Preliminary Analysis About The Clinical Effect Of Wavefront-guided Laser In Situ Keratomileusis For Myopia

Objectives:To observe the outcome of objective indicators and subjective vision quality questionnaire of wavefront-guided laser in situ keratomileusis(LASIK) and compared with conventional LASIK, to study the effect of wavefront-guided laser in situ keratomileusis for myopic.Methods:40 eyes of 21 patients with myopic who underwent wavefront-guided LASIK from Jul of 2009 to Feb of 2010 were selected continuously as trial group and 31 eyes of 16 patients with myopic who accept conventional LASIK during the same period were selected continuously as control group. The postoperative follow-up lasted for one year. Visual acuity, refraction and high-order aberrations(HOAs) were examined before and after operation. A subjective vision quality questionnaire was administered after operation. The outcomes between two groups were compared.Results:1. One month after operation, uncorrected visual acuity (UCVA) of all eyes were higher than 1.0; After follow-up, UCVA of all eyes were higher than 0.8; UCVA achieved 1.0 or better in 97.5% of eyes in wavefront group and 96.8% in control group; UCVA achieved 1.5 or better in 35.0% of eyes in wavefront group and 16.1% in control group; A total of 37.5% of eyes exceeded the preoperative best corrected visual acuity(BCVA) in wavefront group and only 19.4% in control group, but the difference was not significant (P>0.05).2. After the operation, the difference of the mean spherical equivalent between two groups was not significant (P>0.05). The refractive regression is slightly over time. After follow-up, the eyes with postoperative refractions within (+1.0D--1.0D) and within (+0.5D--0.5D) accounted for 75.0% and 95.0% in wavefront group, and 77.4% and 93.5% in control group, respectively, but there was no significant difference in postoperative refractions between two groups(P＞0.05).3. After the operation, total HO A, coma and spherical values were increased in two groups (P<0.05). The values were reduced slightly over time. There were no significant differences in total HOA, coma and spherical values preoperative between two groups (P>0.05), but the values postoperative were lower in wavefront group than in control group(P<0.05). The increases of total HOA, coma and spherical values in wavefront group were less than the control group (P＜0.05). 4. The postoperative subjective visual quality questionnaire about the visual acuity assessment, there was no significant difference between the two groups during the day and dusk (P>0.05), the wave-front group was better than the control group in the night vision and night driving vision (P<0.05), the change of the visual assessment was not significant under various conditions (P>0.05); about the visual symptoms, the glare in wavefront group was less than the control group (P<0.05), there was no significant difference between the two groups in the halos, double images and night driving difficulties (P>0.05), the halos were significantly reduced in two groups (P<0.05).Conclusions:Both wavefront-guided LASIK and conventional LASIK achieved good results in UCVA. Postoperative refractions were stable and predictability was good in both groups. Total HOA, coma and spherical values were increased in two groups, and the values were reduced slightly over time. Compared with conventional LASIK, wavefront-guided LASIK was more efficient to reduce the HOA and the glare after operation, so as to improve the night vision quality.