Safety analysis and results of a borosilicate glass cartridge for no-touch graft loading and injection in Descemet membrane endothelial keratoplasty.

PURPOSE: The aim of this study was to investigate the clinical outcome after standardized DMEK using a glass injector. METHODS: A total of 254 patients undergoing DMEK surgery using a disposable DMEK borosilicate glass cartridge system were included in this retrospective study. The mean follow-up time was 13.2 months (SD ± 8.1, range 6-36 months). The used glass cartridge system has an aperture diameter of 1.6 mm and a posterior loading orifice of 4.29 mm. Scanning electron microscopy (SEM) was used for estimation of the surface relief of the glass cartridge and comparison with a standard plastic injector cartridge. RESULTS: Mean endothelial cell count of donor grafts was 2465 cells/mm2 (SD ± 199). After 6 weeks of DMEK endothelial cell count decreased by - 28.6% to 1759 cells/mm2 (SD ± 435) (Wilcoxon p = 0.001) and remained stable at the final follow-up at 1735 cells/mm2 (SD ± 442) (Wilcoxon p = 0.89). SEM showed smoother surface of the glass cartridge in comparison with a plastic cartridge. CONCLUSION: This study showed that this simple and effective DMEK cartridge seems to be a safe and viable device for minimized graft manipulation during DMEK surgery.

Ultrathin descemet's stripping automated endothelial keratoplasty with the microkeratome double-pass technique: two-year outcomes.

PURPOSE: To evaluate the outcomes and graft survival rates after ultrathin (UT) Descemet's stripping automated endothelial keratoplasty (DSAEK) using the microkeratome-assisted double-pass technique. DESIGN: Prospective, consecutive, interventional case series. PARTICIPANTS: Patients with endothelial decompensation of various causes (Fuchs endothelial dystrophy, pseudophakic or aphakic bullous keratopathy, failed previous graft, herpetic endotheliitis, or buphthalmus; n = 285 grafts). INTERVENTION: Donor preparation was performed using the microkeratome-assisted double-pass technique. Stripping of the Descemet's membrane was performed under air and the graft was delivered into the anterior chamber using the pull-through technique through a 3-mm clear-cornea incision using a modified Busin glide. MAIN OUTCOME MEASURES: Best spectacle-corrected visual acuity (BSCVA), manifest refraction, endothelial cell density, and graft thickness (GT). RESULTS: Excluding all eyes with pre-existing ocular comorbidities, mean BSCVA at 3, 6, 12, and 24 months was 0.16, 0.11, 0.08, and 0.04 logarithm of the minimum angle of resolution units, respectively. The percentage of patients achieving BSCVA of 20/20 or better at 3, 6, 12, and 24 months was 12.3%, 26.3%, 39.5%, and 48.8%, respectively. A statistically significant (P < 0.0001) hyperopic shift of 0.78 ± 0.59 diopters (D; range, -0.75 to 1.75 D) was found at 1 year. The endothelial cell loss at 3, 6, 12, and 24 months was 29.8 ± 14.3%, 33 ± 15.5%, 35.6 ± 14.1%, and 36.6 ± 16.0%, respectively. The mean central GT recorded 3 months after surgery was 78.28 ± 28.89 µm. Complications included microkeratome failure to achieve perfect dissection in 21 donor tissues (7.2%), with 6 (2.1%) being discarded; total graft detachment in 11 cases (3.9%); primary failure in 4 cases (1.4%); and secondary failure in 4 additional cases (1.4%). Kaplan-Meier cumulative probability of a rejection episode at 3, 6, 12, and 24 months was 0%, 0.4%, 2.4%, and 3.3%, respectively. CONCLUSIONS: The visual outcomes of UT DSAEK are comparable with those published for Descemet's membrane endothelial keratoplasty and better than those reported after DSAEK in terms of both speed of visual recovery and percentage of patients with 20/20 final visual acuity. However, unlike with Descemet's membrane endothelial keratoplasty, preparation and delivery of donor tissue are neither difficult nor time consuming. Complications of UT DSAEK do not differ substantially from those recorded with standard DSAEK but are much less frequent than those reported after Descemet's membrane endothelial keratoplasty. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

[Posterior lamellar keratoplasty with DSEK technique and use of the Tan EndoGlide - short-term results]. / Keratoplastyka warstwowa tylna technika DSEK z zastosowaniem Tan endoGlide - wczesne doswiadczenia wlasne.

PURPOSE: To present the differences in surgical technique of DSEK (Descemet's Stripping Endothelial Keratoplasty) with the use of Tan EndoGlide (Coronet, UK) and Busin Glide (Moria, FR). Short-term results will also be presented, MATERIAL AND METHODS: DSEK was performed in 24 eyes, in 8 cases the surgery was combined with cataract phacoemulsification and lOL implantation. Surgery course and 6 months postoperative results of first 12 eyes performed with the use of Tan EndoGlide were compared with 12 consecutive eyes preformed with Busin Glide. RESULTS: Tan EndoGlide provided much more stable anterior chamber, donor tissue unfolding process was better controlled but the incision was wider incision. Surgically induced mean refractory cylinder 6. months after the surgery was 1.56 - 1.15 Dsph in Tan EndoGlide group and 1.18 +/- 1.10 Dsph in Busin Glide group (P <0.05). The endothelial cell loss was 20.5% and 21.12% respectively (P>0.05). Mean CDVA was 0.65+/- 0.27 and 0.63 +/- 0.25, respectively (P>0,05). Statistically significant differences in intra- and post-operative complications between both groups were not found. CONCLUSIONS: The Tan EndoGlide used during posterior lamellar keratoplasty with DSEK technique is a good alternative to currently used methods. It provides better stabilization of the anterior chamber, however its use is linked with higher postoperative astigmatism in comparison with Busin Glide. The visual outcomes and endothelial cell loss 6 months after the surgery were similar in both groups.

Irregularity of the posterior corneal surface during applanation using a curved femtosecond laser interface and microkeratome cutting head.

PURPOSE: To evaluate the irregularity of the posterior corneal surface and intrastromal dissection during the preparation of donor tissue for Descemet stripping automated endothelial keratoplasty (DSAEK) using a curved interface femtosecond laser and microkeratome. METHODS: Sixteen human donor corneas unsuitable for transplantation were divided into two groups: a femtosecond (FS) laser group (n=7) using the VisuMax femtosecond laser (Carl Zeiss Meditec) and a microkeratome group (n=9) using the Amadeus II microkeratome (Ziemer Ophthalmic Group). The corneas were fixed on artificial anterior chambers. Horizontal cross-sections were obtained using spectral-domain optical coherence tomography prior to applanation, during applanation, as well as during and after intrastromal dissection at 450-µm corneal depth. The posterior surface and the dissection line were evaluated for irregularity by fitting a second-order polynomial curve using regression analysis and obtaining the root-mean-square error (RMSE). Groups were compared using analysis of variance. RESULTS: The RMSE of the posterior surface prior to applanation was 9.7 ± 3.1 µm in the FS laser group and 10.2 ± 2.3 µm in the microkeratome group. The RMSE increased to 50.7 ± 9.4 µm and 20.9 ± 6.1 µm during applanation and decreased again to 10.6 ± 1.4 µm and 8.1 ± 1.8 µm after applanation in the FS laser and microkeratome groups, respectively. The RMSE of the intrastromal cut was 19.5 ± 5.7 µm in the FS laser group and 7.7 ± 3.0 µm in the microkeratome group (P<.001). CONCLUSIONS: Our results show significantly greater irregularity with the curved interface femtosecond laser-assisted cleavage compared to microkeratome-assisted corneal dissection, possibly due to applanation-derived deformation of the posterior cornea.

[Precut technique for Descemet's membrane endothelial keratoplasty, preparation and storage in organ culture]. / Precut Verfahren für Descemet-Membran-Endothelzelltransplantation, Präparation und Aufbewahrung in Kultur.

BACKGROUND: The preparation of the Descemet's membrane (DM) with the endothelial cell layer may be performed directly prior to surgery or as a precut tissue procedure. The purpose of the current study was the evaluation of the preparation technique and the tissue culture of 10 days regarding potential endothelial cell loss. MATERIALS AND METHODS: Ten corneoscleral rims with an average age of 64.3 years were dissected to obtain 8.5 mm in diameter endothelial-DM complexes, which subsequently were organ cultured for 10 days. The endothelial cell density (ECD) was assessed during the cell culture period at days 1., 4., 7. and 10. In addition, time of preparation and transplant morphology were evaluated. RESULTS: The DM with the endothelial cell layer could successfully be dissected from all corneoscleral rims. The average preparation time was 8.3 min. The average ECD count was 2183 ± 77 cells/mm2 prior to, 2094 ± 110 cells/ mm2 at day 1, 2078 ± 134 cells/mm2 at day 4, 1977 ± 107 cells/mm2 at day 7 and 1898 ± 170 cells/mm2 at day 10 after preparation, respectively. Endothelial cell loss was 4.1 %, 4.8 %, 9.4 % and 13.1 % after preparation, respectively. None of the transplants exhibited large, centrally-located cell deficits. CONCLUSION: The isolated storage of DM with the endothelial layer, without any stromal remnants, showed gratifying results under storage conditions in organ culture with a moderate ECD decrease. Hence, the implementation of a precut DMEK is conceivable.

Evaluation of Efficacy, Efficiency, and Cell Viability of a Novel Descemet Membrane Endothelial Keratoplasty Graft Preparation Device, DescePrep, in Nondiabetic and Diabetic Human Donor Corneas.

PURPOSE: The purpose of this study was to evaluate the safety, efficacy, and efficiency of a Descemet membrane endothelial keratoplasty (DMEK) graft preparation device, DescePrep, through measurement of graft viability, yield, and preparation time in both healthy and diabetic (high-risk) donor eyes. METHODS: Twenty nondiabetic and 10 diabetic donor corneas were processed using DescePrep, which standardizes the liquid bubble technique. Corneas were stained with trypan blue and then processed. Cell counts through specular microscopy, optical coherence tomography imaging, and slit-lamp analysis were used for the evaluation of graft separation and viability in 5 nondiabetic corneas. The remaining 25 corneas (15 nondiabetic and 10 diabetic) were evaluated for preparation success rate and processing time. Ten corneas (5 nondiabetic and 5 diabetic) were randomly selected for further evaluation of global cell loss through staining. RESULTS: Ninety-seven percent of corneas (29 of 30) were prepared successfully with DescePrep. The average preparation time was 2.83 ± 1.8 minutes. There was no significant difference in the time of preparation between the nondiabetic and diabetic groups (P = 0.077). The overall average cell death after processing was 7.9% ± 3.7% for all corneas. There was no significant difference in cell viability between diabetic and nondiabetic tissues after DescePrep processing (P = 0.769). CONCLUSIONS: DescePrep is a new DMEK preparation technique that can process both nondiabetic and diabetic donor corneas at high yields in minutes. High-yield preparation of diabetic corneas may offer eye banks access to a larger donor pool, which is important because the demand for DMEK grafts continues to rise worldwide.

Preloaded Descemet Membrane Endothelial Keratoplasty Grafts With Endothelium Outward: A Cross-Country Validation Study of the DMEK Rapid Device.

PURPOSE: To validate the "Descemet membrane endothelial keratoplasty (DMEK) Rapid" device for the cross-country transportation of preloaded DMEK grafts preserved with endothelium outward. METHODS: DMEK grafts were stripped and loaded in the DMEK Rapid device with tissue culture medium (TCM) or transport medium (TM) with endothelium outward. The device was mounted in a 40-mL flask and preserved for 4 days on a rocker to simulate transportation (study A, n = 24) or shipped in the TM from Italy to the United Kingdom (study B, n = 9) and evaluated within 72 hours. All the tissues were stained with Alizarin red. Viability of the cells was checked postsimulations and posttransportation and was confirmed using live/dead staining. Expression of tight junction proteins was evaluated. RESULTS: In study A, the endothelial cell loss observed from the TCM group was 20.8% (±5.2) compared with 19.5% (±6.7) from the TM group (P = 0.41) after transport simulation. Alizarin red showed minimal uncovered areas in both groups. There were no statistical differences in viability between the TM (80.83%) and TCM groups (78.83%). In study B, 12.9% (±7.8) endothelial cell loss was observed after transporting the tissues from Italy to the United Kingdom with no significant difference between prestrip and posttransportation (P = 0.05). Alizarin red staining did not show any uncovered area. Live/dead analysis showed 85.16% cell viability after transportation. zonula occludens-1 (ZO-1) was expressed in all tissues. CONCLUSIONS: The DMEK Rapid device is safe for preloading and shipping DMEK grafts internationally with endothelium outward within 72 hours when preserved in the transport media.

[Clinical study of Descemet membrane stripping with automated endothelium keratoplasty].

OBJECTIVE: To investigate the clinical efficacy, prevention and management complications and choice of indication with Descemet membrane stripping with automated endothelium keratoplasty (DSAEK). METHODS: Clinical case series. Nine patients (9 eyes) with bullous keratopathy underwent DSAEK procedure from Peking University Eye Center, Peking University Third Hospital during September to December in 2007. Visual acuity, cornea transparency, graft position, corneal thickness, curvature, astigmatism and endothelial cells density (ECD) were observed over 3-7 month follow-up period. RESULTS: One patient with iris cornea endothelium syndrome was fail to insert graft into anterior chamber and changed procedure to penetrating keratoplasty. Eight patient successfully performed procedure. One graft dislocation in was managed in first day after surgery. All 8 grafts remained transparent and improved visual acuity. After surgery, mean corneal thickness was (775 +/- 30)microm. Mean corneal curvature was (44.19 +/- 2.28) D. Mean corneal astigmatism was (2.20 +/- 0.83) D. Mean endothelial cells density was (1439 +/- 296) cells/mm(2). CONCLUSIONS: DSAEK is a less damage, faster recovery vision, safer procedure. It is expected to be the important procedure to treat bullous keratopathy.

[Effect of temporary anchor sutures on Descemet stripping endothelial keratoplasty in aphakic eyes].

OBJECTIVE: To investigate the feasibility, efficacy, and complications of the temporary anchor sutures for endothelial graft fixation in Descemet stripping endothelial keratoplasty (DSEK) in aphakic eyes. METHODS: Non-randomized retrospective case series. Twelve consecutive cases (12 eyes) with aphakic bullous keratopathy underwent DSEK using the temporary anchor sutures technique for fixation of donor button in Zhongshan Ophthalmic Center between April to December in 2007. All cases were resulted from lens extraction and best spectacle-corrected visual acuity (BSCVA) was inferior or equal to 0.04. Eight cases were with preoperative pain. Prospective data of BSCVA, corneal astigmatism, curvature and thickness were collected on all 12 eyes preoperatively and at 3, 6 and 12 months postoperatively. Average endothelial cell density (ECD) and endothelial cell loss (ECL) were recorded at 6 and 12 months postoperatively. The follow-up period was 12 to 20 months. RESULTS: All cases were performed DSEK successfully using the temporary anchor sutures and the grafts were well-attached without dislocation. On postoperative day 1, papillary block glaucoma occurred in 2 eyes and mannitol 20% was administered intravenously. The intraocular pressure in the 2 eyes returned to normal due to the air bubble absorption on postoperative day 2. The endothelial grafts showed mild to moderate edema in all eyes and became clear in 8 to 15 days postoperatively. All the corneas were clear during follow-up. In 12 months postoperatively, BSCVA was 0.7 in 16.7% of eyes (n = 2), 0.5 in 25.0% of eyes (n = 3), 0.4 in 33.3% of eyes (n = 4), and 0.3 in 25.0% of eyes (n = 3); mean corneal astigmatism was (2.40 + or - 0.70) diopters, mean corneal curvature was (45.40 + or - 1.50) diopters, and mean corneal thickness was (591.5 + or - 20.4) microm. Mean endothelial cell density (ECD) was (2088 + or - 146) cells/mm(2) [(28.9 + or - 3.9)% endothelial cell loss] and (1857 + or - 101) cells/mm(2) [(36.7 + or - 3.1)% endothelial cell loss] in 6 and 12 months postoperatively, respectively. CONCLUSION: The temporary anchor sutures technique was easy to perform and effectively prevented graft dislocation and detachment into the vitreous cavity.

Quantitative and Qualitative Differences in Endothelial Cell Loss Between Endothelium-In Versus Endothelium-Out Loading in Descemet Membrane Endothelial Keratoplasty.

PURPOSE: This study compares endothelial cell loss (ECL) between donor grafts loaded in the Geuder Glass Cannula and the Coronet EndoGlide made specifically for Descemet membrane endothelial keratoplasty (DMEK). METHODS: Prestripped tissues using the submerged cornea using backgrounds away (SCUBA) technique were obtained from an eye bank. Donor grafts were loaded with the Geuder Glass Cannula or Coronet DMEK EndoGlide. Grafts were then ejected directly onto a glass slide, stained, and imaged with confocal fluorescent microscopy. Trainable Fiji (ImageJ) segmentation software was used to quantify ECL. RESULTS: Twenty-three total tissue samples were tested. Eleven grafts were loaded using the Geuder, and 12 were loaded with the Coronet. Preloading graft endothelial cell density was comparable between Geuder (2436 ± 581 cells/mm) and Coronet (2577 ± 483 cells/mm) groups with P = 0.56. Other baseline characteristics including donor age and time from death to loading were comparable (P = 0.73 and P = 0.66, respectively). Average ECL was 11.3% ± 3.0% in the Geuder group versus 7.2% ± 7.0% in the Coronet group and not significantly different (P = 0.07). When observing patterns of cell loss, grafts loaded in the Coronet DMEK EndoGlide resulted in more focal forceps grabs and trifold patterns. Grafts loaded with the Geuder Glass Cannula yielded more diffuse stippled stress lines. CONCLUSIONS: Our results suggest comparable ECL between Geuder (endothelium-out) and Coronet (endothelium-in) DMEK EndoGlide tissue injection techniques. Patterns of ECL in the Coronet group correlated with forceps grabs, but this study suggests that additional manipulation of tissue does not result in higher ECL.

Clinical Evaluation of the "Lifeline Suture" Technique for DSAEK in Cases Without Posterior Capsule Using a Novel Donor Insertion Device.

PURPOSE: This study investigated preliminary clinical outcomes of a suture pull-through technique for Descemet stripping automated endothelial keratoplasty (DSAEK) termed the "lifeline suture" technique using a newly developed donor inserter (NS Endo-Inserter: NSI; Hoya Co, Ltd, Tokyo, Japan) in cases of bullous keratopathy without posterior capsule. METHODS: Six aphakic eyes without posterior capsule from 6 patients (mean age 73.8 ± 11.9 years) with bullous keratopathy were enrolled. DSAEK alone or as a vitreocorneal surgery was performed. Donor tissue was pulled into the anterior chamber using the NSI and a 9-0 polypropylene "lifeline suture" to prevent donor tissue from slipping into the vitreous cavity, which was removed at the end of surgery. Intraoperative and postoperative complications and 6-month postoperative central donor endothelial cell densities were measured and compared with preoperative values along with 6-month best-corrected visual acuity. RESULTS: All donors were successfully loaded into the NSI and then pulled into the anterior chamber using the lifeline suture. No intraoperative complications, graft dislocation, or primary graft failures were noted. Six months postsurgery, mean endothelial cell density was 2027 ± 747 cells/mm (mean loss 27.2 ± 28.1%) and mean best-corrected visual acuity improved to 0.31 decimal (P = 0.018). CONCLUSIONS: In this preliminary case series of bullous keratopathy without posterior capsule, DSAEK outcomes using the novel NSI donor inserter with lifeline suture were comparable or better than the results expected with conventional strategies. Thus, this technique enabled apparently safe DSAEK, preventing donor migration into the vitreous cavity while maintaining a stable anterior chamber, and is suitable for complex eyes including aphakia, lacking posterior capsule, or avitreal.

Descemet Membrane Endothelial Keratoplasty With a Pull-Through Insertion Device: Surgical Technique, Endothelial Cell Loss, and Early Clinical Results.

PURPOSE: To describe a surgical technique for Descemet membrane endothelial keratoplasty (DMEK) using a pull-through, endothelium-in insertion device, the DMEK EndoGlide. We evaluated the endothelial cell loss (ECL) associated with the EndoGlide-DMEK (E-DMEK) technique in both ex vivo and prospective clinical studies. METHODS: The ex vivo study involved calcein acetoxymethyl staining and preparation of DMEK grafts, which were trifolded endothelium-in, loaded into the EndoGlide, pulled through, and unfolded in imaging dishes. Inverted fluorescent microscopy was performed, and ECL was quantified using trainable segmentation software. The prospective clinical series describes the outcomes of consecutive surgeries using the E-DMEK technique. Grafts were pulled through the EndoGlide with forceps and unfolded in the anterior chamber endothelium-down. Our main outcome measure was ECL in both studies. RESULTS: In the ex vivo study with 9 human donor corneas, mean ECL was 15.2% ± 5.4% (n = 9). In our clinical series of 69 eyes, leading indications for surgery were pseudophakic/aphakic bullous keratopathy (47.8%), previous failed grafts (23.2%), and Fuchs endothelial dystrophy (18.8%). Rebubbling and primary graft failure rates related to E-DMEK were 11.6% and 1.5%, respectively. Among eyes with at least 6 months of follow-up, mean preoperative endothelial cell density was 2772 (range 2457-3448) cells/mm, and postoperative endothelial cell density was 1830 (range 541-2545) cells/mm. Mean ECL was 33.6% (range 7.5-80.4; n = 32) at the 7.1 (range 6-11) months follow-up. CONCLUSIONS: The ex vivo and pilot clinical studies suggest that E-DMEK shows acceptable rates of ECL, with safe and promising early clinical outcomes.

Hybrid Descemet Membrane Endothelial Keratoplasty (H-DMEK): results of a donor insertion pull-through technique using donor stroma as carrier.

AIM: To evaluate the outcomes and complications of hybrid Descemet membrane endothelial keratoplasty (H-DMEK) using a Descemet stripping automated endothelial keratoplasty (DSAEK) pull-through donor inserter and donor stroma as carrier. METHODS: This was a retrospective interventional case series of eyes with bullous keratopathy (BK) and Fuchs endothelial corneal dystrophy (FECD), which underwent H-DMEK, performed using a bimanual pull-through technique using DSAEK-prepared donor stroma as carrier and the EndoGlide Ultrathin DSAEK donor insertion device. Complex cases with tube shunts, trabeculectomy, aphakia, aniridia, previous vitrectomy, keratoplasty or combined with intraocular lens exchange, were also included. The outcome measures were intraoperative and postoperative complications, best corrected visual acuity (BCVA) and endothelial cell loss after surgery. RESULTS: Of the 85 eyes from 79 patients, 43.5% (n=37) had BK, 28.2% (n=24) had FECD while 24.7% (n=21) had failed grafts. DMEK was performed in 37 complex eyes (43.5%). Four eyes (4.7%) required rebubbling for graft detachment and two cases of graft failure were observed. A BCVA of 20/25 or better was attained in 44.7% and 57.1% of eyes without pre-existing ocular pathology at 6 and 12 months, respectively. The overall endothelial cell loss was 32.2%±20.5% at 6 months, which improved from 37.2%±20.9% to 24.2%±17.5%, comparing the first 40 and last 45 cases (p=0.012). CONCLUSION: Hybrid DMEK offers a controlled 'pull-through' technique of donor insertion in the 'endothelium-in' configuration, which may be useful especially in complicated eyes. More studies are needed to confirm the long-term endothelial cell loss and graft survival associated with this technique.

[DSAEK for the treatment of endothelial disease: results in the initial 100 cases]. / DSAEK für die chirurgische Behandlung der Endotheldekompensation: Ergebnisse der ersten 100 Fälle.

PURPOSE: To evaluate the learning curve and the outcome of Descemet Automated Endothelial Keratoplasty (DSAEK) in patients with primary or secondary endothelial decompensation. METHODS: DSAEK was performed in 100 eyes with endothelial decompensation (Fuchs' Dystrophy n = 59; pseudophakic bullous keratopathy n = 33; failed corneal graft n = 8). All patients underwent a standard procedure including the following steps: Descemet membrane and endothelium removal from the recipient cornea under air; inferior peripheral iridectomy; microkeratome-assisted preparation of a donor lamella consisting of deep stroma and endothelium (between 100 and 200 micron in thickness), which is punched to desired size (8.5 to 9 mm) from the endothelial side; graft delivery with a specially designed glide; complete anterior chamber air fill to obtain firm attachment of the donor lamella and air-tight closure of all surgical wounds. In 46 cases phacoemulsification with implantation of an intraocular lens into the capsular bag was combined with DSAEK surgery. Visual acuity, refraction and endothelial cell count were evaluated prospectively at 1, 3, 6, and 12 months after DSAEK. RESULTS: As early as 1 month after surgery 76 of 100 patients had a best spectacle-corrected visual acuity (BSCVA) better than or equal to 0.5, with a refractive astigmatism within 1.5 Diopters (D). One year after surgery, 79 of 100 patients had a BSCVA better than or equal to 0.5, with a refractive astigmatism within 1.5 D. At this examination time 11 of 100 patients could see 1.0 or better and the average endothelial cell loss amounted to 22.5 +/- 4.2 %. CONCLUSIONS: DSAEK surgery allows fast visual rehabilitation of patients with decompensated endothelium. Visual outcome is superior to that of conventional penetrating keratoplasty (PK) in terms of BSCVA and early stabilization. Endothelial cell loss also compares favourably to that recorded after PK.

Effect of Air Injection Depth on Big-bubble Formation in Lamellar Keratoplasty: an Ex Vivo Study.

This study evaluated the effect of air injection depth in the big-bubble (BB) technique, which is used for corneal tissue preparation in lamellar keratoplasty. The BB technique was performed on ex vivo human corneoscleral buttons using a depth-sensing needle, based on optical coherence tomography (OCT) imaging technology. The needle tip, equipped with a miniaturized OCT depth-sensing probe, was inserted for air injection at a specified depth. Inside the corneal tissue, our needle obtained OCT line profiles, from which residual thickness below the needle tip was measured. Subjects were classified into Groups I, II, III, and IV based on injection depths of 75-80%, 80-85%, 85-90%, and >90% of the full corneal thickness, respectively. Both Type I and II BBs were produced when the mean residual thicknesses of air injection were 109.7 ± 38.0 µm and 52.4 ± 19.2 µm, respectively. Type II BB (4/5) was dominant in group IV. Bubble burst occurred in 1/16 cases of type I BB and 3/16 cases of type II BB, respectively. Injection depth was an important factor in determining the types of BBs produced. Deeper air injection could facilitate formation of Type II BBs, with an increased risk of bubble bursts.

Microkeratome-assisted ultrathin Descemet's stripping automated endothelial keratoplasty: A randomized trial comparing single-pass versus double-pass technique.

Purpose: To compare the outcomes of two techniques, for preparation of microkeratome-assisted ultrathin grafts for Descemet's stripping automated endothelial keratoplasty (DSAEK). Methods: The study involved 20 eyes of 20 patients with pseudophakic bullous keratopathy, randomized into two groups. Group 1 eyes underwent microkeratome-assisted DSAEK using the single-pass technique for lenticule preparation, whereas group 2 eyes underwent microkeratome-assisted DSAEK using the double-pass technique. Patients were followed up till 6 months, postoperatively. Best-corrected visual acuity (BCVA) at final follow-up was considered as the primary outcome measure, whereas graft thickness (GT) contrast sensitivity and endothelial cell loss were considered as the secondary outcome measures. A P value of <0.05 was considered as statistically significant. Results: Baseline characteristics of two groups were comparable. The mean central GT was comparable in both groups at 6 months follow-up [group 1: 98 ± 24.46 µm, group 2: 129 ± 31.46 µm (P = 0.18)]. Both groups fared equally in terms of BCVA (P = 0.33). Contrast sensitivity was significantly better in group 1 eyes (P = 0.045). A statistically significant negative correlation was found between postoperative BCVA and postoperative GT (R = -0.728, P = 0.016). The percentage endothelial cell loss was slightly higher in group 2 eyes, although not statistically significant. Two eyes in group 2 experienced complications during lenticule preparation. None of the eye experienced any complication in the postoperative period. Conclusion: Both techniques provided grafts with comparable thickness and endothelial cell loss and were associated with comparable BCVA, at final follow-up visit. The contrast sensitivity was, however, better in eyes receiving grafts prepared with the single-pass technique.

Safety of Long-Term Storage and Shipping of Prestripped, Prestained, and Preloaded Descemet Membrane Endothelial Keratoplasty Tissue.

PURPOSE: The purpose of this study was to determine the safety of long-term storage and shipping of prestripped, prestained, and preloaded Descemet membrane endothelial keratoplasty (pDMEK) grafts. METHODS: A total of 33 cadaveric corneas were prestripped, prestained, and preloaded using modified Jones tube injectors as pDMEK. The corneas were masked to groups that were prepared <9 hours (control), 48 hours, and 72 hours before unloading and analysis. The 48- and 72-hour tissues were shipped by airfreight on each day before arrival to simulate domestic and international shipping. The corneas were then stained using Calcein AM vital dye (Molecular Probes, Eugene, OR) and imaged using an inverted confocal microscope. Primary outcome measures were endothelial cell loss (ECL, %) and sustainability of staining. MetaMorph software (Molecular Devices, Downingtown, PA) was used to quantify ECL, and staining was evaluated subjectively using all-or-none rating. RESULTS: There was no difference in the mean ECL for the control, 48-hour, and 72-hour groups, which were 25.1% ± 8.8%, 26.4% ± 17.5%, and 19.2% ± 11.5%, respectively (P = 0.45; Kruskal-Wallis test). In all tissues of each group, no loss of staining was identified at each time point of analysis. CONCLUSIONS: ECL in pDMEK tissue prepared 48 and 72 hours in advance and shipped using standard methods is similar to that in pDMEK tissue prepared on the same day. These findings support the safety of domestic and international shipping of pDMEK grafts.

Comparison of endothelial cell loss and complications following DMEK with the use of three different graft injectors.

PurposeTo compare endothelial cell loss and complications following Descemet membrane endothelial keratoplasty (DMEK) with use of three commercially available injectors.MethodsFrom 179 consecutive DMEK procedures, 66 cases with uncomplicated graft preparation and completed 12-month follow-up were included in this retrospective study. According to the injector used, 3 groups were formed: group 1 (D.O.R.C. injector, n=16), group 2 (Geuder injector, n=24), and group 3 (Pasteur laboratory pipette, n= 26). Endothelial cell density (ECD) and endothelial cell loss were evaluated preoperatively and at 3, 6 and 12 months postoperatively; surgery-related complications were recorded.ResultsDonor ECD was 2416±179 cells/mm2 (group 1), 2417±164 cells/mm2 (group 2), and 2478±234 cells/mm2 (group 3). At 12 months postoperatively ECD was 1473±403 cells/mm2 (group 1), 1379±317 cells/mm2 (group 2), and 1316±456 cells/mm2 (group 3) (P=0.533, ANOVA). Endothelial cell loss 12 months postoperatively was 39±15% (group 1), 43±13% (group 2), and 47±17% (group 3) (P=0.386, ANOVA). A single case of iris bleeding and reflux of the graft out of the anterior chamber (both in group 3) was noted. Partial graft detachment occurred in group 1 (n=1), group 2 (n=5), and group 3 (n=7) and rebubbling was performed in 6% (group 1), 17% (group 2), and 27% (group 3).ConclusionsTo our knowledge, this is the first clinical study assessing the safety of three different DMEK injectors. Group 1 (D.O.R.C injector) showed the least and group 3 (Pasteur laboratory pipette) the highest endothelial cell loss without reaching statistical significance at 12 months after surgery. Therefore, the graft injector may be chosen according to surgeon's preference.

New Graft Insertion Device for Descemet Stripping Automated Endothelial Keratoplasty.

PURPOSE: Corneal endothelial dysfunction is a major indication for corneal graft surgery worldwide, and although surgical intervention through a range of posterior lamellar surgeries has proven to be hugely beneficial, challenges remain. This is especially so where the anterior chamber is relatively shallow, as is often the case in the Asian population, though not exclusively so. In this study, we introduce a new insertion device to deliver endothelial graft tissue for Descemet stripping automated endothelial keratoplasty (DSAEK). METHODS: A new surgical tool was designed and manufactured so as to enable a 1-step insertion of corneal graft tissue into the anterior chamber based on a pressure-flow concept, rather than the a pull-through one. This was tested ex vivo to assess endothelial cell damage, and then performed in 12 first-in-human surgeries. RESULTS: Precut DSAEK lenticules implanted in donor corneas ex vivo through the new technique showed that less endothelial cell damage occurs compared with a pull-through technique. Grafts were successful in all patients receiving the new surgery, with no cases of primary graft failure. CONCLUSIONS: The newly developed DSAEK inserter is a simple and useful tool for endothelial graft delivery, lessening intraoperative mechanical stress on the graft tissue.

Comparison of the Endosaver with noninjector techniques in Descemet's stripping endothelial keratoplasty.

PURPOSE: Minimal loss of corneal endothelial cells during corneal transplantation is a major target but remains a point of controversy among specialists. Hence, the available method to best achieve this continues to stir progress in the field. The aim of this study is to evaluate the use of the Endosaver injector device for graft insertion in Descemet's stripping endothelial keratoplasty (DSEK) and compare the visual outcomes and endothelial cell survival between the Endosaver injector and Goosey grasping forceps insertion techniques. METHODS: This was a retrospective, interventional, consecutive case series undertaken at the University of Southampton Eye Department to assess outcomes of DSEK using the Endosaver injector device compared to noninjector DSEK insertion. Postoperative specular microscopy alongside manifest refraction at 6 and 12 months was evaluated and compared. Mann-Whitney U-test was employed for the statistical analysis of data. RESULTS: Both the Endosaver and Goosey forceps groups showed an improvement in best corrected visual acuity. No significant statistical difference was found in preoperative and postoperative best-corrected visual acuity between the Endosaver and non-Endosaver insertion groups. Mean preoperative endothelial cell count was 2660 (±130) for the Endosaver group and 2608 (±66) for the non-Endosaver group. Postoperative endothelial counts at 6 and 12 months showed a significant difference between the Endosaver: 2104 (±199)-1896 (±226) and the non-Endosaver: 1492 (±207)-1314 (±224) (P < 0.005) groups, respectively. CONCLUSION: The Endosaver injection device is associated with less trauma to endothelium during graft insertion due to the minimal touch technique employed. A smaller insertion wound of 4.0 mm compared to noninjector cases enabled a more stable system during surgery with no or minimal anterior chamber shallowing. The combination of a stable host with minimal endothelial graft handling and subsequent trauma potentially leads to higher endothelial cell counts when the Endosaver injection device is used compared to forceps insertion.