Simplified suprachoroidal buckling: sclerotomy-free viscoelastic injection with a novel device in porcine eyes.

Abstract

PURPOSE: To evaluate the technical feasibility of a standardized, sclerotomy-free method for injecting viscoelastic material into the suprachoroidal space using a novel mechanical injector, and to evaluate an upgraded injector version in an ex vivo porcine model. METHODS: This laboratory investigation was conducted at a central medical research center using thirteen freshly enucleated pig eyes obtained from a local farm. All eyes underwent a 360-degree peritomy and were fixed to a Styrofoam platform. In cohort 1 (n = 5), a custom mechanical injector (Supra SEG) with a 30-gauge needle and selectable penetration depths (0.7 mm and 0.9 mm) was used to inject saline or viscoelastic materials (Biolon Prime, Healon 5 Pro, and Healon EndoCoat) into the suprachoroidal space (SCS). In cohort 2 (n = 8), an upgraded injector (27-gauge needle and larger-diameter tubing) was evaluated using the 0.9 mm depth. Ultrasound biomicroscopy (UBM) was performed before and after each injection to confirm SCS localization. The primary outcome was successful UBM-verified delivery into the SCS. RESULTS: In cohort 1, injections at 0.7 mm were unsuccessful in all attempts, whereas 0.9 mm enabled correct SCS delivery in all eyes. In cohort 2, successful UBM-confirmed suprachoroidal delivery was achieved in all eight eyes across multiple viscoelastic materials, including sequential and repeat injections that produced a larger, merged suprachoroidal bleb. UBM demonstrated characteristic echogenic appearances for each material. Injection resistance in cohort 2 was consistently mild to moderate. CONCLUSION: A sclerotomy-free, image-guided, tangential suprachoroidal injection technique using a purpose-built injector is technically feasible in ex vivo porcine eyes. Because this post-mortem model cannot adequately assess hemorrhagic complications, procedural safety and clinical performance require further in vivo evaluation.