Endothelial keratoplasty is an exciting alternative to full-thickness penetrating keratoplasty for replacing the diseased endothelium, yet 3 of the major complications seen are dislocation of the ...donor tissue, primary graft failure (PGF), and pupillary block from the residual, supportive air bubble. Surgical strategies were developed to reduce the likelihood of occurrence of these complications in our first 200 consecutive Descemet's stripping automated endothelial keratoplasty (DSAEK) cases.
Prospective, noncomparative, interventional case series.
Two hundred eyes of 172 patients with corneal edema.
An institutional review board-approved, prospective protocol of endothelial keratoplasty was initiated. Four different surgeons performed DSAEK for the initial 200 consecutive cases using a technique of peripheral recipient bed scraping for donor edge adherence and leaving a residual supportive air bubble, which was freely mobile, and <or=9 mm in diameter. The incidence of early postoperative complications was then determined.
Postoperative donor graft dislocation, iatrogenic PGF, and pupillary block glaucoma.
There were only 3 dislocations into the anterior chamber in this series of 200 consecutive eyes (1.5% dislocation rate) and all were successfully reattached with a second air bubble. There were no dislocations in the last 115 consecutive cases. There were two cases of donors that were attached but decentered in this series. There were no PGFs. There was not a single case of pupillary block in the entire series.
The surgical technique described in this series, which utilized peripheral recipient bed scraping, has an acceptably low dislocation rate (1.5%) and yielded no cases of iatrogenic PGF. The complication of pupillary block was never seen in this series, likely due to our technique of utilizing a freely mobile, <or=9 mm residual air bubble at the conclusion of surgery.
To determine graft quality and feasibility of Descemet membrane endothelial keratoplasty (DMEK) grafts that are prestripped and preloaded into injectors by eye bank technicians before shipping to ...surgeons.
DMEK grafts (n = 31) were prepared from donor corneas and preloaded into Straiko Modified Jones tubes and set inside viewing chambers filled with 20 mL of Optisol-GS. Preloaded grafts were evaluated using specular microscopy and slit-lamp biomicroscopy. Endothelial cell loss (ECL) was captured by vital dye staining and quantified using FIJI. A subset of preloaded tissues was subjected to a shipping validation and 5-day storage assay. Fourteen additional DMEK grafts (not preloaded) were examined to quantify damage resulting from prestripping alone.
Specular microscopy was able to be performed for all preloaded tissues. Average ECL for preloaded tissues quantified by vital dye staining and FIJI after overnight storage was 16.8% ± 5.9%, and differed from slit-lamp ECL estimation by an average of 5.3% ± 3.6%. The average damage caused by prestripping alone was 9.3% ± 5.9%, and it was significantly less than that of preloaded tissues (P < 0.01). Average ECL for preloaded tissues subjected to round-trip shipping events was 18.5% ± 12.4%, and ECL for tissues stored at 4°C for 5 days after preloading was 13.1% ± 9.5%.
It is possible to prepare, evaluate, and ship DMEK grafts loaded inside a glass carrier and viewing chamber. The ability to evaluate tissues after processing allows for adherence to the Eye Bank Association of America Medical Standards, and for surgeons to receive the most accurate tissue information.
To evaluate the effects of graft rejection episodes after Descemet's stripping automated endothelial keratoplasty surgery (DSAEK) on long-term endothelial cell density (ECD) decline and graft ...survival.
Retrospective, comparative analysis of an interventional case series.
We included 615 eyes of 415 Fuchs' dystrophy patients at a single institution with ≥ 6 months follow-up and without comorbidities known to influence postoperative ECD. All patients were enrolled as part of an ongoing, institutional review board-approved clinical protocol for a long-term, prospective study of endothelial keratoplasty in patients with endothelial dysfunction.
Preoperative specular microscopy of donor corneal tissue was performed. Postoperative specular microscopy measurements were recorded at 6 and 12 months, and yearly thereafter. The percentages of endothelial cell loss recorded at 1, 2, 3, and 4 years were compared with the Mann-Whitney U test.
Percentage ECD declines were calculated at each time point from the results of the preoperative and postoperative specular microscopy. Patients with graft rejection episodes and late endothelial failure were identified. Graft rejection was defined as findings of keratic precipitates with or without corneal edema, or anterior chamber cell and flare with or without corneal edema after the initial resolution of perioperative inflammation.
We identified 45 cases of graft rejection. The greatest number of rejections occurred between postoperative months 12 and 18. Eyes with a graft rejection episode had a higher median percentage decline in ECD at all time points compared with eyes without graft rejection episodes. This was statistically significant at 2 and 3 years postoperatively.
There is a trend toward a greater percentage of ECD loss with time in eyes experiencing graft rejection after DSAEK surgery.
Proprietary or commercial disclosure may be found after the references.
To report the 6-month results for the treatment of endothelial dysfunction in a large, prospective series of deep lamellar endothelial keratoplasty (DLEK) procedures.
Prospective, noncomparative, ...interventional case series.
One hundred eyes of 88 patients with corneal edema from Fuchs' dystrophy and pseudophakia.
A limbal, scleral, partial-depth incision provided access for a deep lamellar corneal pocket dissection. Two eyes were converted to penetrating keratoplasty (PK) at the time of DLEK surgery because of poor dissections. Of the 98 eyes that had completed DLEK surgeries, 36 eyes received a large-incision technique (9-mm scleral access incision) and 62 eyes received a small-incision technique (5-mm scleral access incision). A 7.5- to 8.0-mm posterior lamellar disc of recipient tissue then was excised and replaced through the pocket with a similar size donor disc containing healthy endothelium. A temporary air bubble in the anterior chamber was used for donor tissue adherence, and no surface corneal incisions or sutures were necessary.
Preoperative and postoperative best spectacle-corrected visual acuity (BSCVA), manifest refraction (MR) astigmatism, and endothelial cell density (ECD) were evaluated prospectively.
At 6 months after surgery, all 98 DLEK corneas were clear and the grafts were healed in good position. The mean BSCVA was 20/46, with a range between 20/20 and 20/400. The average MR astigmatism was 1.34+/-0.86 diopters (D), representing an average change in astigmatism from before surgery of +0.28+/-1.08 D (P = 0.013). The average ECD at 6 months was 2140+/-427 cells/mm2, representing a mean cell loss from preoperative donor cell measurements of 25%.
The DLEK procedure, with its absence of corneal surface incisions and sutures, preserves the normal corneal topography, minimizes astigmatism, and provides a healthy donor endothelial cell count and function. The DLEK procedure represents a reasonable alternative to PK, and compared with historical PK data, offers superior refractive outcomes in the treatment of endothelial dysfunction.
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 with the placement of another bubble postoperatively (with a 14.4% rebubble rate). Of those 16 cases, 2 required a second rebubble. Endothelial cell loss at 3 and 6 months postoperatively was 26.7% (n = 63 eyes) and 30.9% (n = 67 eyes), respectively.
This is the first report of the clinical use of prestained, preloaded tissue for DMEK. The characteristics and handling of the tissue were not different from those of surgeon-loaded tissue. Because punching, staining, and loading the graft intraoperatively is not necessary, the surgery time and risk of damaging donor tissue are reduced when using preloaded tissue.
With the success of Descemet's stripping automated endothelial keratoplasty (DSAEK) technique providing better outcomes in visual prognosis and theoretically lower rejection rate than penetrating ...keratoplasty, DSAEK dominated the realm of endothelial keratoplasty for the past decade. However, Descemet's membrane endothelial keratoplasty (DMEK) has become more and more popular worldwide due to its even lower rejection rate, faster visual recovery, better visual outcome, and lower long-term endothelial loss. In this article, we demonstrate the techniques and nuances of DMEK surgery in detail for corneal specialists who are beginning their DMEK surgeries.
To examine endothelial cell damage and stain retention of prestained preloaded Descemet membrane endothelial keratoplasty (DMEK) grafts.
DMEK grafts were stained with trypan blue or left unstained ...before loading into a Straiko modified Jones tube. A protocol to stain preloaded grafts inside the modified Jones tube and resulting cell loss was also examined. Endothelial cell loss was determined by vital dye staining after 3 days of cold storage and compared between the 3 groups. Eight additional grafts were stained, loaded, and shipped from Oregon to New York to assess stain stability. Stain retention and the ability to successfully inject and open these "prestained preloaded" grafts in cadaveric donor eyes were also evaluated.
Unstained preloaded DMEK grafts showed an overall cell loss of 15% ± 3% 95% confidence interval (CI), 11%-18%. Prestained grafts had a cell loss of 16% ± 4% (95% CI, 10%-22%) and were not significantly different from unstained grafts (P = 1). Grafts stained while inside the modified Jones tubes had an average cell loss of 18% ± 2% (95% CI, 16%-20%, Pprestained = 0.15, Punstained = 0.09). All grafts shipped across the country and examined 3 days after preparation showed a decrease in stain intensity but were still deemed suitable for transplantation by an experienced DMEK surgeon.
It is possible to prestain and preload DMEK grafts without inducing additional endothelial cell loss. Consideration should be given to the interval between staining and surgery because stain can fade.
To determine if donor graft diameter has a relationship with postoperative central endothelial cell density (ECD) and survival in Descemet's stripping automated endothelial keratoplasty (DSAEK).
...Retrospective, comparative analysis of an interventional case series.
Three hundred thirty-one eyes of 243 patients undergoing DSAEK surgery for Fuchs' endothelial dystrophy without a history of rejection or graft dislocation.
Descemet's stripping automated endothelial keratoplasty was performed in 331 eyes with Fuchs' dystrophy. After exclusion of confounding variables, postoperative ECD and percentage cell loss was compared for 8.0-mm grafts (n = 154) versus 8.5-mm grafts (n = 165) over a 2-year postoperative period.
Total central ECD and percentage of donor endothelial cell loss as measured by specular microscopy of central ECD.
Mean preoperative ECD was 2635 cells/mm(2) for 8.0-mm grafts and 2732 cells/mm(2) for 8.5-mm grafts (P = 0.003). Mean ECD (and percent cell loss from before surgery) was 2011 cells/mm(2) (22.9%) for 8.0-mm grafts and 2078 cells/mm(2) (23.5%) for 8.5-mm grafts at 6 months, 2009 cells/mm(2) (23.3%) and 2113 cells/mm(2) (23.1%) at 1 year, and 2060 cells/mm(2) (23.4%) and 2111 cells/mm(2) (24.3%) at 2 years (P>0.72 for percentage cell loss at all time points).
Descemet's stripping automated endothelial keratoplasty grafts with a diameter of 8.5 mm do not offer a clinical advantage over smaller 8.0-mm grafts for postoperative endothelial cell counts in the first 2 years after surgery.
Proprietary or commercial disclosure may be found after the references.
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