Correlation between refractive and corneal topographic changes after photorefractive keratectomy for myopia.
OBJECTIVE
To compare videokeratographic and refractive data obtained before and after photorefractive keratectomy (PRK) for myopia.


METHODS
Seventy-four eyes underwent PRK for myopia ranging from -2.50 to -17.00 D (mean, -7.76 +/- 3.17 D). All patients had videokeratography with the EyeSys instrument before, and 1 and 6 months after PRK, and the changes in three corneal power measurements (center of the ablation, apex, and effective refractive power) were compared with refractive changes.


RESULTS
Changes obtained in the three corneal power measurements at 1 and 6 months were well correlated with manifest refraction (Pearson's coefficient ranged from 0.71 to 0.84).


CONCLUSIONS
Power measurements obtained with corneal topography, as described above, are a reliable and objective method for the evaluation and follow-up of PRK, provided addition of an approximate 25% correcting factor.
Rosa
N
N
Eye Department, Second University of Naples, Italy. nicrosa@tin.it
Cennamo
G
G
Rinaldi
M
M
D000328:Adult; D003315:Cornea / Q000503:physiopathology / Q000601:surgery*; D019781:Corneal Topography; D005260:Female; D006801:Humans; D054018:Lasers, Excimer; D008297:Male; D008875:Middle Aged; D009216:Myopia / Q000503:physiopathology / Q000601:surgery*; D018903:Photorefractive Keratectomy; D012029:Refraction, Ocular / Q000502:physiology*; D014792:Visual Acuity / Q000502:physiology