Efficacy of 2% Ibopamine on the Dilation of Patients with Pseudoexfoliation Syndrome

Abstract

To compare the mydriatic effects of 2% ibopamine and collyrium containing 10% phenylephrine + 0.5% tropicamide and to study the associated drug in patients with ocular pseudoexfoliation (PEX) syndrome. This was a prospective, comparative, interventional clinical study. The study group consisted of 20 patients with ocular PEX syndrome. Intervention procedures included administration of 10% phenylephrine-0.5% tropicamide versus 2% ibopamine versus 2% ibopamine followed by the combination drug. Main outcome measurement was mydriatic efficacy measured in terms of mean pupil diameter. Adverse effects on intraocular pressure (IOP) were measured with a Goldmann applanation tonometer. Mean premedication pupil diameters in all patients were less than 3.5 mm. Instillation of 10% phenylephrine-0.5% tropicamide caused significantly greater mydriasis than 2% ibopamine (pupil diameters: 6.17 mm, SD=1.14 versus 5.33 mm, SD=1.34; p<0.001). Combined use of both collyria significantly increased mydriasis (7.19 mm; SD=0.69) compared with that induced by either of the products alone (p<0.001). Inadequate mydriasis (pupil diameters < 5.5 mm) was observed in 2 patients after administration of 10% phenylephrine-0.5% tropicamide and in 10 following instillation of 2% ibopamine, but the addition of 10% phenylephrine -0.5% tropicamide to ibopamine-treated eyes resulted in adequate dilation in all cases. IOP increases of 4 mmHg over baseline values were observed in 12 (60%) patients after 2% ibopamine. In patients with ocular PEX, instillation of 2% ibopamine exerts a significant additive effect on mydriasis induced with 10% phenylephrine-0.5% tropicamide with only minimal increases in IOP.