Purpose: To determine whether intracameral mydriatics can redilate pupils that contract during phacoemulsification cataract surgery.
Methods: A total of 80 patients were included in this prospective, randomized, double-blind study performed at Örnsköldsviks Hospital Eye Clinic. Of these, 60 patients had 0.6 µg/ml of epinephrine added to the balanced salt solution (BSS) used for irrigation and 20 patients did not. The patients in each group were randomized and given either an intracameral mydriatics (ICM) solution or placebo intracamerally after phacoemulsification and cortex cleaning. The pupil size was registered preoperatively, after cortex cleaning, 30 seconds after study injection, 2 mins after study injection and the day after surgery.
Results: No clinically relevant differences were found preoperatively. In the epinephrine material a significantly longer operation time (p = 0.023) and more procedures requiring Vision Blue™ and Kelman-type tip in the placebo group might indicate diversity in the grade of cataract. There was a greater degree of contraction in the absence of epinephrine in the irrigation solution (2.3 ± 1.0 mm in the ICM group and 3.2 ± 0.7 mm in the placebo group) compared to in the presence of epinephrine. With no epinephrine ICM significantly redilated the pupils at 30 seconds (p ≤ 0.001) as well as at 2 mins (p = 0.015).
Conclusion: We have shown that in cases with an intraoperative pupil contraction, ICM is effective in redilating the pupil. Insufficient adrenergic stimulation of the pupil dilator appears to be a major factor causing intraoperative pupil contraction during phacoemulsification cataract surgery.