98th Annual Meeting DOG 2000

K 750

Medical control of intraocular pressure (IOP) after small incision cataract surgery: A comparison of different antiglaucomatous eye drops

O. Schwenn1, N. Xia1, F. Krummenauer2, H. B. Dick1

Purpose: To compare the ocular hypotensive effect of different antiglaucomatous eye drops. A second objective was to compare the effects on flare and central corneal thickness (CCT).

Patients and Methods: In this double-masked, randomized study 119 eyes of 119 patients without other ocular pathology undergoing standardized (one surgeon, Healon â ) small incision cataract surgery with foldable intraocular lens implantation were included and assigned to one of 5 groups: group I: 0.25% Timolol in Gelrite (extended efficacy, n=23); group II: 2% dorzolamide (n=24); group III: combination of 0.5% Timolol plus 2% dorzolamide (n=22); group IV: Brimonidine (n=26); group V: Gentamicine (control, n=24). IOP was measured preoperatively and at 3±1, 6±1, 9±1, 24±3 and 48±3 hours postoperatively. Laser flare measurements and corneal pachymetry were performed preoperatively and at 6±1, 24±3 and 48±3 hours postoperatively. Statistical interference was based on nonparametric group comparisons by Wilcoxon tests. Absolute values (static comparisons) and intraindividual changes to preoperative measurements (dynamic comparisons) were evaluated. All p-values should be regarded as descriptive, since they were not formally adjusted for multiplicity. A p-value <0.05 therefore indicates local statistical significance.

Results: There were no differences between the groups according to age, phacoemulsification time, axial length, preoperative IOP and flare, but preoperative CCT was lower in group II and III compared to group V. A statistically significant IOP decrease was measured in group I at 24 (p=0.028) and 48 hours (p=0.007) and in group III at 3 (p<0.001), 6 (p<0.001), 24 (p<0.001) and 48 hours (p<0.001) after surgery. A statistically significant IOP increase occured in group IV at 3 (p=0.001), 6 (p<0.001) and 9 hours (p<0.001) and in group V at 3 (p<0.001), 6 (p<0.001), 9 (p<0.001) and 24 hours (p=0.002) postoperatively. Group I, II and group III demonstrated lower IOPs at different time points in comparison to group IV and V. Besides, group III had lower IOPs at 3 hours (compared to group I) and at 6 hours (compared to group II) postoperatively. No statistical differences in IOP between the group were found after 48 hours. Dynamic group comparisons demonstrated highest flare values in group III and I.

Conclusion: The results favor a combination of 0.5% Timolol plus 2% dorzolamide to control postoperative IOP elevation.

1Department of Ophthalmology, University of Mainz, Langenbeckstraße 1,D-55131 Mainz, Germany,
Coordination centre for Clinical Trials, Johannes-Gutenberg-University, Mainz