Allogen heterotopic cartilage transplantation for primary corneal replacement in rabbit model

Background Aim of the present study was to investigate woundhealing after a llogen heterotopic cartilage transplantation in a rabbit model. Material and methods Cartilage discs were transplanted by central lamellar keratoplasty (diameter 5.0 mm) in eleven New Zealand White Rabbits. Cartila ge was harvested of the ears of rabbits at the day of transplantation. The cartilage discs 0.5-0.6 mm thick were prepared with 5.2 mm diameter and tra nsplanted within 12 hours. Fixation was performed by eight 10-0 nylon sutur es. Postoperatively, dexamethasone ointment containing gentamicin was appli ed three times a day for three weeks. Clinical course was documented by pho tographs. For histological examinations the transplanted eyes were enucleat ed after one day or three days, and after 3, 6 or 12 months. Results Allogen cartilage healed firmly in the cornea within two months. Du ring the course of observation the cartilage grafts thinned and were replac ed by normal appearing collagen fibrills. In one case neovascularisation of the cornea occurred and reached the cartilage graft, but did not invate. H istologically, in all cases no leukocytes could be seen in the cartilage or its neighbourhood. The cartilage grafts did not proliferate and remained a vascular. The intraocular structures showed no inflammatory reaction. Conclusions Allogen cartilage grafts to a clear corneal pounch do not induc e an inflammatory reaction. Therefore, autologous cartilage prepared of ear s seems to be useful biological material in ophthalmologic surgical procedu res, for example to Fill up corneal defects. To investigate if cartilage gr afts will be helpful to stop neovascularisation in keratoplasty further stu dies with vascularisized corneas are necessary.