Bowman Layer Onlay Grafting as a Minimally Invasive Treatment for the Most Challenging Cases in Keratoconus.

PURPOSE: To analyze the clinical outcomes after Bowman layer (BL) onlay grafting for the treatment of progressive, advanced keratoconus. DESIGN: Prospective, interventional case series. METHODS: Twenty-one eyes underwent BL onlay grafting. After removing the epithelium, a single or double BL graft was "stretched" onto the corneal surface, allowed to dry-in, and a soft bandage lens was placed until the graft was re-epithelialized. Best spectacle- and/or best contact lens-corrected visual acuity (BSCVA/BCLVA), corneal tomography, and postoperative complication rates were analyzed for the total group and 2 subgroups (group 1: preoperative maximum keratometry [Kmax] <69 diopters [D; n = 7); group 2: preoperative Kmax ≥69 D [n = 14]). Follow-up ranged from 6 to 36 months (mean 21 ± 11 months). RESULTS: All 21 surgeries were uneventful. Overall, Kmax changed from 76 ± 12 D preoperatively to 72 ± 9 D at 6 to 36 months postoperatively (P = .015). Kmax decreased by 6 D in group 2 (P = .002) but did not change in group 1. Average BSCVA remained stable for group 1 and improved from preoperatively 0.8 ± 0.4 to 0.4 ± 0.2 logarithm of the minimum angle of resolution postoperatively in group 2 (P = .032); BCLVA remained stable (P > .05). Within the first postoperative weeks, 2 eyes required BL graft repositioning after inadvertent bandage lens removal and 4 eyes underwent BL retransplantation for incomplete re-epithelialization. One eye underwent BL regrafting 12 months postoperatively after traumatic corneal erosion. All eyes showed a completely re-epithelialized graft at the last available follow-up. CONCLUSIONS: BL onlay grafting is a completely extraocular, minimally invasive surgical technique, providing up to -6 D of corneal flattening in eyes with advanced progressive keratoconus, allowing for continued (scleral) contact lens wear and therefore preserving the BCLVA.

Long-Term Outcomes of Descemet Membrane Endothelial Keratoplasty: Effect of Surgical Indication and Disease Severity.

PURPOSE: The aim of this study was to evaluate clinical outcomes and graft survival in a large patient cohort up to 10 years after Descemet membrane endothelial keratoplasty (DMEK) based on surgical indication and Fuchs endothelial corneal dystrophy (FECD) severity. METHODS: The cohort in this retrospective study included 750 eyes that underwent DMEK for FECD (86%), bullous keratopathy (BK, 9%), and other indications (5%). Based on the modified Krachmer grading, 186 eyes (29%) had moderate FECD (Krachmer grade 3-4) and 440 eyes (68%) had advanced FECD (Krachmer grade 5-6). Main outcome measures were best-corrected visual acuity (BCVA), central corneal thickness, endothelial cell density (ECD), endothelial cell loss (ECL), postoperative complication rate, and graft survival. RESULTS: The mean 10-year BCVA was 0.08 ± 0.28 logMAR (n = 96), and the BCVA remained stable between 5 and 10 years postoperatively (all P > 0.05). The mean ECL at 5 and 10 years was 56% ± 17% (n = 460) and 66% ± 14% (n = 96), respectively ( P < 0.05). The 10-year graft survival rate for the total cohort was 0.85 (95% confidence interval, 0.82-0.89). BCVA and ECD differed at 1 to 5 years between eyes with different surgical indications (all P < 0.05), and FECD eyes had higher graft survival compared with BK eyes (0.90 vs. 0.60, P = 0.001). Moderate FECD eyes had better BCVA, ECD, and graft survival outcomes than advanced FECD eyes (all P < 0.05). Minor graft detachment ( P = 0.04) and lower donor ECD ( P = 0.01) were related to lower 10-year ECD. CONCLUSIONS: Long-term outcomes and graft survival after DMEK were better in FECD eyes than BK eyes and were also related to FECD disease severity. Eyes operated for moderate FECD showed the highest graft survival probability and excellent long-term outcomes.

Impact of Fuchs Endothelial Corneal Dystrophy Severity on Scheimpflug-Derived Parameters After Descemet Membrane Endothelial Keratoplasty.

PURPOSE: The aim of this study was to evaluate how Scheimpflug-derived parameters of eyes with Fuchs endothelial corneal dystrophy (FECD) are influenced by Descemet membrane endothelial keratoplasty (DMEK) depending on FECD severity and the presence of subclinical edema. METHODS: A retrospective cohort study including 115 eyes (115 patients) that underwent DMEK for FECD and a control group of 27 eyes with nonpathological corneas was conducted. Preoperative and 6 months postoperative Scheimpflug imaging was used to analyze pachymetry, presence of tomographic features (loss of isopachs/displacement of the thinnest point/focal posterior depression), and corneal backscatter. FECD severity was based on the modified Krachmer scale and the absence/presence of subclinical edema. RESULTS: Scheimpflug-derived pachymetry, tomographic, and corneal backscatter parameters were correlated with FECD severity, and all changed from preoperatively to postoperatively (all P < 0.05). Postoperative central corneal thickness, anterior and posterior corneal backscatter, and presence of focal posterior depression remained different from the control group (all P < 0.05). Of eyes without preoperative clinical edema (n = 75), 18.7% showed 0 or 1 tomographic feature (no edema group) and 82.4% had 2 or 3 features (subclinical edema group). Compared with the control group, postoperative best-corrected visual acuity for the "no edema" group did not differ (0.03 ± 0.12 vs. -0.02 ± 0.08 logarithm of the minimum angle of resolution, P = 0.150) but was worse for the subclinical edema group (0.06 ± 0.08 vs. -0.02 ± 0.08 logarithm of the minimum angle of resolution, P = 0.001). CONCLUSIONS: For eyes without preoperative edema, more parameters reversed back to 'normal' levels than for eyes with (sub)clinical edema. Although most analyzed parameters correlated with FECD severity, corneal tomography might be best suited for objective grading of disease severity to aid in surgical decision-making.

[Evolution in corneal transplantation techniques]. / Evolutie in hoornvliestransplantatie.

Over the past twenty years, there have been many developments in the treatment of corneal diseases, especially in the field of corneal transplantation. By targeting treatments solely to the affected layers of the cornea, the procedures have become less invasive and the cornea recovers significantly faster. Despite the success of these new surgical techniques, new (cell) regenerative therapies are emerging.

Bowman Layer Onlay Graft for Recurrent Corneal Erosions in Map-Dot-Fingerprint Dystrophy.

PURPOSE: The purpose of this study was to describe a case with recurrent corneal erosions who was treated with a Bowman layer (BL) onlay graft. METHOD: BL onlay transplantation was performed. RESULTS: In a 79-year-old female patient who presented with bilateral map-dot-fingerprint dystrophy and a history of recurrent painful corneal erosions, BL onlay grafting was performed to restore the corneal surface. At 1 month postoperatively, the epithelium was smooth over the graft, and until 1.5 years postoperatively, the patients had no complaints and no recurrence of the epithelial corneal erosion. CONCLUSIONS: In the described case, the transplantation of an isolated BL graft as an onlay proved to be an effective treatment for painful chronic recurrent erosions in the context of map-dot-fingerprint dystrophy in a patient who had undergone numerous unsuccessful previous treatments.

Long-Term Outcomes of Bowman Layer Inlay Transplantation for the Treatment of Progressive Keratoconus.

PURPOSE: To report long-term clinical outcomes and estimated success rates after Bowman layer (BL) inlay transplantation in eyes treated for progressive keratoconus (KC). METHODS: Thirty-five eyes (29 patients) with progressive KC underwent BL inlay transplantation. Best-corrected spectacle and contact lens visual acuity, Scheimpflug-based corneal tomography [simulated and maximum keratometry (Kmax)], central corneal thickness, thinnest point thickness, complications, and success rate were evaluated up to 8 years postoperatively for the total group and 2 subgroups [group 1: preoperative Kmax > 69 diopter (D) (n = 26); group 2: preoperative Kmax < 69D (n = 9)]. RESULTS: Mean logarithm of the minimum angle of resolution best contact lens-corrected visual acuity for the total group and the 2 subgroups did not change from preoperative up to the last available follow-up (all P > 0.05), whereas best spectacle-corrected visual acuity improved for group 1 ( P = 0.03). Group 1 showed an average Kmax reduction of 7D in the first month ( P < 0.001) with no further changes up to 8 years postoperatively ( P > 0.05), whereas no significant changes were observed in group 2 (all P > 0.05). Postoperative KC progression occurred in 4 eyes (n = 3 group 1, n = 1 group 2) and 1 eye (group 2) underwent retransplantation for unsatisfactory visual performance. Kaplan-Meier analysis showed an estimated success rate of 85% at the 5 to 8 years follow-up in group 1 and of 75% at the 5 to 7 years follow-up for group 2. CONCLUSIONS: BL inlay transplantation stabilized KC in most eyes along with preservation of contact lens tolerance up to 8 years postoperatively and may be a successful treatment option, in particular for eyes with progressive advanced KC (Kmax > 69D).

First Clinical Experience With Ophthalmic e-Device for Unaided Patient Self-Examination During COVID-19 Lockdown.

PURPOSE: The aim of this study was to describe a new type of medical device that allows for internet-enabled patient self-screening, without the aid of an ophthalmic professional, through biomicroscopy self-imaging and self-measurement of the best-corrected visual acuity (BCVA). METHODS: In this prospective nonrandomized comparative study, 56 patients were instructed to screen their own eyes using a custom-built e-Device containing miniaturized slitlamp optics and a visual acuity Snellen chart virtually projected at 20 ft. BCVA measurements were recorded, and biomicroscopic videos were scored for image quality of the anterior segment status on a scale from 1 to 5 (1 = poor and 5 = excellent) by a blinded observer. RESULTS: After a short instruction, all patients were able to self-image their eyes and perform a self-BCVA measurement using the e-Device. Patient self-image quality with the e-Device scored on average 3.3 (±0.8) for videos (n = 76) and 3.6 (±0.6) for photographs (n = 49). Self-BCVA measurement was within 1 Snellen line from routine BCVA levels in 66 of 72 eyes (92%). When compared with conventional biomicroscopy, patient self-biomicroscopy allowed for recognition of the relevant pathology (or absence thereof) in 26 of 35 eyes (74%); 9 cases showed insufficient image quality attributed to device operating error (n = 6) and mild corneal edema and/or scarring (n = 3). Patient satisfaction with the device was 4.4 (±0.9). CONCLUSIONS: An e-Device for combined BCVA self-measurement and biomicroscopy self-imaging may have potential as an aid in remote ophthalmic examination in the absence of an ophthalmic professional and may be considered for patients who are unable to visit an ophthalmic clinic for routine follow-up.

Acute Hydrops After Bowman Layer Transplantation for Keratoconus May Indicate that Descemet Membrane Rupture Is Secondary to Hydrops.

PURPOSE: The aim of this study was to review the postoperative course and imaging features of 7 eyes that presented with corneal hydrops after Bowman layer (BL) transplantation was performed for advanced keratoconus to determine the potential mechanisms of hydrops formation. METHODS: A retrospective analysis was performed of 7 eyes of 5 patients with advanced keratoconus that underwent midstromal BL transplantation at 2 tertiary referral centers and developed acute corneal hydrops on average 64 (±30) months (range 14-104 months) postoperatively. Corneal tomography and anterior segment optical coherence tomography (AS-OCT) images were reviewed to document the postoperative and posthydrops course. RESULTS: For all eyes, the post-BL transplantation course was uneventful until hydrops development. Despite stable postoperative topographies in 5 of 7 eyes, eyes developed hydrops with typical hypodense areas on AS-OCT that were limited to the stromal layers posterior to the BL graft. With AS-OCT (6/7 eyes), 2 eyes showed a break in Descemet membrane, whereas Descemet membrane was intact across the cornea in 2 eyes; in 2 eyes, the images were inconclusive. All patients admitted to continued eye rubbing, and all but 1 had a clinically significant allergy and/or atopic constitution. Most eyes (5/7) showed a relatively quick (visual) recovery within 1 to 4 months after hydrops. CONCLUSIONS: Hydrops formation in keratoconic corneas after midstromal BL transplantation may indicate that a break in Descemet membrane is secondary to hydrops development (and not vice versa). With a midstromal BL graft in situ limiting hydrops dimensions, resolution of the hydrops seemed relatively quick with recovery to prehydrops visual acuity in most eyes.

Effect of Six-Month Postoperative Endothelial Cell Density on Graft Survival after Descemet Membrane Endothelial Keratoplasty.

PURPOSE: To analyze if 6-month endothelial cell density (ECD) affects long-term ECD outcome and graft survival 5 years after Descemet membrane endothelial keratoplasty (DMEK) in eyes with Fuchs endothelial corneal dystrophy (FECD). DESIGN: Retrospective cohort study. PARTICIPANTS: A total of 585 DMEK eyes were included. The study group was divided into 4 groups based on 6-month ECD quartiles: group 1 (n = 146) with 313 to 1245 cells/mm2, group 2 (n = 148) with 1246 to 1610 cells/mm2, group 3 (n = 145) with 1611 to 1938 cells/mm2, and group 4 (n = 146) with 1939 to 2760 cells/mm2. Group 1 was further split into subgroups 1a (n = 36) with 6-month ECD of ≤828 cells/mm2, 1b (n = 37) with 829 to 1023 cells/mm2, 1c (n = 37) with 1024 to 1140 cells/mm2, and 1d (n = 36) 1141 to 1245 cells/mm2. METHODS: Descemet membrane endothelial keratoplasty. MAIN OUTCOME MEASURES: Long-term ECD, graft survival, and postoperative complication rates. RESULTS: For group 1, 6-month ECD decreased from 951 (±233) cells/mm2 (n = 146) to 735 (±216) cells/mm2 (n = 99) at 5 years postoperatively. Group 1 graft survival probability was 0.95 (95% confidence interval [CI], 0.91-0.99] at 5 years postoperatively, which was lower than for groups 2 to 4 (P = 0.001). Five-year graft survival in subgroup 1a was 0.79 (95% CI, 0.67-0.94), which was lower than in subgroups 1b to 1d (P = 0.001). Preoperative ECD did not influence graft survival (P = 0.400), and higher 6-month ECD values were associated with lower graft failure rates (hazard ratio, 0.994; 95% CI, 0.99-1.00; P = 0.001). CONCLUSIONS: Six-month ECD is associated with DMEK graft survival. High early cell loss after DMEK negatively affects long-term ECD outcome and graft survival. Grafts in the lowest 6-month ECD subgroup (≤828 cells/mm2) are at higher risk of failure within 5 years after DMEK. To ensure sufficiently high 6-month ECD, preoperative graft quality assessment should be optimized, and cellular stress induced to the graft should be minimized. Additionally, developing therapeutic options for the treatment of low postoperative ECD could further improve DMEK graft longevity.

Bowman Layer Onlay Grafting: Proof-of-Concept of a New Technique to Flatten Corneal Curvature and Reduce Progression in Keratoconus.

PURPOSE: The aim of this study was to describe a new surgical technique for flattening the corneal curvature and to reduce progression in eyes with advanced progressive keratoconus (KC) by using Bowman layer (BL) onlay grafting and to report on the preliminary outcomes of this procedure. METHODS: In this prospective interventional case series, 5 patients with advanced progressive KC underwent BL onlay grafting. After removal of the epithelium, a BL graft was placed and "stretched" onto the stroma, and a bandage lens was placed to cover the BL graft. In 1 case, BL onlay grafting could be performed immediately after ultraviolet corneal crosslinking; all other eyes were ineligible for ultraviolet corneal crosslinking. Best spectacle- and/or best contact lens-corrected visual acuity, refraction, biomicroscopy, corneal tomography, anterior segment optical coherence tomography, and complications were recorded at 1 week and at 1, 3, 6, 9, and 12 to 15 months postoperatively. RESULTS: All 5 surgeries could be performed successfully. Average maximum keratometry went from 75 diopters (D) preoperatively to 70 D at 1 year postoperatively. All eyes showed a completely reepithelialized and a well-integrated graft. Best spectacle-corrected visual acuity improved at least 2 Snellen lines (or more) in 3 of 5 cases and best contact lens-corrected visual acuity remained stable, improving by 3 Snellen lines in case 1 at 15 months postoperatively. Satisfaction was high, and all eyes again had full contact lens tolerance. CONCLUSIONS: BL onlay grafting may be a feasible surgical technique, providing up to -5 D of corneal flattening in eyes with advanced KC.

Descemet Membrane Endothelial Keratoplasty and Bowman Layer Transplantation: An Anatomic Review and Historical Survey.

For nearly a century, the definitive treatment of many corneal dystrophies and ectactic disorders was limited to penetrating keratoplasty, but over the past 2 decades, a surge of surgical innovation has propelled the treatment of many corneal diseases to more targeted approaches with significantly better visual outcomes. Anterior stromal diseases were first changed through endothelial-sparing techniques, such as deep anterior lamellar keratoplasty, but have more recently transitioned to stromal-sparing approaches. Ultraviolet corneal crosslinking strengthens the cornea and halts progression of keratoconus in >90% of cases. Intracorneal ring segment and corneal allogenic ring segment implantation offer methods to flatten ectatic corneas. However, Bowman layer transplantation - inlay and more recently onlay techniques - has shown promise for treating advanced keratoconus and preventing keratoplasty. The advent of endothelial keratoplasty radically changed the treatment of corneal endothelial dysfunction, and Descemet membrane endothelial keratoplasty specifically offers an average postoperative visual acuity of 20/25 (0.8) with only 8.8% of grafts requiring retransplantation in the first 5 years. Here, we review the rapid innovations for surgical treatment of corneal diseases, spanning from endothelial keratoplasty and endothelial regeneration to anterior lamellar keratoplasty and stromal augmentation, highlighting key steps which may be moving us closer to a "postkeratoplasty" world.

Phacoemulsification After Descemet Membrane Endothelial Keratoplasty: Incidence and Influence on Endothelial Cell Density.

PURPOSE: To analyze the incidence of cataract extraction after Descemet membrane endothelial keratoplasty (DMEK) in phakic eyes and to evaluate the effect of phacoemulsification after DMEK on the donor endothelial cell density (ECD). METHODS: The clinical data of phakic patients with DMEK were examined. From this cohort, all patients who subsequently underwent phacoemulsification after DMEK were reviewed. Data from a prospectively collected dataset were analyzed, including demographic profile, ECD, corrected distance visual acuity (CDVA), central corneal thickness (CCT), and complications. RESULTS: From a series of 261 phakic patients with DMEK, 35 eyes (13.4%) required cataract surgery within the mean follow-up period of 54.2 ± 28 months. The mean time from DMEK to phacoemulsification was 18 ± 13 months (range: 3 to 69 months). The probability of cataract extraction after DMEK was 0.06 (95% CI: 0.03 to 0.09) at 1 year and 0.17 (95% CI: 0.12 to 0.22) at 10 years, respectively. ECD decreased from 1,314 ± 524 cells/mm2 before phacoemulsification to 1,167 ± 443 cells/mm2 (-11%) at 1 to 6 months postoperatively (P = .333). CDVA improved from 0.27 ± 0.13 logMAR preoperatively to 0.07 ± 0.12 logMAR at 1 to 6 months postoperatively. CCT before phacoemulsification was 532 ± 46 µm and remained stable at 539 ± 56 µm at 1 to 6 months after phacoemulsification. Phacoemulsification did not elicit DMEK graft detachment in any of the eyes studied. CONCLUSIONS: The incidence and 10-year projection of cataract extraction in phakic eyes with DMEK was relatively low. Phacoemulsification after DMEK provided excellent CDVA outcomes, did not induce graft detachment, and was associated with an acceptable decrease in ECD. [J Refract Surg. 2021;37(2):119-125.].

Intrastromal Descemet Membrane Transplantation as a Potential Alternative to Bowman Layer Inlays in Eyes With Advanced Keratoconus.

ABSTRACT: Herein, we report the outcomes of intrastromal Descemet membrane (DM) transplantation in corneas with advanced keratoconus. Three eyes (three patients) showed advanced keratoconus. No eye underwent prior UV-cross-linking or any other ocular surgery. In all eyes, A donor DM was implanted into a mid-stromal pocket and clinical outcomes were evaluated up to 24 months after surgery. All procedures were uneventful. Up to 24 months postoperatively, the DM graft was well-positioned and barely visible within the recipient stroma; all corneas were clear. No eye showed signs of keratoconus progression throughout the follow-up. No changes were observed in uncorrected and best contact lens corrected visual acuity, central endothelial cell density, corneal thinnest point pachymetry, and maximum keratometry values. No early or late postoperative complications were observed. Intrastromal DM transplantation may be an alternative to intrastromal Bowman layer transplantation in advanced keratoconus, to postpone deep anterior lamellar or penetrating keratoplasty.

Bowman Layer Onlay Graft for Reducing Fluctuation in Visual Acuity After Previous Radial Keratotomy.

PURPOSE: To describe the clinical outcome of a first patient undergoing Bowman layer (BL) transplantation with an onlay graft to reduce fluctuation in visual acuity and refractive error after previous radial keratotomy (RK) surgery. METHODS: In 2018, a 66-year-old woman presented with complaints of long-standing diurnal fluctuation in best-spectacle corrected visual acuity (BSCVA) after RK in 1983. After the removal of host epithelium, a BL graft was positioned onto the host cornea. BSCVA, Scheimpflug-based corneal tomography, and anterior segment optical coherence tomography were evaluated up to 12 months postoperatively. RESULTS: The surgery and postoperative course were uneventful. After surgery, the subjective complaints of visual fluctuation were reduced from 10 to 3 on a scale from 1 to 10. BSCVA (20/40; 0.5) did not change from preoperative to postoperative. Corneal tomography showed an overall central corneal steepening of 5.9 diopters. Biomicroscopy, Scheimpflug imaging, and anterior segment optical coherence tomography showed a completely epithelialized and well-integrated graft, with some minor epithelial remnants located in the preexisting keratotomy incisions. CONCLUSIONS: BL onlay grafting may have the potential to manage patients with subjective complaints of diurnal fluctuation in visual acuity after previous RK.

Descemet Membrane Endothelial Keratoplasty: Ten-Year Graft Survival and Clinical Outcomes.

PURPOSE: To evaluate the 10-year graft survival and clinical outcomes of the first case series after Descemet membrane endothelial keratoplasty (DMEK). DESIGN: Retrospective, interventional case series. METHODS: After excluding the very first 25 DMEK eyes that constitute the technique learning curve, the following 100 consecutive primary DMEK eyes (88 patients) were included. Main outcome parameters (survival, best-corrected visual acuity [BCVA], central endothelial cell density [ECD], and central corneal thickness [CCT]) were evaluated up to 10 years postoperatively, and postoperative complications were documented. RESULTS: At 5 and 10 years after DMEK, 68 and 57 of 100 eyes, respectively, were still available for analysis. Of those eyes, 82% and 89% reached a BCVA of ≥20/25 (decimal VA ≥0.8) at 5- and 10 years postoperatively, respectively. Preoperative donor ECD decreased by 59% at 5 years and 68% at 10 years postoperatively. CCT averaged 668 ±74 µm preoperatively and 540 ± 33 µm and 553 ± 43 µm at 5 and 10 years, respectively, after surgery. Within 10 years, 4% of eyes developed allograft rejection, no primary graft failures occurred, and 6% of the eyes developed secondary graft failure. Graft survival probability was 0.83 (95% confidence interval [CI], 0.75-0.92) and 0.79 (95% CI, 0.70-0.88) at 5 and 10 years postoperatively, respectively. CONCLUSIONS: Most eyes that underwent surgery in the pioneering phase of DMEK showed excellent and stable clinical outcomes with low postoperative complication rates and promising graft longevity over the first decade after surgery. This suggests that DMEK may be a safe long-term treatment option for corneal endothelial diseases.

Endothelial Cell Density Changes in the Corneal Center Versus Paracentral Areas After Descemet Membrane Endothelial Keratoplasty.

PURPOSE: To analyze whether endothelial cell density (ECD) differs between central and paracentral areas after Descemet membrane endothelial keratoplasty (DMEK) and to identify the locations of the highest and lowest ECD. METHODS: In this retrospective cohort study, central and paracentral ECDs of 30 eyes of 30 patients who underwent DMEK for Fuchs endothelial corneal dystrophy were evaluated. Central, superonasal, superotemporal, and inferior specular microscopic images were analyzed at 1, 3, 6, 9, and 12 months after DMEK. Changes in ECD by location and over time and changes in location for the highest and lowest ECD were evaluated. RESULTS: When compared with the preoperative donor ECD, the central ECD decreased by 32 (±11)% at 12 months postoperatively. ECD decline between 1 and 12 months postoperatively in the central, inferior, superonasal, and superotemporal location were 7%, 12%, 16%, and 13%, respectively (P < 0.0001 for all locations). Mean ECD was the highest in the center between the 3- to 12-month follow-up, whereas mean ECD was the lowest in the paracentral superonasal area at all time points (P < 0.001). Mean ECD of the highest and lowest density locations differed at all follow-up time points (P < 0.003). CONCLUSIONS: Postoperative ECD was not found to be uniform across the graft. Contrary to the density distribution in the normal endothelium, paracentral area ECDs were found to be consistently lower than in the central area. These differences were most prominent in the superonasal area and persisted 12 months postoperatively. Central ECD after DMEK might, thus, not represent an accurate proxy for cell density of the entire graft.

Bowman Layer Onlay Transplantation to Manage Herpes Corneal Scar.

PURPOSE: To introduce the concept of using a Bowman layer (BL) onlay graft to manage superficial herpetic corneal scarring and to describe the clinical outcomes of the first 2 cases undergoing this procedure. METHODS: Two patients with a quiescent superficial corneal scar after herpes (varicella zoster virus [n = 1] and herpes simplex virus [n = 1]) keratitis underwent BL onlay transplantation. After the removal of the host epithelium and limited superficial keratectomy, an isolated BL graft was placed onto the host corneal surface. The cornea was then covered with an amniotic membrane and a bandage contact lens. Best spectacle-corrected visual acuity (VA) and/or best contact lens-corrected VA (BCLVA), biomicroscopy, corneal tomography, and anterior segment optical coherence tomography were recorded at 1 week, 1 month, and 3, 6, 9, 12, and 18 months postoperatively. RESULTS: In both cases, the surgical and postoperative courses were uneventful. An improvement of the corneal clarity was observed at biomicroscopy, and no varicella zoster virus/herpes simplex virus reactivation occurred throughout the follow-up period. Biomicroscopy, Scheimpflug imaging, and anterior segment optical coherence tomography showed a completely epithelialized and well-integrated graft postoperatively. In case 1, BCLVA with a scleral lens improved from 20/100 (0.1) preoperatively to 20/32 (0.6) postoperatively. For case 2, no preoperative BCLVA was available, but a BCLVA of 20/36 (0.55) was achieved after the procedure. CONCLUSIONS: A BL onlay graft may be a feasible surgical procedure, which may have the potential to reduce superficial corneal scarring and/or anterior corneal irregularities without resorting to deeper keratoplasty in these complex cases.

Parameters Associated With Endothelial Cell Density Variability After Descemet Membrane Endothelial Keratoplasty.

PURPOSE: To evaluate which parameters may affect endothelial cell loss after Descemet membrane endothelial keratoplasty (DMEK) by comparing eyes in the low vs high quartile of endothelial cell loss over a follow-up period of 4 years. DESIGN: Retrospective cohort study. METHODS: Donor endothelial cell density (ECD) decline was evaluated for 351 eyes of 275 patients up to 4 years after DMEK for Fuchs endothelial corneal dystrophy (FECD). Eyes with a postoperative endothelial cell loss in the lower quartile at all available follow-up moments were assigned to Group 1 (n = 51) and those in the upper quartile to Group 2 (n = 42). Multinomial regression was used to assess which covariates were related to greater ECD decline. RESULTS: Mean endothelial cell loss as compared to preoperative donor ECD for the entire study group was 33 (±16)%, 36 (±17)%, and 52 (±18)% at 1, 6, and 48 months postoperatively. Endothelial cell loss of Group 1 was 12 (±7)%, 13 (±6)%, and 26 (±8)% at, respectively, 1, 6, and 48 months postoperatively, and 59 (±10)%, 64 (±9)%, and 75 (±5)% in Group 2. Partial graft detachment, donor death cause cardiovascular/stroke (vs cancer), postoperative complications other than graft detachment, and severity of preoperative FECD (all P < .01) showed the strongest relation with greater ECD decline. CONCLUSIONS: DMEK eyes with a completely attached graft and operated in an early stage of FECD may show the lowest endothelial cell loss postoperatively.

Effect of Surgical Indication and Preoperative Lens Status on Descemet Membrane Endothelial Keratoplasty Outcomes.

PURPOSE: To analyze 6-month results of 1000 consecutive Descemet membrane endothelial keratoplasty (DMEK) cases, and to evaluate if outcomes are influenced by surgical indication and preoperative lens status. DESIGN: Retrospective, interventional case series. METHODS: A series of 1000 eyes (738 patients) underwent DMEK mainly for Fuchs endothelial corneal dystrophy (FECD; 85.3%) or bullous keratopathy (BK; 10.5%). Main outcome measures were best-corrected visual acuity (BCVA), endothelial cell density, postoperative complications, and retransplantations. RESULTS: At 6 months after DMEK, there was no difference in BCVA outcome between FECD and BK eyes (P = .170), or between phakic and pseudophakic FECD eyes (P = .066) after correcting for patient age and preoperative BCVA. Endothelial cell loss at 6 months postoperatively was similar for phakic and pseudophakic FECD eyes (39%; P = .852), but higher for BK eyes than for FECD eyes (46% vs 39%, P = .001). Primary and secondary graft failure occurred in 3 (0.3%) and 2 eyes (0.2%), respectively, and 7 eyes developed allograft rejection (0.7%). Eighty-two eyes (8.2%) received rebubbling for graft detachment and retransplantation was performed in 20 eyes (2.0%). Rebubbling was more often required in eyes treated for BK vs FECD eyes (12.4% vs 7.4%, P = .022). CONCLUSION: DMEK consistently provides excellent short-term results, with similar high visual acuity levels for both FECD and BK eyes. As preoperative lens status did not influence DMEK outcomes, for phakic FECD eyes with a still relatively clear crystalline lens, lens preservation may be preferable in a selected group of younger patients, who may still benefit from their residual accommodative capacity.