PREDICTIVE VALUE OF ANTERIOR SEGMENT PARAMETERS FOR POST-OP ANTERIOR CHAMBER DEPTH AFTER IOL IMPLANT

Abstract

Objective: This study was conducted to predict the post-operative anterior chamber depth depending on pre-operative parameters. Methods: 50 patients coming in Mayo hospital with lenticular changes underwent biometry for intraocular lens power calculation. By using keratometer, K-readings of the cornea and by using A-scan, the axial length (AL) of the eyeball, anterior chamber depth and crystalline lens thickness measured while the patient laying in supine position. Then measured the IOL power using the SRK-II formula. After cataract surgery, again measured the anterior chamber depth by using A-scan to see any change in the depth of the anterior chamber and the effect of various ocular parameters. Results: Pre-operative anterior chamber depth (pre-ACD) mean was 2.98±0.42 mm. Post-operative anterior chamber depth (Post-ACD) was 4.41±0.40 mm. The change was statistically significant with p<0.001 (Paired sample t-Test).The mean increase of ACD was 1.43±0.28 mm ranging from 0.21 to 2.26 mm. The parameter that showed significant correlation with the post-ACD was pre-ACD with r²=0.62 and anterior segment length (ASL) with r²=0.4. Other parameters do not influence post-ACD much. Conclusion: This study proposes following regression formula to calculate post-ACD, preoperatively. Post-ACD = 4.14 + 1.13*Pre-ACD + 0.38*LT – (0.02*WTW + 0.42*ASL + 0.17*K_avg)