Intraoperative floppy iris syndrome might be more common among men and those with taking certain medications, most prominently tamsulosin. Photo: Flomax. Click image to enlarge.

Adequate pupil dilation during cataract surgery is critical in reducing the risk of intraoperative complications and optimizing surgical outcomes. One condition that’s known to complicate phaco procedures is intraoperative floppy iris syndrome (IFIS), which can easily turn a vision-saving surgery into one that’s visually devastating.

One or all of the following may occur intraoperatively in patients with IFIS, depending on the condition’s severity:

1. A floppy iris stroma, which billows and ripples responding to phacoemulsification fluid currents.

2. An iris stroma prone to prolapse through the incisions.

3. Progressive intraoperative miosis independent of the use of mydriatic agents.

Using the above, IFIS cases are characterized as mild (A), moderate (A and B or A and C) or severe (all three).

In 2011, a meta-analysis investigating predisposing factors for IFIS found that these include tamsulosin, other a1-ARAs (e.g., alfuzosin, terazosin, doxazosin, prazosin), hypertension and diabetes. Researchers recently decided to follow-up on these findings with a systematic review and meta-analysis on studies from the last decade. They analyzed 38 articles published in Medline and Cochrane Library databases and reported the incidence of floppy iris, iris hypotony, iris tear or iris prolapse. For the purposes of this study, IFIS development was characterized as the presence of any of the three signs above during cataract surgery.

The factors found to predispose patients to IFIS were male gender (odds ratio (OR)=4.25), hypertension (OR=1.55), tamsulosin (OR=31.06), finasteride (OR=4.60), benzodiazepines (OR=2.88) and antipsychotics intake (OR=6.91). Additionally, patients with a decreased dilated pupil diameter preoperatively also had a higher risk of IFIS development (weighted mean difference=-0.93).

“Despite other emerging factors predisposing to IFIS development, tamsulosin remains to date, the major predisposing IFIS factor,” the researchers noted in their paper on the study, published in the Journal of Cataract and Refractive Surgery. “This strong correlation is explained by the high affinity of tamsulosin with the a1A and a1D adrenergic receptors, which is 10-times higher than any other a1-ARAs that could also be the explanation as to why other a1-ARAs were not significantly correlated with IFIS development in our study,” they explained.

One potential prophylactic measure to prevent IFIS that was evaluated in several articles in the databases was the preoperative use of intracameral epinephrine. However, it did not reach statistical significance (OR=0.29).

The researchers recommend completing a risk assessment prior to cataract surgery to determine if a patient has factors predisposing them to IFIS. “Identifying these high-risk patients and employing the required preventive measures significantly reduce the complication rates down to baseline levels,” they concluded.

Christou CD, Esagian SM, Ziakas N, et al. Factors predisposing to intraoperative floppy iris syndrome (IFIS): An updated systematic review and meta-analysis. J Cataract Refract Surg. July 20, 2022. [Epub ahead of print].