Giant corneal keloid following Descemet stripping automated endothelial keratoplasty for the treatment of corneal decompensation secondary to trauma.

PURPOSE: This report aims to present a case of corneal keloid caused by chronic corneal insult after trauma and Descemet stripping automated endothelial keratoplasty (DSAEK). CASE PRESENTATION: A 35-year-old male with a history of vision loss in the right eye was referred to our hospital. The patient underwent Ahmed Glaucoma Valve Implantation to alleviate elevated intraocular pressure after ocular trauma to the same eye. One year following the procedure, the eye developed endothelial failure, leading to the performance of Descemet's Stripping Automated Endothelial Keratoplasty (DSAEK) with repositioning of the shunt tube. Upon initial examination, a well-circumscribed elevated white opaque lesion involving the central corneal surface of the RE was observed. Based on the patient's clinical history, slit lamp examination, and UBM findings, the diagnosis of corneal keloid was established. Superficial keratectomy was performed. Histopathological analysis confirmed the diagnosis of corneal keloid. Following the procedure, BCVA improved slightly. However, 3 months later, the patient underwent a penetrating keratoplasty for visual rehabilitation. CONCLUSION: Corneal keloids should be considered following any form of ocular trauma, particularly in cases involving ocular surgery. Diagnosing corneal keloids can sometimes be challenging due to the variety of potential differentials; however, by carefully evaluating the patient's medical history and clinical presentation, we can effectively narrow down the differential diagnosis of corneal conditions.

CTG18.1 expansion in transcription factor 4 (TCF4) in corneal graft failure: preliminary study.

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.

Graft dislocation following Descemet stripping automated endothelial keratoplasty: a comparative cohort analysis of Optisol GS and organ culture preserved corneas.

Previous studies have suggested risk factors for graft dislocation after Descemet stripping automated endothelial keratoplasty (DSAEK). We aimed to investigate the influence of eye bank storage solution as a risk factor for graft dislocation, as this could have significant implications for eye banking practices. This retrospective analysis compared cohorts from the QEII Health Sciences Center, Halifax, Canada (donor corneas preserved in Optisol GS) and the Royal Victorian Eye and Ear Hospital, Melbourne, Australia (donor corneas preserved in organ culture). Patient, surgical, and post-operative data were collected for consecutive DSAEK surgeries performed between 2012 and 2020. Risk factors were analyzed using univariate and multivariate logistic regression modeling. 654 DSAEK surgeries were performed during the study period: 271 in the Optisol GS storage cohort and 383 in the organ culture cohort. The most common indications were pseudophakic bullous keratopathy, Fuchs endothelial dystrophy, and failed previous DSAEK. The incidence of graft dislocation requiring surgical repositioning was 9.6% (n = 26) in the Optisol GS cohort and 12.0% (n = 46) in the organ culture cohort (OR, 0.50, 95% CI, 0.20-1.13). Development of graft dislocation was associated with intraoperative venting incisions (OR, 2.50, 95% CI, 1.12-5.51) and a post-operative wound leak (OR, 55.24, 95% CI, 10.20-514.85). The incidence of DSAEK dislocation was similar between study sites using Optisol GS and organ culture, suggesting changes in eye bank storage solution would not mitigate this post-operative complication. Intraoperative creation of venting incisions and post-operative wound leaks and were factors associated with graft dislocation.

Disparities in Visual Acuity Outcomes after Endothelial Keratoplasty: An Intelligent Research in Sight Registry Analysis.

PURPOSE: To assess risk factors for lack of vision improvement after endothelial keratoplasty (EK). DESIGN: Retrospective cohort study. PARTICIPANTS: Patients aged 18 years and older in the Intelligent Research in Sight (IRIS®) Registry who underwent EK surgery in the United States between 2013 and 2018. METHODS: Change in visual acuity (VA) relative to baseline were determined at 6 months and 1 year. A multivariable population-average marginal model estimated using generalized estimating equations adjusting for sociodemographic factors, baseline vision, surgical indication, ocular comorbidities, and postoperative complications was used to identify factors associated with worse VA outcomes. MAIN OUTCOME MEASURES: Visual acuity and lack of VA improvement at 1 year compared with preoperative status. RESULTS: A total of 30 600 EK procedures (N = 25 666 unique patients) were included in the analysis. Overall, VA improved from median logarithm of the minimum angle of resolution (logMAR) 0.54 (Snellen 20/69) (interquartile range [IQR] ± 0.70) preoperatively to median logMAR 0.40 (20/50) (IQR ± 0.36) at 6 months and median logMAR 0.30 (20/40) (IQR ± 0.36) at 1 year postoperatively. A total of 30.3% of the overall cohort, 29.8% of Fuchs' endothelial corneal dystrophy (FECD) subgroup, and 27.4% of the bullous keratopathy (BK) subgroup did not show visual improvement at 1 year postoperatively. In the FECD subgroup, older age (risk ratio [RR], 1.05 per 5-year increase, 95% confidence interval [CI], 1.03-1.07) and female sex (RR, 1.10, 95% CI, 1.04-1.16) were associated with VA worse than or equal to baseline at 1 year postoperatively. In both FECD and BK subgroups, eyes with higher baseline logMAR VA (per 0.1 unit increase in logMAR) were more likely to have visual improvement postoperatively (FECD: RR, 0.82, 95% CI, 0.81-0.84; BK: RR, 0.91, 95% CI, 0.91-0.92), whereas postoperative rebubbling (FECD: RR, 1.10, 95% CI, 1.02-1.19; BK: RR, 1.31, 95% CI, 1.17-1.48) and repeat keratoplasties (FECD: RR, 1.41, 95% CI, 1.32-1.52; BK: RR, 1.42, 95% CI, 1.28-1.57) were associated with higher risk of no VA improvement. CONCLUSIONS: In this large national cohort, postoperative rebubblings and repeat keratoplasties were identified as independent factors associated with worse VA outcomes after EK for both FECD and BK subgroups. Older age and female gender were associated with worse VA outcomes after EK in the FECD subgroup.

Pediatric endothelial keratoplasty: a systematic review and individual participant data meta-analysis.

BACKGROUND: Recently, endothelial keratoplasty (EK) has been increasingly considered the first intervention in pediatrics with isolated corneal endothelial dysfunction. This systematic review aims to investigate the current evidence about the advantages, disadvantages, technical challenges, and clinical outcomes of EK in the pediatric group. METHOD: All the English literature relevant to pediatric EK was searched in PubMed, Embase, Scopus, and Cochrane databases with appropriate keywords. Relevant data were pooled to conduct an individual participant data meta-analysis. RESULTS: Of 1646 articles found initially, 35 articles were finally eligible to be included in our study. A total of 154 eyes of 107 patients underwent Descemet's stripping automated endothelial keratoplasty (DSAEK). Congenital hereditary endothelial dystrophy (CHED) was the most reported indication for pediatric DSAEK (108 eyes). Descemet's membrane endothelial keratoplasty (DMEK) was performed in 2 eyes of 2 cases, one with PPCD and another one in a patient with Kearns-Sayre syndrome. Owing to some specific anatomical and physiological pediatric characteristics, some modifications in a standard procedure were suggested. The average follow-up period was 23.80 ± 20.18 months (3 months to 8.5 years). Seventy-six eyes who had a mean best-corrected visual acuity (BCVA) of 1.36 ± 0.70 (0.49 to 3) logMAR preoperatively found mean BCVA of 0.51 ± 0.33 (0.04 to 2) logMAR postoperatively. Graft dislocation was the most reported complication (26 eyes). The rate of other complications was low. Endothelial cell loss was reported from 8.3 to 63.7% after pediatric EK with follow-up duration from 3 months to 8.3 years. CONCLUSION: EK procedures, despite some technical challenges, are feasible surgical techniques with acceptable visual and anatomical outcomes in the management of pediatrics with corneal endothelial dysfunction and minimal stromal involvement.

Management of lenticule detachment and epithelial downgrowth after Descemet stripping automated endothelial keratoplasty: a novel technique and brief literature review.

BACKGROUND: Epithelial downgrowth is a rare complication after Descemet stripping automated endothelial keratoplasty (DSAEK), which usually leads to poor visual outcome despite multiple available options of treatment. CASE PRESENTATION: A 50-year-old man underwent DSAEK procedure due to pseudophakic bullous keratopathy. Three months later, the patient presented with gradual visual loss; slit-lamp examination revealed detachment and folding of the DSAEK lenticule, which was confirmed by anterior segment optical coherence tomography. On confocal scanning, epithelial cell sheets were detected in the interface leading to the wrinkling of the donor tissue and donor detachment. Surgical debridement and transient fixating with straight 10-0 prolene needles were performed followed by air injection into the anterior chamber. The cornea turned clear in the one-year follow-up with uncorrected-visual acuity of 20/30 and best-corrected visual acuity of 20/25. CONCLUSIONS: Early diagnosis and treatment of epithelial downgrowth may be associated with a good prognosis and prevent from more aggressive treatments such as repeat of grafting. In this case, mechanical debridement and transient fixation of lenticule by 10-0 prolene needles was performed to manage post-DSAEK epithelial downgrowth and lenticule detachment, which was successful without requiring of additional re-grafting. It seems this is a feasible technique with acceptable long-term outcomes.

Nomogram for single-pass automated microkeratome graft preparation for ultrathin Descemet stripping automated endothelial keratoplasty.

PURPOSE: To create a nomogram including the translational speed of the microkeratome blade, microkeratome head size and precut tissue thickness to predict the postcut thickness for Descemet stripping automated endothelial keratoplasty to obtain the thinnest possible graft. METHODS: This prospective study incorporated 48 grafts for DSAEK from March 2017 to June 2020. Corneal tissue for DSAEK was prepared by 3 experienced physicians using the Moria Evolution 3E (Moria Inc, Antony, France) microkeratome with 400, 450 and 500 µm head sizes. Precut central corneal thickness was measured with a DGH 550 handheld pachymeter (Pachette 2), taking an average of 3 readings. The microkeratome head was selected according to precut tissue thickness. The selected microkeratome head size was 150 µm less than the donor cornea thickness. Two translational speeds were used for the microkeratome cuts. One month after surgery, the central lenticular thickness was measured with a Visante® Optical Coherence Tomography caliper (Carl Zeiss Meditec Inc, Germany). A descriptive analysis was performed. RESULTS: Forty-eight donor grafts were prepared. Mean graft thickness was 97.58 ± 29.84 µm (range 39-176 µm). Of the 48 samples, central graft thickness was < 120 µm (81.3%) in 39, < 100 µm (58.3%) in 28 and < 80 µm (37.5%) in 18 at 1-month follow-up. There were no statically significant differences between translational speeds. CONCLUSIONS: A nomogram with an automated microkeratome to obtain thin grafts for DSAEK provided good graft thickness results without donor waste.

[Morphological features of the cornea in eyes with pseudophakic bullous keratopathy and Fuchs endothelial corneal dystrophy]. / Morfologicheskie osobennosti rogovitsy pri psevdofakichnoi bulleznoi keratopatii i endotelial'noi distrofii Fuksa.

PURPOSE: To evaluate the morphological features of posterior corneal layers in pseudophakic bullous keratopathy (PBK) and Fuchs endothelial corneal dystrophy (FECD). MATERIAL AND METHOD: The study included 20 patients (20 eyes) aged 73.8±7.8 with PBK and 24 patients (25 eyes) aged 72.5±10.6 with FECD. Central corneal thickness was measured in all eyes before the surgery by anterior segment optical coherence tomography (AS-OCT, RTVue-100, Optovue, USA). All patients underwent corneal transplantation (DSAEK or DMEK). Postoperative donor graft status was assessed as attached or detached by AS-OCT (RTVue-100, Optovue, USA). Specimens of Descemet's membranes (DMs) were obtained intraoperatively and investigated histologically (hematoxylin and eosin staining). Morphometric analysis was performed using optical microscope Leica DM-2500 (Digital Color Camera Leica DFC295) and ImageScope M software. RESULTS: There was no difference in thickness of DMs' prenatal anterior banded layer (2.58±0.49 µm) and postnatal posterior non-banded layer (11.30±2.64 µm) between PBK and normal cornea. In FECD eyes, DM was significantly thickened by additional collagen layer and guttate excrescences (postnatal layer thickness - 16.62±4.34 µm). Morphological study of the DMs of patients with graft detachment in the early postoperative period revealed residual stromal collagen fibrils that were fixed to the area with dense extracellular matrix. CONCLUSION: The study shows that chronic corneal edema is associated with pathological morphological changes in the posterior corneal layers in PBK and FECD. Individual features of the dense extracellular matrix in the DMs may play a key role in the attachment of donor graft to the corneal stroma and affect the postoperative outcome.

[Morphological characteristics of Descemet's membrane removed during endothelial keratoplasty (case study)]. / Morfologicheskie osobennosti udalennoi pri endotelial'noi keratoplastike destsemetovoi membrany (klinicheskie nablyudeniya).

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.

Ultra-thin DSAEK using an innovative artificial anterior chamber pressuriser: a proof-of-concept study.

PURPOSE: To report the impact of establishing and maintaining a high intracameral pressure (ICP) of 200 mmHg on UT-DSAEK graft preparation using an artificial anterior chamber pressuriser (ACP) control unit (Moria SA, Antony, France). METHOD: Retrospective laboratory and clinical study. Four paired donor corneas were mounted on an artificial anterior chamber and subjected to 70 mmHg ("low") and 200 mmHg ("high") ICP using an ACP system. The central corneal thinning rate was measured after 5 min using AS-OCT and the endothelial cell viability was analysed using trypan blue and live/dead staining following 70 mmHg and 200 mmHg ICP. Visual outcomes and complications in a clinical case series of nine patients with bullous keratopathy who underwent UT-DSAEK using 200 mmHg ICP during graft preparation are reported. RESULTS: Laboratory outcomes showed 2 ± 1% and 2 ± 2% dead cells following 70 mmHg and 200 mmHg ICP respectively. Percentage viability in the 70 mmHg group (52.94 ± 5.88%) was not found to be significantly different (p = 0.7) compared to the 200 mmHg group (59.14 ± 10.43%). The mean corneal thinning rate after applying 200 mmHg ICP was 27 ± 13 µm/min centrally (7.2%/min). In the clinical case series, two cases were combined with cataract surgery. Re-bubbling rate was 11%. At the last follow-up (259 ± 109 days), graft thickness was 83 ± 22 µm centrally, endothelial cell density was 1175 ± 566 cell/mm2 and the BCVA of 0.08 ± 0.12 logMAR was recorded with no episodes of rejection. CONCLUSION: ACP control unit for UT-DSAEK graft preparation helps in consistently obtaining UT-DSAEK grafts without compromising endothelial cell viability.

Intraoperative optical coherence tomography guided corneal sweeping for removal of remnant Interface fluid during ultra-thin Descemet stripping automated endothelial keratoplasty.

BACKGROUND: Remnant interface fluid following Descemet stripping automated endothelial keratoplasty (DSAEK) is associated with postoperative detachments. The aim of this study was to assess outcomes of intraoperative optical coherence tomography (iOCT) guided meticulous peripheral corneal sweeping for removal of interface fluid during ultra-thin (UT) DSAEK. METHODS: This retrospective study included all eyes underwent iOCT guided UT-DSAEK from October 2016 to February 2018 at the Hanusch Hospital, Vienna, Austria. Peripheral meticulous corneal sweeping was performed to remove excess fluid. Central graft thickness (CGT) was measured prior to surgery, after graft bubbling and after corneal sweeping. Remnant interface fluid rates were compared between eyes that underwent rebubbling and those that did not. RESULTS: Overall, 28 eyes of 28 patients with a mean age of 73.9 ± 10.0 years were included. An iOCT guided meticulous peripheral sweeping was performed in 89.3% (n = 25) of the cases. Following 84% (n = 21) of the peripheral sweeping performed, remnant fluid was no longer identified. Following peripheral sweeping the interface fluid height was reduced from 17.31 ± 15.96 µm to 3.46 ± 9.52 µm (p < 0.001) and CGT was reduced by 7% (p < 0.001). Rebubbling was performed in 17.9% (n = 5) of the cases. The rebubbling group had a greater proportion of patients that had remnant fluid identified with iOCT at the end of surgery despite meticulous peripheral sweeping (60.0% versus 4.4%, p = 0.01). CONCLUSION: The iOCT identified subclinical remnant fluid in nearly 90% of UT-DSAEK cases. An iOCT guided peripheral corneal sweeping led to resolution of interface fluid in a majority of cases. Eyes with persistent remnant fluid despite peripheral corneal sweeping are more likely to require subsequent rebubbling.

Cost analysis of eye bank versus surgeon prepared endothelial grafts.

BACKGROUND: Selective lamellar corneal transplantation (keratoplasty) has overtaken full thickness penetrating keratoplasty as the graft choice for endothelial failure. Even more recently eye bank prepared tissues are becoming increasing popular as a way to reduce the risks of tissue loss and stress during endothelial keratoplasty preparation in the surgical theatre. This study compares costs between surgeon and eye bank prepared tissues for Descemet's stripping automated endothelial keratoplasty (DSAEK) and Descemet's membrane endothelial keratoplasty (DMEK). METHODS: Retrospective study conducted at the Royal Liverpool University Hospital including endothelial keratoplasties with a minimum of 6 months follow-up time. Cost analysis included surgical expenses, tissue acquisition fees, cost of patient's ward admission and out-patient expenses, including cost of re-bubbling procedures, costs of visits, anterior segment imaging and optometrist visits within the first 6 months follow-up. RESULTS: Ninety-eight eyes of 98 patients were included in the study of which 42 underwent DSAEK surgery and 56 DMEK surgery. Cost analysis of surgical expenses in the DSAEK group showed a significant difference between using surgeon prepared and eye bank prepared tissue (£3866 ± 296 and £4389 ± 360, respectively; p < 0.01) and the same was found in the DMEK group (£3682 ± 167 and £4162 ± 167 for surgeon prepared and eye bank prepared tissues, respectively; p < 0.01). Cost of out-patient visits did not differ significantly in either group. CONCLUSIONS: At the Royal Liverpool University Hospital, eye bank prepared tissues had higher surgical expenses compared to those prepared by the surgeon, while the post-operative care expenses were similar between the two groups.

Bilateral Ultrathin Descemet's Stripping Automated Endothelial Keratoplasty vs. Bilateral Penetrating Keratoplasty in Fuchs' Dystrophy: Corneal Higher-Order Aberrations, Contrast Sensitivity and Quality of Life.

Background and Objectives: The objective of this paper is to compare the visual outcomes and quality of life (QoL) after bilateral ultrathin Descemet's stripping automated endothelial keratoplasty (UT-DSAEK) with bilateral penetrating keratoplasty (PK) for Fuchs' endothelial dystrophy (FED). Materials and Methods: Retrospective comparative cohort study, including 11 patients with FED who underwent bilateral PK and 13 patients with FED who underwent bilateral UT-DSAEK. All patients were already pseudophakic or had undergone a combined cataract procedure. The main outcomes were corrected distance visual acuity (CDVA) corneal higher-order aberrations (HOAs), contrast sensitivity (CS) and quality of life (QoL). Results: The mean follow-up after the second eye surgery was 32.5 ± 10.2 months in PK and 19.6 ± 8.6 months in UT-DSAEK patients. The CDVA in the UT-DSAEK group was significantly better than in the PK one (0.18 ± 0.07 vs. 0.35 ± 0.16 logMAR, p < 0.0001). The mean anterior corneal total HOAs of the central 5 mm were significantly lower in UT-DSAEK eyes than in PK eyes (0.438 ± 0.078 µ and 1.282 ± 0.330 µ respectively, p < 0.0001), whilst the mean posterior total HOAs did not differ between groups (0.196 ± 0.056 µ and 0.231 ± 0.089 µ, respectively, p = 0.253). The CS was lower at 0.75 and 1.5 cycles/degree in P the K group when compared to the DSAEK one (p = 0.008 and 0.005, respectively). The QoL scores by the NEI RQL-42 test exhibited better values in DSAEK patients in 9 out of 13 scales. Conclusion: Our study confirms that UT-DSAEK provides a better visual function in terms of CDVA and CS, together with lower HOAs, when compared to PK. Hence, the vision-related QoL, binocularly evaluated by the NEI RQL-42 items, indicates a higher satisfaction in UT-DSAEK eyes.

Corneal densitometry patterns in Descemet membrane endothelial keratoplasty and Descemet stripping automated keratoplasty.

PURPOSE: To compare corneal densitometry in a consecutive series of 52 endothelial keratoplasties (DMEK/DSAEK) using a Scheimpflug-based device after six months of follow-up. METHODS: Corneal densitometry (CD) values of 102 eyes were divided into three main groups: 33 DMEKs, 19 DSAEKs, and 50 healthy eyes without previous ocular surgery. The CD values were then analyzed and compared between the groups. We measured three main layers in depth and four different concentric zones at 1, 3, and 6 months postoperatively. RESULTS: In the DMEK group, total CD significantly decreased from 38.02 ± 10.21 grayscale units (GSU) to 31.13 ± 9.25 GSU (P < 0.01) between the first and the sixth month postoperative. In the DSAEK group, we found significant changes only between the first and three months after surgery (from 42.62 ± 9.31 GSU to 38.71 ± 10.53 GSU (P < 0.01). Regarding the concentric zones, CD in the DMEK group significantly decreased in the central zone from 33.55 ± 12.07 GSU to 30.63 ± 10.15 GSU (P < 0.01) and significantly increased in the periphery from 30.63 ± 10.15 GSU to 36.72 ± 9.37 GSU, (P < 0.01). The DSAEK group showed no changes in the central zone (from 36.91 ± 13.80 GSU to 36.14 ± 11.47 GSU, P = 0.52) and CD significantly increased in the periphery (41.91 ± 9.28 GSU, P < 0.01). CONCLUSION: When comparing CD values in DMEK versus DSAEK, we found no differences by layers or at central-paracentral concentric zones, although CD differences in the peripheral zones were statistically significant. This finding may be attributed to the thicker graft at periphery with a delayed clearance and less anatomical interphase in DSAEK.

DSAEK or DMEK for failed penetrating keratoplasty: a systematic review and single-arm meta-analysis.

PURPOSE: To review the published literature on indications and outcomes of DSAEK/DSEK and DMEK for the treatment of failed penetrating keratoplasty. DESIGN: This is a systematic review and single-arm meta-analysis. METHODS: Literature searches were conducted in PubMed, Embase, Web of Science, and the Cochrane Database of Systematic Reviews. Prospective and retrospective studies reporting DSAEK/DSEK or DMEK after failed penetrating keratoplasty were included. Primary outcome measures are graft survival and detachment rates, as well as postoperative visual outcomes. RESULTS: A total of 25 studies with 970 patients/989 eyes were included, comprising 735 patients with 746 eyes which underwent DSAEK/DSEK surgery and 235 patients with 243 eyes which underwent DMEK surgery, all of them following a previously failed PK. There were no randomized controlled studies. In all of the DSAEK-PK studies, the graft failure rate was 18% (10%, 26%), the detachment rate was 15% (9%, 22%) and the rejection rate was 7% (3%, 12%) by the time of the last follow-up. And in all of the DMEK-PK studies, the graft failure rate was 14% (4%, 27%), the detachment rate was 42% (28%, 56%) and the rejection rate was 7% (2%, 16%). The mean visual acuity of the DSAEK-PK and DMEK-PK groups is 0.65 ± 0.18 and 0.43 ± 0.23 logMAR, respectively, at 6 months postoperatively. CONCLUSIONS: Endothelial keratoplasty for treatment of failed penetrating keratoplasty led to improved vision and graft clarity in most recipients. Though graft survival rates and rejection rates were comparable between the two groups, the DMEK-PK group showed better visual outcomes with higher detachment rate.

Secondary DMEK following failed primary DMEK.

PURPOSE: To report the outcomes of secondary Descemet Membrane Endothelial Keratoplasty (DMEK) performed for failed primary DMEK. METHODS: The medical records of all patients undergoing secondary DMEK due to failure of primary DMEK were reviewed. Reasons for failure were sought and best-corrected visual acuity (BCVA), endothelial cell density (ECD) and complications of secondary DMEK were evaluated. RESULTS: A total of 10 cases undergoing secondary DMEK following failed primary DMEK were identified. Presumed reasons for failure included donor ECD ≤ 2300 cells/mm2 (n = 4), difficulty during graft preparation (n = 2), graft detachment (n = 2), acute angle closure due to retroiridal air dislocation (n = 1), inverse graft positioning (n = 1) and phacoemulsification (n = 1). Eyes with low visual potential were not excluded from the study group. We should note that one patient (case no7) had both low ECD and graft detachment as reasons for failure and as a result he is counted twice. Median BCVA (decimal fraction) increased from 0.1 (range, 0.01; 0.3) to 0.5 (0.05; 1.0) at one month and remained stable thereafter. A BCVA of 0.5 or higher was achieved in 7 cases at the final follow-up. Mean ECD fell from 2628 ± 284 cells/mm2 to 1391 ± 252cells/mm2 at 6 months (47% reduction) and 959 ± 225cells/mm2 at 24 months (64% reduction) (P ≤ 0.028). Complications included the incomplete removal of the primary graft and mild iris bleeding, decompensation of a preexisting primary open-angle glaucoma and retroiridal air dislocation. CONCLUSIONS: Apart from low donor ECD, surgical challenges, i.e., difficulty with graft preparation, inverse graft positioning, and retroiridal air dislocation, were main reasons for failure of primary DMEK. Secondary DMEK showed a good safety profile and reasonable visual outcomes.

[Comparative assessment of functional outcomes of different endothelial keratoplasty techniques]. / Sravnitel'naya otsenka funktsional'nykh rezul'tatov razlichnykh tekhnologii endotelial'noi keratoplastiki.

PURPOSE: Comparative analysis of the higher-order aberrations (HOA) of the cornea after endothelial keratoplasty (EK) using DSAEK and DMEK techniques; evaluation of the correlation between higher-order corneal aberrations and functional outcomes of the treatment. MATERIAL AND METHODS: The study included 47 patients (59 eyes). The main group consisted of 35 patients (35 eyes) with bullous keratopathy and Fuchs' endothelial dystrophy; among them, 19 patients underwent endothelial keratoplasty using the DSAEK technique and 16 - DMEK technique. The control group included 12 patients (24 eyes) of corresponding age without corneal pathology. Standard and special examination tests were performed before, as well as 6 and 12 months after the operation, including computed tomography and aberrometry of the cornea using the Pentacam HR system. Same tests were performed in the control group. RESULTS: The values of the main HOA of the anterior corneal surface: RMS coma (Z3±1, Z5±1), RMS spherical aberration (SA; Z40, Z60) and RMS HOA (Z3-6) 6 months after different EK techniques were statistically significantly higher than in the control group. A statistically significantly lower induction of aberrations of the posterior corneal surface after DMEK technique was revealed. Analysis of the final aberration pattern 6 months after surgery did not reveal any statistically significant differences in the values of the main (RMS coma, RMS SA, RMS HOA) total corneal aberrations after DSAEK and DMEK. A negative correlation was revealed between the best corrected visual acuity (BCVA) and HOA; however, it was statistically significant only for individual aberration values: RMS HOA (Z3-6) of the posterior corneal aberrations after DMEK (r= -0.634, p=0.049), and RMS coma (Z3±1, Z5±1) of the cornea after DSAEK (r= -0.57, p=0.042). CONCLUSION: Comparative analysis of total corneal HOA did not reveal a statistically significant difference in the main parameters: RMS coma, RMS SA, RMS HOA in patients after DSAEK and DMEK surgeries. Correlation analysis did not reveal any statistically significant effects of most aberrations on the functional outcomes of the treatment.

An endothelial rejection line following Descemet stripping automated endothelial keratoplasty.

BACKGROUND: The endothelial rejection line is rarely seen after Descemet stripping automated endothelial keratoplasties (DSAEKs). Here, we present a case of endothelial graft rejection with an endothelial rejection line occurring 1 year after the procedure. CASE PRESENTATION: A 58-year-old female presented with graft rejection 1 year following a DSAEK procedure. The episode started when she tapered down her loteprednol to once a day. Slit-lamp examination showed a mildly injected conjunctiva with 1+ corneal oedema. On the posterior surface of the cornea, there was an endothelial rejection line (Khodadoust line) with keratic precipitates and multiple areas of anterior synechia. CONCLUSION: The classic endothelial rejection line should be kept in mind as a rare sign of DSAEK graft rejection.

Proposed risk factors for failure of transplanted eye bank-prepared descemet stripping automated endothelial keratoplasty tissues.

To investigate the possible risk factors for failure of transplanted eye bank-prepared Descemet stripping automated endothelial keratoplasty (DSAEK) tissues. In a retrospective study between March 2011 and March 2019, all the failed DSAEK cases (131 cases) reported to the Central Eye Bank of Iran were compared with a surgeon-matched successful DSAEK group (control, 126 cases) in terms of the donor, DSAEK tissue, and recipient characteristics. Univariate analysis indicated that the DSAEK tissue preparation from excised corneoscleral tissues (OR 2.17; P = 0.026) and donor conjunctival hyperemia (OR 1.62; P = 0.042) were more common in the re-DSAEK group than in the controls. Other donor and recipient characteristics as well as other DSAEK tissue criteria were not significantly different between the re-DSAEK and control groups. DSAEK lenticules in both re-DSAEK and control groups demonstrated symmetric contours. Subgroup analyses in the re-DSAEK group revealed a higher rate of surgeons' low to moderate experience in comparison to those of high experience (P < 0.001). Additionally, failed DSAEK was observed more commonly in donors aged over 50 years than among those under 30 years (P < 0.001). Our study showed that DSAEK tissues prepared from excised corneoscleral tissues and from donors with conjunctival hyperemia were associated with higher rates of re-DSAEK due to failed DSAEK. An increasing trend of re-DSAEK was observed with shorter surgeons' experience and more advanced donor's age.

[Analysis of light scattering ability of the cornea before and after endothelial keratoplasty]. / Analiz svetorasseivayushchei sposobnosti rogovitsy do i posle endotelial'noi keratoplastiki.

PURPOSE: To evaluate light scattering ability of the cornea before and after Descemet's stripping automated endothelial keratoplasty (DSAEK) and Descemet's membrane endothelial keratoplasty (DMEK) endothelial keratoplasty. MATERIAL AND METHODS: The study included 70 patients (70 eyes) who had undergone DSAEK and DMEK (35 patients, 35 eyes in each group). In addition to standard ophthalmological examinations before and during the one-year follow-up after surgery, the patients had their central corneal thickness, stromal thickness, thickness of the interface area and the graft measured with optical coherence tomography (Optovue, U.S.A.). Intensity of light scattering by corneal structures was evaluated using Pentacam HR (Oculus, Germany) topographer with proprietary software and algorithms for calculation of corneal transparency. RESULTS: Comparison of the outcomes revealed that indices of general integral and stromal light-scattering were higher in patients after DSAEK. Integral light scattering in the interface and graft areas in the DMEK group was significantly lower than in the DSAEK group during the whole follow-up period. CONCLUSION: The reason for decrease of visual acuity after endothelial keratoplasty, regardless of the surgery type, may be higher light-scattering ability of patient's corneal stroma due to residual opacifications. Better visual acuity outcomes after DMEK in comparison to DSAEK are associated with higher transparency of the interface and graft areas. The suggested new method of assessing the intensity of light-scattering allows more precise evaluation of the influence of light-scattering ability of the stroma, interface and corneal graft after different modifications of endothelial keratoplasty, considering the respective layer thickness and excluding the influence of light scattering on the air-epithelium interface.