Pupil size with and without adrenaline with diclofenac use before cataract surgery.

Purpose: To determine whether adrenaline in the irrigating solution is necessary when diclofenac eyedrops are used before cataract surgery.

Setting: Pasqua Hospital, Regina, Saskatchewan, Canada.

Methods: In this prospective randomized masked study, all patients used diclofenac eyedrops 2 days preoperatively. The pupils were dilated with a wick soaked in a dilating solution containing diclofenac. Patients were divided into 2 groups. One group had 0.5 mL of 1:1000 adrenaline in 500.0 mL of fortified balanced salt solution (BSS Plus) (adrenaline group). The other group did not (no-adrenaline group). The horizontal diameter of the pupils was measured with calipers.

Results: The study included 207 patients. There were no surgical complications. In the adrenaline group, the mean pupil size was 8.19 mm +/- 0.86 (SD) before the first incision, 8.14 +/- 0.87 mm after phacoemulsification, and 8.14 +/- 0.85 mm after cortical removal. In the no-adrenaline group, the means were 8.19 +/- 0.87 mm, 7.94 +/- 0.99 mm, and 7.87 +/-1.03 mm, respectively. The mean pupil constriction was 0.05 +/- 0.21 mm in the adrenaline group and 0.33 +/- 0.43 mm in the no-adrenaline group. The difference was statistically significant (Mann-Whitney test). Further analysis of preoperative pupil size showed a significant difference for smaller pupils only.

Conclusions: When diclofenac eyedrops were used before cataract surgery, the smaller preoperative pupils constricted significantly less when adrenaline was added to the irrigating solution. This was not true for larger pupils. Thus, adrenaline in the irrigating solution does not appear necessary in eyes with large preoperative pupils.