A 10-year review of underlying diseases for endothelial keratoplasty (DSAEK/DMEK) in a tertiary referral hospital in Japan

Risk factors for intraocular pressure elevation following Descemet membrane endothelial keratoplasty in Asian patients

PURPOSE

To investigate risk factors for increased intraocular pressure (IOP) after Descemet membrane endothelial keratoplasty (DMEK) in Asian patients.

METHODS

Data from January 2015 to February 2021 were obtained from our prospective database. IOP elevation after DMEK was defined as IOP ≥ 22 mmHg or an increase in IOP of ≥ 10 mmHg from baseline. In addition, we examined maximum IOP. Using iCare, we measured IOP 1, 2, 3, and 6 months after DMEK, and every 6 months thereafter. Logistic regression and linear regression were performed to find factors predictive of IOP elevation and maximum IOP, respectively, based on the results of univariate analysis.

RESULTS

We enrolled 90 eyes (mean patient age, 74.9 ± 7.5 years; mean follow-up duration, 25.6 ± 9.9 months) that underwent DMEK. IOP elevation was present in 19 eyes (21%). IOP increased from 12.6 ± 3.9 mmHg preoperatively to a postoperative maximum of 17.0 ± 5.5 mmHg up to 36 months after DMEK (p < 0.0001). In univariate logistic regression analysis for IOP elevation, only one variable, pseudoexfoliation syndrome (PEX) and preexisting glaucoma, was significant (p < 0.05). Preexisting glaucoma without PEX (OR, 19.33; 95% CI, 4.75-93.46), PEX without glaucoma (OR, 7.25; 95% CI, 1.20-41.63), and PEX glaucoma (OR, 58.00; 95% CI, 6.78-1298.29) were associated with higher risk of IOP elevation.

CONCLUSIONS

In this cohort, the eyes of patients with PEX and preexisting glaucoma were found to be prone to IOP elevation after DMEK.

Graft rejection episodes after keratoplasty in Japanese eyes

We aimed to investigate the clinical characteristics and risk factors for graft rejection after keratoplasty in Japanese patients. We enrolled 730 cases (566 patients) of penetrating keratoplasty (PK, N = 198), Descemet's stripping automated endothelial keratoplasty (DSAEK, N = 277), non-Descemet's stripping automated endothelial keratoplasty (nDSAEK, N = 138), and Descemet membrane endothelial keratoplasty (DMEK, N = 117). The incidence, clinical characteristics, and possible risk factors for graft rejection were analyzed. Graft rejection occurred in 65 cases (56 patients, 8.9%). The incidence rate of rejection was highest with PK (3.45/100 person-years), followed by DSAEK (2.34), nDSAEK (1.55), and DMEK (0.24). Cox regression analysis revealed keratoplasty type, younger age, indications (such as failed keratoplasty and infection), and steroid eyedrop use as possible risk factors. In the multivariate model adjusting baseline characteristics, PK and DSAEK had significantly higher hazard ratios (HRs) than DMEK (HR = 13.6, 95% confidence interval [CI] [1.83, 101] for PK, 7.77 [1.03, 58.6] for DSAEK). Although not statistically significant, the HR estimate of nDSAEK to DMEK (HR = 7.64, 95% CI [0.98, 59.6]) indicated higher HR in nDSAEK than in DMEK. DMEK is the favorable option among the four surgical procedures to avoid graft rejection after keratoplasty.

Clinical outcome of Descemet membrane endothelial keratoplasty (DMEK) with imported donor corneas in eyes of Asian patients; endothelium-in versus endothelium-out method

Objective

We investigated whether (1) imported pre-cut tissue is feasible for Descemet membrane endothelial keratoplasty (DMEK) in eyes of Asian patients, (2) the clinical outcome is comparable between the endothelium‐in and endothelium‐out methods, and (3) the corneal edema-induced anterior curvature changes may have an effect on the refractive error.

Methods

The medical records of 32 DMEK patients who underwent either the endothelium-out or endothelium-in method using imported pre-cut grafts with a 3-day pre-cut-to-use time were retrospectively analyzed. Fuchs’ endothelial dystrophy (37.5%) and bullous keratopathy (62.5%) cases were included. The main clinical outcome measures were graft survival, best corrected visual acuity (BCVA), endothelial cell density (ECD), corneal thickness (CT), and complications. Correlation of the anterior curvature changes with refractive error was analyzed in the DMEK with cataract surgery group.

Results

The overall survival rate was 71.9%. Final graft failures were caused by rejection, glaucoma, and infection. Visual acuities improved by 89.3%. BCVA better than 20/40 and 20/20 was found in 75% and 28.6% of patients, respectively. The ECDs at 3 months and 1 year were 1400 and 1083 cells/mm², respectively. The mean survival time, ECD, BCVA, CT, and complication rates were not different between the endothelium-in and endothelium-out methods. A hyperopic shift by +0.42 D was not related to the anterior curvature changes.

Conclusion

Imported pre-cut tissues with a ≤ 3-day pre-cut-to-use time are feasible for DMEK in the treatment of corneal endothelial edema in eyes of Asian patients, and both endothelium-in and endothelium-out methods appear to be comparatively effective. Edema-induced anterior curvature change may not affect the refractive shift.

Investigation of the Sectorized Corneal Thickness of Eyes With Corneal Endothelial Dysfunction Using Anterior-Segment Optical Coherence Tomography

PURPOSE

The aim of this study was to investigate the sectorized corneal thickness of eyes with corneal endothelial dysfunction using anterior-segment optical coherence tomography.

METHODS

We retrospectively collected anterior-segment optical coherence tomography data conducted before endothelial keratoplasty on 53 eyes of 53 patients with corneal endothelial dysfunctions including Fuchs endothelial corneal dystrophy, bullous keratopathy (BK) after trabeculectomy, and BK after laser iridotomy and from 18 normal eyes of 18 subjects. The imaging points were divided into 17 sectors. The mean for each sector was calculated and compared with the corresponding superior/inferior and temporal/nasal sectors.

RESULTS

In the normal eyes, the superior sectors were thicker than the inferior and the temporal sectors thinner than the nasal. In the diseased eyes, the superior sectors were thicker than the inferior in all subgroups; however, this tendency was no longer observed after the values were divided by the mean for the normal eyes. No significant differences were found on horizontal comparisons; however, after the values were divided by the mean for the normal eyes, the temporal sectors were thicker than the nasal. When comparing the values between the with-hole and the without-hole sides in the BK after laser iridotomy eyes, the sectors on the with-hole side were thicker than the other side.

CONCLUSIONS

Corneal thickness of endothelial dysfunction was thicker in the superior sectors than the inferior but at a similar level to normal eyes. No significant differences were found for horizontal comparisons but, based on comparison with the normal eyes, the temporal sectors were thicker than the nasal.

Descemet membrane endothelial keratoplasty (DMEK) improves vision-related quality of life

Purpose

To evaluate vision-related quality of life (VRQL) before and after Descemet membrane endothelial keratoplasty (DMEK).

Methods

The study was conducted in patients with Fuchs endothelial dystrophy or pseudophakic bullous keratopathy undergoing DMEK alone or in combination with cataract surgery (triple-DMEK) between August 2019 and March 2020 at the University of Leipzig Medical Center. Best-corrected visual acuity (BCVA) was measured. Visual acuity factor (VAF) and glare factor (GF) scores were calculated using the Visual Function and Corneal Health Status Instrument questionnaire answered by patients before surgery and 6 months thereafter. Subgroup analyses were performed for DMEK versus triple-DMEK, and for first versus second eyes, in addition to correlation analyses of scores with preoperative BCVA.

Results

Forty-six patients were included in this analysis. VAF score improved from 0.68 ± 0.54 to 0.02 ± 0.57 (P < 0.0001) and GF score improved from 0.53 ± 0.43 to -0.11 ± 0.39 (P < 0.0001) during follow-up. Both scores improved without significant differences after surgery in the first and in the fellow eye (P < 0.0001) and after DMEK and triple-DMEK (P < 0.0001). The improvement of scores did not correlate with preoperative BCVA (r = 0.06, P = 0.68 for VAF; r =  -0.09, P = 0.54 for GF).

Conclusion

VRQL improves similarly after DMEK and triple-DMEK and between first and second operated eye. The extent of improvement is independent of the preoperative BCVA. The results of this study can be useful when planning DMEK by enabling a prediction of anticipated VRQL gain.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00417-022-05711-9.

Donor-Related Risk Factors for Graft Decompensation Following Descemet's Stripping Automated Endothelial Keratoplasty

Aims

To identify donor-related risk factors associated with graft endothelial failure and postoperative endothelial cell density (ECD) reduction after Descemet's stripping automated endothelial keratoplasty (DSAEK).

Methods

This was a single-center retrospective study conducted from July 2006-December 2016. We included 584 consecutive eyes (482 patients) that underwent DSAEK for the treatment of laser iridotomy-related bullous keratopathy (192 eyes), pseudophakic bullous keratopathy (137 eyes), regraft (96 eyes), Fuchs' endothelial corneal dystrophy (FECD; 59 eyes) and others (100 eyes). Twenty-three donor- and recipient-related risk factors potentially associated with graft failure and ECD reduction were assessed using Cox hazard models and linear mixed effect models.

Results

The median age of the patients was 73.5 years (male; 35.6%). After DSAEK, ECD decreased from 2,674 cells/mm2 (95% confidence interval [CI]; 2,646–2,701) to 1,132 (1,076–1,190) at 12 months and 904 (845–963) at 24 months (P &lt; 0.001). Fifty-five eyes (9.4%) had graft endothelial failure without rejection. This failure was associated with donor pseudophakic lens status (hazard ratio [HR]; 2.67, CI; 1.50–4.76, P = 0.001) and preoperative endothelial folds (HR; 2.82, CI; 1.20–6.62, P = 0.02). The incidence of graft endothelial failure in non-FECD patients was significantly higher among those receiving donor grafts with a pseudophakic lens status and preoperative presence of endothelial folds (P &lt; 0.001). Postoperative ECD loss was significantly greater in eyes with these risk factors compared to those without (P = 0.007).

Conclusions

Pseudophakic status and/or presence of preoperative endothelial folds are the significant donor risk factors for endothelial failure in non-FECD patients.

Association between aqueous humor cytokines and postoperative corneal endothelial cell loss after Descemet stripping automated endothelial keratoplasty

This study measured the intraoperative anterior aqueous humor concentrations of various cytokines during corneal endothelial transplantation and searched for relationships between these concentrations and postoperative corneal endothelial cell (CEC) depletion. We recruited 30 consecutive patients who underwent corneal endothelial transplantation with Descemet’s stripping automated endothelial keratoplasty (DSAEK) at Tohoku University Hospital between February 2014 and July 2017. During surgery, we obtained aqueous humor samples and later measured the concentrations of 27 cytokines with a Multiplex Bead Assay (Bio-Plex Pro). We counted CECs 1, 6 and 12 months after surgery, and used Spearman’s rank correlation coefficient to identify relationships between CEC depletion and the concentrations of detected cytokines. The loss of CECs 1–6 months after surgery was significantly correlated with IL-7, IP-10, MIP-1a and MIP-1b concentrations (-0.67, -0.48, -0.39, and -0.45, respectively, all P <0.01). CEC loss 1–12 months after surgery was significantly correlated with IL-1b, IL-7, IP-10 and RANTES concentrations (-0.46, -0.52, -0.48, and -0.43, respectively). Multiple regression analysis showed that IL-7 concentration was significantly associated with CEC loss 1–6 months after surgery (b = -0.65, P < 0.01) and IP-10 concentration was associated with CEC loss 1–12 months after surgery (β = -0.38, P < 0.05). These results suggest that not only inflammatory cytokines but also IL-7, a cytokine related to lymphocytes, may be involved in the depletion of CECs after DSAEK, particularly depletion that occurs relatively early.

Trends in surgical procedures and indications for corneal transplantation over 27 years in a tertiary hospital in Japan

PURPOSE

To characterize trends in procedures, and indications for corneal transplantation over 27 years in a single referral center in Japan.

STUDY DESIGN

Retrospective study.

METHODS

Data from a consecutive series of corneal transplant surgery cases performed from 1991 to 2017at Ichikawa General Hospital were collected. The surgical procedures, indications, and causes of corneal endothelial dysfunction were evaluated.

RESULTS

Among 6,025 transplantations, a total of 3,991 cases underwent penetrating keratoplasty (PKP), 1009 underwent (deep) anterior lamellar keratoplasty, 746 underwent endothelial keratoplasty, and 309 underwent epithelial transplantation. Over that period the frequency of PKP decreased, whereas the frequency of lamellar keratoplasty increased. The four major surgical indications were bullous keratoplasty (BK 30.0%), regraft (24.2%), post-keratitis scars (17.1%), and keratoconus (11.4%). After dividing the study period into four time periods, we found that BK and regraft increased (from 20.3% to 34.5% and 18.2% to 31.1%, respectively), whereas post-keratitis scars and keratoconus decreased (from 26.0% to 9.5% and 14.1% to 7.2%, respectively) between the first and last period. Pseudophakic or aphakic BK were the major causes of corneal endothelial dysfunction until 2010. Cases of laser-iridotomy-induced BK peaked in 35 eyes (34.3% of BK) in 2000 and declined after 2013. Cases of Fuchs endothelial corneal dystrophy increased from 0 in 1991, to 15 eyes (18.5% of BK) in 2017.

CONCLUSION

Lamellar keratoplasty has replaced PKP in our hospital. BK and regraft have increased, whereas post-keratitis scars and keratoconus have decreased. Laser-iridotomy-induced BK has decreased during the past decade, whereas Fuchs endothelial corneal dystrophy has increased.

Long-term outcomes of Descemet stripping automated endothelial keratoplasty for bullous keratopathy after argon laser iridotomy

PURPOSE

To report the long-term outcomes of Descemet stripping automated endothelial keratoplasty (DSAEK) for bullous keratopathy secondary to argon laser iridotomy (BK-ALI).

STUDY DESIGN

Retrospective chart review.

METHODS

Forty-five eyes from 41 consecutive patients with BK-ALI who underwent DSAEK from July 2007 to December 2013 were retrospectively analyzed. Best spectacle-corrected visual acuity (BCVA), endothelial cell density (ECD), and any complications were investigated over a 10-year postoperative period.

RESULTS

The mean BCVA improved from 0.80 logMAR before DSAEK to 0.28 logMAR at 6 months after DSAEK; the mean values showed an additional slight improvement between 6 months and 10 years after the surgery (P < .01). The mean ECD decreased from 2864 cells/mm² at baseline to 2269 cells/mm² (20.8% loss) at 6 months post-DSAEK, and this decreasing trend continued throughout the 10 years after DSAEK (P < .01). The mean ECD was 1148 cells/mm² (59.9% loss) after 5 years, and 568 cells/mm² (80.2% loss) after 10 years. No graft deaths were observed throughout the 10-year period (5-year follow-up rate 60.0%, 10-year follow-up rate 20.0%).

CONCLUSIONS

The 10-year outcomes of DSAEK for BK-ALI were excellent with a high graft survival rate.

Graft Edge Reflection of a Tightly Scrolled Roll Using Endoillumination as a Simple Method for Determining Graft Orientation in Descemet Membrane Endothelial Keratoplasty

PURPOSE

To describe a simple finding that can be used to determine donor tissue orientation in Descemet membrane endothelial keratoplasty (DMEK). This involves the appearance of a highly reflective round curved line from an overlapping graft edge within the anterior chamber using light from an endoilluminator. We here name this Kobayashi sign (K-sign).

METHODS

Twelve consecutive eyes from 12 patients who underwent DMEK were evaluated for the presence of a K-sign. The presence of Berrospi sign (B-sign), a double-line reflection from the peripheral curls of the Descemet membrane (DM) roll that has been reported to be useful for correct graft orientation, was also evaluated.

RESULTS

Of 12 cases, 3 donors showed a loosely scrolled roll soon after DM donor insertion; all 3 of these showed a positive B-sign only when the endoilluminator was used. Nine donors showed a tightly scrolled DM roll without a B-sign; among these 9 donors, a K-sign was visible in 7 cases only when the endoilluminator was used. The remaining 2 cases with a tight scroll configuration showed no K-sign even with the use of endoillumination, indicating that the roll edge was located completely downward; rotation of the roll using a small jet of fluid from paracentesis revealed K-sign in these cases.

CONCLUSIONS

This technique is useful for determining the correct orientation of a tightly scrolled DM roll, subsequently enabling rapid DMEK surgery. For loosely scrolled DM roll, endoillumination enhanced B-sing is proven useful.

Five-year follow-up outcomes after Descemet's stripping automated endothelial keratoplasty: a retrospective study

Objective

To assess graft survival and endothelial cell density (ECD) over a 5-year follow-up period after Descemet’s stripping automated endothelial keratoplasty (DSAEK).

Methods and analysis

This retrospective study involved 130 eyes of 130 consecutive patients with Fuchs endothelial corneal dystrophy (FECD), non-FECD bullous keratopathy (BK) (non-FECD) or BK post-trabeculectomy or tube-shunt surgery (glaucoma with bleb) who underwent DSAEK between August 2007 and January 2012 and were followed for more than 5 years postoperatively. Patients with previous keratoplasty, graft suture failure, primary graft failure, postoperative endophthalmitis and ocular infection were excluded. Graft survival and ECD was then examined in all patients who underwent DSAEK and completed the postoperative follow-up period. The association between clinical factors and 5-year graft survival after DSAEK was analysed with multivariate logistic regression analysis.

Results

The overall graft survival rate at 5 years postoperatively was 85%, yet significantly poorer in the glaucoma with bleb eyes (47%) than in the FECD (100%) or non-FECD (90%) eyes (p<0.01, log-rank test). In the FECD, non-FECD and glaucoma with bleb eyes, the mean ECD at 5 years postoperatively was 1054 cells/mm², 1137 cells/mm² and 756 cells/mm², respectively. Multivariate logistic regression analysis showed history of trabeculectomy or tube-shunt surgery and postoperative allograft rejection to be negative factors for graft survival at 5 years after DSAEK (OR 0.01, 95% CI 0.00 to 0.10 and OR 0.02, 95% CI 0.00 to 0.33, respectively).

Conclusion

Our findings show that at 5 years postoperatively, the surgical outcome after DSAEK was poorer in eyes after trabeculectomy or tube-shunt surgery.

Trial registration number

UMIN000024891.

Clinical Evaluation of the NS Endo-Inserter, a Novel Donor Inserter for Descemet's Stripping Automated Endothelial Keratoplasty

Purpose

This study investigated the clinical outcomes achieved with a newly developed donor inserter (NS Endo-Inserter [NSI], HOYA Co., Ltd., Tokyo, Japan) for Descemet's stripping automated endothelial keratoplasty (DSAEK) in Japanese eyes with bullous keratopathy secondary to argon laser iridotomy (BK-ALI). The NSI device utilizes pressure flow to push the DSAEK donor tissue into the anterior chamber.

Methods

Six eyes of 6 patients (1 male, 5 females; mean age, 78.5 years) with BK-ALI were enrolled. Donor tissue was pushed into the anterior chamber using the NSI. Intraoperative complications, graft dislocation, and iatrogenic primary graft failure were recorded for all eyes. Six-month postoperative central donor endothelial cell densities (ECD) were measured prospectively and compared with preoperative values, along with 6-month best corrected visual acuity (BCVA).

Results

In all cases, donor loading onto the NSI spatula and donor insertion into the anterior chamber using the NSI was smooth and successful; no intraoperative complications were noted. There were no cases of graft dislocation or IPGF. Postoperative ECD was 2,187.2 cells/mm² (mean loss, 14.8%) and mean BCVA increased from 0.27 decimal to 0.8 at 6 months.

Conclusion

In this small preliminary case series, clinical outcomes for patients with BK-ALI undergoing DSAEK using the NSI were comparable or better than those achieved with conventional DSAEK insertion techniques.

Changing indications and surgical techniques for keratoplasty during a 16-year period (2003-2018) at a tertiary referral hospital in Japan

Purpose

To present the changing indications and surgical techniques for keratoplasty during a 16-year period (2003–2018) at a tertiary referral hospital in Japan.

Methods

Consecutive keratoplasty cases at Kanazawa University Hospital from January 2003 to December 2018 were retrospectively reviewed. Keratoplasty procedures included penetrating keratoplasty (PK), deep anterior lamellar keratoplasty (DALK), anterior lamellar keratoplasty (ALK), Descemet’s stripping automated endothelial keratoplasty (DSAEK), and Descemet’s membrane endothelial keratoplasty (DMEK). Annual numbers and types of keratoplasty as well as underlying diseases for PK and total keratoplasty procedures were recorded, and annual trends were statistically analyzed using Cochran–Armitage test for trend.

Results

A total of 801 keratoplasty procedures (PK, 319 cases; DALK, 57 cases; ALK, 9 cases; DSAEK, 371 cases; and DMEK 45 cases; mean age, 66.9±16.3 years) were performed for 595 patients (302 males [329 eyes, 419 cases], 293 females [345 eyes, 382 cases]) during the 16-year period. The proportion of PK procedures decreased significantly in the beginning and showed a slightly increasing trend after a plateau around 2015. DSAEK was increasing after 2006 and reached a plateau around 2012. Among 10 underlying diseases for total keratoplasty, corneal opacity and dermoid were decreasing linearly. Failed PK and failed DSAEK were increasing linearly in the beginning and reached a plateau followed by a decreasing trend. In terms of the underlying disease for PK, bullous keratopathy was decreasing in the beginning and reached a plateau around 2015. A total of 19 PK procedures were performed on cases with recalcitrant bullous kerstopathy (BK) after 2010.

Conclusion

The distribution of keratoplasty procedures and underlying diseases changed significantly over 16 years at a tertiary referral hospital in Japan. PK procedure was significantly decreased and DSAEK procedure was significantly increased. PK for BK decreased significantly; however, PK remains a viable option for other recalcitrant corneal diseases.

Fuchs endothelial corneal dystrophy and corneal endothelial diseases: East meets West

Fuchs endothelial corneal dystrophy (FECD) is amongst one of the most common indications for endothelial keratoplasty worldwide. Despite being originally described among Caucasians, it is now known to be prevalent among a large number of populations, including Asians. While the FECD phenotype is classically described as that of central guttate and pigment deposits associated with corneal endothelial dysfunction, there are subtle yet important differences in how FECD and its phenocopies may present in Caucasians vs Asians. Such differences are paralled by genotypic variations and disease management preferences which appear to be geographically and ethnically delineated. This article provides a succinct review of such differences, with a focus on diagnostic and management issues which may be encountered by ophthalmologists practicing in the different geographic regions, when evaluating a patient with FECD.