Descemet's stripping automated endothelial keratoplasty with anterior chamber intraocular lenses: complications and 3-year outcomes

Outcomes of Secondary Intraocular Lens Implantation and Descemet Stripping Endothelial Keratoplasty-Comparing Staged Versus Combined Surgical Approach

PURPOSE

The aim of this study was to compare the outcomes of staged versus combined surgical approach for secondary intraocular lens (IOL) implantation and Descemet stripping endothelial keratoplasty (DSEK).

METHODS

This is a retrospective review of 124 eyes from 124 patients who underwent either staged or combined secondary IOL implantation in addition to DSEK over a 5-year period at 2 academic tertiary referral centers, between January 1, 2014, and October 1, 2019. Corrected distance visual acuity (CDVA), presence of graft detachment, primary graft failure (PGF), and cystoid macular edema were documented and analyzed.

RESULTS

The CDVA for the 1- to 2- month follow-up period was significantly better in the staged group compared with the combined group ( P = 0.011). By the postoperative 6- to 9-month follow-up period, there was no significant difference in the CDVA between the groups ( P = 0.591). There was no significant difference in the incidence of PGF or graft detachment between the 2 groups ( P > 0.05). In addition, there was no significant difference in the CDVA or rate of postoperative complications between the different methods of IOL fixation.

CONCLUSIONS

The short-term visual outcomes were significantly better in eyes that underwent staged secondary IOL implantation and DSEK versus the combined surgical approach, although the difference was no longer present at 6 to 9 months. There was no difference in the rate of PGF or graft detachment between the 2 groups.

Big data in corneal diseases and cataract: Current applications and future directions

The accelerated growth in electronic health records (EHR), Internet-of-Things, mHealth, telemedicine, and artificial intelligence (AI) in the recent years have significantly fuelled the interest and development in big data research. Big data refer to complex datasets that are characterized by the attributes of "5 Vs"-variety, volume, velocity, veracity, and value. Big data analytics research has so far benefitted many fields of medicine, including ophthalmology. The availability of these big data not only allow for comprehensive and timely examinations of the epidemiology, trends, characteristics, outcomes, and prognostic factors of many diseases, but also enable the development of highly accurate AI algorithms in diagnosing a wide range of medical diseases as well as discovering new patterns or associations of diseases that are previously unknown to clinicians and researchers. Within the field of ophthalmology, there is a rapidly expanding pool of large clinical registries, epidemiological studies, omics studies, and biobanks through which big data can be accessed. National corneal transplant registries, genome-wide association studies, national cataract databases, and large ophthalmology-related EHR-based registries (e.g., AAO IRIS Registry) are some of the key resources. In this review, we aim to provide a succinct overview of the availability and clinical applicability of big data in ophthalmology, particularly from the perspective of corneal diseases and cataract, the synergistic potential of big data, AI technologies, internet of things, mHealth, and wearable smart devices, and the potential barriers for realizing the clinical and research potential of big data in this field.

“Endothelium-Out” and “Endothelium-In” Descemet Membrane Endothelial Keratoplasty (DMEK) Graft Insertion Techniques: A Systematic Review With Meta-Analysis

Background

We evaluated the visual outcomes and complications of “endothelium-out” and “endothelium-in” Descemet membrane endothelial keratoplasty (DMEK) graft insertion techniques.

Materials and Methods

Electronic searches were conducted in CENTRAL, Cochrane databases, PubMed, EMBASE, ClinicalTrials.gov. Study designs included clinical trials, comparative observational studies, and large case series (≥25 eyes). PRISMA guidelines were used for abstracting data and synthesis. Random-effects models were employed for meta-analyses.

Results

21,323 eyes (95 studies) were included. Eighty-six studies reported on “endothelium-out” techniques; eight studies reported on “endothelium-in” techniques. One study compared “endothelium-out” to “endothelium-in” techniques. Eighteen “endothelium-out” studies reported that 42.5–85% of eyes achieved best-corrected visual acuity (BCVA) ≥20/25 at 6 months; pooled proportion of eyes achieving BCVA ≥20/25 at 6 months was 58.7% (95% CI 49.4–67.7%,15 studies). Three “endothelium-in” studies reported that 44.7–87.5% of eyes achieved BCVA of ≥20/25 at 6 months; pooled proportion of eyes achieving BCVA ≥20/25 at 6 months was 62.4% (95% CI 33.9–86.9%). Pooled mean endothelial cell loss was lower in the “endothelium-in” studies (28.1 ± 1.3%, 7 studies) compared to “endothelium-out” studies (36.3 ± 6.9%,10 studies) at 6 months (p = 0.018). Graft re-bubbling rates were higher in the “endothelium-out” studies (26.2%, 95% CI 21.9–30.9%, 74 studies) compared to “endothelium-in” studies (16.5%, 95% CI 8.5–26.4%, 6 studies), although statistical significance was not reached (p = 0.440). Primary graft failure rates were comparable between the two groups (p = 0.552). Quality of evidence was considered low and significant heterogeneity existed amongst the studies.

Conclusion

Reported rates of endothelial cell loss were lower in “endothelium-in” DMEK studies at 6 months compared to “endothelium-out” studies. Outcomes of “endothelium-in” techniques were otherwise comparable to those reported in “endothelium-out” studies. Given the technical challenges encountered in “endothelium-out” procedures, surgeons may consider “endothelium-in” techniques designed for easier intra-operative DMEK graft unfolding. “Endothelium-in” studies evaluating outcomes at longer time points are required before conclusive comparisons between the two techniques can be drawn.

Decompensated cornea with epithelial and stromal edema

A 66-year-old patient underwent surgery for congenital cataract in both eyes in her first year of life without implantation of an intraocular lens (IOL). In 1994, at the age of 39 years, both eyes received secondary Kelman multiflex-style angle-fixated anterior chamber IOLs (AC IOLs). The surgeries were followed by retinal detachments in both eyes, in the left eye in the same year and in the right eye 4 years later, which were successfully repaired. The patient presented with a decompensated cornea with epithelial and stromal edema in the left eye. The AC IOL axis was oriented from 5- to 8-o'clock position with the haptic contacting the cornea. The distal portion of the inferior-nasal haptic was deeply buried and entrapped in a broad iridocorneal synechia extending between 6- and 8-o'clock positions. The synechia also caused adjacent pupillary distortion and pigment leaf eversion (Figure 1JOURNAL/jcrs/04.03/02158034-202205000-00021/figure1/v/2022-04-22T173532Z/r/image-tiff). The AC IOL in the right eye was well positioned, and the cornea was clear with an endothelial cell count (ECC) of 2160 cells/mm2 and central corneal thickness (CCT) of 650 μm. No ECC was obtainable in the left eye, and CCT was 775 μm (Figure 2JOURNAL/jcrs/04.03/02158034-202205000-00021/figure2/v/2022-04-22T173532Z/r/image-tiff). Visual acuity was 0.8 corrected in the right eye and hand motion in the left eye. Both eyes were normotonic. On optical coherence tomography (OCT) imaging, a broad iridocorneal synechia was visible with a canal corresponding to the deeply buried haptic end of the AC IOL (Figure 3JOURNAL/jcrs/04.03/02158034-202205000-00021/figure3/v/2022-04-22T173532Z/r/image-tiff). Abundant condensed cortical material (Soemmerring's ring) was found behind the iris and above the ciliary body. What would be your surgical options to rehabilitate the patient's left eye considering corneal decompensation caused by haptic contact of an angle-fixated AC IOL and capture of 1 haptic within an iridocorneal synechia extending along 2 clock hours?

Preventive treatment of allograft rejection after endothelial keratoplasty: A systematic review and meta-analysis

PURPOSE

To evaluate the efficacy of preventive treatment against allograft rejection after endothelial keratoplasty (EK), we conducted a systematic review and meta-analysis.

METHOD

PubMed, Cochrane Library, Embase and ScienceDirect databases were searched until May 2021. We computed a random-effect meta-analysis on graft rejection rate stratified by the intervention (i.e. Descemet membrane EK (DMEK) and Descemet stripping (Automated) EK (DS(A)EK) or ultrathin (UT)-DSAEK), and postoperative treatment. Meta-regressions were performed to compare intervention, treatment and influence of putative confusion factors.

RESULTS

We included 49 studies and 12 893 EK (6867 DMEK and 6026 DS(A)EK/UT-DSAEK). Topical steroids were merged in two efficacy regimens: standard steroids (prednisolone acetate 1% or dexamethasone 0.1%) and soft steroids (fluorometholone 0.1% or loteprednol etabonate 0.5%). Globally, DMEK had a lower graft rejection rate than DS(A)EK/UT-DSAEK (coefficient - 3.3, 95 CI, -4.60 to -1.90; p < 0.001). No significant differences were observed between standard and soft steroids to prevent graft rejection after DMEK. After EK, the rate of ocular hypertension was 20% (95 CI, 14 to 26%) with the use of standard steroids and 7% (5 to 9%) with soft steroids. Comparisons of treatments were not feasible in DS(A)EK/UT-DSAEK due to a lack of studies.

CONCLUSIONS

Descemet membrane endothelial keratoplasty (DMEK) has less risk of graft rejection compared with DS(A)EK/UT-DSAEK. Furthermore, soft steroids seemed to be a valuable alternative to standard steroids to prevent graft rejection after DMEK, involving a safe profile against ocular hypertension. Further studies are needed to compare other drugs in the prevention of graft rejection after EK.

Corneal transplantation activity in Catalonia, Spain, from 2011 to 2018: Evolution of indications and surgical techniques

Purpose

To report corneal transplant activity carried out in Catalonia (Spain) and the evolving indications for keratoplasty over an 8-year period.

Methods

Annual reports from the Catalan Transplant Organization, Spain, on corneal graft indications and techniques from 2011 to 2018 were reviewed.

Results

A total of 9457 keratoplasties were performed in Catalonia, from January 2011 to December 2018. The most frequent indications were bullous keratopathy (BK; 20.5%), Fuchs endothelial dystrophy (FED; 17.9%), re-graft (13.7%), and keratoconus (11.3%). Penetrating keratoplasty (PKP) accounted for 63.4% of all performed keratoplasties. Since the introduction of eye bank precut tissue for Descemet stripping automated endothelial keratoplasty (DSAEK) in 2013 and for Descemet membrane endothelial keratoplasty (DMEK) in 2017 the number of endothelial keratoplasties has drastically increased. An increasing trend of posterior lamellar techniques over the total of keratoplasties was found (p<0.001). Endothelial keratoplasties for different endothelial diseases indications (BK, FED, and re-graft), also showed and increasing trend (p<0.001). DMEK is the technique with the highest increase (statistically significantly different from linearity) over other endothelial keratoplasties in FED (p<0.001) but not in BK (p = 0.67) or re-grafts (p = 0.067).

Conclusion

Endothelial diseases represented the top indication for keratoplasty over the 8-year period. PKP is still the most used technique in Catalonia, but endothelial keratoplasties and especially DMEK showed a significant increasing trend over the last years. This is congruent with the main rationale nowadays for keratoplasties: to customize and transplant as less tissue as possible. Therefore, the availability of precut tissue could have definitely enforced such approach.

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

PURPOSE

To describe a surgical technique for Descemet membrane endothelial keratoplasty (DMEK) using a pull-through, endothelium-in insertion device, the DMEK EndoGlide. We evaluated the endothelial cell loss (ECL) associated with the EndoGlide-DMEK (E-DMEK) technique in both ex vivo and prospective clinical studies.

METHODS

The ex vivo study involved calcein acetoxymethyl staining and preparation of DMEK grafts, which were trifolded endothelium-in, loaded into the EndoGlide, pulled through, and unfolded in imaging dishes. Inverted fluorescent microscopy was performed, and ECL was quantified using trainable segmentation software. The prospective clinical series describes the outcomes of consecutive surgeries using the E-DMEK technique. Grafts were pulled through the EndoGlide with forceps and unfolded in the anterior chamber endothelium-down. Our main outcome measure was ECL in both studies.

RESULTS

In the ex vivo study with 9 human donor corneas, mean ECL was 15.2% ± 5.4% (n = 9). In our clinical series of 69 eyes, leading indications for surgery were pseudophakic/aphakic bullous keratopathy (47.8%), previous failed grafts (23.2%), and Fuchs endothelial dystrophy (18.8%). Rebubbling and primary graft failure rates related to E-DMEK were 11.6% and 1.5%, respectively. Among eyes with at least 6 months of follow-up, mean preoperative endothelial cell density was 2772 (range 2457-3448) cells/mm, and postoperative endothelial cell density was 1830 (range 541-2545) cells/mm. Mean ECL was 33.6% (range 7.5-80.4; n = 32) at the 7.1 (range 6-11) months follow-up.

CONCLUSIONS

The ex vivo and pilot clinical studies suggest that E-DMEK shows acceptable rates of ECL, with safe and promising early clinical outcomes.

Graft detachments in endothelial keratoplasty

Graft detachment is the most common complication of endothelial keratoplasty. With the ongoing advancements in the field of endothelial keratoplasty, our understanding of risk factors of graft detachments and its management has been evolving. Various prevention measures have been described in literature including presoaking the donor graft, anterior chamber tamponade, venting incisions, sutures to prevent dislocation of graft. Management of a detached graft involves secondary interventions such as rebubbling, suturing and regrafts. In this review, we discuss graft detachment in different types of endothelial keratoplasty techniques including Descemet stripping endothelial keratoplasty, Descemet stripping automated endothelial keratoplasty and Descemet's membrane endothelial keratoplasty; with emphasis on incidence, risk factors, preventive measures and their management.

Endothelial keratoplasty with anterior chamber intraocular lens versus secondary posterior chamber intraocular lens

AIM

To describe the long-term outcomes of Descemet stripping automated endothelial keratoplasty (DSAEK) with an anterior chamber intraocular lens (ACIOL) compared to secondary posterior chamber (PC) IOL.

METHODS

This was a retrospective comparative cohort study. The clinical data of 82 eyes from 82 consecutive patients with pseudophakic (PBK) or aphakic bullous keratopathy (ABK) who either underwent DSAEK with retained or secondary ACIOL (n=23) or DSAEK with IOL exchange and/or secondary PCIOL (retropupillary iris-claw IOL, n=25; intrascleral-fixated IOL, n=29; or sulcus IOL, n=5) were analysed. The main outcome measures were graft survival and complications up to 5 years.

RESULTS

The graft survival in the secondary PCIOL group was superior than the ACIOL group over 5 years (year 1, 100.0% vs 100.0%; year 3, 94.7% vs 75.0%; year 5, 91.1% vs 60.6%, p=0.022). The presence of an ACIOL was a significant risk factor associated with graft failure (HR, 4.801; 95% CI, 1.406 to 16.396, p=0.012) compared to a secondary PCIOL. There was no significant difference in the rate of graft detachment and elevated intraocular pressure between the groups. There were five cases (9.3%) of IOL subluxation or dislocation in the retropupillary iris-claw and intrascleral-fixated IOL groups.

CONCLUSIONS

Eyes that underwent DSAEK with ACIOL in situ had poorer long-term graft survival compared with those with secondary PCIOL. Intraocular lens exchange was not associated with a higher complication rate. In ABK or PBK eyes with ACIOL, we recommend performing IOL exchange and/or secondary PCIOL implantation combined with endothelial keratoplasty.

Corneal transplantation after failed grafts: Options and outcomes

Corneal transplantation is the most commonly performed human tissue transplantation procedure worldwide. Because of the large number of transplants, corneal graft failure has become one of the most common indications for corneal transplantation. The relatively recently developed lamellar transplant techniques have brought about specific potential complications leading to graft failure that may require different approaches to repeat transplantation other than penetrating keratoplasty. On the other hand, these new lamellar techniques also provide novel ways of rescuing failed penetrating grafts, with potential advantages over successive penetrating keratoplasties, such as reduced intraoperative risks and faster visual rehabilitation. We summarize the incidence and risk factors of graft failure for penetrating and lamellar (stromal and endothelial) corneal transplants and discuss the various surgical alternatives currently available to rescue such failed grafts, with a focus on the reported outcomes and limitations.

Repeat keratoplasty in failed Descemet stripping automated endothelial keratoplasty

Purpose:

To evaluate the clinical factors associated with repeat Descemet stripping automated endothelial keratoplasty (DSAEK) or penetrating keratoplasty (PKP) in cases of failed DSAEK.

Methods:

Retrospective observational study of cases with failed DSAEK admitted to our center for a repeat keratoplasty over 5 years (January 2013–Decemeber 2017) was undertaken. Demographic and perioperative details of all cases and type of repeat keratoplasty were recorded. Logistic regression analysis was performed to analyze the factors affecting the type of repeat keratoplasty.

Results:

A total of 94 eyes with failed DSAEK were evaluated. Repeat DSAEK was performed in 66% and PKP in 34% of cases. Significantly increased odds for requiring PKP were observed in association with stromal scarring [odds ratio (OR) = 2.9, P = 0.018)], trainee surgeons (OR = 4.05, P = 0.008), intraoperative complications (OR = 4.58, P = 0.003), scleral fixated intraocular lens or anterior chamber intraocular lens in situ (OR = 33.8, P < 0.001), secondary glaucoma (OR = 3.02, P = 0.015), peripheral anterior synechiae (OR = 8.6, P < 0.001), preoperative corneal thickness (OR = 1.01, P < 0001), time to primary surgery (OR = 1.03, P = 0.03), post-DSAEK host thickness (OR = 1.01, P < 0.001), and time interval from graft failure to regraft (OR = 1.18, P < 0.001). All eyes with congenital hereditary endothelial dystrophy, bee-sting-induced corneal decompensation, Axenfeld-Rieger syndrome, and multiple failed grafts underwent secondary PKP. All cases (nine eyes) that required surgical intervention for secondary glaucoma underwent secondary PKP (P < 0.001).

Conclusion:

Repeat DSAEK is feasible in up to two-third of cases of failed DSAEK. A PKP is required in one-third of cases, and various preoperative, intraoperative and postoperative factors are associated with unsuitability for repeat DSAEK.

Complications and outcomes of descemet stripping automated endothelial keratoplasty with artisan aphakia intraocular lens implantation

AIM

To evaluate the complications and outcomes of descemet stripping automated endothelial keratoplasty (DSAEK) combined with artisan aphakia intraocular lens (IOL) implantation in severely damaged eyes without capsular support.

METHODS

DSAEK combined with artisan iris claw IOL implantation was performed on 29 eyes. All eyes were of abnormal structure due to complications from prior intraocular surgeries and ocular trauma. Ocular complications observed included graft dislocations, high intraocular pressure (IOP), IOL dislocations, macular edema and hyphema. Best corrected visual acuity (BCVA), IOP and mean central endothelial cell density (ECD) were recorded.

RESULTS

Thirteen eyes had a history of ocular trauma, 10 eyes had an anterior chamber IOL, 16 eyes had prior vitrectomy. The iris was abnormal in 22 cases. Graft dislocation occurred in 5 (17.2%) of 29 eyes. IOL dislocation occurred in 2 eyes (6.9%). High IOP was found in 9 eyes and was controlled with treatment. The preoperative mean BCVA was 20/286. The 6mo postoperative mean BCVA was 20/42. The average center ECD was 1965.3 cells/mm² at 6mo, and the rate of the donor cell loss was 34.7%.

CONCLUSION

DSAEK combined with artisan aphakia IOL implantation is an alternative option for resolving endothelial and lens disorders in aphakic eyes without capsular support. However, it should be performed cautiously for eyes with severe iris defects.

Endothelial keratoplasty in eyes with a retained angle-supported intraocular lens

PURPOSE

To describe the outcomes of endothelial keratoplasty (EK) for bullous keratopathy in eyes with a retained angle-supported anterior chamber intraocular lens (acIOL).

METHODS

Among 263 consecutive EK procedures, 7 DMEK and 11 DSAEK procedures were identified in eyes with an acIOL and included in the present retrospective case series. Pre- and postoperative status including ocular history, anatomical outcome and complications as well as best-corrected visual acuity was evaluated.

RESULTS

Ocular history included complicated cataract surgery (n = 11), ocular trauma (n = 4) and primary intracapsular cataract extraction (n = 3). Surgery-related complications included primary graft failure (n = 1), graft detachment (n = 1), endophthalmitis (n = 1) and allograft rejection (n = 1). A clear cornea at the final examination (14 ± 4 months) was observed in 14/18 (78%), while the visual outcome was limited due to significant ocular comorbidity in 9 out of 14 uncomplicated procedures.

CONCLUSION

The presented short-term outcomes suggest that both DMEK and DSAEK are feasible in eyes with an angle-supported acIOL yielding an acceptable graft survival rate in the first postoperative year.

Long-term Visual Outcomes Comparing Descemet Stripping Automated Endothelial Keratoplasty and Penetrating Keratoplasty

PURPOSE

To compare 5-year visual acuity and refraction outcome in Descemet stripping automated endothelial keratoplasty (DSAEK) and penetrating keratoplasty (PK) for Fuchs endothelial dystrophy (FED) or bullous keratopathy (BK) in Asian eyes.

DESIGN

Prospective interventional case series.

METHODS

We analyzed 828 consecutive cases of DSAEK (423) or PK (405) for FED and BK from the Singapore Cornea Transplant Registry performed from 1991 to 2011. Our main outcome measures were best spectacle-corrected visual acuity (BSCVA) with astigmatism (cylinder) and spherical equivalent (SE) over 5 years of follow-up.

RESULTS

Mean age was 67.5 ± 11.5 years (50.1% male, 49.9% female) and majority was Chinese (76.6%, n = 634) in our multiracial Asian population. DSAEK eyes had significantly better BSCVA (P < .001-.037) with lower SE (P < .001-.017) and cylinder (P < .001), independent of surgical indication, compared to PK over 5 years. DSAEK was superior to PK over 5 years (P < .001-.026) in FED, but only over 3 years in BK (P < .001-.031). DSAEK in FED eyes had significantly better BSCVA compared to BK eyes (P = .006 at 4-year follow-up). DSAEKs with preoperative BSCVA < 1.3 logMAR had significantly better visual outcomes than cases with ≥ 1.3 logMAR (P < .001-.042). PKs had significantly higher postoperative refractive correction than DSAEKs, with no significant influence of the surgery indication.

CONCLUSIONS

In our study cohort, DSAEK provided significantly better long-term BSCVA and lower astigmatism than PK over 5 years of follow-up. Visual outcomes of DSAEK for FED were better than BK. In some analyses for years 1-3, analysis of covariance adjustment indicated that this DSAEK-associated better long-term BSCVA was independent of better preoperative vision in DSAEK eyes.

Factors Associated With Graft Detachment After Primary Descemet Stripping Automated Endothelial Keratoplasty

PURPOSE

To identify risk factors associated with postoperative graft detachment after Descemet stripping automated endothelial keratoplasty (DSAEK).

METHODS

In this retrospective institutional cohort study, the study group included all consecutive eyes that underwent primary DSAEK between January 2005 and October 2015 at Villa Serena-Villa Igea private hospitals (Forlì, Italy) and developed postoperative graft detachment (n = 45). The control group included all eyes that underwent primary DSAEK during the same period and did not develop graft detachment (n = 1167). The main outcome measure was whether or not postoperative graft detachment occurred.

RESULTS

Main indications for surgery included Fuchs endothelial dystrophy (525/1212 = 41%), pseudophakic bullous keratopathy (422/1212 = 35%), and a failed penetrating keratoplasty (PK) graft (190/1212 = 16%). Postoperative graft detachment occurred in 45 of 1212 (3.7%) eyes. Medically treated glaucoma, previous trabeculectomy, previous aqueous shunt procedure, and failed PK were all associated with an increased risk for graft detachment in univariate analysis. No particular lens status at the time of graft implantation was significantly associated with graft detachment, including the presence of an anterior chamber intraocular lens [odds ratio (OR), 1.5; 95% confidence interval (CI), 0.35-6.46, P = 0.58] or aphakia at the time of graft transplantation (OR, 1.37; 95% CI, 0.41-4.57, P = 0.74). Cataract removal during surgery was not associated with an increased risk for detachment (OR, 0.77; 95% CI, 0.39-1.5, P = 0.47). Previous trabeculectomy (OR, 4.21; 95% CI, 1.53-11.56, P = 0.005) and a previous failed PK graft (OR, 3.04; 95% CI, 1.6-5.78, P = 0.001) were the only independent risk factors for graft detachment in multivariate analyses.

CONCLUSIONS

Previous PK and trabeculectomy are independent risk factors for postoperative graft detachment in primary DSAEK.

Five-Year Graft Survival Comparing Descemet Stripping Automated Endothelial Keratoplasty and Penetrating Keratoplasty

PURPOSE

To compare 5-year graft survival after Descemet stripping automated endothelial keratoplasty (DSAEK) and penetrating keratoplasty (PK) in Asian eyes.

DESIGN

Prospective, nested, cohort study.

PARTICIPANTS

Consecutive patients who underwent DSAEK (423 eyes) or PK (405 eyes) for Fuchs' endothelial dystrophy (FED) or bullous keratopathy (BK).

METHODS

Clinical data and donor and recipient characteristics were recorded from our prospective cohort from the Singapore Corneal Transplant Registry. All surgeries were performed by the corneal surgeons at our center, which included cases performed or partially performed by corneal fellows in training under direct supervision.

MAIN OUTCOME MEASURES

Five-year cumulative graft survival.

RESULTS

Overall mean age was 67.8±9.8 years, and 50.1% of patients were men. There were no significant differences in age (P = 0.261) or gender (P = 0.78) between PK and DSAEK groups in our predominantly Chinese (76.6%) Asian cohort, with more BK compared with FED (68.1% vs. 31.9%; P < 0.001). Overall 5-year graft survival was superior for DSAEK compared with PK (79.4% vs. 66.5%; P < 0.001, log-rank test). Median 5-year percent endothelial cell density loss was significantly greater in PK compared with DSAEK (60.9% vs. 48.7%; P = 0.007). Cox regression analysis revealed that BK was a significant factor associated with graft failure (hazard ratio [HR], 3.30; 95% confidence interval [CI], 2.05-5.33; P < 0.001), and PK was more likely to fail compared with endothelial keratoplasty (HR, 1.61; 95% CI, 1.08-2.41; P = 0.02) adjusting for confounders such as recipient age, gender, and donor factors. Five-year cumulative incidence of complications such as graft rejection (P < 0.001), epitheliopathy (P < 0.001), suture-related corneal infections (P < 0.001), and wound dehiscence (P = 0.002) were greater in the PK group compared with the DSAEK group.

CONCLUSIONS

In Asian eyes from the same study cohort with standardized surgical and postoperative regimes, 5-year graft survival was superior for DSAEK compared with PK in eyes with FED and BK.

Comparison of ACIOL Retention With IOL Exchange in Patients Undergoing Descemet Stripping Automated Endothelial Keratoplasty

PURPOSE

To investigate clinical outcomes in the management of anterior chamber intraocular lenses (ACIOLs) in patients requiring Descemet stripping automated endothelial keratoplasty (DSAEK) for pseudophakic corneal edema.

METHODS

This is a retrospective review of DSAEK procedures performed at a single center between May 1, 2006, and August 1, 2014.

RESULTS

Forty-three eyes (41 patients) with pseudophakic corneal edema and an ACIOL were identified. In 26 eyes (60.5%), the ACIOL was retained [intraocular lens retention (IOLR) group], and in 17 eyes (39.5%), intraocular lens exchange [(IOLX) group] was concurrent with DSAEK. No significant difference was noted between the IOLR and IOLX groups for the following: the incidence of primary graft failure (7.7% vs. 5.9%; P = 1.0); the incidence (3.8% vs. 0.0%; P = 1.0) or rate (0.036 per eye-year vs. 0 per eye-year; P = 0.28) of secondary graft failure; or the incidence (7.7% vs. 11.8%; P = 1.0) or rate (0.056 per eye-year vs. 0.073 per eye-year; P = 0.69) of endothelial rejection. However, the incidence (23.1% vs. 58.8%; P = 0.026) and rate (0.291 per eye-year vs. 0.475 per eye-year; P = 0.033) of increased intraocular pressure were significantly higher in the IOLX group. There were more complications in the IOLX group, although the difference was not significant (7.7% vs. 29.4%; P = 0.093).

CONCLUSIONS

There is no significant difference in the incidence of primary graft failure or in the rate of secondary graft failure or endothelial rejection in eyes with ACIOL retention or exchange. However, as IOLX is associated with intraoperative and postoperative complications and an increased rate of postoperative intraocular pressure elevation, we recommend performing DSAEK with retention of well-positioned ACIOLs in these eyes.

Descemet membrane endothelial keratoplasty

Descemet membrane endothelial keratoplasty (DMEK) allows for selective replacement of damaged endothelial cells, using only donor Descemet's membrane with endothelium. However, early adoption by corneal surgeons has been limited (illustrated by graft registry reports: 0.7% all corneal transplants in the USA; 0.4% in Australia for 2011) due to challenges in donor preparation and surgical technique. Recently, innovative donor preparation techniques may improve availability of pre-stripped DMEK donors from eye banks. The refinement of donor insertion and manipulation techniques has also improved outcomes and reduced graft detachment rates-still, the most common postoperative complication following DMEK. Randomised studies are needed to compare clinical practices and surgeon preferences, such as intraoperative use of long-acting gas, early versus late intervention of graft detachments and postoperative steroid management. A review of current literature reveals that most publications to date are reports from similar study cohorts by surgeons who pioneered and advocate this technique. Thus, more long-term clinical studies in other tertiary centres are required in order to confirm if the purported advantages of DMEK such as improved visual outcomes and reduced graft rejection are replicable among most corneal surgeons.