Donor Descemet Membrane Research Articles

Comparison of Descemet-On Versus Descemet-Off Deep Anterior Lamellar Keratoplasty

To determine the effect of retained donor Descemet membrane (DMs) on visual outcomes, contrast sensitivity (CS), higher-order aberrations (HOAs), and central graft thickness after deep anterior lamellar keratoplasty (DALK) using the big-bubble technique. In this retrospective comparative study, keratoconic eyes undergoing a DALK using the big-bubble technique were enrolled. A bared DM was achieved in all cases. A donor cornea without (group 1; 48 eyes) or with (group 2; 22 eyes) DM was sutured to the recipient bed. The 2 groups were compared in terms of best spectacle-corrected visual acuity, keratometric astigmatism, refractive error, CS, HOAs, and central graft thickness at least 3 months after complete suture removal. Additionally, the rate of postoperative pseudoanterior chamber formation was compared between the study groups. The mean follow-up duration was 23.2 ± 6.9 months in group 1 and 26.5 ± 6.5 months in group 2 (P = 0.61). The postoperative best spectacle-corrected visual acuity was 0.18 ± 0.08 logMAR and 0.24 ± 0.30 logMAR, respectively (P = 0.36). The 2 groups had comparable postoperative keratometric astigmatism, spherical equivalent refraction, and HOAs. In terms of CS, however, group 1 demonstrated better results at a low spatial frequency. The mean postoperative central graft thickness was greater in group 2 (589.8 ± 34.5 μm) than in group 1 (523.6 ± 63.0 μm; P < 0.001). A pseudoanterior chamber developed in 3 eyes of group 1 and in 2 eyes of group 2 (P = 0.23). All cases were successfully managed by giving an intracameral air injection. DALK performed using the big-bubble technique for keratoconus may give better results in terms of CS if a donor cornea without DM is transplanted.

Use of Accidentally Torn Descemet Membrane to Successfully Complete Descemet Membrane Endothelial Keratoplasty

To describe the use of an accidentally torn Descemet membrane (DM) to successfully complete Descemet membrane endothelial keratoplasty (DMEK) surgery. Retrospective, observational case series of 3 eyes of 3 patients undergoing DMEK with a DM accidentally torn into 2 pieces during graft preparation. The mean outcome measures included best-corrected visual acuity, endothelial cell density, and central corneal thickness, before and at 1, 3, and 6 months after the DMEK surgery was performed. During graft preparation, immediately before transplantation, a large tear within the 8.0-mm marking line of the DM occurred, resulting in a DM torn into 2 pieces. In all the eyes, both pieces were successfully implanted into the anterior chamber, unfolded and attached to the posterior corneal stroma, one after the other. Six months after the surgery was performed, the best-corrected visual acuity ranged between 20/30 and 20/25. Endothelial cell loss was about 30% (range 28%-32%) 6 months after the surgery. Pachymetry findings showed normal corneal thickness 6 months after the surgery. All corneas remained clear without any signs of graft failure within 6 months of follow-up. DMEK surgery can be successfully completed despite the accidental tearing of donor DMs during the preparation of DMEK grafts by the sequential implantation of both DM pieces.

What does the future hold for the treatment of Fuchs endothelial dystrophy; will ‘keratoplasty’ still be a valid procedure?

Fuchs endothelial corneal dystrophy (FECD) is a well recognized corneal disorder characterized by the presence of collagenous warts extending from Descemet membrane (guttae) and endothelial cellular dysfunction due to cell loss and/or degeneration. Because of the characteristic abnormal cell morphology as seen with specular microscopy as well as the limited regenerative capacity in vivo, the endothelial cells were considered to be 'dystrophic'. Hence, FECD is commonly managed by replacement of the endothelium with donor tissue by means of a penetrating or endothelial keratoplasty. The latter procedure has now been refined to the isolated transplantation of a donor Descemet membrane and its endothelium, referred to as Descemet membrane endothelial keratoplasty (DMEK). Unexpectedly, clinical observation made after DMEK seemed to challenge the current concept of the state of the endothelium in FECD; we actually observed an important role for the 'dystrophic' host endothelium in re-endothelialization of the denuded DM, and subsequent corneal clearance. In addition, recent studies regarding the pathophysiology of FECD made us realize that the endothelial cells are not 'dystrophic' per se, but in the course of time may have acquired a dysfunction instead. This paper describes the rationale behind this new concept and based on this, discusses the possibilities for future, less invasive treatment modalities for FECD.

Novel Maneuver Facilitating Descemet Membrane Unfolding in the Anterior Chamber

To describe a new technique for unfolding of the Descemet membrane (DM) during Descemet membrane endothelial keratoplasty. DM and endothelium were stripped from donor corneas submerged in corneal storage solution. Donor DM diameters were 8.5 mm. The central 8 mm of DM was stripped from the recipient cornea. After staining with trypan blue to improve visualization, donor DM was inserted through a 2.75-mm incision. Unfolding was achieved with simultaneous digital pressure in the equatorial region and tapping of the corneal surface. This technique was performed in Descemet membrane endothelial keratoplasty patients with Fuchs endothelial dystrophy (n = 6) and bullous keratopathy (n = 4). In all cases, a fast attachment of the DM was achieved. The recurling was successfully hindered because of the simultaneous equatorial pressurization and induced fluid currents inside the anterior chamber by appropriate corneal tapping. In all cases, a rapid corneal clearance was achieved with significantly increased visual acuity (logarithm of the minimal angle of resolution visual acuity preoperative = 0.90, logarithm of the minimal angle of resolution visual acuity final assessment = 0.19, P < 0.001; follow-up 14 ± 5 weeks). Simultaneous digital pressure with corneal tapping is a helpful maneuver to unfold the DM inside the anterior chamber. This technique may reduce the need for unnecessary instrumental and noninstrumental manipulation of the graft.

Visual acuity and endothelial cell density following Descemet membrane endothelial keratoplasty (DMEK)

PurposeTo assess the clinical outcomes of DMEK in the first series of 120 eyes operated for the treatment of Fuchs endothelial dystrophy in terms of visual acuity and endothelial cell density. MethodsThe first 120 consecutive eyes that underwent DMEK (i.e. transplantation of an isolated donor Descemet membrane with its endothelium) were evaluated. In all eyes, the best corrected visual acuity (BCVA) before and at 1, 3 and 6 months after surgery, as well as the endothelial cell density (ECD) before and at 6 months were measured. ResultsIn eyes with a functional DMEK graft and good visual potential (n=96), the BCVA was ≥20/40 (≥0.5) in 77% after 1 month, 92% after 3 months, and 95% after six months; ≥20/25 (≥0.8) in 50%, 63%, and 73% of the cases, and ≥20/20 (≥1.0) in 23%, 34%, and 45% of the cases at 1, 3, and 6 months, respectively. In this group, ECD averaged 2610 (±185)cells/mm2 before, and 1770 (±520)cells/mm2 at six months after surgery (n=96). In 15 eyes, a secondary Descemet stripping endothelial keratoplasty (DSEK) was performed. In this group, 91% of patients reached a BCVA of ≥20/40 (≥0.5) and only one patient achieved a BCVA of 0.8 at 6 months after surgery (n=11). Furthermore, ECD averaged 2580 (±185)cells/mm2 before and 1310 (±740)cells/mm2 at six months (n=13). ConclusionDMEK provides a fast and high visual rehabilitation. Endothelial cell density loss may be similar to earlier types of endothelial keratoplasty.

Agudeza visual y densidad de células endoteliales tras queratoplastia endotelial de membrana de Descemet (DMEK)

Purpose To assess the clinical outcomes of DMEK in the first series of 120 eyes operated for the treatment of Fuchs endothelial dystrophy in terms of visual acuity and endothelial cell density. Methods The first 120 consecutive eyes that underwent DMEK (i.e. transplantation of an isolated donor Descemet membrane with its endothelium) were evaluated. In all eyes, the best corrected visual acuity (BCVA) before and at 1, 3 and 6 months after surgery, as well as the endothelial cell density (ECD) before and at 6 months were measured. Results In eyes with a functional DMEK graft and good visual potential (n = 96), the BCVA was ≥ 20/40 (≥ 0.5) in 77% after 1 month, 92% after 3 months, and 95% after six months; ≥ 20/25 (≥ 0.8) in 50%, 63%, and 73% of the cases, and ≥ 20/20 (≥ 1.0) in 23%, 34%, and 45% of the cases at 1, 3, and 6 months respectively. In this group, ECD averaged 2610 (±185) cells/mm 2 before, and 1770 (±520) cells/mm 2 at six months after surgery (n = 96). In 15 eyes, a secondary Descemet stripping endothelial keratoplasty (DSEK) was performed. In this group, 91% of patients reached a BCVA of ≥ 20/40 (≥ 0.5) and only one patient achieved a BCVA of 0.8 at 6 months after surgery (n = 11). Furthermore, ECD averaged 2580 (±185) cells/mm 2 before and 1310 (±740) cells/mm 2 at six months (n = 13). Conclusion DMEK provides a fast and high visual rehabilitation. Endothelial cell density loss may be similar to earlier types of endothelial keratoplasty.

Secondary “Thin-DSEK” After Long-term Graft Failure in DLEK: A Double Transplanted Cornea

To describe a case of secondary "thin Descemet stripping endothelial keratoplasty" ("Thin-DSEK"), for borderline decompensation 6 years after an initial deep lamellar endothelial keratoplasty (DLEK). In a 31-year-old man, who initially underwent a DLEK for bullous keratopathy in the presence of a phakic intraocular lens, a secondary Thin-DSEK was performed, while leaving the entire DLEK graft (including the donor Descemet membrane and the endothelium) in situ. After the initial DLEK, the best-corrected visual acuity (BCVA) improved from 20/200 (0.1) to 20/25 (0.8). Six years later, the transplanted cornea showed intermittent decompensation with a decrease in BCVA again to 20/200 (0.1). After the secondary Thin-DSEK, the BCVA improved again to 20/25 (0.8) at 1 month postoperatively and remained stable thereafter. Our case may show that a secondary DSEK may be a simple and effective treatment to manage secondary graft failure after DLEK. Despite the presence of a "double" stromal interface in the visual axis, secondary Thin-DSEK may provide visual rehabilitation similar to that after primary Thin-DSEK.

A Surgical Technique for Donor Tissue Harvesting for Descemet Membrane Endothelial Keratoplasty

To create a reproducible and effective technique in donor tissue harvesting for Descemet membrane (DM) endothelial keratoplasty. A new method has been developed for the harvest of donor DM and endothelium. This method involves placement of a human corneoscleral rim in an artificial anterior chamber with removal of the anterior stroma with a Moria One microkeratome (Moria USA, Doylestown, PA). The residual stromal bed over the central cornea is removed by blunt dissection using a Barraquer sweep. A thin rim of posterior residual stroma permits easy donor button trephination and tissue manipulation. The risk of tearing through DM is minimal and may not preclude use in transplantation. This method allows relatively easy assessment of endothelial integrity before trephination. Optical coherence tomography evaluation revealed minimal stroma overlying DM and endothelium. Endothelial cell integrity of the harvested DM by this new harvest method was assessed using specular microscopy and demonstrated minimal loss after DM harvest. We presented a manual tissue harvest method for DM endothelial keratoplasty.

Automated Donor Tissue Preparation for Descemet Membrane Automated Endothelial Keratoplasty (DMAEK): An Experimental Study

Graft harvesting for Descemet membrane endothelial keratoplasty (DMEK) occurs manually and demonstrates surgical difficulties. In the current study, a mechanical automated technique for preparing a donor Descemet membrane (DM) carrying autologous endothelium for DMEK was evaluated. Ten rabbit corneas were placed on an artificial anterior chamber and mechanical separation of the DM was conducted using an Epi-keratome (Senturium; Norwood Abbey EyeCare, Victoria, Australia). All DM specimens were properly fixated and optical microscopy was performed. DM separation was achieved in a controlled fashion in 7 of 10 eyes. As demonstrated by optical microscopy of the specimens, no corneal stroma was attached on the DM, whereas the endothelial layer was preserved in several areas. Automated separation of the DM can be achieved using an Epi-keratome. Additional studies and improvements of the current technique are needed to draw final conclusions.

Visus nach Descemet-Membran Endothelkeratoplastik (DMEK): Ergebnisse der ersten 100 Eingriffe bei Fuchs’scher Endotheldystrophie

The aim of this study was to evaluate the visual outcome and endothelial cell density in the first series of 100 eyes after Descemet membrane endothelial keratoplasty (DMEK) for the treatment of Fuchs endothelial dystrophy. This was a non-randomised prospective clinical trial. The first 100 consecutive eyes (87 patients) that underwent DMEK (i. e., transplantation of an isolated donor Descemet membrane carrying its endothelium) for Fuchs endothelial dystrophy were evaluated. In all eyes, the best corrected visual acuity (BCVA) as well as the endothelial cell density (ECD) were measured before and at one, three and six months after surgery. In eyes with a functional DMEK graft and good visual potential (n = 78), the BCVA was > or = 20 / 40 (> or = 0.5) in 79 % after 1 month, 94 % after 3 months, and 96 % after six months; > or = 20 / 25 (> or = 0.8) in respectively 54 %, 64 %, and 74 %, and > or = 20 / 20 (> or = 1.0) in respectively 26 %, 36 %, and 45 %. In this group, ECD averaged 2630 (+/- 190) cells/mm (2) before, and 1800 (+/- 540) cells/mm (2) at six months after surgery (n = 76). In 15 eyes, a secondary "Descemet stripping endothelial keratoplasty" (DSEK) was performed. When the outcomes of DMEK and secondary DSEK procedures were combined, 91 % reached a BCVA of > or = 20 / 40 (> or = 0.5), 65 % > or = 20 / 25 (> or = 0.8) and 38 % > or = 20 / 25 (> or = 1.0) at six months after surgery (n = 93). For the whole group, ECD averaged 2620 (+/- 190) cells/mm (2) before, and 1730 (+/- 590) cells/mm (2) at six months after surgery (n = 89). DMEK may provide relatively quick and nearly complete visual rehabilitation in a majority of patients operated on for Fuchs endothelial dystrophy. Endothelial cell survival may be similar to earlier types of endothelial keratoplasty. Early graft detachment (19 cases) was the main complication in this first series of DMEK surgeries.

Descemet's Membrane Endothelial Keratoplasty: Prospective Multicenter Study of Visual and Refractive Outcomes and Endothelial Survival

To describe Descemet's membrane endothelial keratoplasty (DMEK) techniques, perioperative challenges, management, and visual and refractive outcomes. Prospective, multicenter, consecutive case series. Sixty eyes of 56 patients with Fuchs' endothelial dystrophy, pseudophakic bullous keratopathy, or failed previous graft. Descemet's membrane (DM) and endothelium were stripped from donor corneas submerged in corneal storage solution in a corneal viewing chamber. Donor DM diameters were 8.5 or 9.0 mm. The central 7 mm of DM was stripped from the recipient cornea. After staining with trypan blue to improve visualization, donor DM was inserted through a 2.8-mm incision. Descemet's membrane endothelial keratoplasty was performed alone (n = 48) or was combined with phacoemulsification and lens implantation (n = 11), pars plana vitrectomy (n = 2), or both. Best spectacle-corrected visual acuity (BSCVA), manifest refraction, and endothelial cell density. Median BSCVA was 20/30 at 1 month (range, 20/20-20/60), improving from 20/50 (range, 20/25-hand movements) before DMEK, excluding 4 eyes (7%) with preexisting ocular pathologic features that limited visual potential. At 3 months, 26% had 20/20 vision, 63% saw 20/25 or better, and 94% saw 20/40 or better. Refractive cylinder remained unchanged at 0.9 diopters (D; P = 0.93), and a hyperopic shift of 0.49+/-0.63 D (P = 0.0091) was noted in DMEK single procedures. Endothelial cell loss was 30%+/-20% at 3 months and 32%+/-20% in 38 eyes that reached the 6-month examination. Median pachymetry decreased from 660 mum before surgery to 530 mum. Descemet's membrane stripped successfully from 60 of 72 donor corneas; 6 were converted successfully to Descemet's stripping automated endothelial keratoplasty (DSAEK) and 6 (8%) were discarded. Only 1 graft detached completely, but air was reinjected in 38 eyes (63%), mainly for partial detachments. Five DMEK corneas (8%) failed to clear and were replaced successfully with DMEK or DSAEK. All remained clear at last follow-up. Compared with DSAEK, DMEK provided a significantly higher rate of 20/20 and 20/25 vision, with comparable endothelial cell loss. Descemet's membrane endothelial keratoplasty restored physiologic pachymetry, but donor preparation and attachment currently are more challenging than with DSAEK.

Descemet membrane endothelial keratoplasty (DMEK) for Fuchs endothelial dystrophy: review of the first 50 consecutive cases

To evaluate the clinical outcome and complications of Descemet membrane endothelial keratoplasty (DMEK), using Descemet-stripping endothelial keratoplasty (DSEK) as a back-up procedure, in the management of Fuchs endothelial dystrophy. Non-randomised prospective clinical study. The first fifty consecutive eyes that underwent DMEK, that is, transplantation of an isolated donor Descemet membrane carrying its endothelium, for Fuchs endothelial dystrophy were evaluated. In all eyes, the best-corrected visual acuity (BCVA) as well as the endothelial cell density (ECD) was measured before and at 6 months after surgery, as clinical outcome parameters. Ten patients required a secondary DSEK for failed DMEK. In the remaining 40 DMEK eyes, 95% had a BCVA of > or = 20/40 (> or = 0.5) and 75% > or = 20/25 (> or = 0.8) at 6 months after surgery. ECD averaged 2618 (+ or - 201) cells/mm(2) before, and 1876 (+ or - 522) cells/mm(2) at 6 months after surgery (n = 35). When the outcomes of DMEK and secondary DSEK procedures were combined, 94% reached a BCVA of > or = 20/40 (> or = 0.5) and 66% > or = 20/25 (> or = 0.8) (n = 47), and ECD averaged 2623 (+ or - 193) cells/mm(2) before, and 1815 (+ or - 578) cells/mm(2) at 6 months after surgery (n = 43). With DSEK as a back-up procedure, DMEK may provide relatively quick and complete visual rehabilitation in a majority of patients operated on for Fuchs endothelial dystrophy. Endothelial cell survival may be similar to earlier types of (lamellar) keratoplasty. Early graft detachment was the main complication in this first series of DMEK surgeries for Fuchs endothelial dystrophy.

Donor tissue preparation for Descemet membrane endothelial keratoplasty

To evaluate a technique for preparing a donor Descemet membrane carrying autologous endothelium for transplantation in Descemet membrane endothelial keratoplasty (DMEK). Netherlands Institute for Innovative Ocular Surgery, Rotterdam, The Netherlands. A 9.5 mm diameter DM carrying autologous endothelium was stripped from 10 corneoscleral rims that had been organ cultured for 1 week. The endothelial cell density (ECD) was evaluated with light microscopy before and immediately after DM was stripped and during 4 additional weeks of organ culture. The mean ECD was 2701 cells/mm(2) +/- 302 (SD) before and 2719 +/- 322 cells/mm(2) immediately after DM was stripped and declined from 2604 +/- 352 cells/mm(2) after 1 week to 2190 +/- 768 cells/mm(2) after an additional 4 weeks of organ culture (n = 10). Typical "endothelial streaks," ie, linear cellular disruptions observed immediately after DM was stripped, showed complete regeneration after the second culture period. Descemet grafts for transplantation in DMEK procedures can be surgically prepared from organ-cultured corneal rims and stored for an additional 3 weeks with acceptable endothelial cell loss. Because the donor tissue can be dissected directly from organ-cultured corneoscleral rims, donor preparation for DMEK can be readily accessible to most corneal surgeons.

Causes of Primary Donor Failure in Descemet Membrane Endothelial Keratoplasty

To determine the causes of primary failure of donor Descemet membrane transplants in Descemet membrane endothelial keratoplasty (DMEK). Laboratory and clinical study. From a larger series of eyes that underwent DMEK for Fuchs endothelial dystrophy or bullous keratopathy, 11 transplanted corneas did not clear within the first week after surgery. During a secondary 'Descemet stripping endothelial keratoplasty' procedure, the first graft was carefully removed and analyzed with light microscopy. For each patient, the surgical video of the initial DMEK procedure was analyzed to determine the cause of transplant failure. With light microscopy, all but two explanted transplants had a endothelial cell density of 1700 cells/mm2 or higher. Three Descemet grafts may have been positioned upside down and three may have failed due to manipulation. One transplant could not be properly attached onto the recipient posterior stroma because of insufficient air-support in a post-vitrectomy eye. For four eyes, no obvious cause of failure could be determined. Unexpectedly, graft failure after DMEK may not primarily result from tissue damage during implantation and associated endothelial cell loss. Detached grafts may therefore be managed by early reposition. When the graft is attached after surgery but fails to clear, secondary surgical intervention may be postponed, because these corneas may clear spontaneously after several weeks.

Preliminary Clinical Results of Descemet Membrane Endothelial Keratoplasty

To describe the preliminary clinical results of selective transplantation of organ cultured, donor Descemet membrane (DM) carrying autologous corneal endothelium through a 3.5-mm incision, tentatively named Descemet membrane endothelial keratoplasty (DMEK), for the management of corneal endothelial disorders. Nonrandomized clinical study. In 10 patients with Fuchs endothelial dystrophy or pseudophakic bullous keratopathy, DMEK was performed. A 3.5-mm clear corneal tunnel incision was made, the anterior chamber was filled with air, and DM was stripped off from the posterior stroma. A 9.0-mm diameter DM roll was harvested from an organ cultured donor corneo-scleral rim, and inserted into a recipient anterior chamber. The donor tissue was gently unfolded, positioned onto the posterior stroma, and secured by completely filling the anterior chamber with air for 30 minutes. At one month, six eyes had a best-corrected visual acuity of 0.5 (20/40) or better, and three eyes reached 1.0 (20/20). At six months, the endothelial cell density averaged 2030 (+/-373) cells/mm(2) (n = 7). Three eyes showed a complete detachment of the donor tissue in the early postoperative course that was managed by removal of the transplant and a secondary Descemet stripping endothelial keratoplasty procedure. DMEK may have potential to become the most preferable technique to manage corneal endothelial disorders, because it provides quick and nearly complete visual rehabilitation. Because the donor tissue required can be prepared from organ cultured corneo-scleral rims, the procedure may be readily accessible to most corneal surgeons.

DLEK to DSEK to DMEK

Abstract Purpose: To describe the preliminary clinical results of selective transplantation of organ cultured donor Descemet membrane (DM) carrying autologous corneal endothelium through a 3.5 mm incision, tentatively named Descemet membrane endothelial keratoplasty (DMEK), for the management of corneal endothelial disorders.Design: Non‐randomized clinical trial. Methods: In ten patients with Fuchs’ endothelial dystrophy or pseudophakic bullous keratopathy, DMEK was performed. A 3.5 mm clear corneal tunnel incision was made, the anterior chamber was filled with air, and DM was stripped off from the posterior stroma. A 9.0 mm diameter DM roll was harvested from an organ cultured donor corneo‐scleral rim, and inserted into a recipient anterior chamber. The donor tissue was gently unfolded, positioned onto the posterior stroma, and secured by completely filling the anterior chamber with air for 30 minutes. Results: At one month, six eyes had a best corrected visual acuity of 0.5 (20/40) or better, and three eyes reached 1.0 (20/20) or better. At six months, the endothelial cell density averaged 2030 (± 373) cells/mm2 (n=7). Three eyes showed a complete detachment of the donor tissue in the early postoperative course, that was managed by removal of the transplant and a secondary Descemet stripping endothelial keratoplasty procedure. Conclusions: DMEK may have potential to become the most preferable technique to manage corneal endothelial disorders, because it provides quick and nearly complete visual rehabilitation. Since the donor tissue required can be prepared from organ cultured corneo‐scleral rims, the procedure may be readily accessable to most corneal surgeons.

Alkali-Induced Corneal Neovascularization Is Independent of CXCR2-Mediated Neutrophil Infiltration

To study the role of infiltrating neutrophils in the development of experimental corneal neovascularization (CNV). CNV was induced by alkali injury in normal C57BL/6 mice, and the kinetics of neutrophil recruitment to the cornea and the CNV was detected by histologic analysis at multiple time points. Neutrophil recruitment to the corneas was inhibited by injection of anti-mouse granulocyte monoclonal antibodies (Ly-6G) or neutralizing anti-mouse CXCR2 antibodies. CNV was compared between the control and the specific antibody-treated mice 2 weeks after alkali injury, as quantified by CD31 immunostaining. Corneal vascular endothelial growth factor (VEGF) expression after injury was determined by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemical staining. Many myeloperoxidase-positive neutrophils began to infiltrate the corneas 2 days after injury, but infiltration ceased by 14 days after injury. CNV became evident 7 days after injury, reached a maximal level at 14 days, and decreased thereafter. The mRNA expression of CXCR2 and its ligands, macrophage inflammatory protein 2 (CXCL2/MIP-2), and growth-related protein alpha (CXCL1/KC) increased markedly at 2 days after injury. Injection of either anti-mouse granulocyte monoclonal antibodies (Ly-6G) or neutralizing anti-mouse CXCR2 antibodies markedly, and to a similar extent, inhibited neutrophil recruitment to the cornea, indicating that neutrophil infiltration was mediated primarily by CXCR2. In contrast, these treatments failed to attenuate alkali-induced CNV. VEGF mRNA expression was enhanced 2 days after injury, and VEGF proteins were detected mainly in infiltrating mononuclear cells but not in neutrophils. CXCR2-mediated neutrophil infiltration contributes only marginally to the subsequent development of CNV.

Donor Descemet Membrane Detachment After Endothelial Keratoplasty

To describe histopathologic characteristics of an endothelial keratoplasty (EK) that was performed to treat a previously failed penetrating keratoplasty (PK) and in which the cornea failed to clear after partial detachment of Descemet membrane from the EK donor button. The Descemet membrane and endothelium from the PK were intentionally retained during the EK procedure. After EK, the cornea failed to fully clear in 5 months, and a PK was performed. The removed corneal button was grossly described and routinely processed for hematoxylin-eosin (H&E) and periodic acid-Schiff (PAS) staining, with photographs taken of any pertinent findings. Grossly on the endothelial side, there was some adherent iris pigment delineating an off-center fold in the EK Descemet membrane, consistent with intraoperative observation of a fold across the width of the donor button and postoperative slit-lamp images showing partial detachment of Descemet membrane. Microscopic examination revealed a recipient corneal button from a prior PK centrally and EK donor button attached posteriorly. Descemet membrane was not stripped from the prior PK during EK and was intact. No endothelial cells were detected on the PK Descemet membrane. The anterior stromal surface of the EK was well apposed to the prior PK Descemet membrane, with no pseudoanterior chamber or cleft of any type noted between them. The EK Descemet membrane had a central fold, and the endothelium was markedly attenuated. The EK graft was well apposed with apparent good adherence to the recipient's prior failed PK, and early endothelial failure was attributable to partial Descemet membrane detachment.

Transplantation of Descemet's membrane carrying viable endothelium through a small scleral incision.

To design a technique for transplantation of the Descemet's membrane (DM) as a carrier for its endothelium, while maintaining the low-astigmatic recipient anterior corneal curvature. In a human eye bank eye model, recipient eyes (n = 15) had a 5.0-mm scleral tunnel incision made, extending 1.0 mm into the peripheral cornea. A 9.0-mm-diameter Descemeto rhexis was created, i.e., a circular portion of DM was stripped from the posterior stroma. With use of a custom-made inserter, a 9.0-mm-diameter donor DM carrying autologous donor endothelium was brought into the anterior chamber and positioned against the recipient posterior stroma. The procedure was evaluated by keratometry, endothelial vital and supravital staining, and light microscopy. Mean postoperative astigmatism was 1.0 D (+/-0.6 D). Implanted donor DM showed an intact endothelial cell layer, with 3.4% (+/-1.1%) dispersed focal cell death. Microscopy showed normal endothelial cell morphology and complete apposition of the donor DM against the recipient posterior stroma. DM can be transplanted in vitro with acceptable damage to the donor endothelium and with little induced astigmatism.

Retrocorneal Membrane After Penetrating Keratoplasty

Retrocorneal membranes after penetrating keratoplasty (PKP) is a well known complications, resulting from unintentional retention of the host Descemet's membrane (DM), or donor DM detachment. We describe for the first time the formation of a retrocorneal inflammatory membrane that mimics donor DM detachment or retained recipient DM, and discuss the differential diagnosis of a retrocorneal membrane after PKP. Two patients who underwent PKP and subsequently developed a retrocorneal membrane are described. In both patients' eyes a retrocorneal membrane was observed immediately following penetrating keratoplasty. While the first patient's membrane persisted for 33 months in the presence of a clear graft, the second patient's membrane disintegrated and dissolved within two weeks following treatment with topical steroids. The first case describes a patient with retained Descemet's membrane, while in the second case, it turned out that the retrocorneal membrane was actually an inflammatory membrane.