Efficacy of cyanoacrylate tissue adhesive in the management of corneal thinning and perforation due to microbial keratitis

Purpose: Report the efficacy of cyanoacrylate tissue adhesive (CTA) application in the management of corneal thinning and perforations associated with microbial keratitis.Methods: A retrospective review of consecutive patients who underwent CTA application for corneal thinning and perforation secondary to microbiologically proven infectious keratitis between 2001 and 2018 at a single center. We defined successful CTA application as an intact globe without tectonic surgical intervention.Results: The cohort included 67 patients, and 37 presented with corneal perforation while 30 had corneal thinning. The perforation/thinning was central/paracentral in 43 eyes and peripheral in 23 eyes. The underlying infectious etiologies were monomicrobial in 42 cases (35 bacterial, 3 fungal, 2 viral, and 2 acanthamoeba cases) and polymicrobial in 25 cases (22 polybacterial cases and 3 cases with a combination of Gram positive bacteria and fungus). The median duration of glue retention was 29 days. The CTA success rate was 73%, 64%, and 44% at 10, 30, and 180 days, respectively. CTA application appears more successful in monomicrobial (vs. poly -microbial) and Gram positive bacterial (vs. Gram negative) keratitis but the differences are statistically nonsignificant. The location of perforation/thinning and the use of topical corticosteroid were not associated with CTA failure.Conclusion: CTA was moderately effective in restoring globe integrity in severe corneal thinning and perforation secondary to microbial keratitis in the short term. However the majority of patients require tectonic surgical intervention within 6 months. CTA application success is not significantly associated with the location of thinning/perforation or the use of topical corticosteroid

The role of Th17 immunity in chronic ocular surface disorders

Th17 cells have been implicated in the pathogenesis of numerous inflammatory and autoimmune conditions. At the ocular surface, Th17 cells have been identified as key effector cells in chronic ocular surface disease. Evidence from murine studies indicates that following differentiation and expansion, Th17 cells migrate from the lymphoid tissues to the eye, where they release inflammatory cytokines including, but not limited to, their hallmark cytokine IL-17A. As the acute phase subsides, a population of long-lived memory Th17 cells persist, which predispose hosts both to chronic inflammation and severe exacerbations of disease; of great interest is the small subset of Th17/1 cells that secrete both IL-17A and IFN-gamma in acute-on-chronic disease exacerbation. Over the past decade, substantial progress has been made in deciphering how Th17 cells interact with the immune and neuroimmune pathways that mediate chronic ocular surface disease. Here, we review (i) the evidence for Th17 immunity in chronic ocular surface disease, (ii) regulatory mechanisms that constrain the Th17 immune response, and (iii) novel therapeutic strategies targeting Th17 cells.Ophthalmic researc

Restoration of regulatory T-cell function in dry eye disease by antagonizing substance P/neurokinin-1 receptor

Substance P (SP) is a tachykinin neuropeptide, implicated in the pathogenesis of various inflammatory conditions and a critical mediator in pain transmission. Recently, the role of SP was described in the pathogenesis of dry eye disease (DED) through its role in the maturation of antigen-presenting cells at the ocular surface after exposure to desiccating stress. However, the effect of SP on regulatory T cells (Tregs), which are functionally impaired in DED, remains unclear. This study examined the phenotypic and functional changes in Tregs in response to SP in DED. The in vitro cultures of normal Tregs in the presence of SP led to a significant reduction in both Treg frequencies and their suppressive function, which was prevented by the addition of an SP receptor (neurokinin-1 receptor) antagonist. Furthermore, in vivo treatment with the neurokinin-1 receptor antagonist in DED mice effectively restored Treg function, suppressed pathogenic T helper 17 response, and significantly ameliorated the disease. Our results show that a significant increase in SP levels promotes Treg dysfunction in DED, and blockade of SP effectively restores Treg function and suppresses DED severity

Advances in the Medical Management of Neurotrophic Keratitis

Neurotrophic Keratitis (NK) is a degenerative disorder of the cornea characterized by decreased or absent sensory corneal innervation, corneal epitheliopathy and impaired healing.The clinical presentation of NK can range from persistent epithelial defects to corneal perforation and management is often both challenging and protracted. Historically, the management of NK has consisted of non-specific strategies to facilitate corneal epithelial healing such as lubrication, bandage contact lenses and tarsorrhaphy. Recent advances in the development of therapeutics for NK have provided new and efficacious targeted strategies for its management.In this article, we review recombinant human nerve growth factor (Cenegermin), currently approved for clinical use in the United States and Europe, as well as other promising therapeutic options that are in pre-clinical development such as thymosine beta 4, connexin43 inhibitors, and artificial extracellular matrix components.Ophthalmic researc

Prevalence and Risk Factors Associated With Corneal Perforation in Chronic Ocular Graft-Versus-Host-Disease

Purpose: To determine the prevalence and risk factors associated with corneal perforation in patients with chronic ocular graft-versus-host disease (oGVHD). Methods: We reviewed the case records of 405 patients diagnosed with chronic oGVHD over 8 years at a single academic center and assessed the prevalence of corneal perforation in the cohort. We reviewed patient demographics, indication for and type of hematopoietic stem cell transplantation (HSCT), time elapsed between HSCT and perforation, and clinical characteristics including oGVHD severity scores, ocular comorbidities, and topical medications at the time of perforation. Data were analyzed to determine the characteristics of patients with corneal perforation and establish the risk factors. Results: Of the 405 patients with chronic oGVHD, 15 (3.7%) developed a corneal perforation. The mean age of patients at the time of perforation was 64 +/- 11 years and 10 (67%) were men. The median time to corneal perforation was 3.3 years post-HSCT. Although perforation occurred unilaterally in all cases, 44% had epithelial defects and 38% had stromal abnormalities in the contralateral eye. Of the patients with corneal perforation, 9 (60%) had a National Institute of Health oGVHD severity score of 2 and 6 (40%) had a score of 3. Patients with chronic oGVHD on antiglaucoma drops had a significantly higher risk of corneal perforation (P < 0.001). Conclusions Corneal perforation is a rare but vision-threatening complication of chronic oGVHD. Our study emphasizes the need for frequent and long-term follow-up of patients with oGVHD regardless of the severity of disease. In particular, patients with chronic oGVHD on topical antiglaucoma medications should be monitored closely due to a higher risk for corneal perforation.Ophthalmic researc

Ocular redness - I: Etiology, pathogenesis, and assessment of conjunctival hyperemia

The translucent appearance of the conjunctiva allows for immediate visualization of changes in the circulation of the conjunctival microvasculature consisting of extensive branching of superficial and deep arterial systems and corresponding drainage pathways, and the translucent appearance of the conjunctiva allows for immediate visualization of changes in the circulation. Conjunctival hyperemia is caused by a pathological vasodilatory response of the microvasculature in response to inflammation due to a myriad of infectious and non-infectious etiologies. It is one of the most common contributors of ocular complaints that prompts visits to medical centers. Our understanding of these neurogenic and immune-mediated pathways has progressed over time and has played a critical role in developing targeted novel therapies. Due to a multitude of underlying etiologies, patients must be accurately diagnosed for efficacious management of conjunctival hyperemia. The diagnostic techniques used for the grading of conjunctival hyperemia have also evolved from descriptive and subjective grading scales to more reliable computer-based objective grading scales.Ophthalmic researc

Ocular redness-II: Progress in development of therapeutics for the management of conjunctival hyperemia

Conjunctival hyperemia is one of the most common causes for visits to primary care physicians, optometrists, ophthalmologists, and emergency rooms. Despite its high incidence, the treatment options for patients with conjunctival hyperemia are restricted to over-the-counter drugs that provide symptomatic relief due to short duration of action, tachyphylaxis and rebound redness. As our understanding of the immunopathological pathways causing conjunctival hyperemia expands, newer therapeutic targets are being discovered. These insights have also contributed to the development of animal models for mimicking the pathogenic changes in microvasculature causing hyperemia. Furthermore, this progress has catalyzed the development of novel therapeutics that provide efficacious, long-term relief from conjunctival hyperemia with minimal adverse effects.Ophthalmic researc