Management Of Corneal Disease Research Articles

3D CORNEAL MORPHO-GEOMETRIC PARAMETERS IN HEALTHY PATIENTS MEASURED WITH AN OPTICAL COHERENCE TOMOGRAPHER AND A SCHEIMPFLUG TOMOGRAPHER: A COMPARATIVE STUDY

The increasing advancement of ophthalmic procedures such as refractive surgeries, phakic lens implantations, and the management of corneal diseases has emphasized the critical nature of obtaining precise measurements of morpho-geometric parameters associated with the anterior eye segment, particularly the cornea. Despite the availability of numerous devices capable of measuring these parameters, none of them can be designated as a “gold standard”, making it particularly important to objectively characterize the differences in measurement between different devices, and the potential causes that generate them. This study seeks to evaluate possible interchangeability between measurements of the same morphological parameter in human corneas taken with two distinct technologies: the Scheimpflug Sirius tomographer and the Optical Coherence Tomographer (OCT) MS-39, both manufactured by CSO Italy. Ten healthy eyes from five adult males were selected for the study. Each eye underwent three tomographic measurements, with only those passing the devices' self-diagnostic quality test being recorded. Various morpho-geometric parameters related to the anterior and posterior corneal surfaces, as well as corneal volume, were then measured and extracted according to a validated method. Subsequently, a descriptive analysis was conducted to determine the distribution and variability of the data, followed by tests for normality and statistical comparisons. The findings suggest that while some parameters, such as anterior corneal area, demonstrate agreement between the devices, others such posterior corneal area or total corneal volume do not. In conclusion, results suggest possible interchangeably for some 3D morpho-geometrical parameters, but further study using a higher sample would be needed to confirm this evidence. Keywords: Volume, Elevation Maps, Thickness, Cornea.

The Role of Rho Kinase Inhibitors in Corneal Diseases.

The cornea, as the outermost layer of the eye, plays a crucial role in vision by focusing light onto the retina. Various diseases and injuries can compromise its clarity, leading to impaired vision. This review aims to provide a thorough overview of the pharmacological properties, therapeutic potential and associated risks of Rho-associated protein kinase (ROCK) inhibitors in the management of corneal diseases. The article focuses on four key ROCK inhibitors: Y-27632, fasudil, ripasudil, and netarsudil, providing a comparative examination. Studies supporting the use of ROCK inhibitors highlight their efficacy across diverse corneal conditions. In Fuchs' endothelial corneal dystrophy, studies on the application of Y-27632, ripasudil, and netarsudil demonstrated noteworthy enhancements in corneal clarity, endothelial cell density, and visual acuity. In pseudophakic bullous keratopathy, the injection of Y-27632 together with cultured corneal endothelial cells into the anterior chamber lead to enhanced corneal endothelial cell density and improved visual acuity. Animal models simulating chemical injury to the cornea showed a reduction of neovascularization and epithelial defects after application of fasudil and in a case of iridocorneal endothelial syndrome netarsudil improved corneal edema. Addressing safety considerations, netarsudil and ripasudil, both clinically approved, exhibit adverse events such as conjunctival hyperemia, conjunctival hemorrhage, cornea verticillata, conjunctivitis, and blepharitis. Monitoring patients during treatment becomes crucial to balancing the potential therapeutic benefits with these associated risks. In conclusion, ROCK inhibitors, particularly netarsudil and ripasudil, offer promise in managing corneal diseases. The comparative analysis of their pharmacological properties and studies supporting their efficacy underscore their potential therapeutic significance. However, ongoing research is paramount to comprehensively understand their safety profiles and long-term outcomes in diverse corneal conditions, guiding their optimal application in clinical practice.

Metabolomics in Corneal Diseases: A Narrative Review from Clinical Aspects.

Corneal pathologies may have subtle manifestations in the initial stages, delaying diagnosis and timely treatment. This can lead to irreversible visual loss. Metabolomics is a rapidly developing field that allows the study of metabolites in a system, providing a complementary tool in the early diagnosis and management of corneal diseases. Early identification of biomarkers is key to prevent disease progression. The advancement of nuclear magnetic resonance and mass spectrometry allows the identification of new biomarkers in the analysis of tear, cornea, and aqueous humor. Novel perspectives on disease mechanisms are identified, which provide vital information for potential targeted therapies in the future. Current treatments are analyzed at a molecular level to offer further information regarding their efficacy. In this article, we provide a comprehensive review of the metabolomic studies undertaken in the cornea and various pathologies such as dry eye disease, Sjogren's syndrome, keratoconus, post-refractive surgery, contact lens wearers, and diabetic corneas. Lastly, we discuss the exciting future that metabolomics plays in cornea research.

Role of therapeutic contact lenses in management of corneal disease.

The current review highlights areas of innovation and research in the use of contact lenses in the treatment of corneal ectasia and ocular surface disease. A series of academic reports were published by a committee of experts reviewing evidence-based practice patterns of contact lens use. There continues to be active research in the use of contact lenses in the management of keratoconus, including mini-scleral lenses, custom impression-based scleral lenses and wavefront-guided scleral lenses. Recent reports on contact lenses for ocular surface disease were primarily reviews, retrospective case reports or case series, with publications on contact lens use in corneal epithelial defects, graft-vs.-host disease, limbal stem cell deficiency and neurotrophic keratitis. There are recent publications on advances in drug-eluting contact lenses. Corneal specialists should be aware of current advances in the field of contact lens expanding their use in corneal ectasia and ocular surface disease.

EVALUATION OF CORNEAL TOPOGRAPHIC PATTERN & DEMOGRAPHIC PROFILE WITH REFRACTIVE ERROR IN PAEDIATRIC AMETROPIA.

Aims- Evaluation of corneal topographic pattern & demographic prole with refractive error in paediatric ametropia. Material & Method- we conducted a prospective observational study in 644 eyes of 322 patients, who were presented with refractive error in tertiary centre in central India from a period of January 2018 to June 2019. They were included after taking consent from guardians. To rule out anterior segment pathology, slit lamp examination was carried out and best corrected visual acuity is recorded. Auto-refractometry and retinoscopy was performed to know refractive status of eye. Corneal topography was performed by CORNEAL TOPOGRAPHER Shin- Nippon's CT-1000 &fundus examination was rule out any posterior segment pathology. All procedures and investigation were done by the same surgeon. Result- Most common corneal topographic pattern with hypermetropia and myopia was symmetric and oval in majority of patients, whereas the pattern observed with astigmatism was symmetric and ABS-IS. Conclusion- Corneal topographic pattern might be related to the refractive status of the eye, it also helpful in observe early change and management of corneal disease.

Effectiveness of a Tele-Ophthalmology Vision Center in Treating Corneal Disorders and Its Associated Economic Benefits.

The aim of this study was to study the clinical and economic impact of a teleophthalmology-based vision center (VC) in the management of corneal diseases in rural south India. Data of patients with corneal disorders who visited the VC in the year 2019 were analyzed for the total number of outpatient visits, the proportion of corneal cases that were treated at the VC, those referred to the base hospital (BH), and the costs of treatment. In 2019, 1131 (10%) of 10,850 patients who visited the VC were diagnosed with corneal disorders. Of these, 950 (84%) patients were treated at the VC itself and did not require to be referred. The remaining 181 (16%) were referred to the BH. Of these 1131 patients, 836 (74%) patients presented with a painful acute corneal disorder. The most common painful acute corneal disorders included corneal foreign body (376, 33%), epithelial abrasions (205, 18%), and infectious keratitis (124, 11%). A patient can save approximately a minimum of INR 1200 (USD 16) by attending the VC rather than the BH. In 2019, by treating 950 patients, the VC saved approximately INR 114,0000 (USD 15,200) for the community. A similar calculation extrapolated to a 10-year period (2009-2019) revealed that by providing care for these corneal disorders at the community level, the VC saved approximately INR 705,8400 (USD 94,112) for the community. VC reduces the barriers to care by increasing the accessibility and affordability of treatment for patients with corneal disorders, resulting in a significant cost saving to the community.

The pattern of central corneal thickness in patients attending a Tertiary Hospital in Dar-Es-Salaam

Background: Central Corneal Thickness (CCT) is an indicator of corneal health status as well as being an essential tool in assessment and management of corneal diseases. It is an important factor in the diagnosis and management of glaucoma as it affects the measurement of intraocular pressure. However, the pattern of central corneal thickness in our population is not known. Our study aimed to describe the CCT measurements and their variation with age and sex among patients attending the eye clinic at Muhimbili National Hospital (MNH), in Dar es Salaam, Tanzania. Methodology: A hospital-based descriptive, cross-sectional study used convenient sampling to recruit adult patients aged 18 years and above, presenting to the MNH between August 2016 and January 2017.Visual acuity assessment, Goldman applanation tonometry and CCT assessment using an ultrasound pachymeter were performed. Patients with previous intraocular surgery were excluded. Results: A total of 398 patients (208 males and 190 females) were recruited. The mean CCT was 526.64±38.30 µm; being 523.99±38.20 µm for males and 529.7±38.3 µm for females. 226 (56.85%) had CCT of less than 520 µm.There was no statistically significant difference in CCT between gender. The proportion of patients with thinner CCT increased with increasing age from 25.8% in those < 30 years to 75% in those aged 71years and above. The mean CCT decreased with increasing age with P-value<0.001. Conclusion: The average CCT in patients attending Muhimbili National Hospital is 526.64 µm (SD 38.30) which is generally thin, inversely proportion to age and similar that of other Africans and African-Americans. This finding has implications for the management of glaucoma in this population.

Health Potential of Aloe vera against Oxidative Stress Induced Corneal Damage: An "In Vitro" Study.

Fuchs endothelial corneal dystrophy (FECD) is characterized by the gradual deterioration of corneal endothelial cells (CECs) and is the most common cause of corneal transplantation worldwide. CECs apoptosis caused by oxidative stress plays a pivotal role in the pathogenesis of FECD. Antioxidant compounds have been of considerable significance as a candidate treatment in the management of corneal diseases. Based on these findings, the objective of this study was to evaluate the effects of an aloe extract with antioxidant properties, in an “in vitro” model of FECD. Human corneal epithelial (HCE) cells were preincubated with aloe extract 100 μg/mL, two hours before hydrogen peroxide (H2O2) stimulus. H2O2 challenge significantly reduced the cell viability, increased the generation of Reactive Oxygen Species (ROS) and malondialdehyde levels. Moreover, m-RNA expression and activity of Nrf-2, Catalase and Superoxide dismutase (SOD) were reduced together with an enhanced expression of IL-1β, tumor necrosis factor-α (TNF-α), IL-6, and cyclooxygenase 2 (COX-2). Furthermore, Bcl-2, Caspase-3 and Caspase-8 expression were down-regulated while Bax was up-regulated by H2O2 stimulus. Aloe extract blunted the oxidative stress-induced inflammatory cascade triggered by H2O2 and modulated apoptosis. Aloe extract defends HCE cells from H2O2-induced injury possibly due its antioxidant and anti-inflammatory activity, indicating that eye drops containing aloe extract may be used as an adjunctive treatment for FECD.

Characterising keratometry in different dog breeds using an automatic handheld keratometer.

BackgroundKeratometry is clinically important and is routinely performed as part of human ophthalmic examination. In veterinary ophthalmology, little is known about keratometry in dogs, and its practical application has been limited. The present study aimed to describe keratometry in some dog breeds popular in Japan using a handheld keratometer.MethodsClient-owned dogs of various signalment were enrolled prospectively in the keratometry examination. Interbreed variations in mean corneal curvatures (R1R2avg) and corneal astigmatism (Δ(R1−R2)) were evaluated statistically with respect to their bodyweight based on the data which fulfilled the predetermined inclusion criteria. P<0.05 was considered statistically significant.ResultsOn examination of 237 dogs from 16 different breeds, R1R2avg (mean±sd) ranged from 7.54±0.30 mm in Pomeranians to 9.28±0.19 mm in golden retrievers. Δ(R1−R2) (mean±sd) ranged from 0.22±0.11 mm in miniature schnauzers to 0.57±0.30 mm in French bulldogs.ConclusionThe present study successfully described keratometry in 16 dog breeds. The study revealed considerable interbreed variations in both R1R2avg and Δ(R1−R2), which did not necessarily correlate with bodyweight. These results are useful both clinically in fitting contact lenses in the management of corneal diseases and non-clinically in optometric studies in dogs.

Automated segmentation of the corneal endothelium in a large set of \u2018real-world\u2019 specular microscopy images using the U-Net architecture

Monitoring the density of corneal endothelial cells (CEC) is essential in the management of corneal diseases. Its manual calculation is time consuming and prone to errors. U-Net, a neural network for biomedical image segmentation, has shown promising results in the automated segmentation of images of healthy corneas and good quality. The purpose of this study was to assess its performance in “real-world” CEC images (variable quality, different ophthalmologic diseases). The outcome measures were: precision and recall of the extraction of CEC, correctness of CEC density estimation, detection of ungradable images. A classical approach based on grayscale morphology and water shedding was pursued for comparison. There was good agreement between the automated image analysis and the manual annotation from the U-Net. R-square from Pearson’s correlation was 0.96. Recall of CEC averaged 0.34 and precision 0.84. The U-Net correctly predicted the CEC density in a large set of images of healthy and diseased corneas, including images of poor quality. It robustly ignored image regions with poor visibility of CEC. The classical approach, however, did not provide acceptable results. R-square from Pearson’s correlation with the ground truth was as low as 0.35.

A simple and non-contact optical imaging probe for evaluation of corneal diseases.

Non-contact imaging techniques are preferred in ophthalmology. Corneal disease is one of the leading causes of blindness worldwide, and a possible way of detection is by analyzing the shape and optical quality of the cornea. Here, a simple and cost-effective, non-contact optical probe system is proposed and illustrated. The probe possesses high spatial resolutions and is non-dependent on coupling medium, which are significant for a clinician and patient friendly investigation. These parameters are crucial, when considering an imaging system for the objective diagnosis and management of corneal diseases. The imaging of the cornea is performed on ex vivo porcine samples and subsequently on small laboratory animals, in vivo. The clinical significance of the proposed study is validated by performing imaging of the New Zealand white rabbit's cornea infected with Pseudomonas.

Corneal wavefront aberration measured by a rotary scanning system

Abstract Purpose Corneal wavefront aberration measurements are important in many areas such as refractive surgery, diagnosis and management of corneal disease as well as to understand the eye’s optical system. In this work the authors present the corneal anterior and posterior surface wavefront aberrations measured by an optical corneal tomographer that uses two Scheimpflug cameras attached to an innovative illumination system that allows a rotary scanning of the entire cornea. Methods The corneal wavefront aberration was computed from the corneal topographic height data of both corneal surfaces obtained by an innovative rotary scanning system. The topographic height data was computed from corneal optical sections obtained by illumination with a collimated beam expanded in a fan by a small cylindrical lens; this lens is provided with motor driven rotation in order to perform automated rotary scan of the whole cornea. This system has two stationary Scheimpflug cameras whose images are combined as if there was one virtual rotary camera synchronized with the cylindrical lens. Results After appropriate processing of the cameras images it is possible to produce true elevation maps and consequently, to compute wavefront aberrations of both corneal surfaces. In this work we present corneal aberrations measured with this system and explained how this is achieved. Conclusion This new optical system allows the measurement of corneal wavefront aberration as well as corneal thickness and 3‐D mapping of both corneal surfaces.

Applications of contact lens devices in the management of corneal disease.

Contact lens devices have a variety of therapeutic applications in the management of corneal diseases. A wide range of devices is available, some with very specific indications for use, including scleral lenses, silicone elastomer, collagen shields, large diameter corneal lenses, and silicone hydrogels. The traditional hydrogel contact lens is the most frequently used device and is indicated in at least 80% of cases. Common indications for use are relief of pain, promotion of corneal healing, mechanical protection and support, and control of corneal hydration, often a combination of effects being achieved. Visual improvement may be achieved but this is not the primary role of such devices.

Techniques for surgical correction of adnexal disease

The adnexa frequently requires the general practitioner to intervene surgically to manage underlying disease or as an ancillary aid in the management of corneal disease. Both acquired and hereditary disorders are encountered. This article reviews general anatomy and physiology of the eyelids and discusses indications for the more commonly performed surgical procedures and their execution. Procedures include tarsorrhaphy, management of eyelid lacerations, eyelid tumor resection, correction of upper and/or lower lid entropion, ectropion, a medial and lateral canthoplasty, colobomatous syndrome in the cat, management of distichiasis, trichiasis and ectopic ciliae, and reduction of a prolapse of the gland of the third eyelid. Finally a surgical pack inventory useful for adnexal surgery is described.

The Topography of Corneal Disease

This article is the seventh in a series which describes the role of computerized videokeratoscopy and highlights its value in different clinical settings. It illustrates and describes the variety of topographic patterns seen with corneal disease. Essentially, there are 3 basic mechanisms by which pathological processes can disrupt the surface topography of the cornea. These include abnormalities of the epithelium, degradation of the stroma and external compression from lid or orbital masses. With the advent of computerized videokeratoscopy, we can now easily detect and quantify such abnormalities. The mechanisms by which corneal disease effects changes in the corneal topography are illustrated and discussed. The possible clinical applications of videokeratoscopy in the management of corneal disease are reviewed.

Results of Therapeutic Penetrating Keratoplasty

To determine the anatomic and visual results of therapeutic penetrating keratoplasty (PK) and its role in the management of corneal disease. The authors reviewed the records of all of their patients who had undergone therapeutic PK over the past 9 years and evaluated each for the following criteria: cure of disease, graft clarity, and visual acuity. Patients were divided into seven categories: (1 and 2) bacterial and fungal keratitis, (3 and 4) herpetic keratitis, with and without inflammation, (5) acanthamoebic keratitis, (6) perforations due to keratoconjunctivitis sicca, and (7) other causes of perforation. In microbial keratitis, therapeutic PK eradicated the disease in all cases. Seventy-three percent of grafts for bacterial keratitis and 60% for fungal keratitis remained clear. A higher percentage of clarity was achieved when grafts were 9.0 mm or less. Seven patients with secondary endophthalmitis were cured with a surgical approach including therapeutic PK. In herpetic keratitis with active inflammation, only 36% of grafts remained clear, and inflammation recurred in 36%. All perforations due to post-herpetic persistent epithelial defects in "quiet" eyes were grafted successfully. In patients with severe keratoconjunctivitis sicca, eyes were anatomically stabilized in 83%, but all grafts failed because of complications from ocular surface disease. Therapeutic PK is valuable in the management of microbial keratitis that does not respond to antimicrobial therapy. Results are poorer for patients with herpetic keratitis, although selected patients respond to therapeutic PK when other methods of management have failed. Patients with perforations due to keratoconjunctivitis sicca have a uniformly poor prognosis for graft clarity.