Intracameral Phenylephrine 1.5% for Prophylaxis against Intraoperative Floppy Iris Syndrome: Prospective, Randomized Fellow Eye Study

Abstract

To evaluate the efficacy of intracameral phenylephrine (IPH) administered as prophylaxis against intraoperative floppy iris syndrome (IFIS) and to analyze the ability of IPH to reverse IFIS. Prospective, multicenter, randomized, comparative case series of fellow eyes. Forty-two patients receiving tamsulosin who underwent cataract surgery between January and April 2011. Phacoemulsification was performed by 2 experienced surgeons at 2 surgical sites (Complexo Hospitalario Universitario Orense and Complexo Hospitalario Universitario A Coruña). One eye of each patient was randomized to receive 0.6 ml of nonpreserved bisulfite-free IPH 1.5% (group 1) or balanced saline solution (group 2) at the start of surgery. If significant miosis or iris prolapse occurred, IPH was injected during phacoemulsification in group 2. No changes were performed in the surgeon's standard fluidic parameters or viscoelastic preferences. Routine topical mydriatics were instilled before surgery. Intraoperative iris billowing and prolapse and pupil size were recorded and videotaped. Surgical complications; adverse events; pre- and postoperative pulse rate and blood pressure; and final best-corrected visual acuity (BCVA), intraocular pressure (IOP), and endothelial cell count (ECC) were recorded. Incidence of IFIS and change in pupil size after IPH administration in those eyes of group 2 requiring IPH because of significant miosis or iris prolapse. Signs of IFIS were observed in 88.09% of eyes in group 2. No signs of IFS were noted in group 1 (P < 0.001). Significant miosis, iris prolapse, or both occurred in 54.76% of eyes in group 2, although the condition was successfully reverted with IPH, with a significant increase in pupil size after IPH administration (from 4.77±0.88 mm to 6.68±0.93 mm; P=0.000). No intraoperative complications occurred. No significant differences in ECC, BCVA, or IOP were detected between IPH-treated and nontreated eyes. Blood pressure/pulse rate did not differ significantly from preoperative values in IPH-treated cases. Intracameral phenylephrine is a highly efficient measure for prophylaxis against IFIS. Moreover, the drug can reverse IFIS, restoring iris rigidity and causing the pupil to return to its preoperative size.