术前配戴软性角膜接触镜对LASIK术后高阶像差的影响

目的探讨术前配戴软性角膜接触镜对波前引导和传统准分子激光原位角膜磨镶术(LASIK)术后高阶像差的影响。方法采用前瞻性随机双盲比较性研究,将拟行LASIK的青壮年近视患者48名(96眼),其中,术前配戴软性角膜接触镜者26名(52眼),随机分为波前引导组和传统组,分别检查术前、术后不同时间的视力、对比敏感度和高阶像差,并比较术前戴角膜接触镜组(contactlens,C组)与未戴组(non-contactlens,N组)术后高阶像差变化。结果无论是传统组还是波前引导组术后不同时间的裸眼视力(UCVA)、最佳矫正视力(BSCVA)、安全指数、有效指数和对比敏感度增加倍率等方面C组与N组均无显著差异(P>0.05)。传统组和波前引导组术后总高阶像差和各高阶像差RMS值(RMSh和RMS3～6值)均较术前增加,平均增加约1倍。传统组中术后RMSh和RMS3～6值增加倍率和下降比例C组与N组无显著差异,术后6个月时RMSh值增加倍率分别为1.28倍、1.17倍。引导组中术后RMSh、RMS3～5值增加倍率C组均明显高于N组(P<0.05),术后6个月时RMSh值增加倍率分别为1.58倍、0.77倍(P<0.05),N组术后不同时间RMSh、RMS3～5值下降比例均高于C组。术后6个月时,RMSh值下降比例C组与N组分别为9.1%和22.7%。结论术前配戴软性角膜接触镜影响波前引导LASIK对高阶像差的矫正,而对传统LASIK术后高阶像差影响不明显。术前配戴软性角膜接触镜者行波前引导LASIK应慎重。

Effects of preoperative soft contact lens wear on higher-order aberrations after laser in situ keratomileusis

Objective To evaluate the effects of preoperative soft contact lens(SCLs) wear on higher-order aberrations(HOAs) after wavefront-guided and standard laser in situ keratomileusis(LASIK) .MethodsThis was a prospective randomized double-masked comparative study comprised 96 eyes of 48 young patientswho were scheduled for LASIK,including 52 eyes of 26 patients with soft contact lens wear.The patients weredivided into standard ablation group(group S) and wavefront-guided ablation group(group A) randomly.Pre-operative and postoperative examinations included uncorrected visual acuity(UCVA) ,best spectacle-correctedvisual acuity(BSCVA) ,contrast sensitivity and HOAs.The values of root-mean-square(RMS) of HOAs,in-cluding higher-order(RMSh) and the third-to the sixth-order(RMS3 to RMS6) ,were compared between thegroup of contact lens wearers(subgroup C) and non-contact lens wearers(subgroup N) after operation.ResultsNeither standard ablation group nor wavefront-guided ablation group had significant difference between sub-group N and subgroup C in UCVA,BSCVA,contrast sensitivity,safety index or efficacy index.The values ofRMSh and RMS3 to RMS6 increased by a mean factor of one in both standard and wavefront-guided ablationgroups after operation.There was no significant difference in the increase factor and decrease ratio of postoperativevalues of RMSh and RMS3 to RMS6 between subgroup C and subgroup N in standard ablation group,with anincrease factor of 1.28 and 1.17 of RMSh at 6 months postoperatively,respectively.However,in wavefront-guidedablation group,the postoperative values of RMS3 to RMS5 and RMSh and the decreased ratio of RMS HOAsvalue were higher in subgroup C than in subgroup N significantly.At 6-month interval,the values of RMShincreased 1.58 and 0.77 fold and the decreased ratio of the RMSh value were 9.1% and 22.7% in subgroup C andN,respectively.Conclusions The efficacy of HOAs correction was affected significantly by the contact lenswear preoperatively in wavefont-guided ablation group but no mild effects in standard ablation group.The patientswith contact lens wear preoperatively should think discretion to attempt wavefront-guided LASIK.