Accuracy and precision of LASIK flap thickness using the IntraLase femtosecond laser in 1000 consecutive cases

J Refract Surg. 2008 Oct;24(8):802-6. doi: 10.3928/1081597X-20081001-06.

Abstract

Purpose: To report the safety and flap thickness predictability of LASIK using the IntraLase femtosecond laser.

Method: A retrospective analysis of 1000 consecutive LASIK cases was performed to assess the rate of intra- and postoperative complications and loss of best spectacle-corrected visual acuity (BSCVA). A subset of 260 eyes was prospectively analyzed to assess flap thickness predictability using subtraction ultrasound on the day of surgery.

Results: No serious intra- or postoperative complications were noted. Three (0.3%) patients had epithelial defects that required a bandage contact lens. Four (0.4%) patients had slipped caps on day 1 that required repositioning. Two (0.2%) patients developed grade I diffuse lamellar keratitis. No patient developed epithelial ingrowth >1 mm from the flap edge, transient light sensitivity, or infection. No patient lost > or = 2 lines of BSCVA at 6 months postoperatively. With an attempted flap thickness of 105 microm with the 15-KHz laser, the mean flap thickness was 116.79 +/- 10.75 microm (range: 95 to 148 microm) (n = 119). In the 30-KHz group (n = 141), the target corneal flap thickness was 115 microm, with a mean flap thickness of 114.02 +/- 9.82 microm (range: 93 to 163 microm). Overall 87.3% of eyes were within +/- 20 microm of the intended result. Ninety-eight percent of caps created with the 30-KHz laser were within +/- 20 microm compared to 74.8% in the 15-KHz group.

Conclusions: LASIK surgery with the IntraLase femtosecond laser is safe and flap thickness is predictable.

MeSH terms

  • Humans
  • Intraoperative Complications
  • Keratomileusis, Laser In Situ / standards*
  • Lasers, Excimer / therapeutic use*
  • Myopia / surgery
  • Postoperative Complications
  • Prospective Studies
  • Reproducibility of Results
  • Retrospective Studies
  • Surgical Flaps*
  • Visual Acuity