Department of Ophthalmology, Ameer-ud-Din Medical College, Postgraduate Medical Institute, Lahore General Hospital, Lahore, Pakistan.
Institute of Molecular Biology and Biotechnology / Centre for Research in Molecular Medicine, The University of Lahore, Lahore, Pakistan.
J Pak Med Assoc. 2022 Jul;72(7):1373-1377. doi: 10.47391/JPMA.3842.
To compare the accuracy of SRK/T, Barrett Universal II and Hill radial basis activation function-2 formulas in intraocular lens power calculation using different axial lengths.
The retrospective study was conducted at the Lahore General Hospital, Lahore, Pakistan, and comprised data from June to December 2020 of patients who underwent phacoemulsification with non-toric, monofocal intraocular lens implantation. Data was sorted in 3 groups on the basis of axial length; group 1 22-25mm, group 2>25mm, and group 3 <22mm. Intraocular lens power was calculated using SRK/T with IOL Master, while online calculators were used for Barrett Universal II and Hill radial basis activation function-2 formulas. Data was analysed using SPSS 21.
Of the 100 patients, 47(347%) were males and 53(53%) were females. There were 49(49%) diabetics, and 57(57%) were right eyes. There were 77(77%) patients with mean age 62.38±9.5 in group 1, 17(17%) patients with mean age 52.59±12.78 in group 2, and 6(6%) patients with mean age 61.33+7.61 years in group 3. Mean axial length in group 1 was 23.55±0.81mm with anterior chamber depth of 3.1± 0.37mm. In group 2, mean axial length was 27.54±2.8mm, with anterior chamber depth of 3.4±0.15mm. In group 3, mean axial length was 21.74mm, with anterior chamber depth of 3.14±0.44mm. Mean prediction error of SRK/T versus Barrett Universal II was 0.092±0.041D (p=0.078), SRK/T versus Hill radial basis activation function-2 was 0.066±0.037D (p=0.221) and Barrett Universal versus Hill radial basis activation function-2 was -0.025±0.019D (p=0.553). Mean prediction error of group 1 versus group 2 was -0.105±0.14D, group 2 versus group 3 was 0.046±0.216D and group 2 versus group 3 was 0.151±0.243D (p=1.0). In 74% eyes, absolute prediction error was within ±0.5D in group 1, 64% in group 2 and 50% in group 3 for all formulas.
SRK/T formula was found to be as reliable as Barrett Universal II and Hill radial basis activation function-2 in terms of calculating intra ocular lens power for all axial lengths.
比较 SRK/T、Barrett Universal II 和 Hill 径向基激活函数-2 公式在不同眼轴长度下计算人工晶状体屈光力的准确性。
这是一项在巴基斯坦拉合尔总医院进行的回顾性研究，纳入了 2020 年 6 月至 12 月期间接受超声乳化白内障吸除术并植入非散光、单焦点人工晶状体的患者的数据。根据眼轴长度将数据分为 3 组：第 1 组 22-25mm，第 2 组>25mm，第 3 组<22mm。使用 IOL Master 计算 SRK/T 公式的人工晶状体屈光力，而在线计算器则用于 Barrett Universal II 和 Hill 径向基激活函数-2 公式。数据使用 SPSS 21 进行分析。
在 100 名患者中，男性 47 名（34.7%），女性 53 名（53%）。49 名（49%）为糖尿病患者，57 名（57%）为右眼。第 1 组平均年龄 62.38±9.5 岁的患者有 77 名（77%），第 2 组平均年龄 52.59±12.78 岁的患者有 17 名（17%），第 3 组平均年龄 61.33+7.61 岁的患者有 6 名（6%）。第 1 组的平均眼轴长度为 23.55±0.81mm，前房深度为 3.1±0.37mm。第 2 组的平均眼轴长度为 27.54±2.8mm，前房深度为 3.4±0.15mm。第 3 组的平均眼轴长度为 21.74mm，前房深度为 3.14±0.44mm。SRK/T 与 Barrett Universal II 的平均预测误差为 0.092±0.041D（p=0.078），SRK/T 与 Hill 径向基激活函数-2 的平均预测误差为 0.066±0.037D（p=0.221），Barrett Universal 与 Hill 径向基激活函数-2 的平均预测误差为-0.025±0.019D（p=0.553）。第 1 组与第 2 组的平均预测误差为-0.105±0.14D，第 2 组与第 3 组的平均预测误差为 0.046±0.216D，第 2 组与第 3 组的平均预测误差为 0.151±0.243D（p=1.0）。在所有公式中，第 1 组 74%的眼的绝对预测误差在±0.5D 以内，第 2 组 64%的眼的绝对预测误差在±0.5D 以内，第 3 组 50%的眼的绝对预测误差在±0.5D 以内。
在所有眼轴长度下，SRK/T 公式与 Barrett Universal II 和 Hill 径向基激活函数-2 公式在计算人工晶状体屈光力方面同样可靠。
