The low-risk, low-reward procedures collectively known as minimally invasive glaucoma surgery (MIGS) are growing in popularity and provide an alternative to traditional incisional techniques. A new study looking into the 12-month outcomes of stand-alone ab interno trabeculotomy found that this procedure significantly lowered both IOP and medication scores in patients with glaucoma, although almost one-quarter needed an additional surgery. The researchers noted that the surgical success rate was significantly higher in eyes with pseudoexfoliative (PXF) glaucoma compared with open-angle glaucoma.

A team from Japan enrolled 34 eyes of 29 patients with either POAG (16) or PXF (18).

The investigators noted statistically significant decreases in IOP and medication scores from baseline through all follow-up periods. Baseline IOP was 25.6 and decreased to 15.6mm Hg at six months and 18.8mm Hg at 12 months. The medication score, which was 4.4 at the onset of the study, fell to 1.9 at one month and 2.9 at 12 months. Surgical success rates were approximately 97%, 77% and 44% at three, six and 12 months, respectively.

Eight eyes (24%) needed additional glaucoma surgery, which the investigators attributed to disease severity. These included four cases of POAG and four cases of PXF, with a baseline IOP of 27.4mm Hg and medication score of 4.6. Even though several of these severe cases resulted in additional procedures, the investigators performed filtration surgery with a non-damaged conjunctiva postoperatively.

The study also suggested the type of glaucoma, specifically POAG, was strongly linked to surgical failure, while participants with PEG had far better outcomes.

Omoto T, Sugiura A, Fujishiro T, et al. Twelve-month surgical outcome and prognostic factors of stand-alone ab interno trabeculotomy in Japanese patients with open-angle glaucoma. PLoS One. 2021;16(1):e0245015.