Abstract
Purpose: :
To evaluate outcomes of a single surgeon consecutive series of PKP at McGill University
Methods: :
This was a retrospective analysis of a consecutive series of PKP at McGill University from 2005 to 2009. Follow-up (F/U) was calculated from time of surgery to date of last visit or when graft failure, defined as non-reversible diffuse corneal edema, occurred. Outcome measures were graft survival, post-op best vision (BCVA), and complications such as infectious keratitis, glaucoma and wound dehiscence. Predictor variables were PKP indication, donor’s age and endothelial cell count (ECC), patient’s lens status, and time from donor’s death to graft preservation and from preservation to surgery.
Results: :
There were 128 eyes of 119 patients (62 males and 57 females). Mean age was 66 y.o. (15 to 87), and mean F/U was 26 months (2 to 58). 84% of cases had F/U of 1 year or more. 18 eyes had keratoconus (KC), 89 had corneal edema, 13 had a corneal scar, 6 had a stromal dystrophy, and 2 had tectonic PKP. KC patients had the highest graft survival probability (94%), followed by corneal scar (85%), stromal dystrophy (83%), corneal edema (79%), and tectonic cases (50%). KC cases had the best visual outcomes, with 44% having a final Snellen BCVA of 20/40 or better, and 50% between 20/50 to 20/200. There was no difference in terms of donor ECC, donor age, death to preservation time, and preservation to surgery time between failed and clear grafts. We found a relationship between patient’s lens status and final graft status (p <0.05). Specifically, failed grafts had a higher number of cases with ACIOL compared to clear grafts. The most common complication post-op in all groups was elevated intraocular pressure (IOP) (53%), which was controlled with drops in 91% of cases. There was one case of expulsive choroidal hemorrhage and all other complications were rare (<2%).
Conclusions: :
PKP is an effective and safe long-term treatment for corneal pathology. Overall survival depends on various factors, such as surgical indication and lens status, which can be used to predict outcome. Visual outcome is variable; there is likely a role of PKP indication and other associated eye diseases in determining final results. Patients need frequent IOP monitoring. Future directions are to compare long-term survival of endothelial keratoplasty with PKP in select cases.
Keywords: cornea: clinical science • transplantation