title: Erbium:YAG laser cataract removal: role of fiber-optic delivery system.
abstract: OBJECTIVE
  To review the properties of energy delivery systems and to evaluate the efficiency of zirconium-fluoride-based and sapphire fibers delivering erbium:YAG (Er:YAG) laser energy in a clinical laser cataract surgery system.
  
  
  METHODS
  Department of Ophthalmology, Medical College of Virginia Campus of Virginia Commonwealth University, and Veterans Affairs Medical Center, Richmond, Virginia, USA.
  
  
  METHODS
  Thirty-two patients had Er:YAG laser cataract extraction. Preoperative visual acuity ranged between finger counting and 20/40 secondary to cataract. The endothelial cell count was measured preoperatively and 6 weeks after surgery. A zirconium-fluoride-based fiber was used in 23 patients and a sapphire fiber in 9 patients.
  
  
  RESULTS
  Of the patients examined after 3 months (n = 31), 90.3% (n = 28) had a visual acuity of 20/30 or better and 9.7% (n = 3), of 20/40 or 20/50. Mean endothelial cell loss at 6 weeks was 7.6% +/- 12.8 (SD). Posterior capsule rupture with vitreous loss occurred in 3 cases; 1 was attributed to laser damage to the capsule. Conversion to ultrasound phacoemulsification was required in 13 cases. Suitable fiber materials for Er:YAG laser delivery are sapphire, zirconium fluoride, silica, and germanium oxide. Toxicity of the latter is under investigation.
  
  
  CONCLUSIONS
  The Er:YAG laser emulsified the lens nucleus safely and effectively. These early results include a higher than acceptable posterior capsule rupture rate and reflect the surgeon's learning curve with a new technology. Effective power delivery can be achieved with sapphire- and zirconium-fluoride-based fiber optics through a silica tip. The optimal energy delivery system has not been determined.
authors: Medical College of Virginia, Virginia Commonwealth University, Richmond, USA.
authors: C C
authors: CC
authors: Neubaur
authors: G
authors: G
authors: Stevens
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002387:Cataract Extraction / Q000379:methods*; D005336:Fiber Optic Technology; D005500:Follow-Up Studies; D006801:Humans; D053685:Laser Therapy / Q000379:methods*; D007907:Lens Nucleus, Crystalline / Q000601:surgery*; D008875:Middle Aged; D055100:Optical Fibers; D011183:Postoperative Complications; D016896:Treatment Outcome; D014792:Visual Acuity