silodosin and Iris-Diseases

To evaluate the correlation between silodosin and intraoperative floppy iris syndrome (IFIS) and compare it with other a1-adrenergic receptor antagonists (a1-ARAs) and other factors predisposing to IFIS.. From the patients who underwent phacoemulsification between 2014 and 2020, we identified all patients who, during their preoperative assessment, reported an a1-ARAs intake (exposed group). These patients were matched utilizing a propensity score matching analysis with an otherwise homogenous group of patients (control group) based on demographics and systemic/ocular comorbidities.. A total of 350 patients were included in each group. In the exposed group, 177 (50.6%) patients were exposed to tamsulosin, 105 (30%) to alfuzosin, 43 (12.2%) to silodosin. Regarding IFIS, it was observed in 21.5% of patients on tamsulosin (38/177), 11.4% on alfuzosin (12/105), 37.2% on silodosin (16/43), and 3.4% in the controlled group (12/350). In a multiple regression model analysis, the only two factors significantly associated with IFIS development were silodosin and tamsulosin yielding an adjusted odds ratio of 8.471 (95%CI 4.005-17.920) and 3.803 (95%CI 2.231-6.485), respectively.. Silodosin has been demonstrated as a predisposing factor, strongly correlated with IFIS development. These results should increase cataract surgeons' awareness to assess their patients preoperatively for exposure to silodosin carefully and employ the appropriate prophylactic measures to ameliorate the impact of silodosin intake on the surgical outcome.

Topics: Adrenergic alpha-1 Receptor Antagonists; Causality; Cohort Studies; Humans; Indoles; Intraoperative Complications; Iris; Iris Diseases; Phacoemulsification; Propensity Score; Sulfonamides

Intraoperative floppy iris syndrome is a variant of the small pupil syndrome that has been observed during cataract surgery in some patients currently or previously treated with α1 adrenergic blockers. It is important for cataract surgeons to predict the probable complications preoperatively. Our study aims to evaluate the static and dynamic pupil characteristics of patients treated with silodosin-a selective α1 adrenergic blocker-for benign prostate hypertrophy (BPH) and to compare these values with healthy subjects using an automatic quantitative pupillometry system.. A total of 74 BPH patients treated with silodosin for six months (group 1) and 30 healthy subjects (group 2) were enrolled in this prospective multidisciplinary cross-sectional study. Static and dynamic pupillometric measurements were obtained under optimized conditions, and the results were compared between the two groups.. Seventy-four male patients with a mean age of 63,35 ± 7,21 (46-77) years with BPH treated with silodosin and 30 normal male subjects with a mean age of 63,07 ± 4,73 (52-71) years were analyzed. There were statistically significant differences between the groups with regard to scotopic pupil diameter (PD), high photopic PD, and low photopic PD (p < 0.001, for each one). The patient group had statistically significant higher values of amplitude and velocity of pupil contraction and lower values of duration of pupil contraction and latency as well as duration and velocity of pupil dilation.. The static and dynamic pupil characteristics of subjects treated with silodosin for BPH are different from those of healthy eyes. In addition, our results may have shed light on the risk for intraoperative floppy iris syndrome (IFIS) before cataract surgery; thus, surgeons can be alert and take precautions.

Topics: Adrenergic alpha-1 Receptor Antagonists; Aged; Cross-Sectional Studies; Humans; Indoles; Intraoperative Complications; Iris Diseases; Male; Middle Aged; Prospective Studies; Prostatic Hyperplasia; Pupil

Topics: Adrenergic alpha-1 Receptor Antagonists; Aged; Humans; Indoles; Intraoperative Complications; Iris Diseases; Male; Phacoemulsification; Prolapse; Prostatic Hyperplasia

To determine the mechanism of intraoperative floppy-iris syndrome (IFIS) by examining the binding affinity of tamsulosin and silodosin to α-receptors and melanin pigment using control and α(2)-blocker chronically administered in rabbit models.. Department of Ophthalmology, Kitasato University School of Medicine, Kanagawa, Japan.. Experimental study.. The study was performed in isolated albino and pigmented rabbit iris dilators using pharmacologic and morphologic examinations.. For pharmacologic examinations, the mean pK(B) values (pK(B) = -log K(B), where -log K(B) is the equilibrium dissociation constant of the antagonist-receptor complex) of tamsulosin in albino and pigmented rabbits were 9.10 and 8.08 and those of silodosin, 10.3 and 8.11, respectively. The pK(B) values of tamsulosin and silodosin in albino rabbits were significantly higher than in pigmented rabbits. In the isolated rabbit iris dilator, the maximum contraction evoked by 10(-3) mol/L phenylephrine gradually decreased by repetitive application in the chronic α-blocker-administered models. For morphologic examinations, the sizes of the pigment granules of pigment epitheliums for the α-blocker-administered models were irregular. The shape of shared nucleus of dilator muscles and pigment epitheliums changed to lobular, and the dilator muscle layer was thinner than in the control.. The high affinity of α-blockers for α(1)-adrenoreceptors is important in the analysis of the mechanism of IFIS. However, IFIS should not be attributed to long-term binding with receptors alone; the drug-melanin interaction causing dilator muscle atrophy is probably the other important factor in the mechanism of IFIS.

Topics: Adrenergic alpha-1 Receptor Agonists; Adrenergic alpha-1 Receptor Antagonists; Animals; Dose-Response Relationship, Drug; Indoles; Intraoperative Complications; Iris; Iris Diseases; Male; Melanins; Muscle Contraction; Muscle Hypotonia; Muscle, Smooth; Phenylephrine; Pigment Epithelium of Eye; Rabbits; Receptors, Adrenergic, alpha-1; Sulfonamides; Syndrome; Tamsulosin