Toric laser in situ keratomileusis for myopic astigmatism using an ablatable mask.
BACKGROUND
To assess the results of toric laser in situ keratomileusis (LASIK) correction of myopic astigmatism.


METHODS
A prospective study was performed over a 20 week period for consecutive patients treated for myopic astigmatism. Spectacle-corrected visual acuity, uncorrected visual acuity, spectacle refraction, videokeratography, and complications were recorded. Vector analysis was performed by the ASSORT program.


RESULTS
Sixty-five eyes of 42 patients underwent toric LASIK with a Summit Technologies Apex Plus excimer laser. Mean preoperative spherical equivalent refraction at the spectacle plane was -6.24 +/- 2.42 D (range, -1.63 to -14.63 D) and mean pre-operative refractive cylinder magnitude was 1.99 +/- 1.35 D (range, 0.75 to 7.00 D); mean attempted refractive cylinder correction was 1.90 +/- 1.00 D. Six months after LASIK (43 eyes followed), mean spherical equivalent refraction at the spectacle plane was -0.40 +/- 0.55 D and 31 eyes (72.1%) were within +/- 0.50 D of emmetropia. At 6 months, mean refractive cylinder magnitude was 0.74 +/- 0.70 D, mean surgically induced astigmatism was 1.46 +/- 0.86 D, mean absolute angle of error was 10.33 degrees, mean astigmatic correction index was 0.93 +/- 0.36 D, and mean index of success was 0.46 +/- 0.39. Uncorrected visual acuity was 6/12 or better in 34 eyes (79.1%) and 6/6 in 15 eyes (35%); spectacle- corrected visual acuity was 6/9 or better in 41 eyes (95.35%). Six eyes (14.0%) lost 1 line of spectacle-corrected visual acuity at 6 months and one eye (2.3%) lost 2 lines. Ten eyes (23.3%) gained 1 line at 6 months.


CONCLUSIONS
Toric LASIK with an ablatable mask using the Summit Apex Plus excimer laser is a safe and relatively accurate procedure for the correction of myopic astigmatism.
Fraenkel
G E
GE
Sydney Refractive Surgery Centre, Chatswood, NSW, Australia.
Webber
S K
SK
Sutton
G L
GL
Lawless
M A
MA
Rogers
C M
CM
D000328:Adult; D000368:Aged; D001251:Astigmatism / Q000150:complications / Q000473:pathology / Q000601:surgery*; D003315:Cornea / Q000473:pathology / Q000601:surgery*; D019781:Corneal Topography; D016039:Corneal Transplantation / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053685:Laser Therapy / Q000295:instrumentation*; D008297:Male; D008875:Middle Aged; D009216:Myopia / Q000150:complications / Q000473:pathology / Q000601:surgery*; D011446:Prospective Studies; D012029:Refraction, Ocular; D015203:Reproducibility of Results; D016896:Treatment Outcome; D014792:Visual Acuity