Fluorouracil Filtering Surgery Study (FFSS)

Fluorouracil Filtering Surgery Study (FFSS)

PURPOSE:

–       To determine if subconjunctival injections of 5-fluorouracil (5-FU) given postop after glaucoma filtering surgery boost the success rate in patients at high risk for failure

STUDY DESIGN:

–       Randomized, controlled clinical trial

–       213 patients enrolled- 162 aphakic, 51 with history of filtering surgery- all with IOP greater than 21 mm Hg on maximal tolerated therapy

–       Evaluated success of standard glaucoma filtering vs standard surgery with adjunctive 5-FU injections

–       Adverse ocular and systemic effects of 5-FU injections assessed in terms of frequency and severity and were monitored for treatment complications

–       Postoperatively randomized to standard care or 5-FU injections

–       For 5-FU group, 5 mg of 5-FU injected twice daily on 1^st to 7^th postop days and daily on 8^th to 14^th postop days

–       Standard postop follow up for 5 years

RESULTS:

–       Success = no need for additional surgery to control IOP; no recorded IOP > 21 at/after 1-year follow-up

–       5-FU led to improved IOP control/success rates during all follow-up periods (48 % for 5-FU vs 21% for standard group at 5 years)

–       Patients noted to have decreased loss of VA loss if IOP remained controlled compared to uncontrolled IOP

–       No difference in change in VF sensitivity between two groups

–       Visual field loss related to high IOP- patients requiring repeat operation showed more VF loss

–       VA and VF loss observed in both groups during the 5 years of the study

–       Factors associated with success rate include preop IOP, number of conjunctival incisions during previous ocular procedures, and the time period between the study filtering surgery and previous intraocular surgery

–       5-FU group with higher rate of late-onset filtering bleb leak (9 percent vs 2 percent) and more cases of endophthalmitis (2 cases vs 1 case).

–       No other long-term adverse effects were significantly different between two groups

TEACHING POINTS:

–       5-FU injections recommended after trab in aphakic patients or in patients with a history of unsuccessful filtering surgery given lower success rates

–       Proved relationship between high preop IOP and acute postop hypotony as risk for suprachoroidal hemorrhage. Measures now in place to prevent postop hypotony if high IOP noted preop with multiple tightly tied sutures or with releasable sutures in the scleral flap to have additional control on postop IOP.

–       Given possibility of complications related to 5-FU, caution use in patients with higher success rates with filtering surgery

–       IOP control is essential to preserving visual function