Ophthalmology Book

Lens Disorders

  • Cataract Extraction

Vision Disorders

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Cataract Extraction

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  1. Definition
    1. Surgical removal of lens
  2. Indication: Visual Impairment secondary to Cataract
    1. Prevents Activities of Daily Living (ADL)
    2. Significantly interferes with patient's life-style
  3. Efficacy
    1. Patients achieving vision 20/40 or better: 90%
    2. Patients with significantly improved vision: 95%
    3. Preoperative exam can predict poorer outcome
  4. Preparation
    1. Preoperative exam
      1. Medical conditions stable
      2. No current infectious disease
      3. No current Skin Infections
    2. Topical antibiotic used preoperatively
      1. Cleanses the lids
  5. Procedure
    1. Outpatient 1 hour procedure under Local Anesthesia
    2. Techniques
      1. Extracapsular (95%)
        1. Lens nucleus removed through anterior lens capsule
          1. Phacoemulsification used on younger patients
            1. Soft lens fragmented with ultrasound
            2. Lens components aspirated
        2. Posterior lens capsule polished and left intact
        3. Causes less derangement of surrounding tissue
        4. Provides chassis for new lens implant
      2. Intracapsular
        1. Older technique, used up until the mid 1980's
        2. Entire lens and capsule removed
        3. Lens frozen to cryoextractor tip and removed
  6. Lens Replacement
    1. Background
      1. Surgical Aphakia (absent lens)
      2. With Cataract removed, vision blurred without lens
    2. Types
      1. Intraocular lens Implant (95%)
        1. Implanted at time of Cataract surgery
        2. Lens implant can be delayed years after surgery
      2. Contact Lenses
        1. Difficult to handle for many elderly
        2. Requires sufficient eye tearing
      3. Aphakic Spectacles (least desirable)
        1. Magnify Vision 33%
        2. Distort images
        3. Limits peripheral vision
        4. Not tolerable for single eye correction
          1. Due to magnification difference
  7. Postoperative follow-up
    1. Ophthalmology follow-up:
      1. 24 hours after surgery
      2. 2-4 days after surgery
      3. Periodic exams until lens prescribed at 2-3 months
      4. Urgently for change in eye appearance or sensation
    2. Precautions
      1. Avoid Eye Trauma
      2. Avoid Increased Intraocular Pressure
        1. Strenuous Physical Activity
        2. Bending
      3. Use eye-shields or glasses all the time
    3. Management
      1. Eye patch
        1. Worn continuously for first week after surgery
        2. Worn only at night After first week
      2. Activities
        1. After first week, normal activities performed
        2. Patient may drive after first week if vision ok
      3. Medications
        1. Topical antibiotic and steroid for first 3-4 weeks
      4. Suture
        1. Small enough (10-0 nylon) to not require removal
        2. Suture removed at 6-8 weeks if necessary
      5. Healing
        1. Completely healed by 3 months after surgery
        2. May obtain final Refraction at that time
  8. Complications (5% Incidence of major complication)
    1. Fulminant Endophthalmitis (0.1% Incidence)
      1. Infection inside eye occurs within first week
      2. Caused by Staphylococcus and Streptococcus
      3. Vision Loss can occur in 24 hours (0.02% Incidence)
    2. Glaucoma
      1. Occurs in first 4 days
    3. Hemorrhage
    4. Suture breakage
    5. Intraocular lens displacement
    6. Iritis
    7. Clouding of Posterior Capsule
      1. Occurs in up to 50% of patients
      2. Follows extracapsular extraction within several years
      3. Treated by Neodymium YAG laser
        1. Causes breakdown of posterior capsule

Cataract Extraction (C0007389)

Definition (MSH)The removal of a cataractous CRYSTALLINE LENS from the eye.
Definition (CSP)procedures performed on the eye, used in the removal of a cataractous lens.
ConceptsTherapeutic or Preventive Procedure (T061)
ICD913.19
MSHD002387
EnglishCataract Extraction, Cataract extractions, Cataract surgery, CE - Cataract extraction, Excision of cataract, Extraction of cataract, Surgical Cataract Removal
Spanishcirugia de cataratas, escision de una catarata, extraccion de una catarata, reseccion de catarata
Parent ConceptsOphthalmologic Surgical Procedures (C0038901), Surgical ocular refractive procedure (C1274010), Cataract Extraction (C0007389), Operation on lens (C0197672), Extraction of lens of eye (C0197689), Anterior chamber of eye and/or lens operations (C0395027), Duplicate concept (C1274013), Surgical extraction (C1293139)
SourcesAOD, CSP, MSH, MTH, MTHCH, MTHICD9, SCTSPA, SNOMEDCT
Derived from the NIH UMLS (Unified Medical Language System)



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