Fuchs endothelial corneal dystrophy (FECD) is caused by a corneal endothelial cell loss, leading to corneal edema and visual impairment. The most significant genetic risk factor for FECD is an expansion of the CTG18.1 locus in transcription factor 4 (TCF4). The current treatment for severe FECD is corneal transplantation, with Descemet stripping automated keratoplasty (DSAEK) as a common surgical method. Although successful in most cases, the risk for transplant failure due to diverse causes must be considered. In this study, we investigated if presence of TCF4 CTG18.1 expansion with more than 31 (n ≥ 31) repeats in donated corneal grafts could be a reason for corneal transplant failure after DSAEK. For this, nine consecutively failed DSAEK corneal grafts were genotyped for CTG18.1 repeat length. One-sided Mann-Whitney U test was performed to evaluate if failed DSAEK corneal grafts had longer CTG18.1 repeats than healthy controls from the same population. All failed corneal grafts had CTG18.1 n ≤ 27 with a median of 18 (IQR 8.0) repeats for the longest allele. There was no statistical difference in CTG18.1 repeat lengths between failed corneal grafts and the geographically matched healthy control group. In conclusion, none of the nine failed corneal grafts in our material had CTG18.1 repeat lengths ≥ 31, a cut-off known to have a biological relevance in FECD. Thus, our results suggest that the assessment of donors and inspection of the corneal tissue before the decision for procurement is sufficient, in terms of recognizing FECD in the donor.

The two most used modifications of endothelial keratoplasty (EK) are Descemet\'s membrane endothelial keratoplasty (DMEK) and Descemet\'s stripping automated endothelial keratoplasty (DSAEK). The leading complication of EK surgeries is graft detachment in the early postoperative period. This article reports on two cases of endothelial graft adhesion depending on morphological characteristics of the Descemet\'s membrane (DM) removed during EK. In the first case, complete graft attachment to the recipient\'s posterior stroma was observed after DMEK. Morphological analysis of the DM showed clean stromal surface. In the second case there was a false chamber between the endothelial transplant and the posterior stroma of the patient. OCT scans revealed separate stromal fibers protruding into the false chamber; morphological analysis of the removed DM showed stromal fragments fixed to the anterior surface of the DM. The revealed changes indicate damage to the posterior stroma the suffered received during descemetorhexis, which may be the cause for incomplete graft attachment. Complete attachment after repeated EK (DSAEK) in this case was due to a thin stromal layer on the graft that provided high degree of adhesion to the posterior corneal surface. DSAEK can be indicated as a repeated EK surgery in cases of persistent endothelial graft non-attachment after DMEK.
Основными модификациями эндотелиальной кератопластики (ЭК) считают изолированную трансплантацию десцеметовой мембраны (ДМ) с эндотелием (Descemet membrane endothelial keratoplasty, DMEK) и автоматизированную ЭК (Descemet stripping automated endothelial keratoplasty, DSAEK). Ведущим послеоперационным осложнением ЭК является возникновение ложной камеры между трансплантатом и роговицей реципиента. В статье представлены два клинических наблюдения адаптации эндотелиального трансплантата в зависимости от морфологических особенностей ДМ, удаленной при ЭК. В первом случае после DMEK отмечается полное прилегание трансплантата к строме реципиента по данным оптической когерентной томографии (ОКТ). При морфологическом исследовании визуализируется гладкая стромальная поверхность удаленной ДМ. Во втором наблюдении выявлена ложная камера между эндотелиальным трансплантатом и задней стромой реципиента. При ОКТ обнаружены отдельные стромальные волокна, проминирующие в ложную камеру; при морфологическом анализе удаленной ДМ реципиента отмечены фрагменты стромы, фиксированные к передней поверхности ДМ. Выявленные изменения свидетельствуют о повреждении задней стромы реципиента при десцеметорексисе, что может быть причиной неполного прилегания эндотелиального трансплантата. Полная адаптация трансплантата при повторной ЭК (DSAEK) в этом клиническом наблюдении, вероятно, обусловлена тем, что тонкий слой стромы в составе трансплантата обеспечивает высокую степень его адгезии к задней поверхности роговицы реципиента. Проведение DSAEK показано в качестве рекератопластики при стойком неприлегании эндотелиального трансплантата после DMEK.

OBJECTIVE: To evaluate and compare the biomechanical properties of the eye bank-prepared and surgeon prepared Descemet stripping automated endothelial keratoplasty (DSAEK) tissues.
METHODS: In this laboratory study, corneal tissues for research were randomly allocated in the following groups: a) surgeon-cut DSAEK and b) eye bank-prepared (pre-cut and pre-loaded) DSAEK. Endothelial cell loss (ECL), immunostaining for tight junction protein ZO-1, elastic modulus, and adhesion force were investigated.
RESULTS: ECL was not found to be significantly different between surgeon-cut DSAEK (7.8% ±6.5%), pre-cut DSAEK (8.6% ±2.3%), and pre-loaded DSAEK (11.1% ±4.8%) (P = 0.5910). ZO-1 was expressed equally across all groups. Surgeon-cut DSAEK grafts showed a significantly higher elastic modulus compared to pre-cut and pre-loaded DSAEK groups (P = 0.0047 and P < 0.0001, respectively). Adhesion force was significantly greater in the surgeon-cut DSAEK compared to pre-cut (P < 0.0001) or pre-loaded DSAEK groups (P = 0.0101).
CONCLUSIONS: The laboratory data on the biomechanics of DSAEK grafts suggests that surgeon-cut DSAEK grafts present higher elastic modulus and adhesion force compared to eye bank-prepared DSAEK grafts.

OBJECTIVE: To identify the causes of failure of the different surgical corneal graft techniques: penetrating keratoplasty (PK), deep anterior lamellar keratoplasty (DALK), Descemet stripping automated endothelial keratoplasty (DSAEK) and Descemet membrane endothelial keratoplasty (DMEK).
METHODS: This multicentric retrospective study enrolled a consecutive cohort of patients who had undergone any type of keratoplasty between 2001 and 2016. The clinical data were obtained from the patient\'s medical records, following ethical guidelines, permissions and data protection. The main outcome measured in the study was the cause of graft failure, defined as any irreversible loss of graft transparency capable of compromising vision. The main causes of graft failure were classified as follows: (A) primary graft failure (PGF), (B) immunological rejection, (C) non-rejection (which includes endothelial decompensation without rejection, IOP elevation/glaucoma, diseases of the ocular surface, recurrence of the primary disease, wound dehiscence/hypotonia and trauma, among others) and (D) specific causes of lamellar keratoplasty failure. A descriptive study of the obtained data was carried out. The distribution of the causes of failure was evaluated according to the type of corneal transplant.
RESULTS: Our research included a cohort of 571 keratoplasty failures, of which 509 met the inclusion criteria. The analysis of the causes of the PK failure showed that immunological allograft rejection represented the main cause, with 28.2% of the failures, followed by surface diseases (17.8%) and endothelial decompensation without rejection (17.3%). For the PK re-grafts group, the main cause of failure was immunological allograft rejection (34.0%), followed by diseases of the ocular surface (18.5%). For the DALK group, the failures mainly occurred due to surface diseases such as limbal stem cell insufficiency, infectious keratitis, keratolysis or persistent epithelial defect (37.8%). However, the main reason for failure in the DSAEK group was endothelial decompensation without rejection (31.9%) while primary graft failure was the main cause of failure in the DMEK group (64.1%).
CONCLUSIONS: The main reason for failure in PK was immunological allograft rejection, both in primary and secondary transplants. The leading causes for failure were diseases of the ocular surface in the DALK population, endothelial decompensation without rejection in DSAEK and primary graft failure in DMEK.

OBJECTIVE: Corneal thickness inevitably increases following Descemet\'s stripping automated endothelial keratoplasty (DSAEK), owing to the addition of a donor graft. The current study compares different devices in assessing post-DSAEK intraocular pressure (IOP).
METHODS: We compared IOP values measured by the Goldmann tonometry (GAT), iCare rebound tonometry (iCare) and Pascal dynamic contour tonometry (PDCT) in eyes following DSAEK. Agreement between measurements was calculated with correlation analysis and Bland-Altman plots. Effects of keratometry, central, thickness (CCT), endothelial cell density (ECD) and axial length on IOP measurements were assessed with Pearson\'s correlation.
RESULTS: Twenty eyes of 20 patients (mean age 74.3±14.4, 14 females) post-DSAEK were included in this study. There was a high concordance between the IOP readings obtained by the three devices: a strong and significant correlation was found between GAT and PDCT (r=0.94, P<0.001) GAT and iCare (r=0.86, P<0.001) and iCare with PDCT (r=0.81, P<0.001). However, the iCare measurements were significantly and consistently lower than that obtained with GAT (ΔIOP=1.68±2.0, P=0.002, 95% CI: 0.7-2.6) and with PDCT (ΔIOP=1.61±2.5, P=0.01, 95% CI: 0.4-2.8). CCT, ECD, CCT, AXL, corneal curvature or astigmatism did not influence IOP measurement by any instrument.
CONCLUSIONS: IOP measurement with three different techniques (applanation, rebound and dynamic contour) showed good correlations, despite an increased corneal thickness following DSAEK. However, the iCare, which is based on a rebound tonometry showed significant lower IOP then the two other methods. This should be taken into account when evaluating patients post DSAEK.

OBJECTIVE: According to some pioneer surgeons, lamellar endothelial keratoplasty techniques (EK), including Descemet membrane endothelial keratoplasty (DMEK) and Descemet stripping automated endothelial keratoplasty (DSAEK), yield excellent clinical results. However, there is a lack of studies with high levels of evidence and results of large national keratoplasty registers are contradictory. Therefore, two large cohorts of DMEK and DSAEK procedures are compared to a cohort of penetrating keratoplasty (PK).
METHODS: The study reports 868 keratoplasty procedures at a single centre (694 eyes with Fuchs endothelial dystrophy (FED) and 174 with bullous keratopathy (BK)). Patients underwent DMEK (450 eyes), DSAEK (89 eyes), or PK (329 eyes). Postoperative visual acuity, endothelial cell density (ECD), rate of regrafting, and rejections were recorded.
RESULTS: Visual acuity recovers faster and to a greater extent in EK compared to PK. DMEK performs better than DSAEK. ECD drops faster initially for EK compared to PK. In EK the rate of regrafting is higher than in PK (7 % in DMEK, 20 % in DSAEK and 2 % in PK in FED). The rejection rate is lowest following DMEK (7 % after DMEK, 21 % after DSAEK and 18 % after PK in FED).
CONCLUSIONS: In contrast to recent reports from national keratoplasty registers, the overall clinical outcome of EK in FED and BK is superior to PK. Including ocular comorbidities and learning curves, these data reflect a realistic setting for comparing the different keratoplasty techniques. Corneal surgeons may be encouraged to preferentially use DMEK in FED and BK.

OBJECTIVE: To compare postoperative complications after Descemet stripping with automated endothelial keratoplasty (DSAEK) in patients with and without glaucoma.
METHODS: For this retrospective study a series of 298 DSAEK cases performed at the Doheny Eye Institute were taken, we compared postoperative complications in eyes with glaucoma on medication (55) or with previous glaucoma surgeries (64) with a time-matched group of all other DSAEK cases (179, control).
RESULTS: With a mean follow-up of 1.85 ± 1.12 years, the complication rates were 12.8%, 11.1%, and 26.8% for postoperative graft detachment, graft failure, and IOP elevation, respectively. Graft detachment was an independent risk factor for graft failure (odds ratio OR = 12.35, 95% confidence interval CI [5.46-27.90], P < 0.001). Graft detachment was not associated with either history of glaucoma or glaucoma surgery (P > 0.05). Glaucoma on medication had no increased risks of graft failure compared to normal eyes (P = 0.38). However, increased risk of failure was seen in eyes with prior incisional glaucoma surgeries (OR = 4.26, 95% CI [1.87-9.71], P < 0.001). Medically managed glaucoma has increased risks of postoperative IOP elevation (OR = 2.39, 95% CI [1.25-4.57], P = 0.013), whereas surgically managed glaucoma has no significant elevation (P = 0.23). Elevation of IOP was not significantly correlated with graft failure (P = 0.21).
CONCLUSIONS: DSAEK is the preferred treatment for corneal endothelial dystrophy. We observed that having glaucoma or glaucoma surgery is not associated with graft detachment. A history of glaucoma surgery and postoperative graft detachment appeared to be important risk factors for graft failure. And more studies are indicated to study long-term IOP evolution in post-DSAEK patients and its association with graft survival.