Modified Capsulorhexis vs. Envelope Capsulotomy in Extracapsular Cataract Surgery

Abstract

OBJECTIVES: To evaluate prospectively the effect of a modified capsulorhexis technique on the degree of intraocular lens (IOL) centration in patients undergoing extracapsular cataract extraction (ECCE). Patients were randomized to have envelope capsulotomy (EC) in group 1 or a continuous circular capsulorhexis (CCC) with 1 relieving anterior capsule incision at 11 o'clock in group 2. STUDY DESIGN: Prospective study. SETTING: Liverpool, District general hospital. MAIN OUTCOME MEASURES: Observed mean optic decentration and maintenance of capsular fixation in both groups after a mean of 12.7 months follow-up. RESULTS: Mean optic decentration was 0.51 mm in group 1(26 eyes) as compared to 0.19 mm in group 2 (28 eyes). This was statistically significant (2-sample t-test, t = 3.045, 38 d.f., P = 0.0042). Loss of capsular fixation was observed in 5 eyes (20%) in group 1 where a haptic migrated superiorly out of the capsular bag. CONCLUSIONS: Excellent IOL centration is achieved by using this modified CCC technique. A relieving incision prevents inadvertent intracapsular delivery of the lens and the superior location of the incision facilitates ‘in-the-bag’ placement of the IOL with the haptics orientated to the 3 and 9 o'clock positions. This safe modified CCC technique is well suited for routine ECCE.