Ophthalmology Book

Vision Disorders

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Refractive Corneal SurgeryAka: Refractive Surgery, Laser Thermal Keratoplasty, Intrastromal corneal ring, Intacs, Phakic Intraocular Lens

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  1. See Also
    1. Refractive Error
  2. Indications
    1. Refractive Error Correction
  3. Background: Refractive Surgery reshapes Cornea
    1. Myopia (Near-sightedness)
      1. Light rays focus in front of Cornea
      2. Surgery flattens Cornea to focus light further back
    2. Hyperopia (Far-sightedness)
      1. Light rays focus behind Cornea
      2. Surgery steepens Cornea to focus light closer
    3. Astigmatism
      1. Cornea is non-spherical with uneven surface
      2. Surgery evens out Cornea, directs light at retina
  4. Techniques
    1. Laser In-Situ Keratomileusis (LASIK)
    2. Photorefractive Keratectomy (PRK)
      1. Replaced by LASIK
    3. Radial Keratotomy (RK)
      1. Replaced by LASIK
    4. Laser Thermal Keratoplasty (LTK)
      1. YAG laser mediated radial spot placement
      2. Heats Cornea and shrinks stromal collagen
      3. Modifies anterior Corneal curvature
      4. Corrects presbyopic patient with <4 D Refraction
    5. Intrastromal Corneal ring (ICR or Intacs)
      1. Polymethylmethacrylate (PMMA) ring implanted
      2. Flattens central Cornea
      3. Corrects low Myopia (<3 D)
      4. Surgery easily adjustable
      5. No risk of central Corneal scarring
    6. Phakic Intraocular Lens
      1. Plastic intraocular lens
      2. Placed anterior to natural crystalline lens
      3. Corrects high Myopia and Hyperopia
  5. References
    1. Bower (2001) Am Fam Physician 64(7):1183
    2. Sanders (1998) J {a 6313} Refract Surg 24:607
    3. Schanzlin (1997) Ophthalmology 104:1067
    4. (1999) Med Lett Drugs Ther 41(1068):121

Surgical ocular refractive procedure (C1274010)

Definition (MSH)Surgical procedures employed to correct REFRACTIVE ERRORS such as MYOPIA; HYPEROPIA; or ASTIGMATISM. These may involve altering the curvature of the CORNEA; removal or replacement of the CRYSTALLINE LENS; or modification of the SCLERA to change the axial length of the eye.
ConceptsTherapeutic or Preventive Procedure (T061)
EnglishRefractive Surgeries, Refractive Surgery, Refractive Surgical Procedure, Refractive Surgical Procedures, Surgical ocular refraction procedure, Surgical ocular refractive procedure
Spanishcirugía refractaria, cirugía refractiva, cirugia refractaria, cirugia refractiva, procedimiento de refracción ocular quirúrgica, procedimiento de refraccion ocular quirurgica
CreditsDerived from the NIH UMLS (Unified Medical Language System)



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