DSAEK手术植片厚度和大小对角膜内皮细胞密度的远期影响

Long-term influence of donor graft thickness and size on corneal endothelial cell density of Descemet stripping automated endothelial keratoplasty

目的探讨角膜后弹力层剥除联合自动角膜刀取材内皮移植术(DSAEK)供体中央植片厚度(CGT)和大小对角膜内皮细胞密度(ECD)的远期影响。方法采用系列病例观察研究,收集2013年1月至2017年12月因角膜内皮功能失代偿在北京大学第三医院眼科中心接受DSAEK手术并严格完成2年或以上随访的患者134例144眼。采用角膜内皮镜测量术前供体ECD;术后1、3、6、12和24个月,采用激光扫描共聚焦显微镜测量术后ECD,计算角膜内皮细胞丢失率;采用眼前节光相干断层扫描仪测量供体CGT。根据术后3个月供体CGT将患者分为薄植片组45眼、中等厚植片组66眼和厚植片组33眼,分别为供体CGT<100μm、≥100~<150μm和≥150μm。根据角膜环钻切割的供体植片大小将患者分为小植片组31眼和大植片组113眼,分别为供体植片直径≥7~<8 mm和≥8~<9 mm。比较手术后供体CGT变化及术后不同时间点角膜内皮细胞丢失率;分析术后24个月ECD与术前供体植片ECD、大小及CGT的相关性。结果术后1、3、6、12和24个月供体CGT分别为129.0(90.8,160.8)、115.5(93.0,146.0)、115.5(89.0,151.0)、112.5(94.3,146.8)和114.0(89.0,144.5)μm,总体比较差异有统计学意义(H=37.369,P<0.001),其中术后1个月供体CGT与术后3个月相比差异有统计学意义(P<0.001)。术后1、3、6、12、24个月,薄植片组、中等厚植片组和厚植片组以及大植片组、小植片组角膜内皮细胞丢失率比较差异均无统计学意义(均P>0.05)。Spearman相关性分析显示,术后24个月时ECD与术前供体植片ECD呈强正相关(r_(s)=0.783,P<0.001),与供体植片大小和CGT均无明显相关性(r_(s)=0.141,P=0.093;r_(s)=-0.044,P=0.600)。结论术前供体植片ECD越大,术后ECD越大;供体植片越薄、直径越大,DSAEK术后远期角膜内皮细胞丢失率越低。

Objective To explore the long-term influence of donor central graft thickness(CGT)and donor graft size on corneal endothelial cell density(ECD)after Descemet stripping automated endothelial keratoplasty(DSAEK).Methods An observational case series study was conducted.One hundred and forty-four eyes of 134 patients who underwent DSAEK in Peking University Third Hospital from January 2013 to December 2017 with at least 24-month follow-up were enrolled.Preoperative donor ECD was evaluated by specular microscopy,and ECD was determined by in vivo confocal microscopy at 1,3,6,12,and 24 months postoperatively.Donor CGT was measured by anterior segment optical coherence tomography.According to the 3-month postoperative donor CGT,the subjects were divided into thinner graft group(45 eyes with CGT<100μm),medium-thick graft group(66 eyes with CGT≥100-<150μm)and thicker graft group(33 eyes with CGT≥150μm).According to the donor trephination size,the subjects were divided into smaller graft group(31 eyes with trephination size≥7-<8 mm)and larger graft group(113 eyes with trephination size≥8-<9 mm).The changes of the donor CGT and corneal endothelial cell loss rate were compared at different time points after surgery.The relationships between 24-month postoperative ECD and donor ECD,donor graft size and donor CGT were analyzed.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of Peking University Third Hospital(No.IRB00006761-2008025).Written informed consent was obtained from each subject prior to any medical examination.Results The donor CGT was 129.0(90.8,160.8),115.5(93.0,146.0),115.5(89.0,151.0),112.5(94.3,146.8)and 114.0(89.0,144.5)μm at 1,3,6,12 and 24 months after surgery,showing a statistically significant difference(H=37.369,P<0.001).There was a statistically significant difference between 1-month and 3-month postoperative CGT(P<0.001).There was no statistically significant difference in the endothelial cell loss rate among the three different donor CGT groups and between the two different donor graft size groups at any postoperative time points(all at P>0.05).Spearman correlation analysis showed that the 24-month postoperative ECD was strongly positively correlated with the preoperative donor ECD(r s=0.783,P<0.001),which was not associated with donor graft size and donor CGT(r_(s)=0.141,P=0.093;r_(s)=-0.044,P=0.600).Conclusions Larger postoperative ECD is correlated with larger preoperative ECD of donor graft.Lower long-term corneal endothelial cell loss rate after DSAEK is associated with thinner and larger diameter of donor graft.