On the analysis of local and global features for hyperemia grading

In optometry, hyperemia is the accumulation of blood flow in the conjunctival tissue. Dry eye syndrome or allergic conjunctivitis are two of its main causes. Its main symptom is the presence of a red hue in the eye that optometrists evaluate according to a scale in a subjective manner. In this paper, we propose an automatic approach to the problem of hyperemia grading in the bulbar conjunctiva. We compute several image features on images of the patients' eyes, analyse the relations among them by using feature selection techniques and transform the feature vector of each image to the value in the adequate range by means of machine learning techniques. We analyse different areas of the conjunctiva to evaluate their importance for the diagnosis. Our results show that it is possible to mimic the experts' behaviour through the proposed approach.S

An Efficient Machine Learning Approach for Prediction of Conjunctiva Hyperemia Assessment using Feature Extraction Methods

The human eye is one of the most intricate sense organs. It is crucial to protect your eyes against several eye disorders that can cause vision loss if untreated in order to maintain your ability to see well. Early detection of eye diseases is therefore crucial in order to prevent any unintended consequences and control the diseases continued progression. Conjunctivitis is one such eye condition that is characterized by conjunctival inflammation, resulting in symptoms like hyperemia (redness) due to increased blood flow. With the aid of the best treatments, modern techniques, and early, precise diagnosis by professionals, it can be cured or can be greatly reduced. The proper diagnosis of the underlying cause of visual problems is frequently postponed or never carried out because of  shortage of diagnostic experts, which leads to either insufficient or postponed corrective treatment. In order to diagnose and evaluate conjunctivitis, segmentation methods are essential for locating and measuring hyperemic regions. In the present study, segmentation techniques are applied along  with feature extraction techniques to provide an effective machine learning framework for the prediction of eye problems. Using the discrete cosine transform (DCT), the segmented regions of interest are converted into feature vectors. These feature vectors are then used to train machine learning classifiers, including random forest and neural networks, which achieve a promising accuracy of 95.92%. This approach enables ophthalmologists to make more objective and accurate assessments, aiding in disease severity evaluation

A fully automated pipeline for a robust conjunctival hyperemia estimation

Purpose: Many semi-automated and fully-automated approaches have been proposed in literature to improve the objectivity of the estimation of conjunctival hyperemia, based on image processing analysis of eyes’ photographs. The purpose is to improve its evaluation using faster fully-automated systems and independent by the human subjectivity. Methods: In this work, we introduce a fully-automated analysis of the redness grading scales able to completely automatize the clinical procedure, starting from the acquired image to the redness estimation. In particular, we introduce a neural network model for the conjunctival segmentation followed by an image processing pipeline for the vessels network segmentation. From these steps, we extract some features already known in literature and whose correlation with the conjunctival redness has already been proved. Lastly, we implemented a predictive model for the conjunctival hyperemia using these features. Results: In this work, we used a dataset of images acquired during clinical practice.We trained a neural network model for the conjunctival segmentation, obtaining an average accuracy of 0.94 and a corresponding IoU score of 0.88 on a test set of images. The set of features extracted on these ROIs is able to correctly predict the Efron scale values with a Spearman’s correlation coefficient of 0.701 on a set of not previously used samples. Conclusions: The robustness of our pipeline confirms its possible usage in a clinical practice as a viable decision support system for the ophthalmologists

A Randomized, Controlled Trial of Cyclosporine A Cationic Emulsion in Pediatric Vernal Keratoconjunctivitis: The VEKTIS Study

Purpose Vernal keratoconjunctivitis (VKC) is a chronic, allergic, and potentially severe ocular disease affecting children and adolescents that can lead to impaired quality of life (QoL) and loss of vision. This study evaluated the efficacy and safety of an investigational therapy for severe VKC, cyclosporine A (CsA) cationic emulsion (CE), an oil-in-water emulsion with increased bioavailability versus conventional CsA formulations. Design The VErnal KeratoconjunctiviTIs Study (VEKTIS) is a phase 3, multicenter, double-masked, vehicle-controlled trial. Participants Pediatric patients (4 to younger than 18 years) with active severe VKC (grade of 3 or 4 on the Bonini severity scale) and severe keratitis (corneal fluorescein staining [CFS] score of 4 or 5 on the modified Oxford scale). Methods One hundred sixty-nine patients were randomized to CsA CE 0.1% (1 mg/ml) eye drops 4 times daily (high dose), CsA CE twice daily (low dose) plus vehicle twice daily, or vehicle 4 times daily for 4 months. Main Outcome Measures The primary end point was a mean composite score that reflected CFS, rescue medication use (dexamethasone 0.1% 4 times daily), and corneal ulceration over the 4 months. Results Differences in least-squares means versus vehicle for the primary end point were statistically significant for both the high-dose (0.76; P = 0.007) and the low-dose (0.67; P = 0.010) groups, with treatment effect mainly driven by CFS score. Significant differences were found between both active treatment groups and vehicle for use of rescue medication. Vernal keratoconjunctivitis symptoms and patient QoL (assessed by visual analog scale and the Quality of Life in Children with Vernal Keratoconjunctivitis questionnaire) improved in all 3 groups, with significant improvements for high-dose CsA CE versus vehicle. Conclusions The efficacy of high-dose CsA CE in improving keratitis, symptoms, and QoL for those with severe VKC was demonstrated in these study patients. In addition, in this study cohort, CsA CE was well tolerated

Mild temperature photothermal assisted anti-bacterial and anti-inflammatory nanosystem for synergistic treatment of post-cataract surgery endophthalmitis

Rationale: Endophthalmitis, which is one of the severest complications of cataract surgeries, can seriously threaten vision and even lead to irreversible blindness owing to its complicated microenvironment, including both local bacterial infection and severe inflammation. It is urgent to develop a comprehensive treatment for both anti-bacterial and anti-inflammatory effects. Methods: Herein, we developed AuAgCu2O-bromfenac sodium nanoparticles (AuAgCu2O-BS NPs), which was designed to combine anti-bacterial and anti-inflammatory effects for integrated therapy of endophthalmitis after cataract surgery. The AuAgCu2O-BS NPs could eradicate methicillin-resistant Staphylococcus aureus (MRSA) bacterial strain relied on their photodynamic effects and the release of metal ions (Ag+ and Cu+) by the hollow AuAgCu2O nanostructures mediated mild photothermal effects. The anti-inflammatory drug, bromfenac sodium, released from the nanoparticles were able to significantly reduce the local inflammation of the endophthalmitis and promote tissue rehabilitation. In vivo bacterial elimination and anti-inflammation were confirmed by a postcataract endophthalmitis rabbit model. Results: Excellent antibacterial ability of AuAgCu2O-BS NPs was verified both in vitro and in vivo. Ophthalmological clinical observation and pathologic histology analysis showed prominent treatment of inflammatory reaction. Importantly, the mild temperature photothermal effect not only promoted the release of metal ions and bromfenac sodium but also avoided the thermal damage of the surrounding tissues, which was more suitable for the practical application of ophthalmology due to the complex structure of the eyeball. Moreover, superior biocompatibility was approved by the preliminary toxicity investigations, including low cytotoxicity, negligible damage to major organs, and stable intraocular pressure. Conclusions: Our studies of nanosystem provide a promising synergic therapeutic strategy for postcataract endophthalmitis treatment with favorable prognosis and promise in clinical translations.Peer reviewe

The development and validation of a novel canine mucosal endoscopic scoring system applied to dogs with inflammatory bowel disease

Measures of disease activity are necessary when diagnosing and monitoring response to therapy in canine inflammatory bowel disease (IBD). Endoscopy has been described as the gold standard to evaluate the mucosal surface and obtain biopsies for a histopathologic diagnosis. Previous veterinary studies have failed to definitively determine the benefit of endoscopic gastrointestinal mucosal evaluation in defining disease severity in dogs with IBD. The aim of the following thesis was to evaluate the inter-observer agreement between trainee and expert endoscopists in the assessment of mucosal lesions in dogs with IBD, and to evaluate if trained operators can identify and agree upon most endoscopic lesions of mucosal inflammation using the proposed simplified endoscopic scoring index. Archived images from endoscopic procedures performed in dogs diagnosed with IBD at the Iowa State Lloyd Veterinary Medical Center from 2002-2012 were reviewed. In total, 95 images of inflammatory and normal mucosa from dogs with IBD were displayed to 3 expert and 5 trainee endoscopists (initial test). Each picture was assessed independently by the endoscopist for inflammatory changes using established indices or interpreted as normal mucosa from multiple areas of the GI tract (ie. stomach, duodenum, and colon). Agreement was measured between the trainee and expert endoscopists for each organ. The developed index was then applied to a prospective independent group of dogs (23 total) diagnosed with inflammatory bowel disease for a validation study. Comparisons were made between 2 expert endoscopists (JES & AEJ) to measure mucosal assessment agreement. Regression analysis showed a significant (p\u3c0.01) difference between expert versus trainee endoscopy scores in duodenal evaluation trial 1, although repeat duodenal lesion evaluation aided by use of a visual template improved the overall scores of trainee endoscopists to near that of expert endoscopists (p=0.06). For the validation study, the expert endoscopists had substantial to almost perfect agreement for each lesion assessed in the stomach (k\u3e0.8), had moderate to substantial agreement assessing the small intestine (k\u3e0.6-0.84) and substantial agreement when assessing the colon (k\u3e0.7-1). The conclusion is that trained operators can identify and agree upon most endoscopic lesions of mucosal inflammation

Impact of pterygium on the ocular surface and meibomian glands

To analyze how ocular surface parameters correlate to presence of pterygium and investigate the possible impact of pterygia on tear film findings and meibomian glands findings. We investigated objective parameters of the ocular surface such as conjunctival hyperemia, tear film stability and volume, meibomian gland dysfunction, dry eye disease, corneal topography comparing healthy individuals and correlating with the pterygium clinical presentation. A total of 83 patients were included. Corneal astigmatism induction was 2.65 ± 2.52 D (0.4- 11.8). The impact of pterygium on the ocular surface parameters compared to matched controls was seen in: conjunctival hyperemia (control 1.55±0.39/pterygium 2.14±0.69; p = 0.0001), tear meniscus height (control 0.24±0.05 mm/pterygium 0.36±0.14mm; p 0.0002), meiboscore lower eyelid (control 0.29±0.64/pterygium 1.38±0.95; p 0.0001) and meiboscore upper eyelid (control 0.53±0.62/pterygium 0.98±0.75; p = 0.0083). We found a high number of pterygium patients (88%) presented meibomian gland alterations. Interestingly, meibomian gland loss was coincident to the localization of the pterygium in 54% of the upper and 77% lower lids. Pterygium greatly impacts on ocular surface by inducing direct alterations in the pattern of meibomian glands besides corneal irregularities, conjunctival hyperemia and lacrimal film alterations, inducing significant symptoms and potential signs of dysfunction149FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP2014/19138-

Meibomian Gland Morphology: The Influence of Structural Variations on Gland Function and Ocular Surface Parameters

Purpose: To objectively and quantitatively characterize meibomian gland morphology and to investigate the influence of morphological variations on gland function and ocular surface and tear film parameters. Methods: One hundred fifty subjects were enrolled. The examinations included tear osmolarity, tear meniscus height, bulbar conjunctival hyperemia, noninvasive tear film breakup time, lid margin thickness, foam secretion, meibomian gland expressibility, count of functioning glands, corneal and conjunctival staining, fluorescein breakup time, lid wiper epitheliopathy, and Schirmer test. Patient symptoms were assessed using the Ocular Surface Disease Index questionnaire. Images from noncontact meibography were analyzed using an automated method that objectively estimates dropout area, number of glands, gland length and width, and gland irregularity. Results: Gland irregularity highly correlated with dropout area (r = −0.4, P < 0.001) and showed significant partial correlations with fluorescein breakup time (r = 0.162, P = 0.049) and the Ocular Surface Disease Index questionnaire (r = −0.250, P = 0.002) Subjects with dropout area <32% were divided into 2 groups: high and low irregularity. Gland expressibility was statistically significantly different between the 2 groups (U = 319.5, P = 0.006). In the high irregularity group, gland irregularity correlated with the Schirmer test (r = 0.530, P = 0.001) and corneal fluorescein staining (r = −0.377, P = 0.021). Conclusions: Automated morphological analysis of meibomian gland structure provides additional quantitative and objective information regarding gland morphology. The link between dropout area and gland function is not clear. Assessment of gland irregularity might better predict gland function and its effects on ocular surface and tear film parameters

An Evaluation of Therapeutic Noninferiority of 0.005% Latanoprost Ophthalmic Solution and Xalatan in Patients With Glaucoma or Ocular Hypertension.

PURPOSE: To assess the therapeutic noninferiority of 0.005% latanoprost ophthalmic solution versus Xalatan in the treatment of patients with primary open-angle glaucoma or ocular hypertension. PATIENTS AND METHODS: This was a double-masked, randomized, multicenter study. A total of 184 patients with a diagnosis of unilateral or bilateral primary open-angle glaucoma or ocular hypertension were randomly assigned to either 0.005% latanoprost ophthalmic solution or Xalatan for 12 weeks. The primary end-point was the change in intraocular pressure (IOP) at 12 weeks in the 2 groups. Noninferiority was reached if the 2-sided 95% confidence intervals (CI) for the difference between adjusted treatment means were entirely within the interval from -1.5 to +1.5 mm Hg. RESULTS: The difference between treatments in the change of IOP from baseline to the end of treatment was 0.12 mm Hg (95% CI: -0.47, 0.71) in the intention-to-treat population and 0 mm Hg (95% CI: -0.58, 0.57) in the per protocol population. There was no statistically significant difference between the 2 groups in terms of drug-related adverse events. The most commonly reported drug-related local adverse events were: ocular hyperemia, eyelashes growth, and eye irritation. CONCLUSIONS: This study demonstrates that 0.005% latanoprost ophthalmic solution is noninferior to Xalatan in lowering IOP and is generally well tolerate