Corneal Clarity Measurements In Patients With Myopia Undergoing Laser Assisted In Situ Keratomileusis And Laser Assisted Sub-Epithelial Keratectomy

PurposeTo compare the preoperative and postoperative corneal densitometry of patients undergoing Laser Assisted in Situ Keratomileusis (LASIK) and Laser Assisted Sub-epithelial Keratectomy (LASAK) and to determine how result differed between the 2 types of surgery.MethodsA retrospective and comparative study was performed at Manchester Royal Eye Hospital,UK. Preoperative and postoperative corneal densitometry data were collected from the Oculus Pentacam. The data were taken at 3 corneal depths (anterior,centre and posterior) and at 3 corneal annulus ring diameter (0-2 mm, 2-6 mm and 6-10 mm). Postoperative data were collected at the time 6 weeks, 3 and 6 months post treatment.Quality of vision pre and post-surgery was determined by BCVA.ResultsData of 60 eyes from 16 LASIK and 14 LASEK patients were collected with a mean age of 37.06 ± 10.0 and 37.7 ± 6.6 respectively. There was statistically significant increase of corneal densitometry in all concentric zones in all corneal layers after 6 weeks in the LASIK treatment group (p u003c 0.05). There was a statistically significant increase in densitometry after LASEK but only in the central and posterior layers at all concentric zones (p u003c 0.05). Pre and Postoperative BCVA did not significantly differ after LASIK but found statistically difference at 6 weeks and 3 months in post LASEK (p u003c 0.05).BCVA post treatment was significantly different between groups at 6 weeks (p u003c 0.0001) and 3 months (p = 0.001).ConclusionsCorneal wound healing plays an important role in determining corneal transparency and may be responsible for an increase in corneal haze following refractive surgery.This response differs based on the type of procedure used shown by the increased haze in the anterior layer of the LASIK group which corresponds to the region where the flap was cut which will lead to increased would healing and inflammation.