We thank Dr. Shoaib for his interest in our article.1 We agree that there are various causes of graft rejection and that performing an endothelial keratoplasty (EK) would not resolve the rejection. To clarify our wording for the article, patients who developed endothelial graft rejection with subsequent endothelial failure were offered EK under their penetrating keratoplasty (PK). The rejection episode was resolved at the time of the EK. There were a total of 9 patients that fulfilled this requirement and were included in the study. These patients did not have any epithelial or stromal rejection and did not have stromal opacities. We do feel that EK under PK for immunological endothelial failure is a viable treatment option that should be considered in cases where there are not any stromal opacities.

Jennifer Nottage, MD

Verinder Nirankari, MD

Eye Consultants of Maryland, Owings Mills, MD

1. Nottage JM, Nirankari VS. Endothelial keratoplasty without Descemet's stripping in eyes with previous penetrating corneal transplants. Br J Ophthalmol. 2012 Jan;96(1):24-7

Conflict of Interest:

None declared

Article "Endothelial keratoplasty without Descemet's stripping in eyes with previous penetrating corneal transplants" by Nottage JM and Nirankari VS1, is very informative and the authors deserve appreciation for their wonderful work. However one point requires discussion. Authors mentioned that endothelial keratoplasty (EK) was done either for graft rejection (n = 9) or endothelial failure (n = 24). It seems logical to replace endothelium in endothelium failure. The question is how new endothelium can correct graft rejection? Authors mention "An allograft rejection was defined as corneal clouding in association with an epithelial or endothelial rejection line, keratic precipitates and/or anterior chamber cells." Endothelial line reflecting endothelial rejection can qualify as an indication for EK but the rest of the signs can be due to rejection of the other parts of the graft. A further breakdown of the frequency of above mentioned signs of allograft rejection would have been useful. Other authors have been careful not to include the generalized graft rejection cases for EK e.g. Chen ES et al2 mentioned in their Protocal under the heading of Methods, the inclusion criteria "after penetrating keratoplasty (PK) and without significant stromal haze". Similarly Straiko et al3 described inclusion criteria "for failed PK grafts from endothelial failure with minimal stromal Opacities" and "all eyes with a prior standard PK graft that had failed because of immunologic or nonimmunologic endothelial failure". Graft rejection results from host immunologic response against foreign antigen from donor tissue. Li JY et al 4 observed that it can lead to decreased endothelial cell survival and graft failure. They reported a graft rejection rate of 7.3 % and that the greatest number of rejections occurred between postoperative months 12 and 18. An initial improvement due to healthy endothelial can be expected in all cases of EK but antigenic stimulation will continue even after removal of the rejected graft's endothelium. Especially for the one patient regarding whom authors1 of the under discussion article wrote "had multiple previous graft failure, requiring placement of an investigational ciclosporine implant to prevent further rejection." Should we do EK or PK in PK rejection cases? Perhaps a longer follow up will answer this question. References: 1. Nottage JM, Nirankari VS. Endothelial keratoplasty without Descemet's stripping in eyes with previous penetrating corneal transplants. Br J Ophthalmol. 2012 Jan;96(1):24-7 2. Chen ES, Terry MA, Shamie N, Hoar KL, Phillips PM, Friend DJ. Endothelial keratoplasty: vision, endothelial survival, and complications in a comparative case series of fellows vs attending surgeons. Am J Ophthalmol. 2009 Jul;148(1):26-31.e2. Epub 2009 Apr 17. 3. Straiko MD, Terry MA, Shamie N. Descemet stripping automated endothelial keratoplasty under failed penetrating keratoplasty: a surgical strategy to minimize complications. Am J Ophthalmol. 2011 Feb;151(2):233- 7.e2. Epub 2010 Dec 3. 4. Li JY, Terry MA, Goshe J, Shamie N, Davis-Boozer D. Graft rejection after descemet's stripping automated endothelial keratoplasty graft survival and endothelial cell loss. Ophthalmology. 2012 Jan;119(1):90-4. Epub 2011 Nov 23.

Conflict of Interest:

None declared