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Rotterdam, Netherlands

Bruinsma M.,Netherlands Institute for Innovative Ocular Surgery | Lie J.T.,Amnitrans EyeBank Rotterdam | Groeneveld-Van Beek E.A.,Amnitrans EyeBank Rotterdam | Liarakos V.S.,Netherlands Institute for Innovative Ocular Surgery | And 2 more authors.

PURPOSE: To study the validity of endothelial polymegethism, pleomorphism, and "poor swelling" as tissue discard parameters in the immediate postmortem evaluation of human donor corneal endothelium. METHODS: We retrospectively evaluated the quality of the endothelium at first and second evaluations for all processed corneas exhibiting moderate polymegethism, pleomorphism, or "poor swelling" in our eye bank over a 5-year period. RESULTS: Out of 2008 eyes qualifying for our study, 422 corneas (21%) showed polymegethism, pleomorphism, or poor swelling at the first tissue evaluation immediately after excision of the corneoscleral button. In 363 (86%) of these corneas, a normal endothelial mosaic was observed at the second tissue evaluation after 7 to 21 days of organ culture, whereas only 59 (14%) still showed persistent polymegethism, pleomorphism, or "poor swelling" at that time point. CONCLUSIONS: A recovery of normal endothelial cell mosaic and "normal swelling" at the second evaluation suggests that cellular contour parameters do not relate to tissue viability, but rather to a cellular stress reaction. If so, the validity of endothelial cellular contour morphology as an early parameter in assessing the suitability of a donor cornea for transplantation may be reconsidered. Copyright © 2012 by Lippincott Williams & Wilkins. Source

Lie J.T.,Amnitrans EyeBank Rotterdam | Monnereau C.,Netherlands Institute for Innovative Ocular Surgery | Groeneveld-van Beek E.A.,Amnitrans EyeBank Rotterdam | van der Wees J.,Amnitrans EyeBank Rotterdam | And 5 more authors.
Cell and Tissue Banking

Anterior donor grafts (including scleral rim, without Descemet membrane) increase in thickness and become hazy upon storage in organ culture (OC) medium. Transfer of these grafts to standard dehydration media just before transplantation does not reduce their thickness to normal. Therefore, we assessed the efficacy of different media enriched with polyethylene glycol (PEG) as dehydrating agents for organ-cultured anterior donor grafts. Grafts were harvested and stored in the commercial OC medium ‘Max’ (without dextran) for 1 week, and subsequently dehydrated in the standard commercial dehydration medium ‘Jet’ (with dextran) supplemented with 4–20 % PEG3350, or ‘Max’ supplemented with 20 % PEG6000 and PEG20.000, or 5–20 % PEG35.000. Central corneal thickness (CCT), as assessed by anterior segment-optical coherence tomography, and transparency were evaluated before, and at 1, 4 and 7 days of dehydration. Transfer of grafts after 1 week of OC (average 1,200 µm) to ‘Jet’ supplemented with PEG3350 revealed a concentration-dependent effect of dehydration; CCT was restored to normal (500–600 µm) when 10 % PEG3350 was added. However, transparency was only temporarily restored; after 1 day, the grafts turned hazy. In contrast, grafts transferred to ‘Max’ supplemented with 20 % PEG35.000 were transparent throughout the evaluation period, but were dehydrated to beyond normal levels (average 300 µm). ‘Max’ supplemented with 5 % PEG35.000 dehydrated grafts to normal values and restored transparency throughout. Thus, dehydration of anterior donor grafts prior to surgery in dextran-free OC medium supplemented with 5 % PEG35.000 reduces graft thickness to normal and may facilitate anterior keratoplasty procedures. © 2014, Springer Science+Business Media Dordrecht. Source

Groeneveld-Van Beek E.A.,Amnitrans EyeBank Rotterdam | Lie J.T.,Amnitrans EyeBank Rotterdam | Van Der Wees J.,Amnitrans EyeBank Rotterdam | Bruinsma M.,Amnitrans EyeBank Rotterdam | And 3 more authors.
Acta Ophthalmologica

Purpose: To describe a standardized 'no-touch' harvesting technique of anterior and Descemet membrane (DM) grafts for use in deep anterior lamellar keratoplasty (DALK) and Descemet membrane endothelial keratoplasty (DMEK), which provides undamaged anterior and posterior corneal grafts. Methods: A retrospective evaluation was performed of our standard method for harvesting DM grafts and DALK grafts (Technique I; n = 31) versus a newly designed 'no-touch' technique (Technique II; n = 31), in which a peripheral ring of trabecular meshwork tissue is left in-situ, and the DM graft is trephined on an underlying soft contact lens. Endothelial cell density (ECD) before and immediately after DM stripping was used as the main outcome parameter. Results: Endothelial cell density did not differ within Techniques I and II (before versus after DM stripping) (p = 0.75 and p = 0.54, respectively) or among Techniques I and II (p = 0.61). With the latter technique, anterior corneal grafts and posterior DM grafts could be harvested with negligible damage to the endothelial cell layer or the posterior stromal bed. All 93 grafts (62 DM grafts) were eligible for transplantation, and six months post-operatively all transplants used were functional. Conclusion: The new technique offers the following advantages: (i) production of 'undamaged' grafts for DALK and DMEK, (ii) better controlled tissue handling of the thin DM graft during DM stripping and (iii) an increase in availability of corneal grafts obtained from the same donor tissue pool. © 2012 Acta Ophthalmologica Scandinavica Foundation. Source

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