Clinical Analysis of Central Islands after LASIK

Kang, S W; Kim, W J

Abstract

This study was to analyze the central island after LASIK[laser in situkeratomileusis regarding its incidence, clinical characteristics and factors likely to be associated with its formation. LASIK was performed on 103 eyes of 61 patients using the Hansatome[Chiron co. USA] and SVS Apex plus[ver. 3.2.1] excimer laser implemented with anti-central island program. The mean of postoperative uncorrected visual acuity[UCVA] and of best corrected visual acuity[BCVA] were 0.12, and 0.06 in LogMAR scale respectively, and the mean refractive error was 0.07+/-0.76D[SE]. In topographic examination[Orbscan, Orbtek co. USA], the central island which was defined as an area of higher refractive power of more than 1.5D and more than 2.5mm in diameter, was observed in 12 eyes of 12 patients[11.7%]. The occurrence of central islands was related with UCVA and postoperative change of BCVA[student t-test, p<0.05], but not with preoperative refractive error, corneal thickness, age, sex and correction of astigmatism[student t-test, X2-test, p>0.05]. In conclusion there were sizable occurrences of central islands after LASIK as in photorefractive keratectomy despite the application of anti-central island pretreatment program. Therefore further studies are required on the central island after LASIK with respect to its impact on surgical result, clinical progress, and the measures to prevent its occurrence.