Corneal ectatic disorders

Corneal ectatic disorders or corneal ectasia are a group of uncommon, noninflammatory, eye disorders characterised by bilateral thinning of the central, paracentral, or peripheral cornea.[1]

  • Keratoconus, a progressive, noninflammatory, bilateral, asymmetric disease, characterized by paraxial stromal thinning and weakening that leads to corneal surface distortion.[2]
  • Keratoglobus, a rare noninflammatory corneal thinning disorder, characterised by generalised thinning and globular protrusion of the cornea.[3]
  • Pellucid marginal degeneration, a bilateral, noninflammatory disorder, characterized by a peripheral band of thinning of the inferior cornea.[4]
  • Posterior keratoconus, a rare condition, usually congenital, which causes a nonprogressive thinning of the inner surface of the cornea, while the curvature of the anterior surface remains normal. Usually only a single eye is affected.
  • Post-LASIK ectasia, a complication of LASIK eye surgery.[5]
  • Terrien's marginal degeneration, a painless, noninflammatory, unilateral or asymmetrically bilateral, slowly progressive thinning of the peripheral corneal stroma.[6][7]

Diagnosis

Treatment

Treatment options include contact lenses and intrastromal corneal ring segments for correcting refractive errors caused by irregular corneal surface,[8][9] corneal collagen cross-linking to strengthen a weak and ectatic cornea,[10] or corneal transplant for advanced cases.

gollark: What if CODE GUESSING 17259815?
gollark: What I can easily do is construct a backdoor which nobody else can use, but I don't think that qualifies.
gollark: And practical hidden flaws are more like "if you encrypt 2^16 bytes with the same key it is possible to determine some of the plaintext with slightly higher probability" or known plaintext attacks and such, rather than "hahaha any message whatsoever can be decrypted".
gollark: I have some rough ideas but they'd probably be obvious to anyone competent.
gollark: I would, but I would have to actually know cryptography, which is nontrivial.

References
  1. "Corneal ectatic disorders (keratoconus and pellucid marginal degeneration)". AAO ONE Network. American Academy of Ophthalmology.
  2. Weissman, Barry A; Yeung, Karen K (2019-05-30). "Keratoconus". Medscape.
  3. Wallang, B S; Das, S (28 June 2013). "Keratoglobus". Eye. 27 (9): 1004–1012. doi:10.1038/eye.2013.130. PMC 3772364. PMID 23807384.
  4. Rasheed, Karim; Rabinowitz, Yaron (2018-12-24). "Pellucid Marginal Degeneration". Medscape.
  5. "Ectasia After LASIK". American Academy of Ophthalmology.
  6. "Terrien marginal degeneration". American Academy of Ophthalmology.
  7. "קרטוקונוס". Wednesday, 21 August 2019
  8. Marsack, Jason D.; Parker, Katrina E.; Applegate, Raymond A. (December 2008). "Performance of Wavefront-Guided Soft Lenses in Three Keratoconus Subjects". Optometry and Vision Science. 85 (12): E1172–E1178. doi:10.1097/OPX.0b013e31818e8eaa. PMC 2614306. PMID 19050464.
  9. Marsack, JD; Parker, KE; Niu, Y; Pesudovs, K; Applegate, RA (November 2007). "On-eye performance of custom wavefront-guided soft contact lenses in a habitual soft lens-wearing keratoconic patient". Journal of Refractive Surgery. 23 (9): 960–4. doi:10.3928/1081-597x-20071101-18. PMID 18041254.
  10. Avni-Zauberman, N; Rootman, DS (November 2014). "Cross-linking and intracorneal ring segments--review of the literature". Eye & Contact Lens. 40 (6): 365–70. doi:10.1097/icl.0000000000000091. PMID 25320956.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.