Intraoperative Iris Behavior during Phacoemulsification Maneuvers in Rabbits Treated with Selective α1-Blocker, 5α-Reductase Inhibitor, or Anxiolytic Medication

This prospective, experimental study aims to evaluate the association between administration of α-blocker, 5α-reductase inhibitor, or anxiolytic medications and intraoperative floppy iris syndrome (IFIS) using a rabbit animal model. A total of 31 Metis rabbits were distributed into four groups as follows: 10 rabbits given tamsulosin, 10 rabbits given finasteride, 5 rabbits who received lorazepam, and 6 treatment-naive animals in the control group. Dosing was calculated according to body surface area ratio of man to rabbit, with a dosing duration of 43 days for all groups. Phacoemulsification maneuvers were performed by a single surgeon, who was blinded to group allocation. Any intraoperative billowing of the iris was noted and subsequently graded from 0 to 3. Higher incidences of iris billowing were found in the tamsulosin-dosed animals [OR = 8.33 (CI 95% 0.63-110.09)], (<i>p</i> = 0.13), the finasteride group [OR = 11.6 (CI 95% 0.92-147.6)], (<i>p</i> = 0.11), and the lorazepam group [OR = 7.5 (CI 95% 0.45-122.8)], (<i>p</i> = 0.24), as opposed to the control. Administration of α-blocker tamsulosin, 5α-reductase inhibitor finasteride, or anxiolytic medication lorazepam induces altered intraoperative iris behavior. These results correspond with previous studies and further solidify the hypothesis that systemic medication, administered both long and short-term, influences surgical parameters in cataract surgery. The present study can become the basis for further clinical or experimental research.