Floppy iris syndrome not necessarily related to alpha-blockers, study shows

LONDON — Intraoperative floppy iris syndrome is not always associated with the use of alpha-blockers such as tamsulosin, according to a study.

"Our results show that not all the patients who develop intraoperative floppy iris syndrome (IFIS) during cataract surgery are on alpha-blockers, and that, conversely, as many as 60% of the patients who are on alpha-blockers don't develop a floppy iris," said Aditi Molha, MD, at the meeting of the United Kingdom and Ireland Society of Cataract and Refractive Surgeons, held in conjunction with the European Society of Cataract and Refractive Surgeons meeting here.

IFIS was described by David Chang, MD, and John Campbell, MD. It is characterized by a tendency of the iris to prolapse through the cataract incision, and it is associated with poor preoperative pupil dilation and progressive intraoperative miosis. In their study on 1,600 patients, Drs. Chang and Campbell said they found "overwhelming evidence" that IFIS is caused by alpha-blockers, the most popular of which is Flomax (tamsulosin, Boehringer Ingelheim).

Dr. Molha and coworkers further investigated the incidence of IFIS by surveying their colleagues.

"At the Huddersfield Royal Infirmary, we collected data through a questionnaire sent to cataract surgeons. They did not know that we were investigating IFIS, but answered a series of questions concerning the behavior of the iris and pupil during each of their cataract procedures. The answers gave us the opportunity to evaluate a total of 151 patients, of whom 12 (8%) were on alpha-blockers," Dr. Molha explained.

In this series of patients, poor pupil dilation occurred in eight patients (5%), of whom one was taking an alpha-blocker. Intraoperative pupil constriction was seen in 11 patients (7%), three of whom were taking an alpha-blocker. A loss of iris tone was seen in 14 patients (9%), of whom five were on alpha-blockers. And iris prolapse occurred in 11 patients (7%), of whom four were on alpha-blockers.

"In conclusion, according to the results of our study, IFIS and alpha-blocker use can be associated, but not invariably so. We would not recommend discontinuing the use of these medications prior to surgery, as this might cause significant symptoms to the patients without any real benefit for the surgery," Dr. Molha said.

Surgeons, she added, should not be unduly alarmed if patients are taking alpha-blockers, but, on the other hand, they should be prepared to manage IFIS in all cases.