Impact of 68Ga-PSMA PET/CT on radiation treatment planning of prostate cancer patients.

AIM: This study aimed to assess the impact of 68Ga-PSMA PET/CT on radiation treatment (RT) planning in prostate cancer patients with salvage (sRT) or definitive (dRT) radiotherapy. METHODS: 38 patients (27 sRT, median PSA 0.79 ng/ml (range 0.06-12.1); 11 dRT, median PSA 4.35 ng/ml (range 1.55-55.5) underwent 68Ga-PSMA PET/CT before RT. Influence of 68Ga-PSMA PET/CT on the extent of planning target volume (PTV) and addition of PET-based boosts were assessed. Median follow up was 12 months (range 3-24). RESULTS: 68Ga-PSMA PET/CT showed positive findings in 23/38 patients (8/23: local recurrence (LR), 11/23: nodal metastasis, 1/23: LR and nodal, 2/23: solitary bone metastasis, 1/23: oligometastatic nodal/ bone metastases). In sRT primary PTV was changed in 16/27 patients extending the PTV to the lymphatic drainage (10/16), PSMA-positive LR (3/16), bone metastases (2/16) and both nodal/bone metastases (1/16). PET-based increase of primary PTV was 116%. PET-based boosts were administered in 19/27 patients (8/19: local, 10/19: nodal, 1/19: both), median boost volume was 31.3 cm3 (range 17.2-80.2) (local) and 19.7 cm3 (range 3.0-109.3) (nodal). PTV was changed in 1/11 (9%) of dRT patients (extension of primary PTV to the lymphatic drainage (RT volume of 644.5 cm3), additional nodal boost (volume of 2.7 cm3, 23.1 Gy)). All patients showed biochemical response (mean PSA decrease 88.8 +/- 14.0%). Nadir PSA was reached 10 months (range 1-17) after end of RT (median 0.07 ng/ml, range 0.002-3.96). Within a median 12 months follow-up (range 3-22/8-24 in sRT/dRT), median PSA was 0.05 ng/ml (range 0.002-8.5) (sRT) and 0.26 ng/ml (range 0.02-2.68) (dRT). CONCLUSIONS: 68Ga-PSMA PET/CT influenced sRT planning in almost 63% and dRT in 9% of patients by change of PTV and additional boosts.

Combined Osteopontin Blockade and Type 2 Classical Dendritic Cell Vaccination as Effective Synergetic Therapy for Conjunctival Melanoma.

Angiogenesis and immune protection are essential at the onset of tumorigenesis. Angiogenesis serves to nourish the tumor, and prevention of immune defenses, for example, by dendritic cells (DCs), allows tumor growth. In this study, we investigated whether there are factors with dual functions that are both angiogenic and immunomodulatory and represent a therapeutic target. We analyzed 1) innate immune responses intratumorally and in draining lymph nodes and 2) angiogenic factors in conjunctival melanoma (CM), a potentially lethal malignant tumor at the ocular surface whose immune and vascular responses are largely unknown. For this purpose, an HGF-Cdk4R24C model in immunocompetent C57BL/6 mice was used and revealed that CD103- type 2 classical DC (cDC2s) were the most abundant DC subtype in healthy conjunctiva, whereas in CM, CD103- cDC2s, CD103+ type 1 cDCs, monocyte-derived DCs, and plasmacytoid DCs were significantly increased. In our analysis of angiogenic factors in CM, the examination of 53 angiogenesis-related factors that might interact with DCs identified osteopontin (OPN) as a major tumor-derived protein that interacts with DCs. Consistent with these findings, 3) a dual therapeutic strategy that inhibited tumor cell function by an OPN blocking Ab while enhancing the immune response by cDC2 vaccination resulted in 35% failure of tumor development. Moreover, tumor progression, monocyte-derived DC infiltration, and intratumoral angiogenesis were significantly reduced, whereas survival and CD8+ T cell infiltration were increased in treated mice compared with the control group. Therefore, we identified OPN blockade in combination with cDC2 vaccination as a potential future therapeutic intervention for early stages of CM by combining antiangiogenic and host immune stimulating effects.

Radiosensitizing Effects of Irinotecan versus Oxaliplatin Alone and in Combination with 5-Fluorouracil on Human Colorectal Cancer Cells.

To date, oxaliplatin and irinotecan are used in combination with 5-flourouracil (5-FU) for metastatic colorectal cancer. In this study it was tested whether oxaliplatin and irinotecan and their combinations with 5-FU have an enhanced effect when treated simultaneously with ionizing radiation. In addition, it should be compared whether one combination therapy is more effective than the other. Colorectal cancer cells (HT-29) were treated with irinotecan or oxaliplatin, both alone and in combination with 5-FU, and subsequently irradiated. The cell growth, metabolic activity and proliferation of cells were investigated, and the clonogenic survival was determined. Furthermore, the assessment of radiation-induced DNA damage and the influence of the drugs and their combinations on DNA damage repair was investigated. Treatment with irinotecan or oxaliplatin in combination with 5-FU inhibited proliferation and metabolic activity as well as clonogenic survival and the DNA damage repair capacity of the tumor cells. The comparison of oxaliplatin and irinotecan with simultaneous irradiation showed the same effect of both drugs. When oxaliplatin or irinotecan was combined with 5-FU, tumor cell survival was significantly lower than with monotherapy; however, there was no superiority of either combination regimen. Our results have shown that the combination of 5-FU and irinotecan is as effective as the combination of 5-FU with oxaliplatin. Therefore, our data support the use of FOLFIRI as a radiosensitizer.

The impact of palliative radiotherapy on health-related quality of life in patients with head and neck cancer - Results of a multicenter prospective cohort study.

Purpose: Palliative radiotherapy for patients with head and neck cancer can be used to alleviate symptoms. Only a few studies have investigated its impact on patient-reported outcomes (PRO). Therefore, we conducted a prospective multicenter observational study. The primary objective was to assess changes in health-related quality of life (HrQoL) per PRO. Methods: Eligibility criteria included i.) head and neck cancer and ii.) palliative radiotherapy indicated (EQD2Gy < 60 Gy). The primary follow-up date was eight weeks after radiotherapy (t8w). PRO measures included the EORTC QLQ-C30 and EORTC QLQ-H&N43 and pain per Numeric Rating Scale (NRS). Per protocol, five PRO domains were to be reported in detail as well as PRO domains corresponding to a primary and secondary symptom as determined by the individual patient. We defined a minimal important difference (MID) of 10 points. Results: From 06/2020 to 06/2022, 61 patients were screened and 21 patients were included. Due to death or decline in health-status, HrQoL data was available for 18 patients at the first fraction and for eight patients at t8w. The MID was not met for the predefined domains in terms of mean values as compared from first fraction to t8w. Individually in those patients with available HrQoL data at t8w, 71% (5/7) improved in their primary and 40% (2/5) in their secondary symptom domain reaching the MID from first fraction to t8w, respectively. There was a significant improvement in pain per NRS in those patients with available data at t8w per Wilcoxon signed rank test (p = 0.041). Acute mucositis of grade ≥3 per CTCAE v5.0 occurred in 44% (8/18) of the patients. The median overall survival was 11 months. Conclusion: Despite low patient numbers and risk of selection bias, our study shows some evidence of a benefit from palliative radiotherapy for head and neck cancer as measured by PRO.German Clinical Trial Registry identifier: DRKS00021197.

The novel role of lymphatic vessels in the pathogenesis of ocular diseases.

Historically, the eye has been considered as an organ free of lymphatic vessels. In recent years, however, it became evident, that lymphatic vessels or lymphatic-like vessels contribute to several ocular pathologies at various peri- and intraocular locations. The aim of this review is to outline the pathogenetic role of ocular lymphatics, the respective molecular mechanisms and to discuss current and future therapeutic options based thereon. We will give an overview on the vascular anatomy of the healthy ocular surface and the molecular mechanisms contributing to corneal (lymph)angiogenic privilege. In addition, we present (i) current insights into the cellular and molecular mechanisms occurring during pathological neovascularization of the cornea triggered e.g. by inflammation or trauma, (ii) the role of lymphatic vessels in different ocular surface pathologies such as dry eye disease, corneal graft rejection, ocular graft versus host disease, allergy, and pterygium, (iii) the involvement of lymphatic vessels in ocular tumors and metastasis, and (iv) the novel role of the lymphatic-like structure of Schlemm's canal in glaucoma. Identification of the underlying molecular mechanisms and of novel modulators of lymphangiogenesis will contribute to the development of new therapeutic targets for the treatment of ocular diseases associated with pathological lymphangiogenesis in the future. The preclinical data presented here outline novel therapeutic concepts for promoting transplant survival, inhibiting metastasis of ocular tumors, reducing inflammation of the ocular surface, and treating glaucoma. Initial data from clinical trials suggest first success of novel treatment strategies to promote transplant survival based on pretransplant corneal lymphangioregression.

Cystathionine ß-synthase as novel endogenous regulator of lymphangiogenesis via modulating VEGF receptor 2 and 3.

Lymphangiogenesis is a key player in several diseases such as tumor metastasis, obesity, and graft rejection. Endogenous regulation of lymphangiogenesis is only partly understood. Here we use the normally avascular cornea as a model to identify endogenous regulators of lymphangiogenesis. Quantitative trait locus analysis of a large low-lymphangiogenic BALB/cN x high-lymphangiogenic C57BL/6 N intercross and prioritization by whole-transcriptome sequencing identify a novel gene responsible for differences in lymphatic vessel architecture on chromosome 17, the cystathionine ß-synthase (Cbs). Inhibition of CBS in lymphatic endothelial cells results in reduce proliferation, migration, altered tube-formation, and decrease expression of vascular endothelial growth factor (VEGF) receptor 2 (VEGF-R2) and VEGF-R3, but not their ligands VEGF-C and VEGF-D. Also in vivo inflammation-induced lymphangiogenesis is significantly reduce in C57BL/6 N mice after pharmacological inhibition of CBS. The results confirm CBS as a novel endogenous regulator of lymphangiogenesis acting via VEGF receptor 2 and 3-regulation and open new treatment avenues in diseases associated with pathologic lymphangiogenesis.

New Therapeutic Approaches for Conjunctival Melanoma-What We Know So Far and Where Therapy Is Potentially Heading: Focus on Lymphatic Vessels and Dendritic Cells.

Conjunctival melanoma (CM) accounts for 5% of all ocular melanomas and arises from malignantly transformed melanocytes in the conjunctival epithelium. Current therapies using surgical excision in combination with chemo- or cryotherapy still have high rates for recurrences and metastatic disease. Lately, novel signal transduction-targeted and immune checkpoint inhibitors like cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) inhibitors, programmed cell death protein-1 (PD-1) receptor inhibitors, BRAF- or MEK-inhibitors for systemic treatment of melanoma have improved the outcome even for unresectable cutaneous melanoma, improving patient survival dramatically. The use of these therapies is now also recommended for CM; however, the immunological background of CM is barely known, underlining the need for research to better understand the immunological basics when treating CM patients with immunomodulatory therapies. Immune checkpoint inhibitors activate tumor defense by interrupting inhibitory interactions between tumor cells and T lymphocytes at the so-called checkpoints. The tumor cells exploit these inhibitory targets on T-cells that are usually used by dendritic cells (DCs). DCs are antigen-presenting cells at the forefront of immune response induction. They contribute to immune tolerance and immune defense but in the case of tumor development, immune tolerance is often prevalent. Enhancing the immune response via DCs, interfering with the lymphatic pathways during immune cell migration and tumor development and specifically targeting tumor cells is a major therapeutic opportunity for many tumor entities including CM. This review summarizes the current knowledge on the function of lymphatic vessels in tumor growth and immune cell transport and continues to compare DC subsets in CM with related melanomas, such as cutaneous melanoma and mucosal melanoma.

Pre-incubation of corneal donor tissue with sCD83 improves graft survival via the induction of alternatively activated macrophages and tolerogenic dendritic cells.

Immune responses reflect a complex interplay of cellular and extracellular components which define the microenvironment of a tissue. Therefore, factors that locally influence the microenvironment and re-establish tolerance might be beneficial to mitigate immune-mediated reactions, including the rejection of a transplant. In this study, we demonstrate that pre-incubation of donor tissue with the immune modulator soluble CD83 (sCD83) significantly improves graft survival using a high-risk corneal transplantation model. The induction of tolerogenic mechanisms in graft recipients was achieved by a significant upregulation of Tgfb, Foxp3, Il27, and Il10 in the transplant and an increase of regulatory dendritic cells (DCs), macrophages (Mφ), and T cells (Tregs) in eye-draining lymph nodes. The presence of sCD83 during in vitro DC and Mφ generation directed these cells toward a tolerogenic phenotype leading to reduced proliferation-stimulating activity in MLRs. Mechanistically, sCD83 induced a tolerogenic Mφ and DC phenotype, which favors Treg induction and significantly increased transplant survival after adoptive cell transfer. Conclusively, pre-incubation of corneal grafts with sCD83 significantly prolongs graft survival by modulating recipient Mφ and DCs toward tolerance and thereby establishing a tolerogenic microenvironment. This functional strategy of donor graft pre-treatment paves the way for new therapeutic options in the field of transplantation.

Preincubation of donor tissue with a VEGF cytokine trap promotes subsequent high-risk corneal transplant survival.

AIMS: Pathological neovascularisation of the host bed and the transplant itself is the main risk factor for graft rejection after corneal transplantation. This study aims to prevent this process by preincubation of the corneal donor tissue ex vivo with an antivascular endothelial growth factor (VEGF) cytokine trap blocking additional postsurgical hemangiogenesis and lymphangiogenesis to promote high-risk graft survival. METHODS: The donor tissue was preincubated with a VEGFR1R2 cytokine trap for 24 hours prior to murine high-risk corneal transplantation (human IgG Fc was used as the control). The distribution of VEGFR1R2 Trap in the cornea was investigated by immunohistochemistry. Corneas were excised to quantify the blood vessels (BVs) and lymphatic vessels (LVs) and draining lymph nodes (dLNs) were harvested to analyse the phenotype of dendritic cells (DCs) and T cells at week 1, 2 and 8 post-transplantation. Graft survival was compared between preincubation with VEGFR1R2 Trap and human IgG Fc in high-risk recipients. RESULTS: VEGFR1R2 Trap was present in the graft for at least 2 weeks after surgery and additionally diffused into the corneal recipient. BVs, LVs and macrophages in the whole cornea were significantly decreased 1-week and 2-week post-transplantation (p<0.05). In dLNs the frequency of CD11c+DCs was significantly reduced, whereas CD200R+ regulatory DCs were significantly increased after keratoplasty (p<0.05). Furthermore, long-term high-risk graft survival was significantly improved (p<0.01). CONCLUSIONS: Preincubation of corneal donor tissue with a VEGFR1R2 cytokine trap can significantly promote subsequent high-risk corneal transplant survival and thereby opens new treatment avenues for high-risk corneal transplantation.

Lymphatic Trafficking in the Eye: Modulation of Lymphatic Trafficking to Promote Corneal Transplant Survival.

(Lymph)angiogenesis into the cornea prior to and after corneal transplantation is a critical risk factor for allograft rejection. Lymphatic vessels even more than blood vessels seem important in mediating immune responses, as they facilitate allograft sensitization in the draining lymph nodes. Thus, the concept of modulating lymphatic trafficking to promote corneal graft survival seems promising. A variety of approaches has been developed to inhibit progressive lymphangiogenesis in experimental settings. Recently, additionally to pharmacological approaches, clinically available techniques such as UVA-based corneal collagen crosslinking and fine needle diathermy were reported to be effective in regressing lymphatic vessels and to experimentally promote graft survival. Clinical pilot studies also suggest the efficacy of blocking antigen presenting cell trafficking to regional lymph nodes by regressing corneal lymphatic vessels to enhance allograft survival in high-risk eyes. In this article, we will give an overview of current strategies to modulate lymphatic trafficking with a special focus on recently reported strategies, which may be easy to translate into clinical practice. This novel concept of temporary, pretransplant regression of lymphatic vessels at the site of transplantation to promote subsequent corneal transplant survival ("lymphangioregressive preconditioning") may also be applicable to other transplantation sites later.

Macrophage-Mediated Tissue Vascularization: Similarities and Differences Between Cornea and Skin.

Macrophages are critical mediators of tissue vascularization both in health and disease. In multiple tissues, macrophages have been identified as important regulators of both blood and lymphatic vessel growth, specifically following tissue injury and in pathological inflammatory responses. In development, macrophages have also been implicated in limiting vascular growth. Hence, macrophages provide an important therapeutic target to modulate tissue vascularization in the clinic. However, the molecular mechanisms how macrophages mediate tissue vascularization are still not entirely resolved. Furthermore, mechanisms might also vary among different tissues. Here we review the role of macrophages in tissue vascularization with a focus on their role in blood and lymphatic vessel formation in the barrier tissues cornea and skin. Comparing mechanisms of macrophage-mediated hem- and lymphangiogenesis in the angiogenically privileged cornea and the physiologically vascularized skin provides an opportunity to highlight similarities but also tissue-specific differences, and to understand how macrophage-mediated hem- and lymphangiogenesis can be exploited for the treatment of disease, including corneal wound healing after injury, graft rejection after corneal transplantation or pathological vascularization of the skin.

Aggregated neutrophil extracellular traps occlude Meibomian glands during ocular surface inflammation.

PURPOSE: Obstructive Meibomian gland dysfunction (MGD) is one of the leading causes of evaporative dry eye disease. Meibomian glands at the eyelid secrete lipids that prevent evaporation of the aqueous tear film. The pathogenesis of obstructive MGD is incompletely understood to date. Herein, we aim to investigate the pathogenesis of obstructive MGD using murine and human samples with various forms of ocular surface inflammation. METHOD: The presence of Neutrophil extracellular Traps (NETs) was detected with immunofluorescence analysis of ocular surface discharge and biopsy samples from patients with blepharitis. Tear fluid from patients with MGD and blepharitis were evaluated for the presence of inflammatory mediators using bead based immunoassay. Murine model of allergic eye disease (AED) was performed to investigate the role of NETs in MG occlusion. RESULTS: we show that the ocular discharge from patients with blepharitis contains aggregated neutrophil extracellular traps (aggNETs). Furthermore, the ducts of human Meibomian glands affected by blepharitis were largely congested by aggNETs. Tear fluid from patients with MGD showed elevated neutrophil chemoattractants (C5a, IL6, IL8 and IL18). C5a and IL8 correlated with the degree of deficiency of tear fluid. In the murine model of allergic eye disease (AED), aggNETs accumulated in the MG leading to occlusion of their ducts and the retrograde pent-up of the fluid followed by acinar atrophy. Constraining aggNET formation by genetic or pharmacological inhibition of peptidyl arginine deiminase type 4 (PADI4) effectively reduced MG damage. CONCLUSION: We conclude that aggNETs occlude MG causing MGD after ocular surface inflammation.

Corneal Crosslinking to Regress Pathologic Corneal Neovascularization Before High-Risk Keratoplasty.

PURPOSE: Corneal neovascularization is the main risk factor for graft rejection after high-risk penetrating keratoplasty (PK). Corneal crosslinking (CXL) has been shown to regress pathological corneal blood and lymphatic vessels and to reduce the risk of graft rejection after high-risk PK experimentally in mice. The aim of this work was to analyze whether CXL is also able to regress corneal neovascularization in patients and is a safe procedure in the context of high-risk PK. METHODS: This retrospective case series included 5 patients with progressive corneal neovascularization and the need for high-risk PK because of graft rejection and/or keratitis that received CXL and PK between April 2019 and January 2020. CXL was performed before or in combination with PK and the effect of CXL on corneal neovascularization was assessed morphometrically on slit-lamp images. Patients were followed up to determine the incidence of adverse effects and graft rejection. RESULTS: In 1 case, peripheral corneal CXL was performed first as a single procedure, followed by an additional peripheral CXL procedure combined with PK. In all other cases, peripheral CXL was directly combined with PK. No intraoperative or postoperative complications were observed. Peripheral CXL resulted in a reduction of corneal neovascularization (mean reduction of 70.5% ± 22.7%). Revascularization was not observed. All transplants remained clear and without immune reactions (mean follow-up 16.4 ± 14.9 weeks, range 4-42 weeks). CONCLUSIONS: CXL is able to reduce pathological corneal neovascularization and might therefore be a novel treatment option to improve graft survival after high-risk PK.

New Technologies in Clinical Trials in Corneal Diseases and Limbal Stem Cell Deficiency: Review from the European Vision Institute Special Interest Focus Group Meeting.

To discuss and evaluate new technologies for a better diagnosis of corneal diseases and limbal stem cell deficiency, the outcomes of a consensus process within the European Vision Institute (and of a workshop at the University of Cologne) are outlined. Various technologies are presented and analyzed for their potential clinical use also in defining new end points in clinical trials. The disease areas which are discussed comprise dry eye and ocular surface inflammation, imaging, and corneal neovascularization and corneal grafting/stem cell and cell transplantation. The unmet needs in the abovementioned disease areas are discussed, and realistically achievable new technologies for better diagnosis and use in clinical trials are outlined. To sum up, it can be said that there are several new technologies that can improve current diagnostics in the field of ophthalmology in the near future and will have impact on clinical trial end point design.

VEGF TrapR1R2 Suspended in the Semifluorinated Alkane F6H8 Inhibits Inflammatory Corneal Hem- and Lymphangiogenesis.

Purpose: Semifluorinated alkanes (SFAs) are used at the ocular surface as lubricants or vehicles for drugs. The purpose of this study was to test the effect of vascular endothelial growth factor (VEGF) TrapR1R2 suspended in the SFA perfluorohexyloctane (Trap/F6H8) on corneal neovascularization. Methods: Suture placement was used to induce inflammatory corneal neovascularization in mice. Treatment groups were: Trap/F6H8, VEGF TrapR1R2 as aqueous formulation dissolved in phosphate buffer (Trap), F6H8, and phosphate buffer (controls). Eye drops were applied 3×/daily for 2 weeks. Afterward, corneas were stained with CD31 and LYVE-1 to analyze corneal hem- and lymphangiogenesis. To investigate the effect of on inflammatory cell recruitment, corneal CD45+ cells were quantified. In addition, epithelial wound closure after debridement was assessed by corneal fluorescein staining. Results: Trap/F6H8 was as effective as Trap in inhibiting corneal hemangiogenesis and lymphangiogenesis after 2 weeks of treatment. After 3 days of treatment, Trap/F6H8 was even more effective than Trap in inhibiting corneal hemangiogenesis. Both treatment groups (Trap/F6H8 and Trap) significantly reduced corneal CD45+ cell recruitment. Epithelial closure after debridement was unaffected by Trap/F6H8 or Trap. Conclusions: In this study, we demonstrate that F6H8 is a potential carrier for VEGF TrapR1R2 to topically treat corneal neovascularization. Our findings might open new treatment avenues for local anti-angiogenic therapy at the cornea, as F6H8 is already approved for the usage at the ocular surface. Translational Relevance: With this study we show for the first time that SFAs can serve as carriers for anti-angiogenic drugs at the ocular surface.

Supplemental Anti Vegf A-Therapy Prevents Rebound Neovascularisation After Fine Needle Diathermy Treatment to Regress Pathological Corneal (LYMPH)Angiogenesis.

Fine needle diathermy (FND) is an effective method to destroy and regress pathologic corneal blood and lymphatic vessels. However, it is unknown whether FND itself causes a rebound corneal neovascularisation and whether that can be prevented by VEGF blockade. In female BALB/c mice, the suture-induced inflammatory corneal neovascularisation model was used to induce hem- and lymphangiogenesis. Thereafter, prevascularized mice were divided into 2 groups: the combination therapy group received FND cauterization and subsequent VEGF TrapR1R2 eye drops three times per day whereas the monotherapy group was treated only with FND. Three, 7 and 14 days after the treatment, corneas were collected and stained with FITC-conjugated CD31 and LYVE-1 followed by Cy3-conjugated secondary antibody to quantify corneal blood and lymphatic vessels. Relative mRNA expression of VEGF in the cornea was quantified by using qPCR. FND cauterization as monotherapy significantly obliterated (lymph)angiogenesis at early time points; however, this treatment led to secondary corneal hem- and lymphangiogenesis associated with significant upregulation of pro(lymph)angiogenic VEGF-A, VEGF-C, VEGF-D and infiltration of macrophages. Combining FND cauterization with VEGF TrapR1R2 treatment prevented the undesired effect of the FND procedure alone and significantly better regressed corneal blood and lymphatic vessels at 1 week after the treatment compared to monotherapy and control group (p < 0.01).

Effect of Iris Color on the Outcome of Descemet Membrane Endothelial Keratoplasty.

PURPOSE: To explore the impact of iris color on the outcome of Descemet membrane endothelial keratoplasty (DMEK). METHODS: Consecutive cases of Fuchs endothelial dystrophy after DMEK were retrospectively analyzed from the prospective Cologne DMEK database between 2011 and 2017 at the University of Cologne, Germany. Iris pictures were graded by color into blue, green, or brown and compared regarding outcome parameters including best-corrected visual acuity (converted to logarithm of the minimal angle of resolution), central corneal thickness, endothelial cell density (ECD), each at preoperative (baseline) and postoperative 12 months, rebubbling rates, cystoid macular edema (CME), and immune rejections after surgery. RESULTS: One thousand one hundred six eyes of 814 patients were included in this study that consisted of 354 blue eyes, 418 green eyes, and 244 brown eyes. There was no significant correlation between iris color and any parameter (best corrected visual acuity; P = 0.064 at preoperatively, P = 0.959 at 12 months) (ECD; P = 0.158 preoperatively, P = 0.859 at 12 months) (central corneal thickness; P = 0.148 preoperatively, P = 0.252 at 12 months). The loss of ECD at 12 months after surgery was 37.2% ± 1.0% in blue eyes, 37.2% ± 0.9% in green eyes, and 37.2% ± 1.2% in brown eyes (P = 0.999). Immune rejections were 1.7%, 2.9%, and 0.8% (P = 0.168) in blue, green, and brown eyes, respectively. Rebubbling rates and CME incidence were similar in each group (P = 0.129, and P = 0.552 respectively). CONCLUSIONS: The iris color has no significant impact on the outcome after DMEK. Thus, DMEK can be applied effectively, regardless of the iris color.

Short- and Long-Term Results of Xenogeneic-Free Cultivated Autologous and Allogeneic Limbal Epithelial Stem Cell Transplantations.

PURPOSE: To evaluate the short- and long-term success rates of xenogeneic-free cultivated limbal epithelial stem cell transplantation (CLET) for the treatment of limbal stem cell deficiency (LSCD). METHODS: Thirteen patients with LSCD underwent an autologous (n = 9) or allogeneic (n = 4) CLET. The primary end point was to assess the long-term anatomical success rate of transplanted grafts at a follow-up of at least 3 years, in comparison with the short-term outcomes. Secondary end points involved reviewing functional improvement, patient-reported symptoms, and change in percentage area of corneal vascularization in both short-term and long-term. RESULTS: The mean short- and long-term follow-up periods were 2.1 ± 0.38 years and 6.7 ± 1.81 years, respectively. The total anatomical success rate was 46.1% in the short-term, but it decreased to 23.1% in the long-term. A partial success rate of 30.8% was observed in both short- and long-term, and the failure rate increased from 23.1% to 46.1%. The mean percentage of vessel area decreased from 12.11% ± 5.29% preoperatively to 7.82% ± 6.70% in the short-term and increased to 8.70% ± 6.32% in the long-term. There was a significant improvement in best-corrected visual acuity (P = 0.044) in the short-term although not in the long-term (P = 0.865). CONCLUSIONS: This study shows that anatomical and functional success rates of CLET decrease over time. We believe that the decline of success is related to the extent of disease, cell origin, and lack of niche protection because subtotal LSCD and autologous donor cells confer a higher chance of success in the long-term.