Citation Information :
Vander Zee BL, Wilson C, Berdahl JP, Terveen D, Ferguson TJ. Superonasal vs Inferonasal Subconjunctival Gel Stent Placement in Patients with Glaucoma. J Curr Glaucoma Pract 2024; 18 (2):63-67.
Aim and background: To compare the safety and efficacy of subconjunctival gel stent implantation in the superonasal (SN) vs inferonasal (IN) quadrants in the treatment of glaucoma.
Materials and methods: Patients with a history of IN (n = 29) or SN, (n = 96) gel stent placement with ≥3 months of follow-up were included. Intraocular pressure (IOP) and the number of glaucoma medications were collected preoperatively and postoperatively at months 1, 3, 6, and 12. Safety measures included the number of bleb needlings, complication rate, and additional surgeries.
Results: Mean baseline IOP was 32.4 ± 11.7 mm Hg in the IN group and 21.6 ± 9.2 mm Hg in the SN group (p < 0.01). IOP was similar between groups at 3 months (IN = 15.8, SN = 15.6, p = 0.45), 6 months (IN = 17.4, SN = 15, p = 0.13), and 12 months (IN = 17.9, SN = 14.7, p = 0.15) follow-up. The number of glaucoma medications was also similar at 3 months (p = 0.31), 6 months (p = 0.24), and 12 months (p = 0.39) follow-up. Bleb needling rates were similar with 51.7% (15/29) in the IN group vs 42.7% (41/96) in the SN group (p = 0.39) and subjects requiring further surgery were 17.2% (5/29) in the IN group vs 24.0% (23/96) in the SN group (p = 0.45).
Conclusion: Both IN and SN subconjunctival gel stent placements provide favorable safety and efficacy when treating open-angle glaucoma, with a meaningful decrease in medication use and IOP.
Clinical significance: Implantation of the subconjunctival gel stent in the IN quadrant is an effective and safe alternative to superior implantation in refractory glaucoma.
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