圆锥角膜人工晶状体屈光力计算优化算法的初步验证

Preliminary validation of an optimized algorithm for intraocular lens power calculation in keratoconus.

作者信息

Camps Vicente J, Piñero David P, Caravaca Esteban, De Fez Dolores

机构信息

Department of Optics, Pharmacology and Anatomy, University of Alicante, Alicante, Spain.

Department of Optics, Pharmacology and Anatomy, University of Alicante; Department of Ophthalmology (Oftalmar), Vithas Medimar International Hospital, Alicante, Spain.

出版信息

Indian J Ophthalmol. 2017 Aug;65(8):690-699. doi: 10.4103/ijo.IJO_274_16.

DOI:10.4103/ijo.IJO_274_16

PMID:28820154

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC5598179/

Abstract

PURPOSE

This study aimed to evaluate the theoretical influence on intraocular lens power (PIOL) calculation of the use of keratometric approach for corneal power (Pc) calculation in keratoconus and to develop and validate an algorithm preliminarily to minimize this influence.

METHODS

Pcwas calculated theoretically with the classical keratometric approach, the Gaussian equation, and the keratometric approach using a variable keratometric index (nkadj) dependent on r1c(Pkadj). Differences in PIOLcalculations (ΔPIOL) using keratometric and Gaussian Pcvalues were evaluated. Preliminary clinical validation of a PIOLalgorithm using Pkadjwas performed in 13 keratoconus eyes.

RESULTS

PIOLunderestimation was present if Pcwas overestimated, and vice versa. Theoretical PIOLoverestimation up to -5.6 D and -6.2 D using Le Grand and Gullstrand eye models was found for a keratometric index of 1.3375. If nkadjwas used, maximal Δ PIOLwas ±1.1 D, with most of the values ≤±0.6 D. Clinically, PIOLunder- and over-estimations ranged from -1.1 to - 0.4 D. No statistically significant differences were found between PIOLobtained with Pkadjand Gaussian equation (P > 0.05).

CONCLUSION

The use of the keratometric Pcfor PIOLcalculations in keratoconus can lead to significant errors that may be minimized using a Pkadjapproach.

摘要

目的

本研究旨在评估圆锥角膜中使用角膜曲率计法计算角膜屈光力（Pc）对人工晶状体度数（PIOL）计算的理论影响，并初步开发和验证一种算法以最小化这种影响。

方法

使用经典角膜曲率计法、高斯方程以及使用依赖于r1c（Pkadj）的可变角膜曲率计指数（nkadj）的角膜曲率计法从理论上计算Pc。评估使用角膜曲率计法和高斯法得到的Pc值时PIOL计算（ΔPIOL）的差异。对13只圆锥角膜眼进行了使用Pkadj的PIOL算法的初步临床验证。

结果

如果Pc被高估，则PIOL会被低估，反之亦然。对于角膜曲率计指数为1.3375的情况，使用Le Grand和Gullstrand眼模型发现理论上PIOL高估高达-5.6 D和-6.2 D。如果使用nkadj，最大ΔPIOL为±1.1 D，大多数值≤±0.6 D。临床上，PIOL的低估和高估范围为-1.1至-0.4 D。使用Pkadj和高斯方程得到的PIOL之间未发现统计学上的显著差异（P>0.05）。