The role of preoperative subconjunctival mydricaine and topical diclofenacsodium 0.1% in maintaining mydriasis during vitrectomy

Purpose: To establish the role of preoperative subconjunctival mydricaine a nd diclofenac 0.1% in maintaining mydriasis during vitrectomy. Methods: Fifty-seven patients were entered into the study. All were given c yclopentolate 1% and phenylephrine 2.5% preoperatively. Each patient was ra ndomly allocated to one of three groups. In Group 1, patients received mydr icaine by subconjunctival injection and diclofenac 0.1% topically preoperat ively. In Group 2, patients received only subconjunctival mydricaine, Group 3 patients received only topical diclofenac preoperatively. Pupil diameter was measured with calipers before and at the end of the operation. Results: There was no statistically significant difference in the change in pupil size between Groups 2 and 3. In all patients in Group 1 (who receive d both subconjunctival mydricaine and diclofenac preoperatively), pupil siz e was either maintained or increased after vitrectomy. This result was stat istically significant when compared with the other groups (for Group 1 vers us Group 2, P < 0.005; for Group 1 versus Group 3, P < 4.7 X 10(-06)). Conclusion: Topical diclofenac is useful for maintaining pupil size during vitrectomy only when used in conjunction with subconjunctival mydricaine, e specially in patients in whom prolonged surgery is anticipated.