Trabeculectomy More Effective Than Medication at Reducing Vision Field Loss in Glaucoma

Patients with advanced glaucoma were found to have better outcomes when receiving a trabeculectomy as their first-line treatment compared with those who used medical treatment, as the rate of visual field (VF) loss was faster in the latter, according to a study in Ophthalmology.¹

Glaucoma is a disease that affects the optic nerve, causing the loss of VF and potentially blindness if not treated effectively by lowering intraocular pressure (IOP) in the eye.² Although no cure has been found, slowing the loss of VF can help maintain a patient’s quality of life (QOL), which is the primary goal of treatment. This analysis used data from the Treatment of Advanced Glaucoma Study (TAGS) to evaluate the differences in the rate of change in VF and QOL between the medical and surgical treatment arms.¹ The specific surgical intervention was trabulectomy, an operation that creates a new pathway for fluid in the eye to drain from by creating a flap in the white of the eye underneath the upper eyelid.³

The TAGS recruited patients who had been diagnosed with advanced glaucoma in at least 1 eye recently, with patients randomly assigned to receive trabeculectomy or medication as their first treatment.¹ The primary outcome was the QOL of patients in each group measured by the 25-item Visual Function Questionnaire (VFQ-25). Patients completed the VFQ-25 at baseline and months 4, 12, 24, 36, 48, and 60. IOP, visual acuity, and VF testing were measured during the clinical effectiveness analyses at baseline and months 4, 12, 24, and 60. The index eye was either the only eye that had disease or the eye with less severe disease. Patients needed to have at least 2 VFQ-25 questionnaire results to be included.

There were 442 eyes included in the main analysis, split nearly evenly between the right (211) and left (231) eyes, with the better eye included for all participants.

The trabeculectomy arm was found to have a rate of progression of VF that was 0.37 dB/year slower compared with the other arm over 5 years. The rate of change in the VFQ-25 composite score was also slower in the trabeculectomy, but this was not significant.

There was a positive correlation between the VFQ-25 score baselines and rates of change with the estimate baselines and rates of change in the index eye VF and binocular integrated VF (BI-VF), with the correlation being stronger for the BI-VF than the index eye VF. There was also a significant correlation between the BI-VF and the index eye VF for both estimated baselines and rates of change.

The difference in the rate of progression of VF between the treatment arms was significant in the subscale model, and there was no difference in the estimated baseline and rates of change for the BI-VF or any subscales.

A limitation to this study was that informative censoring from patients who had stopped driving was not considered for this analysis, which the authors identified as a target for future research.

“Trabeculectomy was more effective than drops in preserving VF and should be considered as a first treatment in patients with advanced glaucoma,” the authors concluded.

References

1. Montesano G, Ometto G, Cheloni R, et al; TAGS Study Group. Longitudinal visual field and quality of life change in the treatment for advanced glaucoma study. Ophthalmology. Published online April 24, 2026. doi:10.1016/j.ophtha.2026.04.020
2. Glaucoma. Cleveland Clinic. Updated November 12, 2024. Accessed April 27, 2026. https://my.clevelandclinic.org/health/diseases/4212-glaucoma
3. Johnson TV III. Trabulectomy. Hopkins Medicine. Accessed April 28, 2026. https://www.hopkinsmedicine.org/health/wellness-and-prevention/trabeculectomy