IFIS severity may be lessened by washout period before cataract surgery

Key Points

"IFIS during cataract surgery was first described in 2005 in patients treated with tamsulosin for BPH," Dr. Calsina noted. "IFIS typically presents with progressive pupillary constriction during hydrodissection and phacoemulsification, marked propensity for the iris to prolapse to the phaco and side-port incisions, and a floppy iris that billows in response to normal irrigation currents in the anterior chamber."

Tamsulosin, a systemic α-1 blocker used to treat the urinary symptoms of BPH, works by competitively inhibiting the sympathetic autonomic nervous system, resulting in relaxation of the smooth muscle, explained Dr. Calsina, a resident in ophthalmology, Esperança Hospital, Institut Municipal d'Assistència Sanitaria, Barcelona, Spain.

Two washout periods

In light of the adverse effect of tamsulosin during cataract surgery, Dr. Calsina and colleagues undertook a study to compare IFIS in the eyes of six men who underwent surgery after a 15-day or a 30-day washout period of the drug. One eye of each patient underwent surgery after a 15-day washout period, and the fellow eye underwent surgery after a 30-day washout period. The investigators also sought to determine how the aforementioned viscoelastic worked in the eyes of another six men with IFIS following a 15-day washout period of tamsulosin.

The patients all had been treated with tamsulosin for more than 5 months. Patients were excluded if they had advanced diabetic retinopathy, pseudoexfoliation, uveitis, or treatment with topical pilocarpine. The fluidics were set at low rates (aspiration, 25 ml/min or less; vacuum setting, 250 mm Hg or less).

The investigators evaluated several intraoperative facts: mydriasis preoperatively, mydriasis after irrigation and aspiration, iris and pupil reaction, surgical maneuvers needed, and intraoperative complications.

In the eyes with the 15-day washout period, the preoperative dilation was 8 mm in three eyes, 7 mm in one eye, and 6.5 mm in one eye with phenylephrine and tropicamide applied three times. Pupil constriction was seen in all cases, with 6- to 4-mm pupils after irrigation and aspiration. Two cases had IFIS, and three had miosis, minimal fluctuation, and no iris prolapse. No use of retractors was required, and no complications developed, Dr. Calsina reported.

In the eyes with the 30-day washout period, the preoperative dilation was 8 mm in three eyes, 6 mm in one eye, and 6.5 mm in one eye, with phenylephrine and tropicamide applied three times. One patient had IFIS, and two had miosis, minimal fluctuation, and no iris prolapse. One did not develop IFIS, and one had minimal fluctuation only.