How to Create an Immediate Self Sealing Sclerotomy for Cannula Placement in 25 Gauge Vitrectomy Using a Tunnel Incision

Abstract

Abstract: : Purpose: To describe a new approach for cannula insertion in 25 gauge transconjunctival sutureless vitrectomy to create a tunnel / self sealing incision. Design: New surgical technique Methods: The inferior rectus muscle is held with a 0.3 forceps to hold the eye stable. 25 gauge cannula placement is performed using the Alcon ® 25 gauge vitrectomy system (Forth Worth, Texas, USA). The conjunctiva is displaced superiorly using a cotton swab. A 1mm scleral tunnel is made parallel to the limbus using the 25 gauge trochar inserter with the scleral entry point 3 to 4 mm posterior to the limbus. The angle of insertion is approximately 15 – 20^o. Immediately after this the inserter is rotated, pointing to the optic nerve, and the placement is finished by pushing the cannula perpendicularly into the sclera. Results: A tunnel / self sealing incision is created by utilizing a sharp inserter to make an oblique incision in combination with grasping the inferior rectus muscle to provide ocular fixation. The muscle acts as a point for fixation for the eye, providing the necessary counterforce to avoid the rotational movement exerted by this kind of cannula placement. The biplanar incision allows self sealing scleral incisions after cannula removal Conclusions: This new approach combining muscle stabilization, oblique insertion angle, and sharp inserter allows the creation of a self sealing entry. This technique potentially minimizes the risk of hypotony and endophthalmitis due to wound leak, and may allow longer surgical times without the need for suturing.

Keywords: vitreoretinal surgery • wound healing • retina