Cataract Extraction

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. Technique: General
   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. Technique: 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. Precautions
   1. Alpha-1 antagonists (esp. Tamsulosin or Flomax) are associated with surgical complications
      1. Surgical procedure can be proactively modified for patients on alpha-1 antagonists
      2. Intraoperative floppy iris syndrome (sudden prolapse and Pupil constriction in surgery)
      3. Increases complication rate as much as 2.3 times with Tamsulosin
         1. Retinal Detachment
         2. Lost lens fragment
         3. Severe iris defects
      4. References
         1. Chang (2008) J Cataract Refract Surg 34(12): 2153-62
         2. Bell (2009) JAMA 301(19): 1991-6
8. Management: 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
9. 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