Early Detection of Corneal Graft Rejection
American Journal of Ophthalmology, June 2017
Early detection of graft rejection is crucial to the success of corneal transplantation. Abou Shousha et al. assessed the utility of the endothelium/Descemet membrane (En/DM) complex in the diagnosis of corneal graft rejection and found it highly effective for this purpose.
Their diagnostic reliability study included 139 eyes imaged in vivo by high-definition optical coherence tomography (OCT). Ninety-six grafts had been used in penetrating keratoplasty or Descemet stripping automated endothelial keratoplasty (40 were clear, 23 actively rejecting, 24 rejected, and 9 were nonimmunologic failed grafts). The other 43 grafts served as healthy age-matched controls. The images obtained by OCT were used to describe the En/DM complex and to measure central corneal thickness (CCT) and central En/DM thickness (DMT). The En/DM rejection index (DRI) was computed to determine En/DM thickening relative to the entire cornea.
DMT and DRI were significantly greater in the actively rejecting grafts than in clear and control grafts (p < .001). Rejected grafts had the highest DMT (59 mm) and DRI (2.1) of all study groups (p < .001). DMT and DRI were highly accurate for differentiating actively rejecting grafts from clear grafts (100% and 96% sensitivity, respectively; 92.5% specificity for both) and for distinguishing actively rejecting from fully rejected grafts (88% and 83% sensitivity and 91% and 83% specificity, respectively). DMT and DRI differentiated nonimmunologic failed grafts from rejected grafts with sensitivity of 100% and with specificity of 88% (DMT) and 100% (DRI). DMT correlated significantly with rejection severity (p < .001). Both DMT and DRI were superior to CCT in terms of accuracy, sensitivity, and specificity.
Although current techniques to detect failure of corneal grafts may provide valuable clinical information, their ability to identify mild rejection and predict graft survival is limited. The authors concluded that DMT and DRI have excellent accuracy, sensitivity, and specificity for detecting the immunologic status of corneal grafts.
The original article can be found here.