Differential effects of primary disease and corneal vascularisation on corneal transplant rejection and survival

• Published in: British journal of ophthalmology Vol. 104; no. 5; p. 729
• Main Authors: Sibley, Daniel, Hopkinson, Cathy L, Tuft, Stephen J, Kaye, Stephen B, Larkin, Daniel F P
• Format: Journal Article
• Language: English
• Published: England 01-05-2020
• Subjects: Adult; Aged; Cornea - pathology; Cornea - surgery; Corneal Transplantation - adverse effects; Female; Follow-Up Studies; Graft Rejection - diagnosis; Graft Survival; Humans; Keratoconus - surgery; Male; Middle Aged; Registries; Retrospective Studies; Risk Factors; Visual Acuity; neovascularisation; cornea; eye (tissue) banking
• ISSN: 1468-2079
• DOI: 10.1136/bjophthalmol-2019-314200

To investigate the relative risk of pretransplant corneal vascularisation on rate of rejection and graft failure within 5 years of surgery when categorised by indication for transplantation.We analysed all adults recorded in the UK transplant registry who had a first cornea transplant for keratoconus (KC), pseudophakic bullous keratopathy (PBK) or previous infection (viral/bacterial/fungal/protozoan) between 1999 and 2017. We analysed the number of quadrants of the recipient cornea vascularised before transplant and type of vascularisation, the interval post-transplant to rejection, if any, and the outcome at 5 years post-transplant. Risk factors for rejection and transplant failure were modelled by multivariable risk-adjusted Cox regression.
Corneal vascularisation was recorded in 10%, 25% and 67% of patients with KC, PBK and infection, respectively. Individuals with PBK had an increased hazard of transplant rejection only when there were more than two quadrants of vascularisation (HR 1.5, p=0.004) when either superficial and/or deep vascularisation was present (HR 1.3 and 1.4, respectively, p=0.004). Individuals who had a transplant for previous infection had an increased hazard of rejection with four quadrants of vascularisation (HR 1.6, p=0.003). There was no risk-adjusted increase in transplant failure associated with vascularisation in any group. There was weak evidence of reduction in risk of rejection and/or failure associated with lamellar compared with penetrating transplantation in KC and PBK in vascularised recipient corneas.
Vascularisation is a risk factor for corneal allograft rejection within 5 years. The indication for transplantation has a clinically significant effect on the magnitude of this risk.