Toric人工晶状体术后残余散光及手术源性散光（SIA）的临床观察

目的　观察Acrysof Toric人工晶状体（intraocular lens，IOL）植入术后的残余散光及手术源性散光（surgically induced astigmatism，SIA）。方法　回顾分析2016年2月至2017年6月行白内障超声乳化吸出联合Acrysof Toric IOL植入的患者52例（62眼），于术前及术后1个月观察患者的裸眼视力、最佳矫正视力、综合验光、角膜曲率等，并计算出个体SIA、平均数SIA和centroid SIA。结果　术后目标残余散光为0.02~0.32（0.17±0.15）D，术后实际残余散光为0~1.50（0.49±0.37）D，差异有统计学意义 （P＜0.05）。术前角膜散光值为0.93~3.70（1.94±0.75）D，术后角膜散光值为0.68~3.80（1.95±0.80）D。术后个体SIA为0.08~1.39（0.44±0.25）D，平均数SIA为0.44 D，centroid SIA为0.12 D@126°。结论　利用Barrett Toric公式及centroid SIA计算Toric IOL度数精确及稳定，但术后仍残留一定度数残余散光，SIA仍需进一步优化。

Clinical observation of residual astigmatism and surgically induced astigmatism (SIA) after Toric intraocular lens implantation

Objective　To investigate the residual astigmatism and surgically induced astigmatism (SIA) after implantation of Acrysof Toric intraocular lens (IOL).Methods　Totally 52 patients (62 eyes) who underwent phacoemulsification with Acrysof Toric IOL implantation from February 2016 to June 2017 were retrospectively reviewed.Observation of the variables including the uncorrected visual acuity，best corrected visual acuity，refraction，corneal curvature was performed，and individual SIA，mean SIA plus centroid SIA were calculated before surgery and one month after surgery.Results　There was significant difference between postoperative anticipated astigmatism and postoperative actual astigmatism ［(0.17± 0.15)D vs.(0.492 ±0.37)D］(P＜0.05).Preoperative corneal astigmatism was (1.94±0.75)D，ranging from 0.93 D to 3.70 D，and postoperative corneal astigmatism was (1.95±0.80)D，ranging from 0.68 D to 3.80 D.The individual SIA was 0.08-1.39 (0.44±0.25)D，the mean SIA of 0.44 D，and centroid SIA of 0.12 D @126°.Conclusion　It is precise and stable for Barrett Toric formula and centroid SIA to calculate the degree of Toric IOL，but there is still residual astigmatism after IOL implantation，so further optimization of SIA is still needed.