Topical cyclosporine in pediatric keratoplasty

Pediatric corneal transplantation: techniques, challenges, and outcomes

Pediatric corneal transplant is a highly demanding and technically challenging procedure for the cornea surgeon in today's era. These cases pose unique challenges in clinical and surgical management. The indications of pediatric corneal transplant can be therapeutic, tectonic, optical, and cosmetic. Pediatric patients undergoing corneal transplants are at a high risk of graft infection, failure, rejection, dehiscence, and amblyopia due to young age, robust immune system, increased incidence of trauma, and compliance issues. The other factors contributing to graft failure can be allograft rejection, secondary glaucoma, corneal vascularization, multiple surgeries, vitreous prolapse, and lack of treatment compliance. A successful corneal transplant in children depends on meticulous preoperative evaluation, uneventful surgery, the expertise of a corneal surgeon, and regular and timely postoperative follow-up. Therapeutic and optical penetrating keratoplasty are the most commonly performed transplants in children. However, with the advancements in surgical technique and management protocol, the current focus has shifted toward lamellar keratoplasty. Lamellar keratoplasty offers early visual recovery and potentially fewer complications. Visual rehabilitation through corneal transplant in otherwise blind eyes can be a boon for the children. Recently, keratoprostheses have been promising in children with multiple graft failures. The current review gives insights into epidemiology, etiology, indications, clinical characteristics, investigations, management options, recent advances, and the future of pediatric corneal transplants. As surgical techniques continue to grow and comprehension of pediatric corneal transplants is improving, we can safeguard these eyes with the best possible anatomical and functional outcomes.

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.

Surgical Antimicrobial Prophylaxis in Patients of Neonatal and Pediatric Age Subjected to Eye Surgery: A RAND/UCLA Appropriateness Method Consensus Study

Ocular surgery encompasses a wide range of procedures, including surgery of the tear ducts, eyelid, cornea and conjunctiva, lens, ocular muscle, and vitreoretinal and iris surgery. Operations are also performed for the removal of tumors, repairs of ocular trauma and, finally, corneal transplantation. Antibiotic prophylaxis for the prevention of surgical site infections (SSIs) in ocular surgery is a complex field in which shared lines of action are absent. In light of the scarcity of shared evidence in the use of ocular antimicrobial prophylaxis for the pediatric population, this consensus document aims to provide clinicians with a series of recommendations on antimicrobial prophylaxis for patients of neonatal and pediatric age undergoing eye surgery. The following scenarios are considered: (1) intraocular surgery; (2) extraocular surgery; (3) ocular trauma; (4) ocular neoplasm; (5) ocular surface transplantations; (6) corneal grafts. This work has been made possible by the multidisciplinary contribution of experts belonging to the most important Italian scientific societies and represents, in our opinion, the most complete and up-to-date collection of recommendations regarding clinical actions in the peri-operative environment in eye surgery. The application of uniform and shared protocols aims to improve surgical practice, through the standardization of procedures, with a consequent reduction of SSIs, also limiting the phenomenon of antimicrobial resistance.

Penetrating keratoplasty in children under 3 years old with congenital corneal opacities

AIM

To evaluate the graft rejection and visual outcomes after penetrating keratoplasty (PK) in the presence of various congenital corneal opacities in children.

METHODS

In this retrospective cohort study, children who underwent PK were then followed for 5y. The patient's medical records were collected from June 2014 until June 2019 and analyzed in December 2019. All patients were children under three years old with congenital corneal opacities with or without microcornea who came to a pediatric ophthalmologist and underwent PK in Jakarta Eye Center (JEC). Beforehand, all children have participated in a thorough evaluation for PK. In the case of severe microcornea was not advised to undergo surgery. The visual outcomes and graft survival rate were described in percentages. The graft survival plot was presented with Kaplan-Meier, while the visual acuity was analyzed using the Wilcoxon signed ranks test.

RESULTS

Sixteen eyes from eleven patients (seven girls and four boys) underwent PK. The graft survival rate of the first 6, 12, and 18 mo later of keratoplasty was 100%, 83.3%, and 66.7%, respectively. The overall mean survival time is 22mo (standard error 2.419), and no significant difference between the patients underwent PK before and after 36mo of their age (P=0.52). The graft failure was 50%, and post-surgery complications included cataract 43.7%, band keratopathy 12.5%, and scleromalasia 6.25%. Wilcoxon test analysis of visual acuity post keratoplasty was not statistically significant (P=0.34), while overall showed 44% improvements of visual outcome for 5y of follow-up. With a good survival at one year up to 22mo (83.3%), the visual acuity could be achieved (63%), and showed improvements (44%) during follow-up.

CONCLUSION

The complications are frequent for pediatric PK. Thus, corneal surgery on infants requires careful case selection, adequate pre-operative evaluation, skilled surgery (optical correction), very close cooperation family-physician, intensive post-operation care, and amblyopia management in the future.

Topical corticosteroids with topical cyclosporine A versus topical corticosteroids alone for immunological corneal graft rejection

PURPOSE

To assess the efficacy and safety of supplementing topical cyclosporine A (CsA) to topical corticosteroids (CS), in the prophylaxis and treatment of corneal graft rejection following penetrating keratoplasty (PK).

METHODS

Meta-analysis. Search was performed in PubMed, CENTRAL, ClinicalTrials.gov, reference lists of articles and conference proceedings. Primary outcomes: 1-year rejection-free survival rate (prophylaxis); resolution rate of rejection episodes (treatment). Secondary outcomes: 6- and 24-month rejection-free graft survival rate, number of rejection episodes during follow-up, time-to-resolution of rejection episode, 12- and 24-months graft survival rate, adverse events. Subgroup analyses were planned for high-risk grafts; primary vs. secondary prophylaxis of graft rejection episodes; and CsA concentrations of 0.05%, 1%, and 2%.

RESULTS

Five studies of moderate methodological quality were included (one retrospective, four RCT), assessing 459 eyes (CS + CsA 226, CS 233). In the prophylaxis setting, supplemental CsA was associated with a higher rejection-free survival rate at 12-months (RR 1.25, 95% CI: 1.00-1.56, p = 0.05) and 24-months post-PK (RR 1.56, 95% CI: 1.15-2.11, p < 0.01), though no differences were found at the 6-months timepoint (p = 0.93). This effect was mostly verified using CsA 2% in the high-risk subset of patients. In the treatment setting, no differences were found in the resolution rate of rejection episodes (p = 0.23). No differences existed on drug-related adverse events.

CONCLUSION

In the prophylaxis of rejection episodes post-PK, the combined regimen of CS + CsA was associated with a higher 1- and 2-year rejection-free graft survival rate. Subgroup analysis mostly supported the use of CsA 2% for high-risk grafts. Further studies are needed to validate these results.

Pediatric keratoconus - Current perspectives and clinical challenges

Keratoconus is an ectatic corneal disease characterized by progressive stromal thinning, irregular astigmatism, and defective vision. It can be unilateral or bilateral with asymmetric presentation. It starts at puberty and either progresses rapidly to an advanced stage of the disease or stops in case of delayed onset and slow progression. Pediatric keratoconus is more aggressive than in adults and the management protocols differ because of various rationales such as accelerated progression, advanced stage of disease at the time of diagnosis and co-morbidities. It poses a burden to the society as it affects the quality of life, social, and educational development in children. Hence early diagnosis, recognition of progression, and timely intervention with collagen crosslinking is imperative to arrest the worsening. Association with systemic syndromes and ocular comorbidities can be of concern in pediatric keratoconus. Severe ocular allergy when associated hastens progress and complicates timely intervention of crosslinking treatment and compliance to contact lens wear. Keratoplasty in pediatric keratoconus has good outcomes but can encounter frequent suture-related concerns. This article discusses the epidemiology, etiopathogenesis, clinical challenges, and current perspectives of management of pediatric keratoconus.

Indications and outcomes of pediatric keratoplasty in a tertiary eye care center: A retrospective review

To evaluate indications and outcomes of pediatric keratoplasty in a tertiary eye center, and identify factors that affect visual outcomes.We performed a retrospective review of penetrating keratoplasty in children aged 0 to 18 years between 1995 and 2011 in the Asociación para Evitar la Ceguera en México IAP, Hospital "Dr. Luis Sánchez Bulnes".A total of 574 penetrating keratoplasties were performed during the study interval. Median follow-up was 5.0 years. Main indications included keratoconus (55.58%), postherpetic scarring (9.58%), traumatic opacities (7.49%), and bullous keratopathy (6.09%). Rejection rates at 5 years were 27% overall, and among indications, keratoconus showed the best graft survival at 60-months follow-up (85%). The percentage of patients with best corrected visual acuity (BCVA) posttransplant >20/400 at 5 years in the nonrejection group was 81.25% and 82.74% in < and > 10 years of age (YOA) groups, respectively, versus a BCVA posttransplant > 20/400 at 5 years in the rejection group of 53.68% and 51.72% in < and > 10 YOA groups, respectively. There was a statistically significant reduced rejection rate between genders at 18 months of follow-up, favoring males.Despite being considered a high-risk procedure in children, penetrating keratoplasty can achieve good results, especially in patients with keratoconus. It can achieve significative improvements of visual acuity, provided there is an adequate follow-up and treatment adherence.

The challenging management of pediatric corneal transplantation: an overview of surgical and clinical experiences

PURPOSE

Pediatric keratoplasty is an immense challenge because of the technical complexity of the procedure and the high risk of rejection in young graft recipients. Our aim is to describe the major indications and appropriate timing of corneal transplantation intervention, including a report of our experience and surgical tips, in conjunction with the current literature.

METHODS

Review of the literature on indications for keratoplasty in pediatric patients classified as: congenital, traumatic and acquired non-traumatic opacities. We additionally explored the challenges corneal surgeons face in performing this type of surgery and review the most pressing transplant-related problems and their management.

RESULTS

Outcomes after pediatric keratoplasty, in terms of visual development, restoration and clarity of the graft, are influenced by peri-operative local and systemic conditions and factors, and by intraoperative management of the transplantation procedure itself.

CONCLUSION

Pediatric corneal transplantation is a critical tool for visual restoration and development in young patients with corneal opacities, particularly during the critical period of visual development. Successful management of the significant challenges associated with pediatric keratoplasty requires customized clinical and surgical management of each patient with particular attention paid to proper post-operative rehabilitation.

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.

Laser Scanning In Vivo Confocal Microscopy of Clear Grafts after Penetrating Keratoplasty

PURPOSE

To evaluate the changes of keratocytes and dendritic cells in the central clear graft by laser scanning in vivo confocal microscopy after penetrating keratoplasty (PK).

METHODS

Thirty adult subjects receiving PK at Shandong Eye Institute and with clear grafts and no sign of immune rejection after surgery were recruited into this study, and 10 healthy adults were controls. The keratocytes and dendritic cells in the central graft were evaluated by laser scanning confocal microscopy, as well as epithelium cells, keratocytes, corneal endothelium cells, and corneal nerves (especially subepithelial plexus nerves).

RESULTS

Median density of subepithelial plexus nerves, keratocyte density in each layer of the stroma, and density of corneal endothelium cells were all lower in clear grafts than in controls. The dendritic cells of five (16.7%) patients were active in Bowman's membrane and stromal membrane of the graft after PK.

CONCLUSIONS

Activated dendritic cells and Langerhans cells could be detected in some of the clear grafts, which indicated that the subclinical stress of immune reaction took part in the chronic injury of the clear graft after PK, even when there was no clinical rejection episode.

Prevention and treatment of corneal graft rejection: current practice patterns of the Cornea Society (2011)

PURPOSE

To analyze current practice patterns in the prevention and treatment of corneal graft rejection for both penetrating keratoplasty (PK) and endothelial keratoplasty (EK) and to compare these patterns with previously reported practices.

METHODS

In 2011, an electronic survey was sent to 670 members of the Cornea Society worldwide addressing the routine postoperative management of corneal transplants at different time points, treatment of various manifestations of corneal graft rejection, and preferred surgical techniques.

RESULTS

A total of 204 of 670 surveys (30%) were returned and evaluated. All respondents used topical corticosteroids for routine postoperative management and treatment of endothelial graft rejection. Prednisolone was the topical steroid of choice in all clinical scenarios, similar to previous surveys from 1989 to 2004. Use of subconjunctival and systemic steroids increased for many scenarios of probable and definite graft rejection. Routine use of prednisolone decreased by approximately 10% from previous surveys, whereas difluprednate was used in 13% of high-risk eyes during the first 6 months. Dexamethasone, fluorometholone, and loteprednol use remained stable. Adjunctive topical cyclosporine use increased significantly for PK and EK. EK was the preferred technique for endothelial dysfunction, whereas PK and deep anterior lamellar keratoplasty were both used for keratoconus and anterior scars. Most respondents (75%) felt that graft rejection occurs more frequently after PK than after EK.

CONCLUSIONS

Prednisolone remains the treatment of choice for management and treatment of graft rejection; however, since the introduction of difluprednate, its use has declined slightly since the introduction of difluprednate. Despite perceived differences in rejection rates, there were no differences in prophylactic steroid treatment for PK and EK.

[Cyclosporine eye drops: A 4-year retrospective study (2009-2013)]

INTRODUCTION

The University Hospitals Paris Centre Pharmacy compounds three concentrations of cyclosporine eye drops: 20mg/mL (=2%); 5mg/mL (=0.5%) and 0.5mg/mL (=0.05%). Cyclosporine A 2% drops were developed in 1995 to prevent the rejection of high-risk cornea transplants after failure of topical steroids. The other concentrations of eye drops were developed for the treatment of various immune or inflammatory diseases of the cornea, conjunctiva and uvea. These eye drops are dispensed with a physician's prescription to hospitalized or ambulatory patients. A retrospective study over 4 years (2009-2013) was conducted to analyze the details of prescription and possible adverse events.

MATERIALS AND METHODS

Dispensations made from January 1st, 2009 through December 31st, 2013 were studied, including patient age, dose of cyclosporine and practice location of prescribing physician. We also recorded the indications for cyclosporine eye drops in a sample of ambulatory patients. The analysis of local tolerability and the effect on visual comfort was based on questionnaires sent to the patients on cyclosporine 2% over a period of 2 months.

RESULTS

Cyclosporine eye drops prescription grew continuously from 2009 through 2013 for all concentrations. In 2013, 5,859 patients were treated, among which 3,616 patients with topical cyclosporine 2%, 1,681 patients with 0.5%, and 562 patients with 0.05%. In total, this represents 62,621 eye drops. Treated patients ranged from 1 week to 100 years old. Topical 2% cyclosporine is indicated in 61% of cases to prevent high-risk corneal graft rejection. Other indications are corneal ulcer (6%), atopic keratoconjunctivitis (5%), vernal keratoconjunctivitis (5%) and herpetic keratitis (4%). Topical 0.5% cyclosporine is prescribed primarily for dry eye syndrome (20%) and to prevent rejection of high-risk corneal transplantation (11%), to treat ocular rosacea (10%), vernal keratoconjunctivitis (10%), atopic keratoconjunctivitis (8%) and Sjögren's syndrome (7%). Topical 0.05% cyclosporine is prescribed primarily for dry eye syndrome resistant to conventional treatment (47%) and Sjögren's syndrome (21%). Local tolerability of topical cyclosporine was evaluated in 388 patients. The majority of patients (63%) did not experience any adverse effects. The main side effects are redness, burning sensation and itching.

CONCLUSION

Prescription of various formulations of topical cyclosporine is current practice for surgical indications: rejection of high-risk corneal transplantation; or medical indications: vernal or atopic keratoconjunctivitis and dry eye syndrome. Further prospective randomized studies would be necessary to validate formulations, doses and indications of cyclosporine eye drops.

Immunosuppressants for the prophylaxis of corneal graft rejection after penetrating keratoplasty

BACKGROUND

Penetrating keratoplasty is a corneal transplantation procedure in which a full-thickness cornea from the host is replaced by a graft from a donor. The use of various immunosuppressants to prevent graft rejection, the most common cause of graft failure in the late postoperative period, is increasing.

OBJECTIVES

To assess the effectiveness of immunosuppressants in the prophylaxis of corneal allograft rejection after high- and normal-risk keratoplasty.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (2015, Issue 4), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to May 2015), EMBASE (January 1980 to May 2015), China National Knowledge Infrastructure (CNKI) (January 1913 to February 2015), VIP database (January 1989 to February 2015), Wanfang Data (www.wanfangdata.com) (January 1990 to February 2015), the ISRCTN registry (www.isrctn.com/editAdvancedSearch), ClinicalTrials.gov (www.clinicaltrials.gov), and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the English language databases on 18 May 2015 and the Chinese language databases on 20 February 2015.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) assessing the use of immunosuppressants in the prevention of graft rejection, irrespective of publication language.

DATA COLLECTION AND ANALYSIS

We used standard procedures expected by Cochrane. The primary outcome was clear graft survival at 12 months after penetrating keratoplasty. Secondary outcomes included graft rejection, best-corrected visual acuity, and quality of life. We defined 'high-risk keratoplasty' as repeat keratoplasty and other indications of reduced graft survival.

MAIN RESULTS

We included six studies conducted in Germany (three studies), Iran, India, and China. Three studies were conducted in people undergoing high-risk keratoplasty and investigated three different comparisons: systemic mycophenolate mofetil (MMF) versus no MMF; systemic MMF versus systemic cyclosporine A (CsA); and topical CsA versus placebo. One study compared topical tacrolimus to topical steroid in people with normal-risk keratoplasty, and two studies compared topical CsA to placebo in people experiencing graft rejection after normal-risk keratoplasty. Overall, we considered the trials to be at unclear or high risk of bias.MMF may not improve clear graft survival (risk ratio (RR) 1.06, 95% confidence interval (CI) 0.84 to 1.33, 1 RCT, 87 participants, low-quality evidence) but may reduce the risk of graft rejection (RR 0.49, 95% CI 0.22 to 1.08, 1 RCT, 87 participants, low-quality evidence) compared to no MMF. Visual acuity was not reported.In 1 study of 52 people comparing systemic MMF and systemic CsA, there were no graft failures in the first year of follow-up. Data from the longest follow-up (three years) suggest that there may be little difference in the effect of these two treatments on clear graft survival (RR 1.10, 95% CI 0.90 to 1.35, low-quality evidence). There was low-quality evidence of an increased risk of graft rejection with systemic MMF compared to systemic CsA, but with wide CIs compatible with increased risk with systemic CsA (RR 1.48, 95% CI 0.56 to 3.93, low-quality evidence). Visual acuity was not reported.One study of 84 people comparing topical CsA to placebo did not report clear graft survival at 1 year, which suggests that all grafts survived to 1 year. This study suggests that the use of topical CsA probably leads to little or no difference in graft rejection (RR 1.00, 95% CI 0.39 to 2.58, moderate-quality evidence). At one year, the mean difference (MD) between the two groups in visual acuity was 0.07 (95% CI -0.01 to 0.15, moderate-quality evidence).Topical CsA probably does not have an effect on clear graft survival in people experiencing graft rejection after normal-risk keratoplasty compared to placebo (RR 1.03, 95% CI 0.96 to 1.10, 2 RCTs, 283 participants, moderate-quality evidence). There were inconsistent findings on graft rejection, with one study reporting a reduced incidence of graft rejection in the CsA group (RR 0.35, 95% CI 0.14 to 0.87, 230 participants) but the other study reporting a higher average number of episodes of graft rejection in people treated with CsA (MD 1.30, 95% CI 0.39 to 2.21, 43 participants). Overall, we judged this to be low-quality evidence due to risk of bias and inconsistency. There was no evidence for a difference in visual acuity between the 2 groups at final follow-up (approximately 18 months, range 2 to 33 months) (MD 0.04, 95% CI -0.10 to 0.18, 1 RCT, 43 participants, low-quality evidence).In 1 study comparing topical tacrolimus to topical steroid, the graft survived in all of the 12 treated participants and 20 control participants at 6 months. Graft rejection was rare (0 out of 12 versus 2 out of 20) (RR 0.32, 95% CI 0.02 to 6.21, low-quality evidence). Visual acuity was not reported.None of the studies reported on quality of life. We identified an unpublished trial of basiliximab (Simulect) (NCT00409656), probably completed in 2005.

AUTHORS' CONCLUSIONS

Current evidence on the effect of immunosuppressants in the prevention of graft failure and rejection after high- and normal-risk keratoplasty is largely low quality because the number of trials was limited, and, in general, the trials were small and at risk of bias. Future trials should be large enough to detect important clinical effects, conducted with a view to minimising the risk of bias, and they should measure outcomes important to patients.

[Immunosuppressives to prevent rejection reactions after allogeneic corneal transplantation]

In order to prevent rejection of an allogeneic corneal transplant after perforating (high risk) keratoplasty, active agents from different classes of pharmacological substances are used, as with solid organ transplantation. In addition to glucocorticoids, antiproliferative agents, small molecule inhibitors and antibodies, those belonging to the group of macrolides with their many derivatives represent an interesting class of substances in this context. As a supplement to cyclosporin A (CSA) the most successful macrolide in transplantation medicine, animal experiments are currently being carried out to test newer macrolide derivatives, such as sanglifehrin A (SFA). This overview describes the classes of drugs and modes of action of currently administered standard medications in the clinical routine and new developments are presented.

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.

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.

Cyclosporine a 0.05% eye drops for the treatment of subepithelial infiltrates after epidemic keratoconjunctivitis

BACKGROUND

To evaluate the treatment with topical 0.05% cyclosporine A (CsA) in patients with subepithelial corneal infiltrates (SEI).

METHODS

We reviewed 16 patients (22 eyes) before and after the treatment with 0.05% CsA eye drops. All patients had been treated previously with topical corticosteroids without any improvement and also they had to stop the medication secondary to intraocular pressure elevation. The objective data recorded included best-corrected visual acuity (BCVA), evaluation of corneal subepithelial infiltrate scores (CSIS), intraocular pressure (IOP) prior to treatment and the last follow-up visit.

RESULTS

Six males (37.5%) and 10 females (62.5%), mean age of 35.2 ± 16.6 years, were included. The patients' average topical CsA use duration was 5.1 ± 3.5 months (1 - 13 months). The average follow up time of the patients was 9.2 ± 4.7 months (4 - 22 months). One patient, although he didn't have a 0 scale of SCIS, did not show up for follow up examinations after six months. The mean BCVA (logarithm of the minimum angle of resolution) before and after the treatment were 0.15 ± 0.15 and 0.07 ± 0.07 respectively, CSIS 1.68 ± 0.89 and 0.23 ± 0.53 respectively, IOP 18.50 ± 3.82 and 16.86 ± 2.76 mmHg respectively. There were statistically significant improvements in BCVA (p=0.002), reduction of CSIS (p=0.002) and reduction of IOP (p<0.001) prior to treatment and the last follow-up visit. 18 eyes (81.9%) showed clinical improvement and 4 (18.1%) had decreased SEI which did not fully disappear during the treatment period. The eyes which reached CSIS score 0 (18 eyes) were treated with CsA for 1 - 13 months; while the eyes which had clinical improvement but had not CSIS score 0 (4 eyes) were decided to discontinue of CsA treatment in last follow-up visit. There were recurrences in 2 eyes 3 months after the treatment. Patients reported reduction in the severity of symptoms after the treatment. Most of the patients reported no foreign body sensation, glare, or other side effects with topical CsA treatment. Overall, patients noted an improvement in vision and satisfaction with topical 0.05% CsA treatment.

CONCLUSIONS

Topical 0.05% CsA is a safe and effective alternative treatment in patients with SEI who do not respond to other treatment modalities or have undesired side effects from topical steroids.

Should unilateral congenital corneal opacities in Peters' anomaly be grafted?

PURPOSE

To evaluate the surgical outcomes and visual results after penetrating keratoplasty for congenital unilateral corneal opacities in Peters anomaly.

METHODS

This was a retrospective study of 14 children who underwent keratoplasty for a unilateral Peters anomaly between 1999 and 2009. All patients received a topical treatment of cyclosporine and corticosteroids. Suture ablation was performed between the first and second postoperative month and all patients had spectacle correction and amblyopia treatment. Age at time of surgery, posterior segment status evaluated by ultrasonography, axial length, preoperative intraocular pressure, fellow eye status, mean follow-up time, early and late complications, final graft outcome, refraction, and visual acuity upon the last visit were noted.

RESULTS

Mean age at the time of surgery was 9 months. Posterior segment was normal in all cases. Mean axial length was 18 mm and mean intraocular pressure was 11 mmHg. Mean follow-up was 30 months. Four children had graft rejection episodes, 2 of which responded to medication. Four underwent cataract surgery, one developed pupil deformation requiring a pupilloplasty, and 2 cases were complicated by surgical glaucoma. A total of 11 eyes (78.6%) had clear grafts at the end of the follow-up. Mean spherical equivalent was -1.5 D. Visual acuity was measurable in 3 cases and was 20/50 in one case, 20/63 in the second, and 20/2000 in the third. Concerning preverbal children, central, steady, and maintained fixation was found in 8 cases.

CONCLUSIONS

Operating on a unilateral congenital corneal opacity is a challenging decision and should be taken after explaining the need for long-term follow-up to the parents. Useful vision can be achieved and maintained after strict amblyopia therapy. A multidisciplinary ophthalmologic follow-up is necessary.

Effects of immunosuppressants after penetrating keratoplasty: meta-analysis of randomized controlled trials

AIM

To assess the effectiveness of immunosuppressants in the prophylaxis of corneal allograft rejection after high-risk keratoplasty and normal-risk keratoplasty.

METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, CNKI, VIP and reference lists of articles. Date of most recent search: 18 June, 2011. All randomised controlled trials (RCTs) assessing the use of immunosupressants in the prevention of graft rejection, irrespective of publication language. Two authors assessed trial quality and extracted data independently. Only dichotomous outcomes (clear graft survival, ratio of immune reactions and side effects) were available and were expressed as relative risk (RR) and 95% confidence intervals (CI).

RESULTS

Seven studies were included in this review. In the comparing of mycophenolate mofetil (MMF) with placebo, the results showed MMF could significantly reduce immune reactions compared with placebo (RR 1.08 95% Cl 0.95 to 1.21), but no effect on clear graft survival (RR 1.11 95% Cl 0.90 to 1.35). In clear graft survival and immune reactions, MMF and cyclosporine A (CsA) showed similar effect (RR 1.11 95% Cl 0.90 to 1.35, and RR 1.48, 95% Cl 0.56 to 3.93, respectively). Tacrolimus (FK506) and steroid showed similar effects on clear graft survival and immune reactions (RR 0.32, 95% CI 0.02 to 6.21, and RR 1.00, 95%CI 0.88 to 1.14, respectively). No drug relative side effect has been found.

CONCLUSION

MMF may reduce immune reactions in both normal-risk and high-risk rejection of penetrating keratoplasty. CsA and FK506 showed similar effects as MMF. However, due to the lack of large clinical trials, the evidence remain weak, the quality of evidences were rated as very low to moderate. Large, properly randomised, placebo-controlled, double masked trials are needed to evaluate the effect of immunosuppressants.

Cyclosporine A 1% eye drops for the treatment of subepithelial infiltrates after adenoviral keratoconjunctivitis

PURPOSE

To describe the use of cyclosporine A (CSA) 1% eye drops for the treatment of symptomatic corneal subepithelial infiltrates (SEI) occurring as a sequelae of adenoviral keratoconjunctivitis (AK) that are resistant to tapering of corticosteroid eye drops.

METHODS

This is a retrospective case series of patients seen at 2 institutions who had symptomatic corneal SEI occurring after AK that was resistant to tapering of corticosteroid eye drops and who were subsequently treated with CSA 1%. Information gathered included basic demographic information (age and sex), involved eye(s), duration of symptoms, initial best spectacle-corrected visual acuity (BSCVA), type of corticosteroid used, clinical course, and best spectacle-corrected visual acuity at the last follow-up visit.

RESULTS

Twelve eyes of 7 patients had symptomatic SEI develop after AK that were responsive to corticosteroid eye drops but were resistant to tapering. After the initiation of CSA eye drops, the corticosteroid eye drops could be tapered, and all eyes could be maintained on CSA eye drops once per day or less. Mean follow-up time was 13.0 months (range, 4-28 months).

CONCLUSIONS

CSA eye drops may be an effective corticosteroid-sparing agent for the treatment of SEI after AK. The use of CSA in this setting warrants further study.

Establishment of a murine model of chronic corneal allograft dysfunction

BACKGROUND

To establish a murine model of chronic corneal allograft dysfunction (CCAD) that permits molecular evaluation of chronic allograft dysfunction after corneal transplantation.

METHODS

C57BL/6 (allogeneic), CB6F1 (semiallogeneic) and BALB/c (syngeneic) corneal grafts were transplanted orthotopically to BALB/c recipients and to the BALB/c mice as a control group. The follow-up time was more than 100 days. Graft survival time was monitored. Corneal endothelium was examined by alizarin red and PI/Hoechst stain. CD4(+) and CD8(+) T lymphocytes were examined by immunohistochemistry. Ultra-structure changes of the grafts were examined by electron microscopy.

RESULTS

Median graft survival times were 17 days, 85.5 days, and >100 days in allogeneic, semiallogeneic, and syngeneic groups respectively. Acute rejection episodes were observed only in the allogeneic group. A large amount of CD4(+) and CD8(+) T lymphocyte infiltration was present in allografts only in the allogeneic group, and few CD4(+) and CD8(+) T lymphocytes were observed in grafts in other groups. Large amounts of apoptotic and necrotic cells could be seen in the allogeneic group. Endothelial cell density decreased, and few apoptotic cells could be detected in semiallogeneic and syngeneic groups. No apoptotic or necrotic endothelial cells were found in the control group. Ultra-structural characteristic changes mainly included fibrosis formation, endothelium atrophy, and degeneration in failed grafts among transplant groups, as determined by electron microscopy.

CONCLUSIONS

The changes in semiallogeneic and syngeneic groups after transplantation were similar to those observed during clinical study. Although differences between mouse strains and clinical situations remain to be explored, this murine model provides the basis for understanding the pathogenesis of CCAD.

Application of new ophthalmic technology in the pediatric patient

PURPOSE OF REVIEW

The present review will summarize briefly the recent advances in diagnostic tools, surgical techniques, and ophthalmic medications as they relate to the pediatric patient. The review will highlight results from studies that have investigated these new technologies and techniques.

RECENT FINDINGS

In the past several years there has been a plethora of literature on the application of new technologies and surgical techniques in children. New tools have been used for everything from gathering normative data about the pediatric eye to using the technologies to study diseases such as glaucoma and ocular tumors. Results of surgical techniques such as small-incision cataract surgery, sutureless vitrectomy, and refractive surgery are now reported with regularity in the pediatric ophthalmology literature.

SUMMARY

In the past 10 years pediatric ophthalmology has made significant advances. Technology has enabled us to qualify and quantify disease states more efficiently, and to explore new surgical techniques for disease processes that were formerly considered relatively untreatable.

Lokale Immunsuppressiva nach perforierender Keratoplastik

Topical steroids are routinely used in the postoperative treatment following penetrating keratoplasty. Due to the known side effects such as steroid-response glaucoma, cataract, and surface disorders, a broader armamentarium of topical immunomodulating drugs with comparable efficacy, better tolerance and less side effects is desirable. Cyclosporine A and FK506 eye drops are a promising alternative. A new approach involves subconjunctival drug delivering implants and locally applied antiangiogenic substances, which still have to be tested in clinical studies.

Tacrolimus immunosuppression in high-risk corneal grafts

BACKGROUND

Unlike the immune privilege enjoyed by low-risk corneal grafts, high-risk corneal grafts experience rejection rates comparable to liver and kidney transplants. Systemic immunosuppression reduces the risk of rejection in high-risk corneal grafts.

METHODS

Systemic tacrolimus, a specific T cell inhibitor, was used at a mean daily dose of 2.5 mg to immunosuppress 43 patients undergoing high-risk corneal transplantation. Immunosuppression was continued for a period of 18-24 months after the high-risk corneal graft.

RESULTS

During a mean follow-up period of 33.7 months, clarity of the graft was maintained in 65% of patients. Eight patients experienced rejection episodes while on tacrolimus, and this led to graft failure in five patients.

CONCLUSION

Tacrolimus is relatively safe and effective in reducing rejection and prolonging graft survival in patients with high-risk keratoplasty compared with other series where similar immunosuppression was not used.

Efficacy of topical cyclosporine 0.05% for prevention of cornea transplant rejection episodes

PURPOSE

To assess the incidence of immunologic corneal graft rejection episodes in a prospective case series of patients treated 4 times a day with topical cyclosporine 0.05%.

DESIGN

Prospective, single-center, institutional review board-approved study.

PARTICIPANTS

Fifty-two cornea transplant recipients considered low risk for graft rejection.

METHODS

Primary indications for transplantation were keratoconus, Fuchs' dystrophy, or nonherpetic, nonvascularized scars. Subjects completely tapered off prednisolone acetate 1% by 13 weeks after transplantation and used topical cyclosporine 0.05% 4 times a day, beginning either 1 or 10 weeks posttransplant, with use continued until 1 year posttransplant. One subgroup supplemented cyclosporine use with pulsed prednisolone acetate 1% dosing, 4 times a day for 4 days every 6 weeks. The incidence of immunologic corneal graft rejection episodes was compared with that in Fuchs' and keratoconus historical control subjects, who used topical steroids a median of 7 months after penetrating keratoplasty.

MAIN OUTCOME MEASURE

Incidence of immunologic graft rejection episodes.

RESULTS

Graft rejection episodes occurred earlier and with higher incidence in subjects using cyclosporine 0.05% compared with historical control subjects who used steroids for a longer period of time (P<0.0001). Cyclosporine subjects who pulse-dosed prednisolone had a significantly higher incidence of graft rejection compared with those who did not pulse steroids (P = 0.04).

CONCLUSION

The results suggest that 4 times daily dosing with topical cyclosporine 0.05% is not as effective as use of topical prednisolone acetate 1% for prevention of graft rejection episodes in low-risk corneal transplants, and that periodic pulsing with corticosteroids may increase the risk of rejection episodes.

Prevention and Treatment of Corneal Graft Rejection

PURPOSE

This study was designed to analyze current practice patterns in the prevention and treatment of corneal graft rejection and to compare these patterns with previously reported practices.

METHODS

In January 2004, a survey addressing the routine postoperative management of corneal transplants and the treatment of various manifestations of corneal graft rejection was sent to members of The Cornea Society.

RESULTS

Of the 396 surveys, 111 (28%) were returned and analyzed. All respondents used topical corticosteroids for routine postoperative management and treatment of endothelial graft rejection. Prednisolone, in brand or generic form, was used by 37 to 90% for routine management in various clinical scenarios and 81 to 91% for various manifestations of graft rejection at all time points; however, after 6 months, 12 to 26% used loteprednol etabonate for routine management. For routine management of high-risk grafts, 48% used topical cyclosporine in addition to prednisolone. Compared with previous surveys, the use of oral steroids significantly decreased for the routine management of high-risk corneal transplants, and the use of subconjunctival steroids decreased for the management of graft rejection.

CONCLUSIONS

Topical prednisolone remains the mainstay for the prevention and treatment of corneal graft rejection; however, the role of newer agents, loteprednol etabonate and topical cyclosporine, is expanding.

Topical cyclosporine A in severe steroid-dependent childhood phlyctenular keratoconjunctivitis

PURPOSE

To assess the efficacy of topical cyclosporine A (CsA) in children with phlyctenular keratoconjunctivitis associated with severe steroid-dependent corneal inflammation.

DESIGN

Prospective, noncomparative, interventional case series.

METHODS

patients: Children with phlyctenular keratoconjunctivitis associated with severe steroid-dependent corneal inflammation and not responding to oral antibiotics (cyclines or erythromycin). intervention: Topical CsA 2% four times daily, initially combined with topical dexamethasone for the first week. main outcome measures: Efficacy was judged by the patients (symptoms and ocular redness) and by the ophthalmologist (ocular redness and corneal inflammation). The patients were monitored for adverse effects, and cyclosporinemia was determined every 3 months.

RESULTS

We studied 11 children (13 eyes) with a mean age of 9 years (range, 4 to 15 years). Inflammation was controlled in all the eyes within 14 days. Inflammation did not recur during CsA monotherapy, during a mean follow-up of 12 +/- 8 months (range, 6 to 31 months). CsA therapy was stopped in eight patients (10 eyes) after a mean treatment duration of 13 +/- 9 months (range, 6 to 31 months), and no recurrences occurred during 10 +/- 3 months of follow-up (range, 6 to 12 months). Local tolerance of CsA was good. None of the patients had detectable CsA blood levels. CsA was withdrawn in one case after 6 months, because of generalized skin rash.

CONCLUSIONS

Long-term topical CsA 2% therapy is safe and effective in children with phlyctenular keratoconjunctivitis associated with severe steroid-dependent corneal inflammation.

Topical Cyclosporine A Inhibits Subepithelial Immune Infiltrates but Also Promotes Viral Shedding in Experimental Adenovirus Models

PURPOSE

To determine the effects of topical cyclosporine A (CsA), an immunomodulating T-cell inhibitor, on the formation of subepithelial immune corneal infiltrates (SEIs) and acute adenovirus replication in the NZW Rabbit Ad5 SEI and Ad5 replication models.

METHODS

In the Ad5 SEI model, eyes were treated topically with either 2% CsA in corn oil, 0.5% CsA in artificial tears, or their respective control vehicles 4 times daily for 14 days and then twice daily for 4 days. SEIs were graded on day 23 by masked slit-lamp examination. Using the same treatment protocol in the Ad5 replication model, rabbit eyes were cultured on days 0, 1, 3, 4, 5, 7, 9, 11, 14, 16, 18, and 21 postinoculation, and their tear film viral titers were determined on A549 cells.

RESULTS

The formation of SEIs was significantly reduced following treatment with either 2.0% or 0.5% CsA. However, 2% and 0.5% CsA significantly increased viral titers on several days, prolonged the duration of Ad5 shedding, and increased the number of Ad5-positive cultures per total during the late phase of infection (days 7-21) compared with their respective controls. The 0.5% CsA was equipotent to 2% CsA for most outcome parameters tested.

CONCLUSIONS

A role for topical CsA in the treatment of adenovirus ocular infections remains to be defined in large, randomized controlled clinical trials. During acute infection, reducing SEI formation is highly desirable, but enhancing viral replication may inadvertently serve to promote local epidemics. Future trials should address the important issues of optimized formulation and dose regimen and the possibility of prolonging virus shedding.