小切口超声乳化白内障摘出术后早期角膜屈光状态和中央角膜厚度对视力的影响

Influence of corneal astigmatism and central corneal thickness on vision following small-incision phacoemulsification

背景 小切口超声乳化白内障摘出联合人工晶状体（IOL）植入术是目前白内障治疗的主流术式,其术后视力的恢复受术中、术后并发症以及术后角膜屈光和中央角膜厚度（CCT）改变的影响,其中角膜屈光改变和CCT对视力波动的影响研究较少. 目的 分析小切口超声乳化白内障摘出术后早期患者的视力波动情况及其影响因素.方法 采用系列病例观察研究设计,选取2011年11月至2012年4月于复旦大学附属眼耳鼻喉科医院行2.6mm颞侧透明角膜切口超声乳化白内障摘出联合折叠型IOL植入术的年龄相关性白内障患者25例29眼,白内障手术均由同一医师完成.分别于术前1d,术后1、3、14d及术后1个月、2个月进行电脑验光和主觉验光,检查术眼裸眼视力（UCVA）和最佳矫正视力（BCVA）,用Pentacam眼前节分析系统测量CCT及角膜散光值,结果均采用矢量分析法.对术眼手术前后UCVA、BCVA、等效球镜度（SE）、角膜散光值和CCT进行比较,并分析UCVA和BCVA的影响因素. 结果 术眼术后1d平均UCVA（LogMAR）为0.52±0.06,2个月为0.64±0.07,差异有统计学意义（t=-3.051,P＜0.05）;术眼术后1d平均BCVA（LogMAR）为0.24±0.04,术后2个月为0.13±0.04,差异有统计学意义（t=-3.031,P＜0.05）.术眼术后1、14、60 d的SE差异有统计学意义（F=3.562,P=0.039）,术后1d的SE为（-1.74±0.28）D,术后14 d为（-1.99±0.27）D,差异有统计学意义（t=2.515,P＜0.05）;术眼术后2个月SE为（-1.69±0.24）D,明显低于术后14d的SE值,差异有统计学意义（=-2.987,P＜0.05）.术眼术前J0成分为（0.06±0.06）D,术后1d增加到（0.29±0.08）D,差异有统计学意义（t=-4.625,P＜0.01）;术后14 d J0成分为（0.38±0.07）D,明显高于术后1d值,差异亦有统计学意义（t=-7.858,P＜0.01）;术后2个月J0成分为（0.27±0.07）D,与术后14d比较差异有统计意义（t=-5.649,P＜0.01）.术眼手术前后CCT的差异有统计学意义（F=9.792,P＜0.001）.术眼术前平均CCT为（547.1±25.3） μm,术后ld为（599.4±56.9） μm,差异有统计学意义（t=-5.116,P＜0.01）,至术后14 d为（557.0±27.1）μm,明显低于术后ld值,差异有统计学意义（t=4.135,P＜0.01）,术后2个月时CCT为（551.0±25.9） μm,与术后14d时比较差异有统计学意义（t=2.082,P＜0.05）.术后UCVA仅与角膜J45相关,UCVA=0.513-1.183×C J45（F=16.724;t=-4.089,P=0.026）;BCVA仅与CCT相关,BCVA=-1.314＋0.003×CCT（F=22.322;t =4.725,P=0.018）. 结论 在无明显术中术后并发症的情况下,2.6mm颞侧透明角膜切口超声乳化白内障摘出联合IOL植入术术后早期术眼UCVA呈下降趋势,其波动主要受角膜散光改变的影响;而BCVA呈上升趋势,主要受CCT改变的影响.

Background Small incision cataract surgery combined with intraocular lens （IOL） implantation remains a popular way for cataract.However,some factors affect the postsurgical visual outcomes and lower the patients＆#39; satisfaction,including intraoperative and postoperative complications as well as corneal refractive and thickness changes.Objective This study was to evaluate the influence of corneal refractive and thickness changes on visual fluctuation after 2.6 mm temporal incision surgery for cataract.Methods A series cases-observational study was designed.Twenty-nine eyes of 25 age-related cataract patients received 2.6 mm temporal transparent incision phacoemulsification and IOL implantation from November,2011 through April,2012 in Eye ＆amp; ENT Hospital of Fudan University under the informed consent.The uncorrected visual acuity （UCVA）,best corrected visual acuity （BCVA）,automatic and subjective refraction were examined,and the central corneal thickness （CCT） and corneal vector astigmatism were measured using Pentacam analysis system before and after operation.The examination outcomes were compared among different time points,and the influencing factors of UCVA or BCVA were analyzed.Results The mean UCVA （LogMAR） was 0.52±0.06 in 1 day and 0.64±0.07 in 2 months after surgery,with a significant difference between them （t=-3.051,P〈0.05）.The mean BCVA （LogMAR） was 0.24±0.04 and 0.13± 0.04 in postoperative 1 day and 2 months,showing a significant difference between them （t =-3.031,P〈0.05）.Spherical equivalents （SE） were （-1.74±0.28） D,（-1.99±0.27） D and （-1.69±0.24） D in postoperative 1 day,14 days and 60 days,respectively,with a significant difference among the 3 time points （F =3.562,P =0.039）,and significant difference also was found between postoperative 1 day and 14 days （t =2.515,P〈0.05） or between postoperative 14 days and 60 days （t =-2.987,P 〈 0.05）.The preoperative J0 value was （0.06 ± 0.06） D,and postoperative J0 value was （0.29±0.08） D on the first day,which was significant higher than that in preoperation （t =-4.625,P〈0.01）.In addition,J0 value showed a significant difference between postoperative 1 day and 14 days （t=-7.858,P〈0.01） as well as between postoperative 14 days and 2 months （[0.38±0.07] D versus [0.27±0.07] D,t=-5.649,P〈0.01）.The mean CCT was （547.1±25.3） μm,（599.4±56.9） μm,（557.0±27.1） μm and （551.0 ± 25.9） μm before and 1 day,14 and 60 days after operation,with significant differences among the various time points （F =9.792,P 〈 0.001）,and significant differences also were seen in the CCT between preoperation and postoperative 1 day （t =-5.116,P〈0.01）,between postoperative 1 day and 14 days （t =4.135,P〈 0.01）,between postoperative 14 days and 60 days （t=2.082,P〈0.05）.UCVA=0.513-1.183×C J45（F=16.724;t=-4.089,P=0.026） and BCVA=-1.314＋0.003×CCT （F=22.322;t=4.725,P=0.018）.Conclusions The UCVA remains a downward trend,and BCVA sustains upward trend after 2.6 mm temporal transparent incision phacoemulsification combined with IOL implantation surgery.Postoperative UCVA is affected by corneal astigmatism change,while BCVA is influenced by CCT change.