[Analysis of changes of anterior chamber depth after IOL implantation]

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.

Preoperative and postoperative ACD were examined in 117 patients (177 eyes) 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.

(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 A-constant 118.0 and that of 118.4 (P = 0.957).

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.