked megalocornea: pathognomonic findings. Br J Ophthalmol. Oct 1994;78(10):781-5. [Medline].

  11. OMIM. Online Mendelian Inheritance in Man, OMIM(TM). McKusick-Nathans Institute for Genetic Medicine, Johns Hopkins University (Baltimore, MD) and National Center for Biotechnology Information, National Library of Medicine (Bethesda, MD), 2000. Available at: http://www.ncbi.nlm.gov/Omim/.

  12. Skuta GL, Sugar J, Ericson ES. Corneal endothelial cell measurements in megalocornea. Arch Ophthalmol. Jan 1983;101(1):51-3. [Medline].

  13. Srivastava AK, McMillan S, Jermak C, Shomaker M, Copeland-Yates SA, et al. Integrated STS/YAC physical, genetic, and transcript map of human Xq21.3 to q23/q24 (DXS1203-DXS1059). Genomics. Jun 1 1999;58(2):188-201. [Medline].

  14. Starck T, Hersh PS, Kenyon KR. Corneal dysgeneses, dystrophies, and degenerations. In: Principles and Practice of Ophthalmology. Vol 2. 2000:695-696.

  15. Wood WJ, Green WR, Marr WG. Megalocornea: A clinico-pathologic clinical case report. Md State Med J. Jul 1974;23(7):57-60. [Medline].

  16. Assia EI, Segev F, Michaeli A. Cataract surgery in megalocornea Comparison of 2 surgical approaches in a single patient. J Cataract Refract Surg. Dec 2009;35(12):2042-6. [Medline].

 
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Central mosaic dystrophy sometimes noted in megalocornea.
Megalocornea.
Megalocornea patient with Artisan lens.
B-scan ultrasound showing a large flat iris.
Aphakic megalocornea patient with 15 mm white to white.
 
 
 
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