The effects of tamsulosin and alfuzosin on iris morphology: an ultrasound biomicroscopic comparison

Risk of intraoperative floppy iris syndrome among selective alpha-1 blockers—A consistency model of 6,488 cases

Selective α1-blockers are commonly administered to patients with lower urinary tract syndrome and benign prostatic hyperplasia, but may increase the risk of intraoperative floppy iris syndrome (IFIS). The purpose of this study aimed to clarify the risk of IFIS among various selective α1-blockers. Four databases were searched for prospective studies comparing alpha-1-antagonists. Data were pooled using the consistency model, and used risk ratio (RR) and mean difference (MD) for IFIS and pupil diameter, respectively. This study finally included 25 prospective comparative studies. Based on 51 direct comparisons with 6488 cases, risks of IFIS in patients who received tamsulosin [RR, 13.85; 95% confidence interval (CI): 7.34 to 26.11], terazosin (RR, 8.94; 95% CI 2.88 to 27.74), alfuzosin (RR, 7.73; 95% CI: 3.05 to 19.62), and doxazosin (RR, 3.88; 95% CI: 1.13 to 13.28) were significantly higher than those did not receive α1-antagonists. Based on 11 direct comparisons with 564 cases, as compared to no α1-antagonists, patients who received tamsulosin (MD, −0.36; 95% CI: −0.71 to −0.01) and alfuzosin (MD, −0.34; 95% CI: −0.62 to −0.07) showed smaller pupil diameter under mesopic light levels, while those received silodosin did not show significantly smaller mesopic pupil diameter than people without α1-antagonists. IFIS seems to be inevitable with the usage of α1-antagonists, and tamsulosin needs to be cautious due to the significantly higher risk of severe IFIS. With regard to silodosin, there is no strong evidence to support the uses of italthough it does not significantly decrease mesopic pupil diameter.

Intraoperative Floppy Iris Syndrome Induced by Tamsulosin: The Risk and Preventive Strategies

Tamsulosin is an antagonist of a subtype-specific alpha-1A- and alpha-1D-adrenoceptor (AR) that is expressed in the prostate gland, urethra, and bladder. Several reports have shown a possible relationship between ophthalmologic adverse effects and the use of alpha-1-receptor medicines, including tamsulosin. This descriptive review evaluates the intraoperative floppy iris syndrome (IFIS) associated with tamsulosin. A search of the Medline and PubMed databases was conducted to identify control trials, case reports, and observational examinations published in English. The publication dates were restricted (January 1, 2000, to January 1, 2020). Keywords (tamsulosin, alpha-blocker, ocular, eye, adverse reaction, and IFIS) were used in the searches. The searches identified 66 studies including in vitro or in vivo studies, trials, and observational studies. Twenty-two (33.33%) studies were articles citing tamsulosin and IFIS as having confirmed potential risk to ocular safety. The results of this review, including a comprehensive summary of published research on tamsulosin use in different populations, have identified several articles showing associations between tamsulosin and IFIS that merit further investigation. Suspending of potential causative pharmacological treatment of IFIS before ocular surgery including tamsulosin, proper identification of at-risk patients, preoperative prophylaxis treatments, and surgical technique modifications clearly can mitigate the anticipated risk of IFIS induced by tamsulosin.

Floppy iris syndrome and cataract surgery

PURPOSE OF REVIEW

Intraoperative floppy iris syndrome (IFIS) occurs in 2% of cataract surgeries and is associated with an increased risk of surgical complications. These complications can be avoided when high-risk patients are identified by preoperative screening and appropriate measures are used intraoperatively. The purpose of this article is to review emerging risk factors for IFIS and to summarize management strategies used in IFIS.

RECENT FINDINGS

Although α1-antagonists in general, and tamsulosin (Flomax, Jalyn) in particular, have long been associated with IFIS, recent studies have more firmly demonstrated the elevated risk of IFIS attributed to tamsulosin. This resulted in a revision of the American Society of Cataract and Refractive Surgery/American Academy of Ophthalmology guidelines on IFIS. Our understanding of additional medications and medical conditions involved in IFIS is also evolving, including an appreciation that women are also susceptible to IFIS. New modifications of techniques used in the intraoperative management of IFIS are also discussed.

SUMMARY

Preoperative screening should include both men and women. Current or prior use of α1-antagonists and antipsychotics should be documented, along with hypertension. Surgeons should be prepared to employ a range of perioperative interventions in a graded response to IFIS of different severities.