人工晶状体植入术后前房深度的变化分析

Analysis of changes of anterior chamber depth after IOL implantation

目的探讨人工晶状体（IOL）植入术后前房深度（ACD）的变化及其相关因素,以获得理想的术后屈光状态. 方法收集行白内障超声乳化吸除IOL植入术,术后随访资料完整的117例（177只眼）白内障患者,分析其术后ACD变化及其与眼轴长度、角膜屈光力和IOL A常数的关系.随访时间为3～24个月.结果 177只眼IOL植入术前平均ACD为（3.19±0.39） mm,术后平均ACD为（4.22±0.65） mm,两者比较,差异有统计学意义（P=0.000）.177只眼术后ACD的平均变化值为（1.03±0.61）mm;术后ACD的变化值随眼轴长度和角膜屈光力的增加而增大,呈线性正相关（r=0.866,0.946;P=0.001）.IOL A常数为118.0、118.4和118.9,3组术前ACD与术后比较,差异均有统计学意义（P〈0.01）;A常数为118.9组的术后ACD变化值与A常数为118.0和118.4的组比较,差异均有统计学意义（P〈0.05）;A常数为118.0的组与118.4的组比较,差异无统计学意义（P=0.957）. 结论 IOL植入术后ACD因眼轴长度、角膜屈光力和IOL A常数等因素的不同而不同程度地增加.在研究IOL屈光度数计算公式的准确性和调整公式的计算值时,应考虑术后ACD的变化及其相关因素.

Objective To evaluate the changes of the anterior chamber depth （ACD） and the related factors after cataract surgery with IOL implantation in order to achieve the intended postoperative refraction. Methods Preoperative and postoperative ACD were examined in 117 patients （177eyes） who underwent cataract surgery （phacoemulsification and posterior chamber IOL implantation ）. Correlations between changes of ACD and the axial lengths of the eyes, K-readings and IOL A-constants were assessed. Patients were followed-up for 3 to 24 months. Results （ 1 ） There was significant difference between preoperative ACD （3.19 ± 0.39 ）mm and postoperative ACD （4.22 ± 0.65 ） mm（ P = 0. 000）. （ 2 ） The mean postoperative ACD change was （ 1.03 ± 0. 61 ） mm. The correlations between the ACD changes and the axial lengths of the eye and K-readings were statistically significant. （ r = 0. 866, r = 0. 946, P = 0. 001 ）. （3） There was significant difference between preoperative ACD and postoperative ACD in the three different A-constants groups （ 118.9, 118.0 and 118.4 ） （ P = 0. 004,0. 001 and 0. 001 ）. There was significant difference between ACD changes in patients with A-constant 118.9 and that of 118.0 or 118.4 （P =0.007, P = 0. 01 ）. There was no significant difference between ACD changes in patients with Aconstant 118.0 and that of 118.4 （P = 0.957）. Conclusion Cataract surgery deepened anterior chambers at varying degrees, depending on the axial lengths of the eye, K-readings and the IOL A-constants. ACD changes and relevant factors should be considered in studying the accuracy of IOL refraction formula and in adjusting the calculated data.