Purchase this article with an account.
G Richter, UP Genth; Current Model of Waterjet Cuts on Living Corneal Tissue . Invest. Ophthalmol. Vis. Sci. 2002;43(13):2085.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose: In the perspective of the development of waterjet based refraktive and flap producing devices, the exact understanding of the waterjet cutting mechanisms through living corneal tissue has prior importance. In this context, the present study was performed to propose a model which is in consideration of all recently available knowledge able to describe the mechanisms of the corneal waterjet cut in their detailed complexity. Methods: Besides complementary laboratory studies the starting point of considerations were the results of last year’s presented investigation of corneal waterjet cuts on live rabbits using Medjet's Waterjet Microkeratome. We enrolled 50 New Zealand White Rabbits into the study. The flap producing cuts were performed on left eyes only using different jet parameter settings to evaluate their influence on erosion. We analyzed the erosion related corneal thickness change using pachymetrie measurements in five locations before surgery and during a 28-day follow up. Complementary UBM examinations were performed four weeks after surgery. The created Waterjet cutting model is wide ranged proven by the results of the rabbit trial and partial hypothetic. Results: The analysis shows that the waterjet cut through living corneal tissue is the outcome of 2 overlaying jet scans in respect to the cornea. The erosion related to the 2 resulting cuts depends on different technical cutting parameters and is especially effected by the characteristics of the jet (jet diameter, jet speed), the quality of the corneal tissue (Hydration, amount of cross links etc.) and the scan speed. The complexity of the waterjet cut is enhanced due to the fact that the jet is changing its characteristics continuously during the pathway through the corneal tissue, which explains the different cutting behavior in the area of the jet exit compared to the entrance. Conclusion: The proposal of a sophisticated waterjet cutting model is one of the most important prerequisites for a successful waterjet device development. It gives the basics for detailed technical solutions to compensate the peculiarities of the waterjet cut through corneal tissue to achieve controllable erosion in the entire area of the cut.
This PDF is available to Subscribers Only