Creation of Tri-Planar Incisions in Vitrectomy

Abstract

Background: In vitrectomy, a type of eye surgery, surgery instruments must pass through an incision in the sclera. The architecture of the incision is of great im-portance to the closure of the wound after the procedure and through that the risk for complications like hypotony and endophthalmitis. Current studies suggest that tri-planar incisions provide better sealing, however for a surgeon it is challenging to pro-duce the desired architecture easily and consistently. The objective of this study is to: “Design and verify a new, reliable and easy to use method to create tri-planar inci-sions for scleral cannulas to limit leakage after extraction of the cannula.”
Method: Analysis of the factors affecting the tri-planar incision method in terms of reliability and ease of use was performed, leading to a set of design requirements. Based on the requirements, different incision methods were explored and compared. The selected method was transformed into a functional prototype, which was subse-quently evaluated on consistency and leakage. The evaluation was done by insertion on silicone sheet, eye phantoms and ex-vivo porcine eyes. The tri-planar incision was compared in leakage to straight and oblique incisions, two other common type of ar-chitectures.
Results: The method performed using a designed device was able to create the de-sired tri-planar consistently. These incisions provided a better seal than a straight in-cision. However, for tri-planar compared to an oblique incision the test was inconclu-sive and further research is needed to distinguish between the two.
Conclusion: As tri-planar incisions can now consistently be made with the use of the new method, further research can be performed to link the number and type of com-plications, like hypotony and endophthalmitis, to the incision statistics.