Abstract
Abstract: :
Purpose:Tissue adhesive has been cited to have a host of tissue grafting uses in ophthalmology. This is the first study to determine the feasibility of using fibrin glue (Tisseel) to secure small 1.0 mm conjunctival limbal autograft buttons in a rabbit model of stem cell deficiency. Methods:Following topical tetracaine, the corneal epithelium of 10 left rabbit eyes was completely removed by mechanically scraping with a 64 Beaver Blade. A 360–degree peritomy was then performed, recessing the conjunctiva 10mm from the limbus. Donor cells were obtained from the right eyes of these rabbits. A 1.0mm skin punch biopsy was used to harvest a lamellar graft from the limbus using .12 forceps and a #66 Beaver blade. Next, the harvested biopsies were affixed to the recipient cornea at the 12:00, 3:00, 9:00, and paracentral corneal positions using Tisseel glue injected through a double–chambered syringe. A variety of techniques were used in the attempt to maximize the delivery and adhesive capacity of the fibrin–thrombin complex. A contact lens was then placed over the cornea to help maintain the grafts. Post–operative evaluation included assessment of contact lens presence, location and number of remaining grafts, the size and location of the epithelial defect and presence of epithelial migration from the grafts. Results:Thirty–four grafts were affixed to 10 recipient de–epithelialized corneas with Tisseel. At post–op day 1, 10 grafts remained (five eyes). At post–op day 3, four grafts remained affixed (two eyes). A total of 3 grafts remained at day 6 (one eye). The central button did not remain affixed in any of these rabbits. The pattern of epithelialization seemed to be a wave front from the limbus centrally. None of the grafts demonstrated an epithelial front emanating from them. The contact lens was found in place on day 1 in 7 eyes. Finally, the use of Tisseal required some manipulation to achieve maximal adhesion. Conclusions:The 1.0mm grafts in Tisseal do not appear to retain the capacity to promote epithelialization. Furthermore, Tisseel does not appear to be a feasible method for affixing 1.0 mm lamellar limbal grafts to a debrided recipient cornea as only three of thirty–four grafts remain attached at day 6 post operatively. This study suggests that surface area may be a critical variable in the effectiveness of Tisseel as biological glue for ophthalmic use. Further study is warranted to evaluate the role of donor size, and harvesting technique in the efficacy of Tisseel in stem cell transplant surgery.
Keywords: cornea: epithelium • transplantation