浅前房对人工晶状体计算公式预测屈光误差的影响

The effect of shallow chamber depth on the prediction error of different intraocular lens calculation formulas

目的分析浅前房对不同人工晶状体(intraocular lens,IOL)计算公式预测屈光误差的影响。设计回顾性观察性研究。研究对象2019年1月1日至2021年12月31日在清华大学第一附属医院接受白内障手术,并囊袋内植入单焦非球面一片式IOL的连续病例176例(176眼)。方法所有患者术前测量术眼眼轴长度(axial length,AL)、角膜曲率及前房深度(aqueous depth,AD)。根据前房深度,将患者分为浅前房组(AD<2.5 mm)及非浅前房组(AD≥2.5 mm);再将浅前房的患者进一步分为短眼轴组(AL<22.0 mm)及非短眼轴组(AL≥22.0 mm)。术后1~3个月进行验光,验光结果与术前使用SRK/T、Hoffer Q、Haigis、Barrett 4种公式计算的预测屈光值进行比较。主要指标术后IOL度数的预测屈光误差(prediction error,PE)和绝对预测屈光误差(absolute prediction error,AE)。结果四个公式的PE值在浅前房组中有统计学差异(P<0.001),而在非浅前房组中无统计学差异(P=0.438)。浅前房组中不同公式的PE比较,Haigis公式(0.00±0.41)D与Barrett公式(0.04±0.41)D较SRK/T公式(-0.18±0.45)D和Hoffer Q公式(-0.21±0.41)D小(P<0.05),Haigis与Barrett公式之间无明显差异(P=0.614)。在浅前房短眼轴组内,PE在SRK/T公式(-0.41±0.56)D和Hoffer Q公式(-0.45±0.44)D公式中呈明显的近视漂移,与Haigis公式(0.05±0.42)D相差可以达到0.50 D(P<0.05)。同一公式自身组间对比:浅前房的情况下,PE在SRK/T与Hoffer Q公式出现近视漂移[P(SRK/T)=0.031,P(Hoffer Q)<0.001]。不同公式的AE值在浅前房组(P=0.393)及非浅前房组(P=0.369)均无统计学差异,组间对比也无统计学差异(P>0.05)。浅前房组内,SRK/T公式(P=0.044)和Hoffer Q公式(P=0.02)短眼轴组较非短眼轴组的AE更大。AE在0.50D范围内的比例,浅前房短眼轴组各公式间差异较大(Haigis公式90%,Hoffer Q公式仅50%),但无统计学意义(P=0.098)。Logistic回归分析显示,术前角膜越陡峭(OR=1.71)、眼轴越长(OR=2.03),前房越浅(OR=0.327),SRK/T公式的AE>0.50 D的概率越大;而Barrett、Haigis、Hoffer Q公式与这3个因素的相关性不显著。结论在浅前房患者中,Haigis和Barrett公式预测的准确性较SRK/T和Hoffer Q公式高,推荐临床使用。

Objective To investigate the effect of shallow aqueous depth(AD)on the prediction error of four different intraocular lens(IOL)calculation formulas.Design Retrospective observational study.Participants A total of 176 cataract patients(176 eyes)who had cataract surgery with single focus IOL in-the-bag implantation from the First Hospital of Tsinghua University from Jan 1st,2019 to Dec.31th,2021.Methods Axial length(AL),corneal curvature and AD were measured before operation.Patients were divided into shallow AD group(AD<2.5 mm)and non-shallow AD group(AD≥2.5 mm)according to AD.And the shallow AD group was further divided into short AL(AL<22.0 mm)and normal AL(AL≥22.0 mm)subgroups.Manifest refraction results were collected 1 to 3 months after operation to calculate the postoperative prediction errors of SRK/T,Hoffer Q,Haigis and Barrett formulas.Main Outcome Measures The prediction error(PE)and absolute prediction error(AE)of IOL values after operation.Results The difference of PE of 4 formulas was statistically significant(P<0.001)in the shallow AD group,while not in the non-shallow AD group(P=0.438).In the shallow AD group,the PE of Haigis(0.00±0.41)D and Barrett(0.04±0.41)D were smaller than that of SRK/T(-0.18±0.45)D and Hoffer Q(-0.21±0.41)D(P<0.05),there were no significant difference in the PE between Haigis and Barrett(P=0.614).In the shallow AD short AL group,the PE of SRK/T(-0.41±0.56)D and Hoffer Q(-0.45±0.44)D tended towards nearly a 0.50 D myopic shift which was statistically different from Haigis[(0.05±0.42)D,P<0.05].Compared with itself,the PE of SRK/T and Hoffer Q tended towards a myopic shift under the influence of shallow AD[P(SRK/T)=0.031,P(Hoffer Q)<0.001].There was no significant difference in the AE of different formulas within the group(the shallow AD group,P=0.393,and non-shallow AD group,P=0.369)nor between(P>0.05).In the shallow AD group,AE of SRK/T(P=0.044)and Hoffer Q(P=0.02)was statistically bigger in the short AL group.In the shallow AD short AL group,the percentage of AE within 0.50 D was 90%of Haigis,and only 50%of Hoffer Q without statistically difference(P=0.098).Through Logistic regression analysis,only SRK/T was found a greater possibility to get a>0.50 D AE with a steeper cornea(OR 1.71),a longer AL(OR 2.03)and a shallower AD(OR 0.327).Conclusions In patients with shallow AD,Haigis and Barrett formulas had more accurate predictions than SRK/T and Hoffer Q formulas.These two formulas were recommended in clinical practice.