Tacrolimus immunosuppression in high-risk corneal grafts

Treatment of Steroid-Resistant Nodular Episcleritis With Tacrolimus: A Case Report

A 46-year-old male, with no chronic medical illness, complained of pain, tearing, and redness for one-month duration, with no photophobia, discharge, or decrease in visual acuity. Examination revealed a small, painful, red swelling in the left sclera. Slit-lamp examination using a narrow bright slit beam revealed edema of the episcleral layer and injection of the superficial episcleral blood vessels. The rest of the anterior segment exam and fundoscopy were normal. The laboratory investigations and systemic workup were normal. The patient was initially treated with prednisolone acetate (Pred Forte) 1% every three hours per day for one week, and then four times per day for another week, and tapered gradually over eight weeks with systemic nonsteroidal anti-inflammatory drugs (NSAIDs) as diclofenac sodium for eight weeks with mild improvement of clinical symptoms, but the size of the lesion remained without any change and the patient started to have a relapse of symptoms at the end of the course. Topical tacrolimus drops of 0.1% concentration were prepared in the pharmacy under complete sterile precautions and were used four times per day for the following six weeks duration instead of the initial therapy (steroids and NSAIDs). Tacrolimus drops were then tapered gradually over another six weeks duration. The patient showed dramatic suppression of inflammation and exceptional remission of symptoms with complete resolution of the episcleritis. Topical tacrolimus is very effective in the treatment of nodular episcleritis, which is resistant to steroid therapy. Patients with nodular episcleritis suffer from prolonged bouts of inflammation that are characteristically more painful than the diffuse type and may be associated with other systemic diseases. The case is steroid-resistant nodular episcleritis, which did not respond to the usual treatment and showed a good response to treatment with tacrolimus, which was first introduced in episcleritis. Tacrolimus is being used in other ocular diseases, but its use in episcleritis is unique.

Management and prevention of corneal graft rejection

The management of an episode of corneal graft rejection (CGR) is primarily by corticosteroids. Immunomodulators are useful for long-term immunosuppression and in dealing with cases of high-risk (HR) corneal grafts. The classical signs of CGR following penetrating keratoplasty (PKP) include rejection line, anterior chamber (AC) reaction, and graft edema. However, these signs may be absent or subtle in cases of endothelial keratoplasty (EK). Prevention of an episode of graft rejection is of utmost importance as it can reduce the need for donor cornea significantly. In our previous article (IJO_2866_22), we had discussed about the immunopathogenesis of CGR. In this review article, we aim to discuss the various clinical aspects and management of CGR.

Why Are Corneal Specialists Resistant to Treating Patients Who Have Severe Ocular Surface Disease With Limbal Stem Cell Deficiency?

PURPOSE

To highlight the paucity of surgeons performing ocular surface stem cell transplantation with systemic immunosuppression (OSSTx with SI) for limbal stem cell deficiency (LSCD) patients, suboptimal treatments for LSCD, and obstacles to adoption.

METHODS

A review of the Eye Bank Association of America annual reports and the authors' case volume for OSSTx with SI was performed. Examination of the published literature on corneal surgeries, especially for LSCD, was completed. These findings were combined with our clinical observations to develop this editorial.

RESULTS

Despite techniques and protocols for OSSTx with SI published more than 30 years ago for the treatment of severe bilateral LSCD, only a small number of corneal specialists have adopted these techniques. There is a paucity of attention to this population of patients, with minimal publications to advance this area of our field. We are too often referred patients with LSCD and severe ocular surface disease that have had suboptimal treatments such as penetrating keratoplasties or primary keratoprostheses. Hesitancy for adopting OSSTx with SI is likely due to a lack of exposure to these procedures during training and fear of systemic immunosuppression. Corneal surgeons are likely unaware of the safety of systemic immunosuppression with appropriate monitoring especially when comanaging these patients with an organ transplant specialist.

CONCLUSION

There is a large unmet need for the treatment of corneal blindness secondary to conjunctival and LSCD. For the vast majority of patients, OSSTx should be the first surgical choice to treat these eyes. We hope major ophthalmology centers will meet this need by building programs, and groups of corneal surgeons should collaborate to create regional centers to make this treatment more accessible to help this population.

Management of limbal stem cell deficiency by amnion-assisted conjunctival epithelial redirection using vacuum-dried amniotic membrane and fibrin glue

PURPOSE

To study the outcome of a modified amnion-assisted conjunctival epithelial redirection (ACER) technique using vacuum-dried amnion (Omnigen) and fibrin glue for managing total limbal stem cell deficiency (LSCD).

METHOD

A retrospective, interventional case series of all patients with total LSCD who underwent limbal stem cell transplant (LSCT) using the modified ACER procedure between 2016 and 2019. The outcome was defined as: (1) success: complete corneal re-epithelialisation without conjunctivalisation; (2) partial success: sub-total corneal re-epithelialisation with partial non-progressive conjunctivalisation sparing the visual axis and (3) failure: conjunctivalisation affecting the visual axis.

RESULTS

Ten patients (six men), with a mean age of 46.2±18.4 years, were included. The mean follow-up was 23.0±13.9 months. Causes of LSCD were chemical eye injury (30%), congenital aniridia-related keratopathy (30%), ocular surface malignancy (20%), Steven-Johnson syndrome (10%) and contact lens overuse (10%). 50% were bilateral. The time from diagnosis to ACER (for acquired causes) was 45.6±44.4 months. 80% of patients achieved a complete/partial success following ACER and 20% of patients required repeat LSCT. Auto-LSCT was associated with a significantly higher chance of success than allo-LSCT (p=0.048). The mean best-corrected-visual-acuity (logMAR) improved significantly from 1.76±0.64 preoperatively to 0.94±0.94 at final follow-up (p=0.009). Omnigen was available off-the-shelf stored at room temperature and its transparency enabled visualisation of the healing epithelium beneath.

CONCLUSION

LSCT using the modified ACER serves as an effective ocular surface reconstruction technique in managing total LSCD and improving vision. Vacuum-dried amnion provides advantages of easy handling, transparency and storage at room temperature.

Outcomes following tacrolimus systemic immunosuppression for penetrating keratoplasty in infants and young children

OBJECTIVE

To report outcomes of tacrolimus immunosuppression after penetrating keratoplasty (PK) in very young children.

METHODS

Retrospective, consecutive, cohort study of children undergoing PK at a tertiary children's hospital between 2005 and 2016. Oral tacrolimus immunosuppression was given for 2 years, followed by topical tacrolimus.

RESULTS

Fourteen children (20 eyes) had 24 PKs; nineteen eyes had primary PKs, five eyes had repeat PKs. Mean age at primary graft was 95 days (3.1 months) for anterior segment dysgenesis (ASD), 430 days (14.3 months) for non-ASD children. Eleven children (15 eyes) had ASD. Three children (five eyes) had non-ASD: two children (three eyes) had glaucoma-related corneal opacity and one child (two eyes) had congenital hereditary endothelial dystrophy (CHED). One-year rejection-free survival rates following primary PK was 80% for ASD (n = 15) and 100% for non-ASD (n = 4). At final review, 5/15 of primary grafts for ASD were clear. 10/15 failed after a mean of 19 months, specifically attributable to infection (n = 2), rejection (n = 2) and glaucoma (n = 2). 4/4 primary non-ASD grafts are clear at final review (mean follow-up = 77 months). All repeat grafts (n = 5), failed after a mean of 38.25 months. Considering all grafts, 15/24 (62.5%) failed: 5/15 due to infection, 2/15 due to rejection, 8/15 due to glaucoma, phthisis, perforation or vascularised with no rejection. At last review (mean = 58.1 months, range 28-84), overall cohort survival is 37.5%. Final visual acuities range between 0.86 and 2.4 LogMAR.

CONCLUSION

We compare our results to published literature: 1-year graft survival was higher than previously reported, with lower failure due to rejection. Overall infection rates did not increase, however, proportionally, severe infections were higher. Overall graft survival is at least comparable to reported literature.

Update on Pediatric Corneal Diseases and Keratoplasty

Managing pediatric corneal disorders is challenging as the prognosis of pediatric keratoplasty depends on several factors. Advancements in the genetic basis of congenital corneal diseases and investigations in congenital corneal conditions provide a better understanding of pediatric corneal conditions. Surgeons performing keratoplasty in children now have a choice of various techniques. Evolving surgical techniques of anterior lamellar and endothelial keratoplasties has expanded the management interventions in these pediatric corneal morbidity conditions; however, considerable concerns still exist in association with corneal transplantation in infants and children. Outcomes in pediatric keratoplasty depend upon the preoperative indications, the timing of surgical intervention, intraoperative and postoperative factors including the patient/care givers' compliance. Factors such as low scleral rigidity, higher rate of graft failure, need for frequent examinations under anesthesia, and difficulty in optimal visual acuity assessment still remain a considerable challenge in pediatric scenarios. In children, deprivation amblyopia as a result of the corneal opacification can adversely affect visual development, causing dense amblyopia. Outcomes to surgical interventions for management of corneal opacification in children is further compromised by the pre-existing amblyopia apart from the concerns of refractive outcome of the graft. Graft rejection, graft infection, amblyopia, and glaucoma continue to be serious concerns. In recent years both anterior and posterior lamellar keratoplasty techniques are being increasingly performed in pediatric eyes, which offer advantages in the form of lower risk of graft rejection. The timing of surgery, careful case selection, cautious intraoperative approach, and optimal postoperative management can improve the anatomical and functional outcome in difficult cases.

Topical administration of tacrolimus and corticosteroids in tapering doses is effective in preventing immune rejection in high-risk keratoplasty: a 5-year follow-up study

Background

To evaluate the efficacy of the topical administration of immunosuppressants and corticosteroids in tapering doses in the management of patients with high-risk keratoplasty.

Methods

One hundred and six patients treated with topical immunosuppressants (50 eyes in the FK506 group and 56 eyes in the CsA group) and corticosteroid eye drops in tapering doses were enrolled in the study. The rates of rejection episodes, irreversible rejection, graft survival, and related influential factors were evaluated.

Results

The mean follow-up period was 48.1 ± 7.9 months (range, 36–60 months). The rates of rejection episodes and irreversible rejection were 14.0% and 6.00% in the FK506 group and 37.5% and 7.1% in the CsA group, respectively. Kaplan-Meier survival analysis demonstrated a significantly higher graft survival rate in the FK506 group (81.6%±5.3%, 71.1%±6.3%) compared with that in the CsA group (71.1%±6.3%, 57.5%±7.5%) at 3 and 5 years after surgery (P = 0.006). Multivariate logistic regression revealed that preoperative risk score ≥ 3 (P = 0.016) and endothelial immune rejection (P = 0.033) were risk factors associated with graft survival.

Conclusions

Topical administration of tacrolimus and corticosteroids in tapering doses is effective in decreasing the incidence of immune rejection in high-risk keratoplasty. Careful instruction of patients on the reasonable use of topical tacrolimus is critical to avoid immune rejection induced by sudden discontinuation of medication.

Bone Morphogenetic Protein 4 (BMP4) Enhances the Differentiation of Human Induced Pluripotent Stem Cells into Limbal Progenitor Cells

Corneal epithelium maintains visual acuity and is regenerated by the proliferation and differentiation of limbal progenitor cells. Transplantation of human limbal progenitor cells could restore the integrity and functionality of the corneal surface in patients with limbal stem cell deficiency. However, multiple protocols are employed to differentiate human induced pluripotent stem (iPS) cells into corneal epithelium or limbal progenitor cells. The aim of this study was to optimize a protocol that uses bone morphogenetic protein 4 (BMP4) and limbal cell-specific medium. Human dermal fibroblast-derived iPS cells were differentiated into limbal progenitor cells using limbal cell-specific (PI) medium and varying doses (1, 10, and 50 ng/mL) and durations (1, 3, and 10 days) of BMP4 treatment. Differentiated human iPS cells were analyzed by real-time polymerase chain reaction (RT-PCR), Western blotting, and immunocytochemical studies at 2 or 4 weeks after BMP4 treatment. Culturing human dermal fibroblast-derived iPS cells in limbal cell-specific medium and BMP4 gave rise to limbal progenitor and corneal epithelial-like cells. The optimal protocol of 10 ng/mL and three days of BMP4 treatment elicited significantly higher limbal progenitor marker (ABCG2, ∆Np63α) expression and less corneal epithelial cell marker (CK3, CK12) expression than the other combinations of BMP4 dose and duration. In conclusion, this study identified a successful reprogramming strategy to induce limbal progenitor cells from human iPS cells using limbal cell-specific medium and BMP4. Additionally, our experiments indicate that the optimal BMP4 dose and duration favor limbal progenitor cell differentiation over corneal epithelial cells and maintain the phenotype of limbal stem cells. These findings contribute to the development of therapies for limbal stem cell deficiency disorders.

Anti-Inflammatory Effect of Tacrolimus/Hydroxypropyl-β-Cyclodextrin Eye Drops in an Endotoxin-Induced Uveitis Model

Background: Uveitis is an infrequent disease which constitutes a major cause of ocular morbidity. Correct management is essential, being corticosteroids its cornerstone. In case of contraindication to corticosteroids or treatment failure, the use of topical tacrolimus (TAC) could be an alternative which has already demonstrated safety and effectiveness in other ocular pathologies. However, TAC eye drops are not marketed, thus their elaboration must be carried out in Hospital Pharmacy Departments (HPDs). Methods: 32 Sprague-Dawley rats were divided into 4 groups of 8 rats each: (a) untreated healthy rats (Healthy); (b) untreated Endotoxin-Induced Uveitis model-rats (EIU); (c) EIU-rats treated with standard treatment of dexamethasone ophthalmic drops (DXM) and (d) EIU-rats treated with TAC-hydroxypropyl-β-cyclodextrin eye drops previously developed by our group (TAC-HPβCD). The mRNA expression levels of IL-6, IL-8, MIP-1α and TNF-α, quantitative analysis of leucocytes in aqueous humor and histological evaluation were performed. Results: TAC-HPβCD eye drops demonstrated to reduce ocular inflammation, expression of IL-6, TNF-α, MIP-1α and leukocyte infiltration in aqueous humor. Conclusions: TAC-HPβCD eye drops showed beneficial effect in EIU model in rats, positioning as an alternative for uveitis treatment in case of corticosteroids resistance or intolerance.

Systemic Immunosuppression in Cornea and Ocular Surface Disorders: A Ready Reckoner for Ophthalmologists

Purpose: Many diseases of the cornea and ocular surface are manifestations of an underlying autoimmune process and require systemic immunosuppression for their management. These cases often present to a general ophthalmologist before being referred to an ocular immunologist or rheumatologist. However, the patients do need to be followed by the ophthalmologist to assess disease progression or for management of ocular co-morbidities and for taking care of ocular complications of the disease. Undeniably, there is a certain hesitance to promptly initiate them on systemic therapy because the literature regarding the indications, dosages, and side effects of this group of drugs is vast and dispersed.The aim of this review is to provide a source of ready reference for the general ophthalmologist as well as trainees and residents, on systemic immunosuppression for corneal and ocular surface disease. Methods: This review included 153 studies which were published as randomized controlled trials, systematic reviews, or as nonrandomized comparative studies (cohort or case-control series) on the topic of systemic immunosuppression in cornea and ocular surface disorders.Results: This review provides a concise summary of both the types of drugs and the common indications where they would be indicated, along with treatment and monitoring algorithms for each specific disease condition. The most used group of drugs are corticosteroids, which have significant side effects, particularly when administered systemically or for longer periods of time. To overcome this, steroid-sparing immunosuppressants are recommended. The four main classes of immunosuppressants used today are antimetabolites, T-cell inhibitors, alkylating agents and biologic agents. This review details the use of these drugs in ocular surface inflammation, including the dosing schedule, side effects and monitoring in allergic conjunctivitis, mucous membrane pemphigoid, peripheral ulcerative keratitis, immunological rejection against corneal allografts, anterior scleritis and aqueous deficiency dry eyes. Conclusions: This review provides an uncluttered and wholesome understanding of systemic immunosuppression in cornea and ocular surface diseases, with the hope that this will serve as a ready reckoner and help bridge the gap between ophthalmology and rheumatology for the betterment of our patients.

Development and Characterization of a Tacrolimus/Hydroxypropyl-β-Cyclodextrin Eye Drop

Uveitis is a vision inflammatory disorder with a high prevalence in developing countries. Currently, marketed treatments remain limited and reformulation is usually performed to obtain a tacrolimus eye drop as a therapeutic alternative in corticosteroid-refractory eye disease. The aim of this work was to develop a mucoadhesive, non-toxic and stable topical ophthalmic formulation that can be safely prepared in hospital pharmacy departments. Four different ophthalmic formulations were prepared based on the tacrolimus/hydroxypropyl-β-cyclodextrin (HPβCD) inclusion complexes’ formation. Phase solubility diagrams, Nuclear Magnetic Resonance (NMR) and molecular modeling studies showed the formation of 1:1 and 1:2 tacrolimus/HPβCD inclusion complexes, being possible to obtain a 0.02% (w/v) tacrolimus concentration by using 40% (w/v) HPβCD aqueous solutions. Formulations also showed good ophthalmic properties in terms of pH, osmolality and safety. Stability studies proved these formulations to be stable for at least 3 months in refrigeration. Ex vivo bioadhesion and in vivo ocular permanence showed good mucoadhesive properties with higher ocular permanence compared to the reference pharmacy compounding used in clinical settings (t_1/2 of 86.2 min for the eyedrop elaborated with 40% (w/v) HPβCD and Liquifilm^® versus 46.3 min for the reference formulation). Thus, these novel eye drops present high potential as a safe alternative for uveitis treatment, as well as a versatile composition to include new drugs intended for topical ophthalmic administration.

Corneal xenotransplantation: Where are we standing?

The search for alternatives to allotransplants is driven by the shortage of corneal donors and is demanding because of the limitations of the alternatives. Indeed, current progress in genetically engineered (GE) pigs, the introduction of gene-editing technology by clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9, and advanced immunosuppressants have made xenotransplantation a possible option for a human trial. Porcine corneal xenotransplantation is considered applicable because the eye is regarded as an immune-privileged site. Furthermore, recent non-human primate studies have shown long-term survival of porcine xenotransplants in keratoplasty. Herein, corneal immune privilege is briefly introduced, and xenogeneic reactions are compared with allogeneic reactions in corneal transplantation. This review describes the current knowledge on special issues of xenotransplantation, xenogeneic rejection mechanisms, current immunosuppressive regimens of corneal xenotransplantation, preclinical efficacy and safety data of corneal xenotransplantation, and updates of the regulatory framework to conduct a clinical trial on corneal xenotransplantation. We also discuss barriers that might prevent xenotransplantation from becoming common practice, such as ethical dilemmas, public concerns on xenotransplantation, and the possible risk of xenozoonosis. Given that the legal definition of decellularized porcine cornea (DPC) lies somewhere between a medical device and a xenotransplant, the preclinical efficacy and clinical trial data using DPC are included. The review finally provides perspectives on the current standpoint of corneal xenotransplantation in the fields of regenerative medicine.

Effects of VEGF Inhibitor Conbercept on Corneal Neovascularization Following Penetrating Keratoplasty in Rabbit Model

Purpose

To evaluate the effects of the vascular endothelial growth factor inhibitor conbercept (KH902) on corneal neovascularization and wound healing following penetrating keratoplasty in rabbits.

Methods

Conbercept was administered to New Zealand white rabbits through topical and subconjunctival routes. Corneal neovascularization and wound healing were examined by slit-lamp photography and histological analyses. The expressions of vascular endothelial growth factor inhibitor, α-smooth muscle actin, and keratocan in the corneal grafts were measured by real-time quantitative polymerase chain reaction (RT-qPCR).

Results

The anterior segment photographs demonstrated that corneal neovascularization started in the 2nd week. In the 4th week, histologically, the superficial corneal stroma layer showed disordered arrangement, and there were large numbers of dense inflammatory cells and blood vessels in the stroma layer. Vascular endothelial growth factor in the experimental groups was significantly decreased at all time points compared with the control group (both P = 0.001). Expression of α-smooth muscle actin in corneal grafts demonstrated an increase in time even it was lower in experimental groups, but the difference was not statistically significant (P equaled to 0.507 and 0.723, respectively). There were no significant differences with the expression of keratocan in all groups except that it significantly declined at the 4th week as to the second week in all groups and P values were 0.022, 0.020 and 0.014 in control (C), topical (E1), and subconjunctival (E2) group, respectively.

Conclusion

The study found that conbercept inhibited the formation of corneal neovascularization without affecting keratocan-mediated corneal wound healing and there were no significant differences between topical administration of different doses of conbercept on the rabbit corneal neovascularization after penetrating keratoplasty in this study.

Observation of topical tacrolimus on high-risk penetrating keratoplasty patients: a randomized clinical trial study

Background/Objectives

To evaluate the clinical efficacy of topical tacrolimus 0.1% and cyclosporine 1% on high-risk penetrating keratoplasty (PKP) patients.

Subjects/Methods

A series of 49 high-risk PKP patients (49 eyes), 20 males, 29 females from the age of 4 months to 74 years of age with the mean of 32.5 from 2012 to 2017 were recruited in this study. The patients were randomly divided into two groups by receiving either topical tacrolimus 0.1% or cyclosporine 1% respectively. Twenty five patients were treated with topical tacrolimus 0.1% and 24 patients with topical cyclosporine 1%. The traditional baseline management on these two groups were Tobramycin and Dexamethasone eye drops in the first 3 weeks and then tapered off. Clinical procedures and postoperative follow-up were documented.

Results

After 6–54 months follow-up, with the average of 24 months, 11 of 24 high-risk patients (11 eyes) had graft rejection, the rejection rate was 45.8% in topical cyclosporine 1% group. The rejections occurred from 35 days to 20 months after PKP. Three patients had irreversible rejection. On topical tacrolimus 0.1% group, the rejection occurred in four patients (four eyes) with rejection rate of 16%, and no irreversible rejection was observed. The graft rejection episodes were documented between 23 days and 24 months. As compared with the topical cyclosporine 1%, topical tacrolimus 0.1%, a key immunosuppressant, significantly decreased corneal graft rejection rate (p = 0.02).

Conclusions

Topical tacrolimus 01% on high-risk PKP patients significantly prevented corneal graft rejection, and it had less adverse effects and was very safe to high-risk patients as to topical cyclosporine 1%. Further case controlled randomized clinical trial studies are needed to establish the best management option for these high-risk patients.

Immune reactions after modern lamellar (DALK, DSAEK, DMEK) versus conventional penetrating corneal transplantation

In the past decade, novel lamellar keratoplasty techniques such as Deep Anterior Lamellar Keratoplasty (DALK) for anterior keratoplasty and Descemet stripping automated endothelial keratoplasty (DSAEK)/Descemet membrane endothelial keratoplasty (DMEK) for posterior keratoplasty have been developed. DALK eliminates the possibility of endothelial allograft rejection, which is the main reason for graft failure after penetrating keratoplasty (PK). Compared to PK, the risk of endothelial graft rejection is significantly reduced after DSAEK/DMEK. Thus, with modern lamellar techniques, the clinical problem of endothelial graft rejection seems to be nearly solved in the low-risk situation. However, even with lamellar grafts there are epithelial, subepithelial and stromal immune reactions in DALK and endothelial immune reactions in DSAEK/DMEK, and not all keratoplasties can be performed in a lamellar fashion. Therefore, endothelial graft rejection in PK is still highly relevant, especially in the "high-risk" setting, where the cornea's (lymph)angiogenic and immune privilege is lost due to severe inflammation and pathological neovascularization. For these eyes, currently available treatment options are still unsatisfactory. In this review, we will describe currently used keratoplasty techniques, namely PK, DALK, DSAEK, and DMEK. We will summarize their indications, provide surgical descriptions, and comment on their complications and outcomes. Furthermore, we will give an overview on corneal transplant immunology. A specific focus will be placed on endothelial graft rejection and we will report on its incidence, clinical presentation, and current/future treatment and prevention options. Finally, we will speculate how the field of keratoplasty and prevention of corneal allograft rejection will develop in the future.

Rhinosinusitis in Solid Organ Transplant Recipients: Analysis of 4562 Transplanted Patients

INTRODUCTION

Survival rates of solid organ transplant recipients are steadily increasing. Chronic immunosuppression is a key to sustain the transplanted organ. Thus, these patients are at a higher risk for fulminant disease and severe complications of rhinosinusitis (RS). Surprisingly, this has been scarcely discussed in the literature.

OBJECTIVE

To analyze the characteristics and disease course of RS in solid organ transplant recipients.

MATERIALS AND METHODS

Retrospective study. Medical records of all solid organ transplant recipients with a diagnosis RS treated at a national transplant center between the years 2001 and 2016 were reviewed.

RESULTS

Of 4562 solid organ transplant recipients, a documented diagnosis of RS was identified only in 61 (1.3%) patients. Sixty-four patients presented with posttransplantation RS; of them, 54.5% had chronic RS (CRS) and the remaining 45.5% patients were diagnosed with acute RS. Microbial cultures grew almost exclusively bacterial pathogens. A documented invasive fungal infection was noted in only 2 patients. A total of 24 (40%) patients underwent endoscopic sinus surgery, the majority (22) for CRS. On subgroup analysis, surgical intervention was more frequent in lung transplant recipients ( P = .005). Neither specific disease nor surgical complications were found.

CONCLUSIONS

Interestingly, acute fulminant infection or sinusitis complications in solid organ transplant patients were much lower than expected. CRS in this patient group was less frequent than expected as well. Whether chronic immunosuppression minimizes the likelihood for CRS deserves further investigation. A more surgically oriented approach in CRS patients may be favored early in the management course of medically refractory patients in light of patients excellent outcomes.

Current and emerging therapies for corneal neovascularization

The cornea is unique because of its complete avascularity. Corneal neovascularization (CNV) can result from a variety of etiologies including contact lens wear; corneal infections; and ocular surface diseases due to inflammation, chemical injury, and limbal stem cell deficiency. Management is focused primarily on the etiology and pathophysiology causing the CNV and involves medical and surgical options. Because inflammation is a key factor in the pathophysiology of CNV, corticosteroids and other anti-inflammatory medications remain the mainstay of treatment. Anti-VEGF therapies are gaining popularity to prevent CNV in a number of etiologies. Surgical options including vessel occlusion and ocular surface reconstruction are other options depending on etiology and response to medical therapy. Future therapies should provide more effective treatment options for the management of CNV.

Preclinical characterization and clinical evaluation of tacrolimus eye drops

Severe allergic ocular diseases as atopic keratoconjunctivitis can induce corneal damage due to inflammatory substances released from giant papillae. Tacrolimus eye drops are one of the current therapeutic alternatives for its treatment. This work is aimed at developing and characterizing a 0.03% tacrolimus ophthalmic formulation, which was introduced in three types of vehicles (BBS, PVA and Hyaluronic Acid). For this, we have performed in vitro (stability studies) and in vivo assays (corneal permanence time measured directly by Positron Emission Tomography) of three potential formulations. Next, the best formulation was selected, and its toxicological profile and clinical effectiveness have been evaluated. The biopermanence studies (direct measurements and PET/CT) showed that the formulations with PVA and Hyaluronic Acid present more retention time on the ocular surface of rats than PBS. From the stability study, we have determined that tacrolimus with PVA in cold storage is the best option. Tacrolimus with PVA has shown lower cytotoxicity than cyclosporine at early times. On the other hand, the pilot study performed has shown significant improvements in patients, with no noticeable adverse reactions. Based on stability, biopermanence, safety and clinical effectiveness studies, we concluded that tacrolimus-PVA eye drops are a suitable candidate for its clinical application in inflammatory ophthalmology diseases.

Topical tacrolimus in anterior segment inflammatory disorders

Immune mediated inflammatory anterior segment diseases are variable and their management requires intense immunosuppression. Treatment with topical steroids is associated with serious ocular side effects. In order to overcome the potentially blinding complications of topical steroids, immunomodulatory drugs are being used more frequently. Tacrolimus is a calcineurin inhibitor that induces suppression of T lymphocytes activity and reduction of ocular inflammation. Tacrolimus was recently investigated for application in various anterior segment inflammatory disorders. In this review, we will discuss the therapeutic application of topical tacrolimus as a steroid-sparing agent in treating T cell mediated anterior segment inflammation.

Update on the Management of High-Risk Penetrating Keratoplasty

PURPOSE OF REVIEW

In this article, we review the indications and latest management of high-risk penetrating keratoplasty.

RECENT FINDINGS

Despite the immune-privilege status of the cornea, immune-mediated graft rejection still remains the leading cause of corneal graft failure. This is particularly a problem in the high-risk graft recipients, namely patients with previous graft failure due to rejection and those with inflamed and vascularized corneal beds. A number of strategies including both local and systemic immunosuppression are currently used to increase the success rate of high-risk corneal grafts. Moreover, in cases of limbal stem cell deficiency, limbal stem cells transplantation is employed.

SUMMARY

Corticosteroids are still the top medication for prevention and treatment in cases of corneal graft rejection. Single and combined administration of immunosuppressive agents e.g. tacrolimus, cyclosporine and mycophenolate are promising adjunctive therapies for prolonging graft survival. In the future, cellular and molecular therapies should allow us to achieve immunologic tolerance even in high-risk grafts.

Systemic Immunomodulatory Strategies in High-risk Corneal Transplantation

The cornea is the most commonly transplanted tissue in the body. Although corneal grafts generally have high success rates, transplantation onto inflamed and vascularized host beds, or so-called high-risk corneal transplantation, has a high rate of graft rejection. The management of this high-risk corneal transplantation is challenging and involves numerous measures. One of the key measures to prevent graft rejection in these cases is the use of systemic immunosuppressive agents. In this article, we will review the systemic immunosuppressive agents most commonly used for high-risk corneal transplantation, which include corticosteroids, cysclosporine A, tacrolimus, mycophenolate mofetil, and rapamycin. Benefits, risks, and published data on the use of these medications for high-risk corneal transplantation will be detailed. We will also summarize novel immunoregulatory approaches that may be used to prevent graft rejection in high-risk corneal transplantation.

Management of high-risk corneal transplantation

The cornea is the most commonly transplanted tissue in medicine. The main cause of corneal graft failure is allograft rejection. The incidence of graft rejection depends on the presence of high-risk characteristics, most notably corneal neovascularization. Although corneal grafting has high success rates in the absence of these risk factors, high-risk keratoplasty is associated with low success rates because of a high incidence of immune-mediated graft rejection. To improve the survival of high-risk corneal transplantation, various preoperative, intraoperative, and postoperative measures can be considered; however, the key step in the management of these grafts is the long-term use of local and/or systemic immunosuppressive agents. Although a number of immunosuppressive agents have been used for this purpose, the results vary significantly across different studies. This is partly due to the lack of an optimized method for their use, as well as the lack of a precise stratification of the degree of risk in each individual patient. New targeted biologic treatments, as well as tolerance-inducing methods, show promising horizons in the management of high-risk corneal transplantation in near future.

Systemic Immunosuppression in High-Risk Penetrating Keratoplasty: A Systematic Review

Cornea transplantation has a high success rate and typically only requires topical immunomodulation. However, in high-risk cases, systemic immunosuppression can be used. We conducted a systematic review on the efficacy and side effects of systemic immunosuppression for high-risk cornea transplantation. The study population was 18 years old or older with a high-risk transplant (two or more clock hours of cornea vascularization or a previous failed graft or a graft needed because of herpes simplex keratitis). A comprehensive search strategy was performed with the help of an information specialist and content experts from ophthalmology. All study designs were accepted for assessment. Level 1 and level 2 screening was performed by two reviewers followed by data abstraction. Forest plots were created whenever possible to synthesize treatment effects. Quality assessment was done with a Downs and Blacks score. From 1,150 articles, 29 were ultimately used for data abstraction. The odds ratios (ORs) for clear graft survival in cyclosporine and controls were 2.43 (95% CI: 1.00 - 5.88) and 3.64 (95% CI: 1.48 - 8.91) for rejection free episodes. Mycophenolate mofetil (MMF) significantly improved the rejection free graft survival rates at 1 year (OR: 4.05, 95% CI: 1.83 - 8.96). The overall results suggested that both systemic cyclosporine and MMF improved 1-year rejection free graft survival in high-risk keratoplasty. Cyclosporine also significantly improved clear graft survival rates at 1 year; however, there were insufficient data to analyze the same in the MMF group. Higher quality studies are needed to understand this issue better.

[Risk factors, clinical presentations, prevention, and treatment of corneal graft rejection]

Corneal transplantation is the most common and successful type of allotransplantation surgery. Post-transplant immune response in keratoplasty is less pronounced than that in other transplantation procedures, which is accounted for by anatomical features of the cornea and, also, its low antigenic potential and active immunosuppression. However, the immune privilege of the cornea can be violated by neovascularization, inflammation, or trauma. Patients who require keratoplasty to restore their sight and whose immune privilege is disturbed, fall into a high-risk group and are likely to demonstrate tissue incompatibility and non-transparent engraftment. Two approaches exist as to how graft rejection can be prevented. One of them involves induction of donor-specific tolerance, the other - non-specific suppression of the recipient's immune response. To avoid tissue incompatibility, measures can be taken to restore the immune privilege of the cornea as well as to induce antigen-specific tolerance, which is considered a promising, thought yet experimental, area of modern transplantology. In clinical practice, one pays most attention to improvement of non-specific immune suppression methods based on interfering in the metabolism of immunocompetent cells. Thus, timely prescriptions and proper immunosuppressive tactics with account to possible risk factors determine the outcome in high-risk patients undergoing corneal transplantation surgery.

Efficacy and safety of systemic tacrolimus in high-risk penetrating keratoplasty after graft failure with systemic cyclosporine

PURPOSE

The aim of this study was to investigate the efficacy and safety of systemic tacrolimus for the treatment of eyes that developed graft failure despite treatment with cyclosporine (CsA).

METHODS

Ten eyes of 10 patients who underwent high-risk penetrating keratoplasty (PKP) and developed graft failure despite treatment with systemic CsA were included in this study. The patients underwent PKP and were treated with systemic tacrolimus according to the standardized protocol.

RESULTS

Treatment with tacrolimus was continued for 18.1 ± 13.9 months. The median duration of corneal graft clarity was 34.5 months. Graft rejection occurred in 2 of 10 eyes during a mean follow-up period of 48.9 ± 22.9 months. Kaplan-Meier survival plots showed significantly fewer graft rejection episodes (P = 0.033) and longer graft survival (P = 0.042) after treatment with tacrolimus compared those with CsA. Tacrolimus was discontinued in 2 patients; 1 had renal dysfunction and the other had muscle pain and fatigue. These side effects subsided after discontinuation of tacrolimus.

CONCLUSIONS

Treatment with systemic tacrolimus is possibly safe and effective in reducing graft rejection and prolonging graft survival in patients with high-risk PKP after graft failure with systemic CsA.

Long-term result of maintenance treatment with tacrolimus ointment in chronic ocular graft-versus-host disease

PURPOSE

To investigate the efficacy and safety of long-term maintenance treatment with tacrolimus ointment in chronic ocular graft-vs-host disease (GVHD) with ocular surface inflammation.

DESIGN

A retrospective interventional consecutive case series.

METHOD

Long-term maintenance treatment (≥6 months) with topical 0.02% tacrolimus ointment was applied to patients with chronic ocular GVHD with ocular surface inflammation (at least grade 2 inflammatory score). We evaluated the inflammatory score, steroid score and steroid use period of total duration, and numbers of inflammatory aggravations before and after tacrolimus treatment. The clinical outcomes were assessed by symptom score, ocular surface staining, Schirmer I test, tear break-up time (TBUT), and classification of chronic GVHD conjunctivitis at the initial and final examinations.

RESULTS

Thirteen patients (24 eyes) were treated with tacrolimus ointment for up to 20 months (average 12.2 months). The ocular surface inflammatory score decreased from 2.8 to 0.6 (P = .001) within 2-8 weeks after starting tacrolimus ointment treatment. The numbers of inflammatory aggravation and the need for steroid treatment also decreased after initiating tacrolimus treatment. At the final follow-up, all patients reported improvement in clinical outcomes, compared to initial findings. Except for blurred vision or mild burning sensation, there were no reported side effects.

CONCLUSION

Considering the chronic course of GVHD, long-term maintenance treatment with tacrolimus ointment could be useful and safe to locally treat ocular surface inflammation in chronic ocular GVHD.

Matching for Human Leukocyte Antigens (HLA) in corneal transplantation - to do or not to do

As many patients with severe corneal disease are not even considered as candidates for a human graft due to their high risk of rejection, it is essential to find ways to reduce the chance of rejection. One of the options is proper matching of the cornea donor and recipient for the Human Leukocyte Antigens (HLA), a subject of much debate. Currently, patients receiving their first corneal allograft are hardly ever matched for HLA and even patients undergoing a regraft usually do not receive an HLA-matched graft. While anterior and posterior lamellar grafts are not immune to rejection, they are usually performed in low risk, non-vascularized cases. These are the cases in which the immune privilege due to the avascular status and active immune inhibition is still intact. Once broken due to infection, sensitization or trauma, rejection will occur. There is enough data to show that when proper DNA-based typing techniques are being used, even low risk perforating corneal transplantations benefit from matching for HLA Class I, and high risk cases from HLA Class I and probably Class II matching. Combining HLA class I and class II matching, or using the HLAMatchmaker could further improve the effect of HLA matching. However, new techniques could be applied to reduce the chance of rejection. Options are the local or systemic use of biologics, or gene therapy, aiming at preventing or suppressing immune responses. The goal of all these approaches should be to prevent a first rejection, as secondary grafts are usually at higher risk of complications including rejections than first grafts.

Keratoplasty postoperative treatment update

Immunosuppressive therapy is the main postoperative treatment for keratoplasty, but there are considerable differences in protocols for the use of steroids and other immunosuppressants. Therefore, we conducted 2 prospective randomized clinical trials and 1 prospective nonrandomized clinical trial on keratoplasty postoperative treatment. One study evaluated the efficacy and safety of long-term topical corticosteroids after a penetrating keratoplasty was performed. Patients who underwent keratoplasty and maintained graft clarity for >1 year were randomly assigned to either a steroid or a no-steroid group. At the 12-month follow-up, the no-steroid group developed significantly more endothelial rejection than did the steroid group. A second study elucidated the effectiveness and safety of systemic cyclosporine in high-risk corneal transplantation. The patients were assigned to a systemic cyclosporine or control group. At a mean follow-up of 42.7 months, no difference was observed in the endothelial rejection rates and graft clarity loss between the 2 groups. A third study elucidated the effectiveness and the safety of systemic tacrolimus in high-risk corneal transplantation. Of 11 consecutive eyes decompensated despite systemic cyclosporine treatment, there was no irreversible rejection in eyes treated with tacrolimus, which was significantly better than in previous penetrating keratoplasty with systemic cyclosporine treatment. Prognosis after keratoplasty in patients with keratoconus is relatively good, but special attention is required for patients with atopic dermatitis. Postkeratoplasty atopic sclerokeratitis (PKAS) is a severe form of sclerokeratitis after keratoplasty in atopic patients. Our retrospective study showed that 35 eyes of 29 patients from a total of 247 keratoconus eyes undergoing keratoplasty were associated with atopic dermatitis, of which 6 eyes of 5 patients developed PKAS. Eyes with PKAS had a significantly higher incidence of atopic blepharitis and preoperative corneal neovascularization, and therefore, we suggest systemic corticosteroids or cyclosporine to prevent PKAS in such high-risk cases.

Tim-1 blockade with RMT1-10 increases T regulatory cells and prolongs the survival of high-risk corneal allografts in mice

Anti-Tim-1 monoclonal antibody (mAb) RMT1-10 is effective in promoting allograft survival through blocking Tim-1. However, its role in corneal transplantation is unclear. This study aims to evaluate the effect of RMT1-10 on high-risk corneal transplantation. BALB/c mice were transplanted with corneal grafts from C57BL/6 mice and intraperitoneally injected with RMT1-10 or isotype IgG. The transparency of corneal graft was evaluated by slit lamp biomicroscopy. Flow cytometry was used to determine the phenotype of CD4(+) T cells, including CD154, Tim-3, CD25 and Foxp3, and to analyze the proliferation capacity of CD4(+) T cells and the suppressive capacity of T regulatory (Treg) cells. The levels of interferon-gamma (IFN-γ), IL-4 and transforming growth factor-beta1 (TGF-β1) were investigated by intracellular staining and/or ELISA assay. The delayed-type hypersensitivity (DTH) response was evaluated by ear swelling assay. RMT1-10 therapy delayed the onset of rejection and significantly prolonged the survival of corneal allograft. In RMT1-10 treated mice, percentages of CD4(+)CD154(+) cells and CD4(+)Tim-3(+) cells were significantly decreased while the frequency of CD4(+)CD25(+)Foxp3(+) Treg cells was significantly up-regulated, compared with those of isotype IgG treated mice. And, in vitro proliferation of CD4(+) T cells was significantly inhibited by RMT1-10. In addition, percentage of intracellular expression of IFN-γ and IL-4 in CD4(+) T cells isolated from RMT1-10 treated mice was significantly reduced. After co-culturing with RMT1-10 in vitro, CD4(+) T cells produced significantly decreased levels of IFN-γ and IL-4 and significantly increased levels of TGF-β1. Furthermore, RMT1-10 inhibited DTH response of recipient mice and enhanced the suppressive capacity of Treg cells isolated from RMT1-10 treated mice. Our data indicate that Tim-1 blockade with RMT1-10 could suppress immunological rejection and prolong the survival of corneal allograft through regulating T cell responses.

Topical 0.03% tacrolimus preventing rejection in high-risk corneal transplantation: a cohort study

BACKGROUND/AIMS

The present study aims to identify the rate of rejection and safety of 0.03% tacrolimus eye drops associated with 1% prednisolone in a topical formulation, comparing them with the use of 1% prednisolone eye drops alone in patients with high-risk corneal transplantation.

METHODS

Retrospective cohort study with 72 patients (72 eyes) who underwent more than one penetrating keratoplasty (PK) in the same eye or had severe chemical burn between 2004 and 2011 in the department of cornea and external disease of the Clinical Hospital of Porto Alegre, Brazil. We compared the records of 36 patients that performed unilateral PK and received only 1% prednisolone eye drops between May 2004 and July 2008, with 36 patients that received 0.03% tacrolimus eye drops in addition to 1% prednisolone between August 2008 and August 2011.

RESULTS

The mean follow-up of the group exposed to tacrolimus was 23.1 months and 24.0 in the prednisolone alone group. The demographics, intraoperative and initial indications for first PK were similar between groups, as well as the number of regrafts performed. Intraocular pressure (IOP) was not statistically different among groups. Regarding irreversible rejections, topical tacrolimus showed greater protection: only seven grafts (19.4%) lost transparency against 16 (44.4%) in the 1% prednisolone alone group (p <0.05).

CONCLUSIONS

Topical 0.03% tacrolimus was effective in preventing irreversible rejection in patients with high-risk corneal transplantation without increasing IOP.

Gene therapy in corneal transplantation

Corneal transplantation is the most commonly performed organ transplantation. Immune privilege of the cornea is widely recognized, partly because of the relatively favorable outcome of corneal grafts. The first-time recipient of corneal allografts in an avascular, low-risk setting can expect a 90% success rate without systemic immunosuppressive agents and histocompatibility matching. However, immunologic rejection remains the major cause of graft failure, particularly in patients with a high risk for rejection. Corticosteroids remain the first-line therapy for the prevention and treatment of immune rejection. However, current pharmacological measures are limited in their side-effect profiles, repeated application, lack of targeted response, and short duration of action. Experimental ocular gene therapy may thus present new horizons in immunomodulation. From efficient viral vectors to sustainable alternative splicing, we discuss the progress of gene therapy in promoting graft survival and postulate further avenues for gene-mediated prevention of allogeneic graft rejection.

Application for tacrolimus ointment in treating refractory inflammatory ocular surface diseases

PURPOSE

To evaluate the therapeutic effects of topical tacrolimus ointment on refractory inflammatory ocular surface diseases.

DESIGN

Retrospective interventional consecutive case series.

METHODS

In Severance Hospital, Seoul, South Korea, 0.02% tacrolimus ointment was topically applied 1 to 3 times per day, depending on disease severity, for up to 31 months in eyes of 12 consecutive patients with refractory inflammatory ocular surface diseases who had previously been treated with steroid therapy. Seven patients had chronic cicatrizing conjunctivitis (6 cases caused by Stevens-Johnson syndrome and 1 attributable to ocular cicatricial pemphigoid); 4 had scleritis (3 necrotizing scleritis, 1 recurrent nodular scleritis); and 1 patient had Mooren ulcer with corneal perforation. The therapeutic outcomes after tacrolimus treatment were evaluated according to the following criteria: change in clinical findings (eg, decrease of hyperemia, ocular pain, epithelial defect, and pseudomembrane), intraocular pressure (IOP), and need for steroid therapy.

RESULTS

In all 3 groups, tacrolimus showed an immunosuppressive effect, especially on scleritis and Mooren ulcer. These effects included suppression of corneoscleral melting and reduction of hyperemia. In chronic cicatrizing conjunctivitis, simultaneous topical tacrolimus while tapering steroid therapy suppressed inflammatory relapse. The elevated IOP in steroid responders recovered to normal range after successful tapering of steroid. No adverse side effects were noted after 1.5 to 31 months of continuous tacrolimus treatment.

CONCLUSION

The use of topical tacrolimus ointment is effective in controlling refractory inflammatory ocular surface disease, and can reduce the need for steroid use while reducing inflammation recurrence.

Corneal Allograft Rejection: Immunopathogenesis to Therapeutics

Corneal transplantation is among the most successful solid organ transplants. However, despite low rejection rates of grafts in the ‘low-risk’ setting, rejection can be as high as 70% when grafted into ‘high-risk’ recipient beds. Under normal homeostatic conditions, the avascular cornea provides a unique environment that facilitates immune and angiogenic privilege. An imbalance in pro-inflammatory, angiogenic and lymphangiogenic mediators leads to a breakdown in corneal immune privilege with a consequent host response against the donor graft. Recent developments in lamellar and endothelial keratoplasties have reduced the rates of graft rejection even more, while providing improved visual outcomes. The corneal layer against which an immune response is initiated, largely determines reversibility of the acute episode. While epithelial and stromal graft rejection may be treated with topical corticosteroids with higher success, acute endothelial rejection mandates a more aggressive approach to therapy due to the lack of regenerative capacity of this layer. However, current immunosuppressive regimens come with the caveat of ocular and systemic side effects, making prolonged aggressive treatment undesirable. With the advent of biologics, efficacious therapies with a superior side effect profile are on the horizon. In our review we discuss the mediators of ocular immune privilege, the roles of cellular and molecular immune players in graft rejection, with a focus on human leukocyte antigen and antigen presenting cells. Furthermore, we discuss the clinical risk factors for graft rejection and compare rates of rejection in lamellar and endothelial keratoplasties to traditional penetrating keratoplasty. Lastly, we present the current and upcoming measures of therapeutic strategies to manage and treat graft rejection, including an overview of biologics and small molecule therapy.

Corneal transplantation

Corneal transplantation or keratoplasty has developed rapidly in the past 10 years. Penetrating keratoplasty, a procedure consisting of full-thickness replacement of the cornea, has been the dominant procedure for more than half a century, and successfully caters to most causes of corneal blindness. The adoption by specialist surgeons of newer forms of lamellar transplantation surgery, which selectively replace only diseased layers of the cornea, has been a fundamental change in recent years. Deep anterior lamellar keratoplasty is replacing penetrating keratoplasty for disorders affecting the corneal stromal layers, while eliminating the risk of endothelial rejection. Endothelial keratoplasty, which selectively replaces the corneal endothelium in patients with endothelial disease, has resulted in more rapid and predictable visual outcomes. Other emerging therapies are ocular surface reconstruction and artificial cornea (keratoprosthesis) surgery, which have become more widely available because of rapid advances in these techniques. Collectively, these advances have resulted in improved outcomes, and have expanded the number of cases of corneal blindness, which can now be treated successfully. Femtosecond-laser-assisted surgery, bioengineered corneas, and medical treatment for endothelial disease are also likely to play a part in the future.

Adverse effects of systemic immunosuppression in keratolimbal allograft

Purpose. Keratolimbal allograft (KLAL) is a treatment for limbal stem cell deficiency. One disadvantage is systemic immunosuppression to avoid rejection. Our purpose was to examine the adverse effects of systemic immunosuppression in KLAL. Methods. A retrospective case review of 16 patients with KLAL who received systemic immunosuppression consisting of a corticosteroid, an antimetabolite, and/or a calcineurin inhibitor was performed. Patients were monitored for signs, symptoms, or laboratory evidence of toxicity. Results. Eleven of 16 patients (68%) experienced an adverse effect. The average age of those with adverse effects was 43.5 years and without was 31.4 years. Ten of 11 patients (91%) had resolution during mean followup of 16.4 months. No serious adverse effects occurred. The most common included anemia, hyperglycemia, elevated creatinine, and elevated liver function tests. Prednisone and tacrolimus were responsible for the most adverse effects. Patients with comorbidities were more likely to experience an adverse effect (82% versus 20%, P = 0.036). Conclusions. KLAL requires prolonged systemic immunosuppression. Our data demonstrated that systemic immunosuppression did not result in serious adverse effects in our population and is relatively safe with monitoring for toxicity. In addition, we demonstrated that adverse effects are more likely in older patients with comorbidities.

Management and clinical outcome of penetrating keratoplasty for long-term corneal changes in sympathetic ophthalmia

Purpose. To report the visual outcome of penetrating keratoplasty performed on the sympathizing eye in three cases of sympathetic ophthalmitis. Methods. Interventional case series of three patients, diagnosed with sympathetic ophthalmitis, with corneal changes in the form of band keratopathy and decompensation underwent penetrating keratoplasty to the sympathizing eye. They had each sustained penetrating trauma as a child and had undergone previous cataract surgery and superficial keratectomy. Two patients had undergone lamellar keratoplasty prior to this procedure. One patient had undergone trabeculectomy for glaucoma, and she was on antiglaucoma medication. The preoperative visual acuity was 1/60 in the affected eye of each patient. Penetrating keratoplasty was performed in the sympathizing eye and the donor graft size was 7.50 mm, and the host graft size was 7.25 mm. Our patients were immunosuppressed prior to the procedure to help prevent graft rejection. Result. At one year follow-up, a BCVA of 6/36 or better was achieved in all three patients. Postoperative examination of the fundus showed peripheral chorioretinal atrophy with pigmentary changes at the macula, accounting for the limited vision. The grafts remain clear to date, and there has been no recurrence of uveitis or rejection. Conclusion. Penetrating keratoplasty can be considered as a surgical option to restore useful vision in a stable sympathizing eye in sympathetic ophthalmitis, and this depends on the extent of the pathology. However, these cases require treatment with immunosuppressives to prevent graft rejection and to prolong graft survival.

Prospective, randomized study of the efficacy of systemic cyclosporine in high-risk corneal transplantation

PURPOSE

Immunologic rejection remains a major cause of graft failure in high-risk corneal transplantation. This study was conducted to elucidate the efficacy and safety of systemic cyclosporine (CsA) in high-risk corneal transplantation.

DESIGN

Prospective, randomized, open-labeled clinical trial with a parallel-group study.

METHODS

Patients underwent high-risk corneal transplantation at the Department of Ophthalmology, Tokyo Dental College, Chiba, Japan. High-risk was defined as corneal neovascularization in more than 1 quadrant or a history of corneal grafting. Patients were assigned to either a systemic CsA group or a control group. Administration of CsA was continued for at least 6 months with blood CsA concentration 2 hours after administration of approximately 800 ng/mL, unless undesirable side effects developed. The main outcome measures were graft clarity, endothelial rejection, and local and systemic complications.

RESULTS

Forty patients were enrolled and 39 (18 men, 21 women; mean age, 67.4 ± 11.9 years) were analyzed. In the CsA group, CsA was discontinued within 6 months in 7 patients because of side effects. With a mean follow-up of 42.7 months, endothelial rejection developed in 6 and 2 eyes in the CsA and control groups, respectively. No differences were observed in the rates of graft clarity loss between the 2 groups (P = .16, Kaplan-Meier analysis).

CONCLUSIONS

No positive effect of systemic CsA administration for suppressing rejection in high-risk corneal transplantation was observed. With a relatively high incidence of systemic side effects, the results suggest that this protocol should not be recommended for corneal transplant recipients, especially those of advanced age.

Graft rejection and graft failure after anterior lamellar versus penetrating keratoplasty

PURPOSE

To compare anterior lamellar keratoplasty (ALK) with the reference surgical technique (penetrating keratoplasty [PK]) for risk of rejection.

DESIGN

Retrospective, comparative case series.

METHODS

setting: Institutional. patients: One hundred forty-nine consecutive ALK procedures (ALK group) and 149 matched PK procedures (PK group) performed for optical indication in eyes with corneal diseases not involving the corneal endothelium (ie, keratoconus, scars after infectious keratitis, stromal dystrophies, and trauma). main outcome measures: Three-year graft survival and cumulative incidence of rejection episodes.

RESULTS

The 3-year overall graft survival was 98.3% in the ALK group and 94.3% in the PK group (P = .03). The 3-year cumulative incidence of irreversible rejection was 0.0% in the ALK group and 5.2% in the PK group (P = .02). The 3-year cumulative incidence of rejection episodes was 10.0% in the ALK group and 23.2% in the PK group (P = .01). The average graft-to-rejection episode time was 21.6 ± 22.0 months in the PK group and 19.4 ± 12.7 months in the ALK group (P = .76).

CONCLUSIONS

ALK techniques dramatically decrease the risk of irreversible endothelial and stromal rejection after corneal transplantation. Immune-mediated rejection episodes are observed after ALK, but its lower graft failure rate compared with PK is at least partly the result of the absence of endothelial rejection. In addition, the incidence of rejection episodes after ALK was 50% less than that observed after PK.

Donor site complications in autolimbal and living-related allolimbal transplantation

OBJECTIVE

To study the long-term changes at donor sites and safety implications for donor eyes used for harvesting tissue for autologous and living-related donor limbal transplants.

DESIGN

Retrospective, observational, consecutive case series.

PARTICIPANTS

We examined 50 donor sites of limbal tissue belonging to 25 healthy eyes (23 human subjects).

METHODS

The corneas and limbus of donor eyes were assessed for symptoms and visual acuity and examined by slit-lamp biomicroscopy and in vivo confocal microscopy with particular emphasis on the donor sites and central cornea.

MAIN OUTCOME MEASURES

In the donor eyes, we assessed visual acuity, persistence of symptoms, stability of the corneal epithelium, and the clinical and microscopic changes that occurred at the donor sites.

RESULTS

Mean follow-up was 41±38 months (median, 24; range, 3-127). All eyes had symptoms of ocular discomfort up to 4 weeks postoperatively and remained asymptomatic thereafter. No patient reported subjective reduction in visual acuity. Mean best-corrected visual acuity (logarithm of the minimum angle of resolution fraction) preoperatively was 0.076±0.19 and postoperatively was 0.09±0.17 (P = 0.57). All donor sites showed re-epithelialization of the peripheral denuded limbus within 2 weeks. Observed complications were filamentary keratitis and subconjunctival hemorrhage in 4 eyes. In vivo confocal microscopy confirmed that the central corneal epithelium remained normal in all eyes. The re-epithelialized donor site was covered with conjunctival epithelium in 17 sites of 10 eyes and with corneal epithelium in 7 sites of 5 eyes.

CONCLUSIONS

Limbal donation of 2 clock-hours of the superior and inferior limbus with 3×3 mm of adjacent conjunctiva was a safe procedure in this group of patients, demonstrating stable vision and an intact corneal epithelium during the follow up period. Donor sites can be re-epithelized by multiple layers of either corneal or conjunctival epithelium and is associated with deep stromal scarring.