Best Prophylactic Strategy in Groups at Risk of Intraoperative Floppy Iris Syndrome Development: Comparison Between Atropine Instillation and Adrenaline Intracameral Injection.

Background: Intraoperative Floppy Iris Syndrome (IFIS) is an important cause of surgical complications and iris defects in patients undergoing phacoemulsification that were treated with selective subtype α1A receptor antagonists for a long period of time. To date, no definitive preventive strategy has emerged, yet. The need of prophylaxis is dictated by the high prevalence of males affected by benign prostatic hyperplasia undergoing cataract surgery.

Objective: To identify the best prophylactic strategy in groups at risk of IFIS development by comparing two mydriatic treatments in course of phacoemulsification surgery.

Methods: 81 eyes of 81 patients in treatment with Tamsulosin were enrolled in the study. 43 eyes were treated with atropine sulfate 1% while 38 eyes received an injection of mydriatic solution containing epinephrine in the anterior chamber. All phacoemulsifications were videotaped in order to assess the occurrence of IFIS and the severity of the syndrome.

Results: The treatment group showed a statistically significant reduction (p = 0.0115) of floppy iris syndrome incidence, from 86.05% (37/43) of the atropine group to 60.53% (23/38). The analysis showed a reduction of IFIS mild form only, whereas the incidence of severe forms remained unchanged.

Conclusions: We believe that IFIS may arise through two different mechanisms: pharmacological antagonism and anatomical modifications. Patients suffering from mild forms of the disease showed a statistically significant reduction of IFIS incidence after intraoperative prophylaxis due to epinephrine's ability to displace Tamsulosin, resulting in the increase of iris tone when the disease is caused mainly by receptorial antagonism. On the contrary, prophylaxis does not deliver any valuable result in case of severe forms where the anatomical variations play a major role.