Abstract
Abstract: :
Purpose: In the perspective of the development of waterjet based refraktive and flap producing devices, the recent study was performed to evaluate potential safety hazards of waterjet cuts through living corneal tissue and possible healing complications. Methods: The waterjet cuts were performed using the Lab Setup of Medjet's Waterjet Microkeratome, which was adapted to the special needs for surgery on live rabbits. 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 its influence on erosion. We analyzed the erosion related corneal thickness change using pachymetry measurements in five locations before surgery during a 28-day follow up. Complementary UBM and slit lamp examinations were performed to document the morphological outcome and to study cutting failures and healing complications. Results: 38 of the 50 enrolled rabbits reached the end of the follow up. 30 of those 38 rabbits showed good cutting result and could be included in the corneal thickness comparison. The remaining 8 rabbits were excluded from the statistics because of significant complications during the cut or the healing. According to the protocol, we had to euthanice 12 of the 50 rabbits as a result of major complications. Observed cutting errors where: corneal perforation and flap laceration related to hyper energetic jets or inappropriate high IOP, corneal aeration and hydration, inhomogeneous erosion (striations), short cuts, cuts with irregular flap thickness, irregular boundary or large gutter, epithelial ingrowth and corneal infections. Conclusions: The presented safety hazard analysis summarizes waterjet cut related problems that occurred in the experimental stage of the product development. Based on the gained knowledge the final product has to be optimized in technology and procedure.
Keywords: refractive surgery: complications • refractive surgery: other technologies • wound healing