短眼轴眼中5种人工晶状体计算公式比较
Evaluation of intraocular lens powers in eyes with short axial lengths

目的 ·比较SRK-Ⅱ、SRK/T、Haigis、Hoffer Q、Holladay这5种人工晶状体屈光度计算公式在预测短眼轴眼白内障患者术后屈光度时的准确性。方法 ·纳入眼轴＜22 mm的白内障患者共42例55眼，行白内障超声乳化联合人工晶状体植入术。术前用IOL Master测量角膜曲率、前房深度和眼轴长度，运用SRK-Ⅱ、SRK/T、Haigis、Hoffer Q、Holladay公式计算术后预期屈光度。术后3～6个月随访，验光测量患者术后实际屈光度，比较实际屈光度和预期屈光度的误差值。结果 · 55眼中用SRK-Ⅱ、SRK/T、Haigis、Hoffer Q、Holladay公式计算术后预期屈光度时，分别有28、26、27、20、24眼实际屈光度发生远视偏移，27、29、28、35、31眼发生近视偏移。发生远视偏移的误差值间差异无统计学意义（F=1.351，P=0.225）；发生近视偏移的误差值间差异有统计学意义（F=6.276，P=0.000），Hoffer Q和Holladay公式误差值较小，Haigis公式得出的术后实际屈光度发生近视偏移的误差值显著大于其他各公式（P=0.000）。此外，各公式绝对误差值≤0.25 D的分别有11、12、11、21、16眼，但5种公式绝对误差值的总体分布差异无统计学意义（P=0.163）。结论 ·计算短眼轴眼白内障患者术后预期屈光度，Hoffer Q和Holladay公式预测的准确性较好，Haigis公式较其他公式有一定引起近视的倾向。
： Objective · To evaluate the predictive accuracy of SRK-Ⅱ , SRK/T, Haigis, Hoffer Q, and Holladay formulas on postoperative refraction error values in cataract patients with short axial length eyes. Methods · Fifty-five short axial length eyes of 42 patients with cataract were recruited. All the patients underwent phacoemulsification surgery and posterior chamber intraocular lens implantation. Corneal curvature, anterior chamber depth and axial length were measured by IOL Master before the surgery. SRK-Ⅱ, SRK/T, Haigis, Hoffer Q, and Holladay formulas were adopted to calculate predictive refraction after operation. Three to six months after operation follow-up visits were carried out to measure the refractive power of all the eyes and calculate the differences between the actual refraction powers and the predicted. Results · Among the 55 eyes, there were 28, 26, 27, 20, and 24 eyes shifting to hyperopias and 27, 29, 28, 35, and 31 eyes to myopia according to SRK-Ⅱ, SRK/T, Haigis, Hoffer Q, and Holladay formula, respectively. The values of postoperative myopic shift were statistically different among the 5 formulas (F=6.276, P=0.000), but those of the postoperative hyperopic shift were not (F=1.351, P=0.225). Hoffer Q and Holladay formula showed good accuracy. Haigis formula leaded to more myopia (P=0.000). In addition, there were 11, 12, 11, 21, and 16 eyes with less than 0.25 D of absolute errors calculated by SRK-Ⅱ, SRK/T, Haigis, Hoffer Q, and Holladay formula, respectively. However, the distribution of the absolute errors of 5 formulas was not statistically significant (P=0.163). Conclusion · In short axial length eyes, Hoffer Q and Holladay formula showed a good accuracy. Haigis formula leads to more myopia