Abstract
Purpose: :
To evaluate plasma knife (FUGO blade)-assisted in-situ excision of donor corneas for tissue safety and quality before and after corneal transplantation surgery in comparison with conventional manual technique of donor cornea retrieval.
Methods: :
Potential donors were screened and those found to have eyes suitable for corneal transplantation were selected for the study with the consent of their relatives. The corneas of each donor were harvested by in-situ excision using either plasma knife-assisted extraction (Group 1) or conventional manual technique (Group 2) for right or left eye by random allocation for both type and sequence of technique. Harvested corneas were placed in vials containing McCarey Kaufman corneal storage medium and transported to the eye bank in an insulated container with ice packs. The donor corneas were assessed for microbial contamination, clinical grade by slit lamp evaluation and endothelial cell density both at the time of extraction and in vivo on follow up after transplantation.
Results: :
A total of 15 donors were included. On random allocation, Group 1 and 2 included 15 and 13 eyes respectively as there were two single eyed donors. The study design ensured that both groups were comparable with respect to donor age (median 50 years) and death preservation time (4.7 + 1.39hrs and 4.75 + 1.48 hrs). The other parameters studied before transplantation i.e. pre-operative endothelial count (2181 + 286.3 and 2103 + 186.8; p=0.41), microbiological contamination tested at baseline (73% and 77%; p=0.84) and tested at the time of transplantation (60% and 54%; p=1.0) were similar. Graft characteristics in recipients after a week and 3 months were similar for groups 1 and 2 respectively i.e. endothelial cell density (1821, 1800; p=0.98 and 1633. 1639; p= 0.61), central corneal thickness (583 + 26.3, 577 + 21.9; p=0.52 and 561 + 30.1, 587 + 54.2; p=0.24 ), graft clarity (p=0.08 and 0.69) and best spectacle corrected visual acuity (p=0.50 and 0.67). One case of graft infection was seen in the conventional extraction group, the difference was not statistically significant (p=0.46)
Conclusions: :
Plasma knife is equally safe and effective compared to conventional manual technique for donor cornea retrievalby in situ excision in relation to quality of tissue for corneal transplantation.
Keywords: cornea: clinical science • cornea: endothelium • transplantation