Corneal Graft Survival Rates Research Articles

Deep anterior lamellar keratoplasty and penetrating keratoplasty in macular corneal dystrophy: comparison of visual and topographic outcomes and complications.

This study aims to assess and compare the postoperative visual and topographic outcomes, complications, and graft survival rates following deep anterior lamellar keratoplasty and penetrating keratoplasty in patients with macular corneal dystrophy. In this study we enrolled 59 patients (23 male; and 36 female) with macular corneal dystrophy comprising 81 eyes. Out of these, 64 eyes underwent penetrating keratoplasty, while 17 eyes underwent deep anterior lamellar keratoplasty. The two groups were analyzed and compared based on best-corrected visual acuity, corneal tomography parameters, pachymetry, complication rates, and graft survival rates. After 12 months, 70.6% of the patients who underwent deep anterior lamellar keratoplasty (DALK) and 75% of those who had penetrating keratoplasty (PK) achieved a best-corrected visual acuity of 20/40 or better (p=0.712). Following surgery, DALK group showed lower front Kmean (p=0.037), and Q values (p<0.01) compared to the PK group. Postoperative interface opacity was observed in seven eyes (41.2%) in the DALK group. Other topography values and other complications (graft rejection, graft failure, cataract, glaucoma, microbial keratitis, optic atrophy) did not show significant differences between the two groups. The need for regrafting was 9.4% and 11.8% in the PK and DALK groups, respectively (p=0.769). Graft survival rates were 87.5% and 88.2% for PK and DALK; respectively (p=0.88 by Log-rank test). Both PK and DALK are equally effective in treating macular corneal dystrophy, showing similar visual, topographic, and survival outcomes. Although interface opacity occurs more frequently after DALK the visual results were comparable in both groups. Therefore, DALK emerges as a viable surgical choice for patients with macular corneal dystrophy without Descemet membrane involvement is absent.

Comparison of Five-Year Graft Survival After Keratoplasty in the Veteran Population

Purpose: We investigated the corneal graft survival rate after penetrating keratoplasty (PK) and Descemet stripping endothelial keratoplasty (DSEK) in a veteran population. Methods: A retrospective review was conducted on patients undergoing a primary PK or DSEK at a large Veterans Affairs Medical Center between January 2005 and August 2019. Exclusion criteria included patients with a postoperative follow-up less than 5 years and patients undergoing additional ocular procedures during surgery. Patients were classified into 3 groups depending on their glaucoma status before corneal transplant: no pre-existing glaucoma, medically managed glaucoma, or surgically managed glaucoma. Graft survival was calculated using the Kaplan–Meier survival analysis. Results: A total of 30 eyes underwent PK, and 28 eyes underwent DSEK. There was no significant difference in graft survival rates between PK and DSEK at 1 year (83% vs. 79%, P = 0.555), 3 years (53% vs. 64%, P = 0.536), and 5 years (40% vs. 54%, P = 0.399). When combining PK and DSEK groups, Kaplan–Meier analysis showed a highly significant difference in 5-year graft survival between patients without pre-existing glaucoma (58%) and patients with either medically (50%) or surgically managed glaucoma (0%). Conclusions: We find approximate parity in 1-year, 3-year, and 5-year survival rates after PK and DSEK within the veteran population. However, survival rates for both procedures are lower than those previously reported within other populations. Additional studies to understand these differences in larger cohorts are warranted. Ophthalmologists must understand the increased risk of graft failure in the veteran population to provide appropriate counseling.

Destructive effects on endothelial cells of grafts in cytomegalovirus DNA-positive patients after keratoplasty.

To investigate corneal graft survival rate and endothelial cell density (ECD) loss after keratoplasty in cytomegalovirus (CMV) positive patients. This was a retrospective cohort study. We analyzed the clinical data of patients who underwent viral DNA detection in aqueous humor/corneal tissue collected during keratoplasty from March 2015 to December 2018 at the Peking University Third Hospital, Beijing, China. To further evaluate the effect of CMV on graft survival rate and ECD loss, patients were divided into three groups: 1) CMV DNA positive (CMV+) group; 2) viral DNA negative (virus-) group, comprising virus- group eyes pairwise matched to eyes in the CMV+ group according to ocular comorbidities; 3) control group, comprising virus- group eyes without ocular comorbidities. The follow-up indicators including graft survival rate, ECD, ECD loss, and central corneal thickness (CCT), were analyzed by Tukey honestly significant difference (HSD) test. Each group included 29 cases. The graft survival rate in CMV+ group were lowest among the three groups (P=0.000). No significant difference in donor graft ECD was found among three groups (P=0.54). ECD in the CMV+ group was lower than the virus- group at 12 (P=0.009), and 24mo (P=0.002) after keratoplasties. Furthermore, ECD loss was higher in the CMV+ group than in the virus- group in the middle stage (6-12mo) post-keratoplasty (P=0.017), and significantly higher in the early stage (0-6mo) in the virus- group than in the control group (P=0.000). CMV reduces the graft survival rate and exerts persistent detrimental effects on the ECD after keratoplasty. The graft ECD loss associate with CMV infection mainly occurrs in the middle stage (6-12mo postoperatively), while ocular comorbidities mainly affects ECD in the early stage (0-6mo postoperatively).

Survival Outcome and Prognostic Factors of Corneal Transplantation: A 15-Year Retrospective Cohort Study at King Chulalongkorn Memorial Hospital.

PurposeTo evaluate long-term survival outcomes and determine the prognostic factors of corneal transplantation performed at a tertiary referral hospital in Thailand.DesignA 15-year retrospective cohort study.Materials and MethodsOne corneal graft per patient was selected; graft failure was defined as graft opacity due to recurrent disease or endothelial cell dysfunction. Kaplan–Meier survival analysis was performed. Median time to failure was compared using the Log rank test. Prognostic factors were identified using the Cox proportional hazards model.ResultsWe enrolled 704 transplanted grafts. Surgical indications were optical (88.5%), therapeutic (10.2%), and tectonic (1.3%). The most common diagnoses were corneal opacity (25.3%), bullous keratopathy (15.8%), and regraft (14.8%). The overall survival rates at 1, 3, 5, and 10 years were 87.5%, 72.0%, 59.2%, and 41.7%, respectively. Univariate analysis identified age, primary diagnosis, graft size, pre-existing glaucoma, prior lens status, prior intraocular surgery, indication for surgery, donor endothelial cell density, and previous graft rejection as prognostic factors for graft failure. Multivariate analysis revealed three prognostic factors: primary diagnosis of perforation/peripheral ulceration/Mooren’s ulcer (hazard ratio [HR]=28.57; 95% confidence interval [CI], 6.32–129.16; P<0.001), active keratitis (HR=24.30; 95% CI, 5.88–100.43; P<0.001), regraft (HR=9.37; 95% CI, 2.27–38.66; P=0.002), and pseudophakic/aphakic bullous keratopathy (HR=7.97; 95% CI, 1.93–32.87; P=0.004); pre-existing glaucoma (HR=1.52; 95% CI, 1.13–2.04; P=0.006); and previous graft rejection (HR=1.95; 95% CI, 1.54–2.48; P<0.001).ConclusionOverall corneal graft survival rate was high in the first postoperative year and decreased after that. Primary diagnosis, pre-existing glaucoma, and previous graft rejection negatively influenced graft survival.

Long-Term Review of Penetrating Keratoplasty: A 20-Year Review in Asian Eyes

To review the long-term outcomes of optical, therapeutic and tectonic forms of penetrating keratoplasty over a 20-year period in Asian eyes. Prospective cohort study involving the Singapore Corneal Transplant Study (SCTS). All penetrating keratoplasties (PK) performed at the Singapore National Eye Centre (SNEC) from January 1991 to December 2010 were analyzed using records from the computerized database of the SCTS. This database includes preoperative, intraoperative, and postoperative patient data and donor cornea data. Only primary grafts were included. Patient demographics, donor cornea source, indications for grafting, complications, graft survival rate, and causes of graft failure were analyzed. A total of 1,206 primary PKs were performed. The mean age of the patients was 55 years (range: <1-101 years). The overall corneal graft survival rates at 1, 5, 10, 15, and 20 years were 91%, 66.8%, 55.4%, 52%, and 44%, respectively. For optical grafts, pseudophakic bullous keratopathy, postinfectious corneal scarring and thinning and keratoconus were the most common diagnoses. Graft survival for optical grafts was significantly better than therapeutic and tectonic grafts at all time points. Multivariate analysis suggested that a younger donor cornea age and higher donor endothelial cell count are associated with better long-term graft survival for optical grafts. Irreversible allograft rejection and late endothelial failure accounted for more than 60% of graft failures. Graft survival decreased over time from 91% at 1 year to 44% at 20 years' follow-up. Allograft rejection and late endothelial failure accounted for more than 60% of graft failures.

Clinical Outcomes of Penetrating Keratoplasty and Descemet Stripping Automated Endothelial Keratoplasty in Asian Population with American Corneas.

To determine the comparative efficacy and safety of penetrating keratoplasty (PK) and Descemet stripping automated endothelial keratoplasty (DSAEK) in the Asian population receiving imported donor corneas, our single-center retrospective study provides analysis supporting the transition from PK to DSAEK in the Asian population using imported American donor corneas. We analyzed 259 patients with 241 and 57 cases of PK and DSAEK respectively during 2008 to 2017 using imported corneas at Chang Gung Memorial Hospital, Linkou, Taiwan. In terms of long-term graft survival analysis, there was no difference between PK and DSAEK (log-rank p = 0.386, HR = 0.920, 95% CI: [0.641–1.380]). However, Cox proportional regression analysis revealed that corneal survival rate of DSAEK group in the first 100 days after transplantation was inferior than that of PK group (log-rank p < 0.001, HR = 2.733, 95% CI: [1.501–4.977])]. Despite the inferior survival rate, there were significantly less neovascularization and Descemet membrane folds in the DSAEK group. Importantly, the non-complication rate of DSAEK was much higher than that of PK with significant difference (PK, 25.7% vs. DSAEK 42.0%, p = 0.022). Collectively, DSAEK is suggested as an alternative surgical modality in Asian patients using imported American donor corneas because of less complication, and no difference in long-term corneal graft survival rates between PK and DSAEK.

Graft Survival after Penetrating Keratoplasty in Cases of Trabeculectomy versus Ahmed Valve Implant.

Purpose To compare the corneal graft survival rates after penetrating keratoplasty (PKP) in cases of post-PKP glaucoma managed by either trabeculectomy with mitomycin C or Ahmed glaucoma valve (AGV). Methods This study was a retrospective interventional comparative study that included 40 eyes of 40 patients. The included patients had undergone previous PKP for anterior segment reconstruction after microbial or fungal keratitis, chemical burns, trauma, or perforated corneal ulcer. Post-PKP glaucoma was managed surgically by either trabeculectomy with mitomycin C (group 1) or Ahmed glaucoma valve (group 2). Results The first group (n=20) had undergone trabeculectomy with MMC, and the second group (n=20) had undergone AGV implantation. Regarding BCVA, there was no statistically significant difference between the 2 groups. Mean IOP was significantly lower in the AGV group at 6 months, 12 months, and 24 months (p=0.001). Mean IOP at 24 months dropped significantly from preglaucoma surgery levels in both groups (p=0.001). Rejection episodes occurred in 2 eyes (10%) of the trabeculectomy group versus 8 eyes (40%) in the AGV group (p=0.028). In the trabeculectomy group, corneal graft failure occurred in 1 (5%), 3 (15%), and 6 (30%) eyes at 6 months, 12 months, and 24 months, respectively. In the AGV group, corneal graft failure occurred in 2 (10%), 5 (25%), and 10 (50%) eyes at 6 months, 12 months, and 24 months, respectively. The mean time to failure in the trabeculectomy group was 12.33 ± 5.60 months versus 11.90 ± 5.70 months in the AGV group (p=0.027). Conclusion Managing postpenetrating keratoplasty glaucoma could be bothersome especially in complex cases. Ahmed glaucoma valve implant controls the intraocular pressure more effectively than trabeculectomy with mitomycin C. However, Ahmed glaucoma valve can result in higher rates of corneal graft failure in a shorter duration of time. This trial is registered with PACTR201712002861391 on 21 Dec 2017.

Outcomes of Trabeculectomy and Glaucoma Drainage Devices for Elevated Intraocular Pressure After Penetrating Keratoplasty.

To assess and compare the outcomes of trabeculectomy with and without antimetabolites (AMs) and glaucoma drainage devices (GDDs) in the management of elevated intraocular pressure (IOP) after penetrating keratoplasty (PK). Data of 84 eyes of 81 patients who underwent trabeculectomy (12 eyes without an AM and 42 eyes with an AM) or GDD implantation (30 eyes) after PK were reviewed retrospectively. The main outcome measures were IOP control, corneal graft survival, and postoperative ocular complications. At the final visit, IOP success (<22 mm Hg) was 58.3% in trabeculectomy alone, 64.3% in trabeculectomy with an AM (TrabAM), and 86.7% in GDD groups (P = 0.047). The median time from surgery to IOP failure was 1 month after trabeculectomy alone, 13 months after TrabAM, and 20 months after GDD implantation (P = 0.042). The cumulative probability of IOP success rates at 1 and 3 years postoperatively was as follows: 66.7% and 57.1% in trabeculectomy alone, 80.6% and 64.8% in TrabAM, and 92.3% and 84.6 in GDD groups (P = 0.063). The cumulative probability of corneal graft survival rates at 1 and 3 years postoperatively was as follows: 70.0% and 60.0% in trabeculectomy alone, 76.7% and 67.7% in TrabAM, and 65.8% and 52.6% in GDD groups (P = 0.549). GDDs are more successful than trabeculectomy in controlling IOP in eyes that have undergone PK, but they tend to have low corneal graft survival rates. Trabeculectomy without an AM has limited success and may be considered in a limited number of patients with a low risk for bleb failure.

Pars Plana-Modified versus Conventional Ahmed Glaucoma Valve in Patients Undergoing Penetrating Keratoplasty: A Prospective Comparative Randomized Study

ABSTRACTPurpose: To compare the outcome of pars-plana-modified Ahmed glaucoma valve (AGV) versus limbal-based conventional AGV into the anterior chamber, in patients undergoing penetrating keratoplasty (PK) for glaucoma with coexisting corneal diseases.Method: In this prospective randomized clinical trial, 58 eyes of 58 patients with glaucoma and coexisting corneal disease were divided into two groups. Group 1 (29 eyes of 29 patients) included patients undergoing limbal-based conventional AGV into the anterior chamber (AC) along-with PK and group 2 (29 eyes of 29 patients) included those undergoing pars-plana-modified AGV along-with PK. Outcome measures included corneal graft clarity, intraocular pressure (IOP), number of antiglaucoma medications, and postoperative complications. Patients were followed up for a minimum period of 2 years.Results: Out of 58 eyes (58 patients), 50 eyes (50 patients: 25 eyes of 25 patients each in group 1 and group 2) completed the study and were analyzed. Complete success rate for AGV (group 1: 76%; group 2: 72%; p = 0.842) and corneal graft clarity (group 1: 68%; group 2: 76%; p = 0.081) were comparable between the two groups at 2 years. Graft failure was more in conventional AGV (32%) as compared to pars plana-modified AGV (24%) but not statistically significant (p = 0.078) at 2 years.Conclusion: Though both procedures were comparable in various outcome measures, pars-plana-modified AGV is a viable option for patients undergoing PK, as it provides a relatively better corneal graft survival rate and lesser complications that were associated with conventional AGV.

Comparison of primary graft survival following penetrating keratoplasty and Descemet's stripping endothelial keratoplasty in eyes with prior trabeculectomy

PurposeTo compare corneal graft survival rate after primary Descemet's stripping endothelial keratoplasty (DSEK) and primary penetrating keratoplasty (PK) in patients with prior trabeculectomy or medically managed glaucoma.MethodsA retrospective chart review...

Three-year corneal graft survival rate in high-risk cases treated with subconjunctival and topical bevacizumab.

To evaluate the effect of combined subconjunctival and topical bevacizumab treatment on corneal graft survival rate in high-risk eyes. Prospective, consecutive, interventional case series. Fifty eyes of 50 high-risk patients scheduled for penetrating keratoplasty (PK) were included in the study; two Stevens-Johnson syndromes (SJS), five corneal combustions due to chemical burn, seven post-traumatic vascularised leucomas, 11 post-infectious vascularised leucomas, 19 rejected grafts and six corneal ulcers. Additional surgeries such as autologous limbal stem cell and/or amniotic membrane transplantation were performed together with PK in ten cases. All eyes received subconjunctival injection of 0.5ml bevacizumab (25mg/ml) after PK. Eyes with more than two quadrants of neovascularisation (NV) received bevacizumab drops (25mg/ml) postoperatively for up to 12weeks. Donor grafts were followed up for best-corrected visual acuity, graft clarity, change in NV, endothelial cell density loss (ECD), and adverse events. Mean follow-up was 36.5months (range 32-61). Best-corrected visual acuity increase was statistically significant in 82% (41/50) of eyes 3years after PK (paired t-test, p = 0.02). Thirty-five (70%) high-risk grafts remained clear throughout the 3-year follow-up period. Decrease of corneal NV was observed in 84% (42/50) of eyes treated with bevacizumab. ECD changed from preoperative 2,864 ± 301 down to 1,905 ± 187 cells/mm(2) at 3 postoperative years. A non-healing epithelial defect was recorded in one patient with SJS after 12weeks of topical bevacizumab. Combined subconjunctival and topical bevacizumab treatment may improve corneal graft survival rate in the majority of high-risk cases.

Five-year Outcomes of Eyes With Glaucoma Drainage Device and Penetrating Keratoplasty

To investigate intraocular pressure (IOP) control and corneal graft survival rates in eyes with glaucoma drainage device (GDD) implantation and penetrating keratoplasty (PK) and 5 years of follow-up data. Retrospective review. We performed a review of records of all patients who underwent both GDD placement and PK at our institution between January 1, 1988 and December 31, 2003. Twenty-eight eyes of 27 patients were studied. Glaucoma outcome was assessed by postoperative IOP, number of glaucoma medications, and need for further glaucoma surgery. Corneal grafts were assessed for clarity. All eyes had GDD placement in the anterior chamber. The mean pre-GDD IOP was 28.8 ± 10.3 mm Hg on a mean of 2.6 ± 0.8 glaucoma medications. At 5-year follow-up, the mean IOP was 13.0 ± 5.9 mm Hg on a mean of 0.9 ± 1.0 glaucoma medications. GDD implantation successfully controlled glaucoma in 96%, 86%, 79%, 75%, and 71% of eyes at 1, 2, 3, 4, and 5 years, respectively. Grafts remained clear in 96%, 82%, 75%, 57%, and 54% of eyes at 1, 2, 3, 4, and 5 years, respectively. Failure of glaucoma outcome or graft survival was associated with prior intraocular surgeries. Our data suggests that GDD placement can provide glaucoma control in a high percentage (71%) of eyes with PK even at 5 years. Furthermore, the success of PK in eyes with GDD remains reasonable (54%) at 5 years. IOP control and graft survival rates are comparable with earlier published studies with shorter follow-up or tube placement in the vitreous cavity.

Use of bevacizumab (anti‐VEGF treatment) in high‐risk corneal grafts

AbstractPurpose We evaluated the effect of bevacizumab treatment in a prospective 2 year follow‐up study of 50 [bdquo]high risk“ eyes undergoing penetrating keratoplasty (PKP).Methods Hihg‐risk diseases were: 2 Stevens Johnson syndrome (SJS), 6 chemical burns, 9 post‐herpetic, 16 other vascularized scars, 13 rejected grafts and 4 ulcers. PKP was performed in all 50 patients; combined with other procedures as follows: 12 “triple” procedures (PKP + cataract),11 PKP+ amniotic membrane transplantation (AMT),4 triple+AMT+ transplantation of limbal cells (LCAT). Subconjunctival injection of 25 mg/ml of bevacizumab was given to all patients at the end of surgery. Recipient corneal buttons were dissected into 3 corneal layers, stored in media for 24 hours at 37oC, and frozen till detection of VEGF quantity by immunoassay (ELISA). Corneal buttons from patients with non‐inflammatory diseases served as controls.Results Decrease of corneal neovascularization was observed in 88% of patients who received bevacizumab, and 86% of grafts remained clear. Mean best corrected visual acuity had statistically significant increase in all groups from 0.03 to 0.5, with the poorest visual outcome in SJS patients. Average postoperative astigmatism was ‐4,83 Dcyl. Average endothelial cell loss was 22.83% after one, and 31.97% after two years (similar in all groups). Secreted VEGF was significantly higher in high risk cases (2436.7 pg/ml) as compared to non‐inflamed corneas (504.7 pg/ml).Conclusion Combined “anti‐inflammatory“approach of AMT, LCAT and bevacizumab may significantly improve corneal graft survival rate in [bdquo]high‐risk“ eyes.

Long-Term Graft Survival in Deep Anterior Lamellar Keratoplasty

To determine corneal graft survival rates up to 10 years in a large consecutive series of deep anterior lamellar keratoplasties (DALKs). A retrospective, consecutive, noncomparative cases series of DALK procedures in a total of 806 eyes of 711 patients with stromal diseases and healthy endothelium performed between 2000 and 2009. Inclusion criterion was surgery performed by a single surgeon (660 eyes), with at least 6 months of follow-up. Graft survival was analyzed using the Kaplan-Meier method. Endothelial loss was analyzed with the Gaussian distribution and the χ methods. Follow-up time, and preoperative and postoperative endothelial cell density (ECD) were considered in the analyses. Six hundred sixty eyes of 502 patients met the entry criteria. Mean length of follow-up was 4.5 years (range, 0.5-10 years). We report an average graft survival rate of 99.3% (range, 98.5%-100%); 3 eyes (0.45%) experienced graft failure and 1 eye (0.15%) developed late endothelial failure because of an intraoperative complication. Predominant indications for DALK in this series were keratoconus (74%), postherpetic keratitis scarring (15%), and corneal stromal opacities of different etiology (11%). Endothelial loss from preoperative levels averaged 11% (range, 10%-13%) at 6 months through 10 years after DALK. ECD was unchanged between 6 months postoperatively and the last follow-up visits. DALK is a successful form of transplantation in stromal corneal disorders with healthy endothelium, with higher long-term graft survival rates and stable ECD 6 months postoperatively. DALK survival rates do not vary significantly over time.

High-Risk Eyes: Can We Increase Corneal Graft Survival Rate?

High-Risk Eyes: Can We Increase Corneal Graft Survival Rate?

Validation of tissue quality parameters for donor corneas, designated for emergency cases: corneal graft survival

To validate tissue quality parameters for donor corneas designated for emergency grafting for corneal graft survival. In a longitudinal cohort follow-up study, 131 emergency penetrating grafts were studied. Grafts were performed with a pool of organ-cultured donor corneas designated for emergency grafting and prepared for immediate use with all safety tests performed. Assignation criteria were: corneas with a small superficial stromal opacity but meeting all selection criteria for PKP tissue and corneas without stromal opacity, but an endothelial cell density from 1800 to 2300 cells/mm(2) or mild polymegathism or pleomorphism. Cox multivariate regression analysis, Kaplan-Meier survival and log rank test were applied. Of the 131 keratoplasties, 115 could be followed. One eye was lost during surgery because of an expulsive bleeding. In 15 cases, a conjunctival transplantation finished off the penetrating graft. Corneal graft survival was not significantly related to the presence of PKP quality of the donor endothelium, neither with a cloudy graft nor with endothelial decompensation as the cause of failure. Main risk factors for a failed graft were vascularization of the host cornea (p=0.0001), the presence of a systemic auto immune disease in the recipient (p=0.003) and the disease leading to the (imminent) perforation and emergency graft (p=0.021). A selected pool of donor corneas designated for emergency grafting that does not interfere with the scheduled procedures allows more efficient and safe use of donor tissue in case of a(n) (imminent) perforation. Corneal graft survival rates justify the criteria for selection.

Bedeutung der Cyclosporin-A-Absorption für eine effektive immunmodulatorische Therapie nach Hochrisikokeratoplastik

Cyclosporin A (CsA) is applied as an immune modulator in transplantation medicine, including high-risk keratoplasty. We examined the C(0) and C(2)-CsA serum levels after high-risk keratoplasty. The rate of so-called low absorbers was determined, and the importance of low absorption for the survival and rejection freedom of corneal grafts was examined. Follow-up of 89 high-risk cornea grafts in the patient group (n=32) ranged from 1 to 72 months postoperatively. The evaluation included data about serum levels of CsA C(0) (24 h after oral CsA application) and C(2) (2 h after oral CsA application) and clinical follow-ups. Using statistical methods, CsA C(0) and C(2) levels and clinical data were examined. Low absorbers did not reach the target C(2) levels by CsA dose adjustment. High intraindividual and interindividual variance of CsA C(0) and C(2) values was observed in the examined group of patients. A rate of up to 34.4% (n=11) represented the low absorbers. There was no significance of the low-absorption factor for clear graft survival, rejection freedom, or the rate of side effects observed. An acute endothelial rejection was observed in 23% of grafts and caused 37% of graft failures. In the patients without rheumatic corneal ulcers (n=27), 89% of the corneal grafts remained clear after 12 months, and 52% remained clear after 36 months. In our study, with a low number of patients and multiple cofactors, the influence of low-absorption CsA on the clear corneal graft survival and rejection rates could not be proved statistically. Due to the specific immune status of the cornea, the influence of low absorption may be lower than in organs such as the kidney and liver. In our study, the C(2) serum level of CsA after high-risk keratoplasty did not provide any helpful information about the prognosis of the corneal grafts or CsA treatment monitoring.

Risk factors for various causes of failure in initial corneal grafts.

To determine the risk factors for specific causes of initial corneal graft failure. This study analyzed corneal graft survival rates in a longitudinal noncomparative case series of 3992 consecutive penetrating keratoplasties performed at a single large referral center. Regrafts (n = 352) were excluded from the analysis of risk factors for initial graft failure. Data were collected retrospectively from August 1, 1982, through December 31, 1986, and prospectively from January 1, 1987, through August 31, 1996. Patients were examined preoperatively, at 1, 3, 6, 9, 12, 18, and 24 months posttransplantation, and annually thereafter. Potential risk factors were evaluated individually by Kaplan-Meier survival analysis. Cox proportional hazards regression modeling was then used to investigate the impact of each independent variable, adjusted for the confounding influence of the other independent variables. The use of topical glaucoma medications was a significant risk factor for corneal graft failure by 3 major causes: rejection, endothelial decompensation without a documented immunologic reaction, and ocular surface disease. Deep stromal vascularization was an independent risk factor for rejection failure. Diabetes mellitus, peripheral anterior synechiae, recipient race, and small trephination size were significant risk factors for endothelial failure. Independent risk factors differentially impact specific causes of corneal graft failure.

Corneal graft survival and intraocular pressure control after penetrating keratoplasty and glaucoma drainage device implantation

Objective To investigate corneal graft survival rates and intraocular pressure (IOP) control in eyes after penetrating keratoplasty (PK) and glaucoma drainage device (GDD) implantation. Design Retrospective, comparative, consecutive case series. Participants All patients who underwent PK and GDD implantation at the Bascom Palmer Eye Institute between January 1, 1993 and October 31, 1998. Main outcome measures Graft clarity and IOP control. Results Of the 72 eyes in 72 patients identified, 47 (65%) underwent combined PK and GDD implantation, and 25 (35%) underwent GDD placement after PK (2–30 months after PK; median, 13 months). The GDD type was Baerveldt 350 mm 2 in 57 eyes, Ahmed in 9, Krupin in 2, and other in 4 eyes. The GDD was placed in the anterior chamber in 54 eyes (75%) and in the vitreous cavity in 18 eyes (25%). Preoperative IOP was 11 to 53 mmHg with or without antiglaucoma medications in 16 eyes (30%) with the GDD implanted in the anterior chamber and in 4 eyes (22%) with the GDD placed in the vitreous cavity ( P = 0.76). At 1 year after GDD implantation, the graft was clear in 26 eyes (48%) with the GDD in the anterior chamber compared with 15 eyes (83%) with the GDD in the vitreous cavity ( P = 0.013). Forty-eight eyes (89%) with the GDD in the anterior chamber and 18 eyes (100%) with the GDD in the vitreous cavity had IOP between 5 and 21 mmHg with or without antiglaucoma medications ( P = 0.33). The mean reduction in IOP, 1 year after surgery, was 12 mmHg among eyes with the GDD in the anterior chamber, compared with 17 mmHg among eyes with the GDD in the vitreous cavity ( P = 0.13) Conclusions Corneal graft survival at 1 year is significantly higher among eyes with the GDD implanted in the vitreous cavity compared with those in which the GDD is implanted in the anterior chamber. The IOP was significantly lower at 1 year after surgery compared with before surgery in both groups, and there was no significant difference between the groups in IOP control and amount of IOP reduction. There was no significant difference in corneal graft survival or IOP control between eyes with the GDD implanted concurrently with the PK versus after the PK.

Corneal Graft Outcome Study

To determine overall 2- and 5-year corneal graft survival rates and to identify risk factors for corneal graft failure in our patient population. A retrospective chart review of 696 patients undergoing corneal transplantation performed by a single surgeon at The Toronto Western Hospital over a 7.5-year period. A total of 468 eyes met the inclusion criteria for this study. Overall, the 2- and 5-year graft survival rates were 78.8% and 64.5%, respectively. In a univariate analysis, patient age, gender, history of glaucoma, preoperative diagnosis, type of operative procedure, and postoperative factors all were shown to be significantly associated with graft survival. In a multivariate analysis, six independent predictors of graft failure were identified: preoperative diagnosis, neovascularization of the graft, the presence of peripheral anterior synechiae, gender, occurrence of one or more rejection episodes, and age of the recipient at the time of corneal transplantation. Risk of graft failure can vary substantially within a population of patients receiving a corneal transplant. The outcomes of this study concur with the risk factors for corneal graft failure in the literature and can be used as prognostic guidelines for both surgeons and patients.