Surgical outcomes of trabeculectomy augmented with sub-Tenon injected mitomycin C

Recently, trabeculectomy with mitomycin C (MMC) where MMC is applied by injection into the Tenon layer has attracted close attention. However, the data on efficacy and safety of this technique is still limited and more clinical studies are needed. Therefore, the work is aimed at comprehensive evaluation of the effectiveness of trabeculectomy using MMC applied by intra-Tenon injection.

A set of 50 eyes in 50 patients underwent trabeculectomy using MMC at concentration of 0.4 mg/ml in a total volume of 0.05 ml. The primary end point was to control intraocular pressure (IOP) on postoperative days 1, 8, 30 and 90 and subsequently at 6 and 12 months after surgery. The secondary end point was to evaluate the changes in various corneal parameters prior to and 90 days after surgical procedure.

The mean preoperative IOP was 32.34 ± 9.45 mmHg. After surgery, the mean IOP significantly decreased to 17.52 ± 4.58 mmHg at the 90-day follow-up, and to 18.14 ± 3.74 and 19.30 ± 3.82 mmHg at 6 and 12 months after the procedure, respectively. The mean BCVA values remained unchanged compared to baseline (0.77 ± 0.23) to the 90-day follow-up (0.80 ± 0.23).  The mean number of anti-glaucoma medications significantly reduced from 3.50 ± 0.74 to 0.58 ± 1.03 postoperatively. Similarly, the mean corneal hysteresis and ACD of the eye as well as CECD were significantly changed postoperatively.

Trabeculectomy using MMC applied by injection is a safe and effective surgical method for the treatment of primary and secondary forms of open-angle glaucoma. It has a significant hypotonising effect and allows a complete discontinuation of antiglaucoma drugs (Tab. 3, Fig. 3, Ref. 58).