ABSTRACT
Background Implantation of phakic posterior chamber intraocular corrective lens(ICL)is a new choice for correction of high myopia.Different from laser assisted in situ keratomileusis,implantation of phakic posterior chamber ICL will allow the good imaging quality because it remaines the matched relationship between cornea and lens.But its visual quality after operation is concerned by patient and ophthalmologists.ObjectiveThis study was to observe the effectiveness of implantation of posterior chamber phakic ICL on visual quality in patients with high myopia.Methods Eighty-four high myopia eyes of 42 patients accepted implantation of posterior chamber phakic ICL and follow-up of 6-month duration.The visual acuity,refractive status,wavefront,contrast sensitivity and accommodation were examined and compared before and after surgery.This clinical study complied with Declaration of Helsinki.The written informed consent was obtained from each patient before operation.Results A prospective observational trial design was used.The uncorrected visual acuity and best corrected visual acuity after operation were better than preoperative ones in all of the patients.The eye numbers of ＞ 0.3 were increased after operation in comparison with before operation with a stable result among 1 day,1 month and 6 months after surgery (x2 =10.70,P＞0.05).Spherical equivalent refraction was(-15.38 ± 1.03)D before surgery and(+0.55 ±0.06)at 1 day,(-1.22±0.09)D at 1 month and(-0.68 ± 0.06)D after 6 months,showing a significant difference among them(F=16 559.90,P＜0.05).Total aberrations and higher-order aberrations were 11.00±0.25 and 0.43 ±0.05 before surgery,the wavefront aberrations were 2.21 ± 0.56 and 0.47±0.04 at 6 months after surgery with significant difference(t =1.65,P =0.10).Each spatial frequency contrast sensitivity and glare sensitivity on photopic and seotopie conditions in postoperation were higher compared with the preoperative(P＜0.05).The accommodation in 1 month and 6 months after surgery was greater than that of preoperative in the patients ＜-16 D(preoperation:2.75 ± 1.20 ; postoperation 1 month:5.75 ± 1.44,postoperation 6 months:6.00 ± 1.52)(P＜ 0.05),however,in the ＞-16 D group,no considerably change in accommodation was seen after surgery(F=1597.70,P＜0.05).No significant difference was found in accommodation between before and after surgery in ＞-16 D group(F=2.67,P＞0.05).Conclusions Visual quality of high myopia is obviously improved after implantation of posterior chamber phakic ICL,but its long-term outcome is need to further study.
ABSTRACT
Background High myopia can be corrected using laser therapy and intraocular lens(IOL)implantation.IOL implantation is more suitable than laser therapy for high myopia if the patients suffer from thinner cornea.Objective This clinical trail was to assess and compare the visual quality following phakic iris-claw intraocular lens (IOL) and implantable contact lens(ICL) implantation for high myopia.MethodsIris-claw phakic intraocular lens was implanted in 17 eyes of 10 patients with high myopia,and age-,refractive-matched 17 eyes of 9 patients were in implantable contact lens (ICL) implantation group.Uncorrected visual acuity,best correct visual acuity,contrast sensitivity under the 3,6,12 and 18 c/d spatial frequencies,wave-front aberrations,including RMS3,RMS4 and RMSh,were examined in 6 months after operation.Written informed consent was obtained from each patient before surgery.Results There were no significant difference in uncorrected visual acuity,best correct visual acuity between two groups(t=0.489,P>0.05;t=0.853,P>0.05).Non-glare CS under the 3 c/d,6 c/d,12 c/d and 18 c/d spatial frequencies were insignificantly different between two groups ( t = 0. 906, P > 0.05 ; t = 0. 103, P > 0. 05 ; t =0. 694 ,P>0. 05 ; t = 1. 583, P>0. 05), and the similar outcomes were found in glare CS ( t = 0. 323, P>0.05, t =0.041 ,P>0. 05, t = 0.024, P>0. 05; t = 0. 363, P>0.05) in postoperative 6 months. RMS3 and RMSh were significantly elevated in PIOL group compared with ICL group ( t = 11.40, P0. 05). Conclusion Both PIOL and ICL implantation for high myopia can achieve an equal visual acuity. But clinical outcomes of ICL implantation is much better than PIOL group. A long-term effect should be observed for the further evaluation.