ABSTRACT
Age-related macular degeneration (AMD) is an eye disease that can cause visual impairment and affects the elderly over 50 years of age. AMD is characterized by the presence of drusen, which causes changes in the physiological structure of the retinal pigment epithelium (RPE) and the boundaries of the Bruch's membrane layer (BM). Optical coherence tomography is one of the main exams for the detection and monitoring of AMD, which seeks changes through the evaluation of successive sectional cuts in the search for morphological changes caused by drusen. The use of CAD (Computer-Aided Detection) systems has contributed to increasing the chances of correct detection, assisting specialists in diagnosing and monitoring disease. Thus, the objective of this work is to present a method for the segmentation of the inner limiting membrane (ILM), retinal pigment epithelium, and Bruch's membrane in OCT images of healthy and Intermediate AMD patients. The method uses two deep neural networks, U-Net and DexiNed to perform the segmentation. The results were promising, reaching an average absolute error of 0.49 pixel for ILM, 0.57 for RPE, and 0.66 for BM.
Subject(s)
Macular Degeneration/diagnostic imaging , Retina/diagnostic imaging , Tomography, Optical Coherence/methods , Aged , Aged, 80 and over , Bruch Membrane/diagnostic imaging , Humans , Image Processing, Computer-Assisted/methods , Middle Aged , Retinal Pigment Epithelium/diagnostic imagingABSTRACT
Background and Objective Dry eye syndrome disease negatively impacts many people in various ways. Several tests are required to diagnose it for evaluating different physiological characteristics. One of the most applied tests for this is the manual classification of tear film images captured with Doane interferometer. Interferometry images can be categorized into five groups: debris, fine fringes, coalescing fine fringes, strong fringes, and coalescing strong fringes. Instability in the tear film creates the need for an automatic system to provide experts with diagnostic support. Therefore, the purpose of this study was to propose a method for automatic classification of the tear film lipid layer using phylogenetic diversity indexes for feature extraction and several classifiers. Methods The proposed method consisted of five main steps: (1) acquisition of VOPTICAL_GCU image dataset, (2) segmentation of the region of interest, (3) feature extraction using phylogenetic diversity indexes, (4) classification using the algorithms Support Vector Machines, Random Forest, Naive Bayes, Multilayer Perceptron, Random Tree, and RBFNetwork, and, (5) validation of results. Results The best result was obtained using Random Forest classifier, reaching an accuracy of over 97%, standard deviation of 0.51%, an area under the receiver operating characteristic curve of 0.99, a Kappa index of 0.96, and an F-Measure of 0.97. Conclusions The proposed method demonstrated that the tear film lipid layer classification problem can be resolved efficiently by using phylogenetic diversity indexes.
Subject(s)
Dry Eye Syndromes/diagnostic imaging , Interferometry , Pattern Recognition, Automated , Tears/physiology , Algorithms , Bayes Theorem , Computer Simulation , Humans , Image Processing, Computer-Assisted , Lipids/chemistry , Probability , ROC Curve , Reproducibility of Results , Scotland , Support Vector MachineABSTRACT
O glaucoma é uma das doenças que mais causam cegueira em todo o mundo. O Conselho Brasileiro de Oftalmologia (CBO) estima que no Brasil existam 985 mil portadores de glaucoma com mais de 40 anos de idade. A utilização de sistemas CAD e CADx tem contribuído para aumentar as chances de detecção e diagnósticos corretos,auxiliando os especialistas na tomada de decisões sobre o tratamento do glaucoma. OBJETIVO: Apresentar um método para diagnóstico do glaucoma em retinografias utilizando o LBP para representar a região do disco ótico, funções geoestatísticas para descrever padrões e o MVS para classificar as imagens. MÉTODOS: Executado em 3 etapas: Representação da imagem (1), Extração de Características com geoestatística (2) e Classificação e Validação (3). RESULTADOS: Foram obtidos 88% de especificidade, 82% de sensibilidade e 84% de acurácia no diagnóstico do glaucoma. CONCLUSÃO: O método mostrou-se promissor como uma forma de auxílio ao diagnóstico de glaucoma.
Glaucoma is one of the diseases that more cause blindness worldwide. The Brazilian Council of Ophthalmology (CBO) estimates that in Brazil there are 985,000 people with glaucoma over 40 years old. The use of CAD and CADxsystems has contributed to increase the chances of detection and correct diagnoses, they provide, helping specialists inmaking decisions on glaucoma treatment. OBJECTIVE: To introduce a method for diagnosing glaucoma in fundus imageusing the LBP to represent the optic disk region, geostatistical functions to describe patterns and SVM to classify the images. METHODS: Run in 3 steps: Image representation (2), Feature extraction with geostatistic (3) and Classification and Validation (4). RESULTS: we obtained 88% specificity, 82% sensitivity and 84% accuracy in the diagnosis of glaucoma. CONCLUSION: The method has shown promise as a tool to aid the diagnosis of glaucoma.