Effect of intraocular lens fixation on acute intraocular pressure rise after neodymium-YAG laser capsulotomy.

SUMMARY Neodymium-YAG laser posterior capsulotomy is asso­ ciated in some cases with an acute rise in the intraocular pressure (lOP), possibly caused by blockage of the trabecnlar meshwork by debris. To test the hypothesis that the lOP rise is preventable if fixation of the intraocular lens (IOL) in the capsular bag is ensured, we conducted a study comparing lOP changes at 1, 2, 3 and 24 hours after Nd:YAG capsulotomy between eyes with capsular bag-fixated, one haptic in the bag (haptic inlout) and ciliary sulcus-fixated IOLs. Analysis of variance for repeated measures showed that after capsulotomy there were significant increases in lOP from baseline (p<0.05) in both the sulcus-fixated (1, 2 and 3 hours) and haptic inlout groups (2 and 3 hours), while lOPs in the bag-fixated group did not show any significant increase. The increases in lOP in the sulcus­ fixated group at 1, 2 and 3 hours after capsulotomy were significantly higher than the lOP changes at the corresponding periods in the other two groups (Krus­ kal-Wallis test, psulcus-fixated group (11.33 ± 7.85 mmHg) was significantly higher than that in the haptic inlout group (3.89 ± 7.14 mmHg) and the bag-fixated group (1.10 ± 2.71 mmHg), while there was no difference between the latter two groups. In 57.5% of the sulcus-fixated group, S% of the haptic inlout group and none of the eyes of the bag-fixated group the lOP rise was more than 10 mmHg. A significantly larger proportion of sulcus­ fixated eyes had anterior chamber cells and capsular debris after capsulotomy (i test, phaptic inlout group significant correlation (-0.56, P = 0.009) between lOP rise at 1 hour and the percentage enclosure of the IOL by the anterior capsule was demonstrated. There was no significant difference in maximum lOP rise between glaucomatous and non­ glaucomatous eyes (Mann-Whitney V-test, p = 0.49).