Efficacy and safety of ab-externo radiofrequency sclerostomy in management of open-angle glaucoma

Purpose. To evaluate the efficacy and safety profile of an innovative ab-externo technique in the management of uncontrolled open angle glaucoma (OAG) through creating filtering tracts subconjunctivally.
Material and methods. This is a randomized clinical trial including 40 eyes (40 patients) divided into 2 equal groups, group (A), underwent ab-externo radiofrequency sclerostomy and group (B), underwent ab-externo radiofrequency sclerostomy with subconjunctival injection of mitomycin C. Intraoperative and postoperative complications, visual acuity, intraocular pressure (IOP) and bleb status were evaluated for 6 months.
Results. The mean preoperative IOP was 28 ± 3.5 mm Hg reduced to 21.9 ± 5.2 mm Hg (p = 0.001) in group (A) and was 29.4 ± 3.4 mm Hg reduced to 20.8 ± 6.3 mm Hg (p = 0.001) in group (B), 6 months postoperatively. Both groups showed a significant percent reduction of IOP 15.1 ± 17.3%, 27.1 ± 22.4% in groups (A) and (B) respectively with group (B) showing lower values on days 1, 7, 14, 30, 90 and 180 but was not statistically significant. The number of anti-glaucoma medications was significantly reduced in both groups. Heat radiation to the cornea from radiofrequency waves was obvious in early cases — 5 (25%) in group (A), and 3 (15%) in group (B) that was reversible within the first 3 months postoperatively. Shallow anterior chamber and choroidal detachment were the most encountered early postoperative complication, which all managed conservatively.
Conclusion. Ab-externo radiofrequency sclerostomy offers a promising minimally invasive, quick and simple procedure in management of early and moderate cases of OAG with effective reduction of IOP and number of glaucoma medication.

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