Comparative outcomes of a newly modified trabeculectomy versus conventional trabeculectomy

This prospective comparative study evaluated the outcomes of a Newly Modified Trabeculectomy (NMT) versus conventional Trabeculectomy (trab) in patients with open-angle glaucoma, with a special interest in its usefulness for normal-tension glaucoma.

A total of 121 eyes were analyzed: 27 eyes underwent NMT and 94 eyes underwent conventional trabeculectomy. The two groups were matched for age and preoperative Intraocular Pressure (IOP). Baseline IOP was identical in both groups, with a median of 18.0 mmHg (interquartile range [IQR] 16.0–21.0), and preoperative glaucoma medication use was also comparable at 3.0 agents (IQR 2.0–4.0).

The NMT technique modifies the scleral flap step in standard trabeculectomy. During surgery, a deep scleral flap is created and removed, extending from the scleral edge beneath the superficial scleral flap to the trabecular meshwork. This deep flap is approximately 1.5 mm wide centrally and is dissected to a depth sufficient to allow visualization of the choroid. This modification is intended to enhance aqueous outflow and thereby improve IOP reduction.

Postoperative outcomes were assessed in terms of IOP, visual acuity, number of medications, complications over a 6 month follow-up. At 3 and 6 months after surgery, the NMT group showed significantly lower IOP compared with the conventional trabeculectomy group. At 6 months, the median IOP was 12.0 mmHg (10.0–15.0) in the conventional trabeculectomy group and 8.0 mmHg (7.0–10.0) in the NMT group, with a statistically significant difference (P = 0.03).

Complications observed included shallow (thin) anterior chamber and choroidal detachment. These were occurred in 3.2% of eyes in the conventional trabeculectomy group and 11.1% in the NMT group.

In conclusion, the newly modified trabeculectomy achieved significantly greater IOP reduction than conventional trabeculectomy at 3 and 6 months postoperatively, without a significant increase in complications. Therefore, NMT is considered a useful surgical option for open-angle glaucoma, particularly for normal-tension glaucoma where achieving lower target IOP is crucial.

Dr. Hyungju Park is the director of Gangnam Tokyo Eye Clinic and a glaucoma specialist. As a member of the Korean Glaucoma Society, he is dedicated to evidence‑based, patient‑centered glaucoma care. Dr. Park focuses on early diagnosis, individualized treatment strategies, and clear communication so patients understand their condition and options. He strives to provide safe, precise care that protects vision and quality of life, combining advanced diagnostic technology with thoughtful, compassionate clinical judgment.