Assessment of Eye Bank–Prepared Posterior Lamellar Corneal Tissue for Endothelial Keratoplasty (original) (raw)
Eye-bank preparation of endothelial tissue
Current Opinion in Ophthalmology, 2014
Purpose of review-Eyebank preparation of endothelial tissue for keratoplasty continues to evolve. While eye bank personnel have become comfortable and competent at Descemet Stripping Automated Endothelial Keratoplasty (DSAEK) tissue preparation and tissue transport, optimization of preparation methods continues. Surgeons and eye bank personnel should be up to date on the research in the field. As surgeons transition to Descemet Membrane Endothelial Keratoplasty (DMEK), eye banks have risen to the challenge of preparing tissue. Eye banks are refining their DMEK preparation and transport techniques Recent findings-This article covers refinements to DSAEK tissue preparation, innovations to prepare DMEK tissue, and nuances to improve donor cornea tissue quality. Summary-As eye bank supplied corneal tissue is the main source of tissue for many corneal surgeons, it is critical to stay informed about tissue handling and preparation. Ultimately the surgeon is responsible for the transplantation, so involvement of clinicians in eye banking practices and advocacy for pursuing meaningful research in this area will benefit clinical patient outcomes.
Corneal Donor Tissue Preparation for Descemet's Membrane Endothelial Keratoplasty
Journal of Visualized Experiments, 2014
Over the past ten years, corneal transplantation surgical techniques have undergone revolutionary changes 1,2 . Since its inception, traditional full thickness corneal transplantation has been the treatment to restore sight in those limited by corneal disease. Some disadvantages to this approach include a high degree of post-operative astigmatism, lack of predictable refractive outcome, and disturbance to the ocular surface. The development of Descemet's stripping endothelial keratoplasty (DSEK), transplanting only the posterior corneal stroma, Descemet's membrane, and endothelium, has dramatically changed treatment of corneal endothelial disease. DSEK is performed through a smaller incision; this technique avoids 'open sky' surgery with its risk of hemorrhage or expulsion, decreases the incidence of postoperative wound dehiscence, reduces unpredictable refractive outcomes, and may decrease the rate of transplant rejection 3-6
Descemet Membrane Endothelial Keratoplasty (DMEK) selectively replaces the damaged posterior part of the cornea. However, the DMEK technique relies on a manually-performed dissection that is timeconsuming, requires training and presents a potential risk of endothelial graft damages leading to surgery postponement when performed by surgeons in the operative room. To validate precut corneal tissue preparation for DMEK provided by a cornea bank in order to supply a quality and security precut endothelial tissue. The protocol was a technology transfer from the Netherlands Institute for Innovative Ocular Surgery (NIIOS) to Lyon Cornea Bank, after formation in NIIOS to the DMEK ''no touch'' dissection technique. The technique has been validated in selected conditions (materials, microscope) and after a learning curve, cornea bank technicians prepared endothelial tissue for DMEK. Endothelial cells densities (ECD) were evaluated before and after preparation, after storage and transport to the surgery room. Microbiological and histological controls have been done. Twenty corneas were manually dissected; 18 without tears. Nineteen endothelial grafts formed a double roll. The ECD loss after cutting was 3.3 % (n = 19). After transportation 7 days later, we found an ECD loss of 25 % (n = 12). Three days after cutting and transportation, we found 2.1 % of ECD loss (n = 7). Histology found an endothelial cells monolayer lying on Descemet membrane. The mean thickness was 12 ± 2.2 lm (n = 4). No microbial contamination was found (n = 19). Endothelial roll stability has been validated at 3 days in our cornea bank. Cornea bank technicians trained can deliver to surgeons an ECD controlled, safety and ready to use endothelial tissue, for DMEK by ''no touch'' technique, allowing time saving, quality and security for surgeons.
Donor Tissue Culture Conditions and Outcome after Descemet Membrane Endothelial Keratoplasty
American Journal of Ophthalmology, 2011
PURPOSE: To investigate the effect of culture conditions of donor tissue on functional outcome after Descemet membrane endothelial keratoplasty. • DESIGN: Retrospective, single-center, consecutive case series. • METHODS: Descemet membrane endothelial keratoplasty was performed routinely in 82 eyes of 82 consecutive patients using corneal donor tissue prestored in either short-term culture (Optisol-GS; Bausch & Lomb) at 4 C (group A; n ؍ 37) or organ culture (Dulbecco Modified Eagle Medium [Biochrom]; CorneaMax Medium [Eurobio]) at 34 C (group B; n ؍ 45) in a randomized fashion. Main outcome measures included the number of air injections necessary for graft attachment as well as best-corrected visual acuity (in logarithm of the minimal angle of resolution [logMAR] units), central corneal thickness, and endothelial cell density at 1, 3, and 6 months after surgery. • RESULTS: Best-corrected visual acuity increased from 0.69 ؎ 0.53 logMAR and 0.67 ؎ 0.31 logMAR before surgery to 0.33 ؎ 0.21 logMAR and 0.28 ؎ 0.18 logMAR after 1 month (P < .05), to 0.24 ؎ 0.16 logMAR and 0.18 ؎ 0.16 logMAR after 3 months (P < .05), and to 0.18 ؎ 0.12 logMAR and 0.15 ؎ 0.10 logMAR after 6 months (n.s.) in groups A and B, respectively. Endothelial cell density decreased from 2647 ؎ 236 cells/mm 2 and 2515 ؎ 249 cells/mm 2 before surgery to 1499 ؎ 277 cells/mm 2 and 1526 ؎ 205 cells/mm 2 after 1 month (P < .05), to 1441 ؎ 213 cells/mm 2 and 1443 ؎ 316 cells/mm 2 after 3 months (n.s.), and to 1587 ؎ 366 cells/mm 2 and 1457 ؎ 285 cells/mm 2 after 6 months (n.s.) in groups A and B, respectively. Central corneal thickness declined from 664 ؎ 89 and 662 ؎ 107 m before surgery to 529 ؎ 92 m and 517 ؎ 62 m after 1 month (P < .05), to 511 ؎ 46 m and 510 ؎ 46 m after 3 months (P < .05), and to 529 ؎ 68 m and 507 ؎ 50 m after 6 months (n.s.) in groups A and B, respectively. Bestcorrected visual acuity, endothelial cell density, and central corneal thickness values showed no significant differences between both groups at any time point after surgery. However, a significantly higher total number of air injections was necessary in group A (n ؍ 34) compared with group B (n ؍ 26) to obtain graft attachment (P < .05). • CONCLUSIONS: These findings suggest that donor tissue culture conditions have no significant effect on functional outcome, but may influence graft adhesion and rebubbling rate after Descemet membrane endothelial keratoplasty surgery. (Am J Ophthalmol 2011;151:1007-1018.
Cornea, 2018
To describe the technique, advantages, and early complication rates of using Descemet membrane endothelial keratoplasty (DMEK) donor tissue that is prestained and preloaded into an injector at the eye bank and delivered in a storage medium to the surgeon for transplantation 1 to 2 days later. A total of 111 eyes with endothelial failure underwent DMEK using donors that were prestripped, prestained, S-stamped, and preloaded into a Straiko modified Jones tube and delivered in an Optisol-filled viewing chamber 1 to 2 days later. Scroll tightness, time to unscroll and center the tissue, postoperative rebubble rate, and graft failure rate were recorded. Endothelial cell density was measured at 3 and 6 months. All tissues remained well stained with easy visualization at the time of surgery (n = 111). The mean scroll tightness was 2.2 (range: 1-4). The mean time to center and unscroll the tissue was 3.5 minutes (range: 0.5-11.25 min). There was no primary graft failure. There were 16 cases...
Cornea, 2017
To share the experience and provide a standardized protocol for Descemet membrane endothelial keratoplasty (DMEK) graft preparation. A retrospective study based on 527 prestripped DMEK tissues that were prepared between 2014 and 2017. The experience of using different instruments and techniques has been described, and a standardized technique for preparing DMEK grafts has been identified. The tissues in general were prepared by superficially tapping the endothelial side with a Moria trephine (9.5 mm diameter). The plane of cleavage was identified using a cleavage hook, and the DMEK graft was deadhered from the trephined site throughout the circumference for ease of excising the graft. The DMEK graft was peeled using either one or multiple quadrant methods depending on the challenges faced during excision. The graft was finally marked with the letter "F" to identify the orientation during surgery. Data on endothelial cell loss (ECL) and challenging cases were observed, moni...