Lawless Michael, Jiang James Y, Hodge Chris, Sutton Gerard, Roberts Timothy V, Barrett Graham
Vision Eye Institute Chatswood, Sydney, New South Wales, Australia.
Sydney Medical School, The University of Sydney, Sydney, New South Wales, Australia.
Clin Exp Ophthalmol. 2020 Aug;48(6):749-756. doi: 10.1111/ceo.13760. Epub 2020 Apr 27.
Intraocular lens (IOL) calculations in post-refractive cases remain a concern. Our study identifies improved options for surgeons.
To evaluate and compare the prediction accuracy of IOL power calculation methods after previous laser refractive surgery using standard keratometry (SK), measured posterior corneal astigmatism (PCA) and total keratometry (TK).
Retrospective consecutive cohort.
A total of 50 consecutive patients (72 eyes) at a private institution who underwent cataract surgery with prior laser refractive procedures.
Methods using SK included ASCRS mean, Barrett True-K no history, Haigis-L and Shammas IOL formulae. Barrett True-K using posterior values (True K TK), Haigis and Holladay 1 Double-K methods using TK were also assessed. Post-surgery refraction was undertaken at minimum 3 weeks following surgery.
Arithmetic and absolute IOL refractive prediction errors, variances in mean arithmetic IOL prediction error, and percentage of eyes within ±0.25D, ±0.50D, ±0.75D and ±1.00D of refractive prediction errors were compared.
The Barrett True-K (TK) provided the lowest mean refractive prediction error (RPE) and variance for both prior myopes and hyperopes undergoing cataract surgery. The Barrett True-K (TK) exhibited the highest percentages of eyes within ±0.50D, ±0.75D and ±1.00D of the RPE compared to other formulae for prior myopic patients.
Accuracy of IOL power calculations in post-laser eyes can be improved by the addition of posterior corneal values as measured by the IOLMaster 700. The use of total keratometry may supplement outcomes when no prior refraction history is known.
屈光手术后的人工晶状体（IOL）计算仍是一个令人关注的问题。我们的研究为外科医生确定了更好的选择。
使用标准角膜曲率计（SK）、测量的后角膜散光（PCA）和总角膜曲率计（TK）评估并比较先前激光屈光手术后IOL屈光度计算方法的预测准确性。
回顾性连续队列研究。
一家私立机构中50例连续患者（72只眼），这些患者既往接受过激光屈光手术，随后接受了白内障手术。
使用SK的方法包括美国白内障与屈光手术学会（ASCRS）平均值、无既往史的巴雷特True-K、海吉斯-L和沙马斯IOL公式。还评估了使用后表面值的巴雷特True-K（True K TK）、使用TK的海吉斯和霍拉迪1双K方法。术后至少3周进行术后验光。
比较算术和绝对IOL屈光预测误差、平均算术IOL预测误差的方差，以及屈光预测误差在±0.25D、±0.50D、±0.75D和±1.00D范围内的眼的百分比。
对于既往近视和远视患者接受白内障手术，巴雷特True-K（TK）提供了最低的平均屈光预测误差（RPE）和方差。与其他公式相比，对于既往近视患者，巴雷特True-K（TK）在RPE的±0.50D、±0.75D和±1.00D范围内的眼的百分比最高。
通过添加IOLMaster 700测量的后角膜值，可以提高激光术后眼IOL屈光度计算的准确性。当不知道既往屈光史时，使用总角膜曲率计可能会补充结果。
