Penetrating keratoplasty: a robotised cut of cornea

Abstract

After penetrating keratoplasty (PK, corneal grafting), an astigmatism occurs due to the cut and to the suture which cause deformations of the cornea. We propose to introduce new technologies into this surgery in order to limit the postoperative astigmatism and so to increase visual recovery. First of all, we study a new tool to cut cornea, a surgical waterjet. This device permits corneas to be cut at low pressure (15 to 35 bars) and with a small diameter of water (0.08 mm to 0.20 mm). Attempts have been made on freshly enucleated pig eyes, epithelium removed. The waterjet could be a useful tool for PK if it doesn't induce too much hydration of the tissue. We are working to limit this phenomenon. Another aim of our work is decreasing the postoperative astigmatism due to the suture. For that, we are thinking of limiting or avoiding this technique by robotising the cut and finding optimal shapes of cut. Different shapes of cut are studied. This is done by simulating the intraocular pressure with a height of water applying a pressure on a polyacrilamide gel. The conception of a surgical robot which would include chosen technologies is in progress.