Safety And Efficacy Of Cataract Surgery With Adjunctive 5-Fluorouracil Following Functional Glaucoma Filtration Surgery: A Short-Term Real-World Study

Cataract surgery in eyes with prior filtering surgery is associated with an increased risk of bleb fibrosis, intraocular pressure (IOP) elevation and surgical failure. Adjunctive antifibrotic therapy has been shown to decrease the risk of trabeculectomy failure in patients undergoing cataract surgery. However, evidence regarding the use of adjunctive 5-fluorouracil (5-FU) at the time of phacoemulsification in eyes with prior microshunt surgery is limited. To our knowledge it has not been specifically evaluated previously. This study aimed to evaluate the impact of phacoemulsification with adjunctive 5-FU on the survival of trabeculectomy and PreserFlo MicroShunt surgery at 12 months in a real-world clinical setting. 

This retrospective study was conducted at York Hospital Ophthalmology Department, United Kingdom. Consecutive patients with previous trabeculectomy or PreserFlo MicroShunt undergoing cataract surgery were identified through electronic medical records and followed for 12 months.

Patients with functioning filtering surgery undergoing phacoemulsification with intraocular lens implantation were included. Adjunctive subconjunctival 5-FU with or without dexamethasone was administered intraoperatively. Data collected included glaucoma diagnosis, interval between glaucoma and cataract surgery, surgical characteristics, IOP, visual acuity and treatment failure. Failure was defined as IOP >21 mmHg, need for glaucoma medications, bleb needling or further glaucoma surgery. Paired statistical analysis compared preoperative and postoperative outcomes. Subgroup analysis explored the impact of antifibrotic use, surgical interval and glaucoma subtype.

Forty-four eyes were analysed. Primary open angle glaucoma was the most common diagnosis (63.6%), followed by normal tension glaucoma (13.6%) and primary angle closure glaucoma (9.1%). Thirty-eight eyes (86.4%) had previous trabeculectomy and 6 eyes (13.6%) had PreserFlo MicroShunt surgery. Adjunctive 5-FU was used in all cases.

Mean IOP was 11.6 ± 3.9 mmHg preoperatively and remained stable at 3 months (12.5 ± 4.1 mmHg, p=0.2,) and 6 months (12.0 ± 3.2 mmHg, p=0.9). Although there was a statistical significant increase at 12 months (12.5 ± 2.7 mmHg, p=0.007), it remained well below the 21 mmHg failure threshold. Visual acuity improved from 0.32 ± 0.47 to 0.02 ± 0.11 LogMAR at 12 months (p=0.01). Treatment failure occurred in 9.1% of eyes. 

Cataract surgery with adjunctive 5-FU appears safe and effective in patients with prior filtering surgery, with high rates of trabeculectomy and microshunt survival with stable IOP control at 12 months. Significant visual improvement was achieved without compromising glaucoma outcomes. These findings support the use of intraoperative antifibrotic therapy to reduce the risk of surgical failure in this high-risk population.