Effect of collagen implants in the reduction of high astigmatism induced by penetrating keratoplasty

Purpose: To evaluate the insertion of EagleVision(R) collagen plugs as spac ers between corneal relaxing incisions to correct significant residual asti gmatism after penetrating keratoplasty (PKP). Setting: Ambulatory Clinic of the Department of Ophthalmology, Rhode Island Hospital, and Rhode Island Eye institute, Providence, Rhode Island, USA. Methods: This study comprised 8 patients meeting the following criteria: ha d previous PKP, had at least 5.0 diopters of residual keratometric astigmat ism with all the sutures removed, were free from eye infection, and were at least 21 years old. Ali 8 patients had unilateral high astigmatism after P KP. Four eyes were randomly assigned to the control group of astigmatic ker atectomy (AK) incisions without the collagen implants and 4 eyes to the exp erimental group of AK incisions with collagen implants. Results: Best corrected visual acuity 1 day, 3 weeks, and 1, 2, and 6 month s after AK showed decreased astigmatism in all the patients who had the rel axing incisions. The amount of astigmatism was lower in patients who receiv ed AK incisions with collagen implants (P < .28). Minimal adverse effects w ere noted. Conclusion: Implanting a biocompatible material into AK incisions to correc t post-PKP astigmatism appears to be safe and may enhance astigmatic correc tion. (C) 1999 ASCRS and ESCRS.