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Criterial function for retinal image registration
Horáková, Pavla ; Kolář, Radim (referee) ; Harabiš, Vratislav (advisor)
This bachelor‘s thesis is focused on comparison criterial functions, which are usually used in registration of retinal images. Criterial functions reflect degree of images’ sameness thereby they influence proper registration considerably. The aim of this thesis is to discover criterial function, which is the best for image registration of retina. Registration of images is very difficult; it is important to get some informations such as an uniqueness or a shape of function.
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Detection of Diseases of Diabetes on the Human Eye Retina
Sýkorová, Tereza ; Semerád, Lukáš (referee) ; Drahanský, Martin (advisor)
This bachelor's thesis deals with the detection of the symptoms of diabetic retinopathy at retinal images taken by a digital fundus camera. Optic disc, fovea, and blood vessels are found before searching for exudates and hemorrhages. This step improves final detection. The detector uses morphological reconstruction of a candidate region for determination of specific lesions. An algorithm based on thresholding precises its edges. Found regions are classified according to shape and color. Evaluation of detection was done using 120 images selected from three databases. Adding automatic detection of signs of diabetic retinopathy into equipment for retinal screening can help medical doctors in diagnosis and prevent possible vision loss which the disease can cause.
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Automatic detection of microaneurysms in fundus images
Klímová, Markéta ; Walek, Petr (referee) ; Kolář, Radim (advisor)
Diabetic retinopathy is a serious complication of diabetes mellitus. It develops as a result of total damage of vessels caused by hyperglycemia and it is one of major causes of blindness. The microaneurysms are the first clinically observed pathologies of diabetic retinopathy. The aim of this bachelor thesis is to propose and to implement an automated microaneurysm detector. Teoretical part describes the eye anatomy, diabetic retinopathy and some existing methods of automated detection. Next the implemented solution is described and the results of the detectin are evaluated.
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Microaneurysms and hemorrhages detection in retinal images
Tobiášová, Nela ; Štohanzlová, Petra (referee) ; Kolář, Radim (advisor)
Diabetic retinopathy is a serious eye complication of diabetes mellitus and one of the major causes of blindness in the world. The microaneurysms and the haemorrhages are the pathologies of diabetic retinopathy. Their detection can halt or reverse the progression of this disease and prevent blindness. The algorithms could be helpful to ophthalmologists. This bacherol’s thesis is concerned with the detection of microaneurysms and haemorrhages in fundus images. The diabetic retinopathy, the types of lesions and the treatment methods are described in the first part of the paper. Existing methods are described as follows. The practical part of this work is aimed at the proposal and the detection of the red lesions. It consists of several steps, such as selecting the correct channel of RGB images, using local methods of contrast enhancement, edge detection, thresholding, creating a training set of the feature vector and the classification with the use of the neutral network.
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Tool for Detection and Correction of Images with Diseased Eye Retinas
Jochlík, Jakub ; Semerád, Lukáš (referee) ; Drahanský, Martin (advisor)
Loss or partial loss of eye sight can have major effect on quality of person's life. One of the most common diseases, which causes loss or partial loss of eye sight are diabetic retinopathy and age releated macular degeneration. Both of these diseases can be prevented or mediated by early detection and proper treatment. The fundus camera, which is used to capture eye retina, has had major effect on increasing quality and speed of early detection. Images captured by fundus camera can be automatically analyzed in order to detect any possible signs of retina damage. This thesis proposes one possible way of automating this process. First part of this thesis describes eye, its diseases and capturing technology. Second part then proposes way of automating detection process and its implementation. Lastly, the results are evaluated.
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Hard and soft exudates detection in retinal images
Válková, Hana ; Lamoš, Martin (referee) ; Kolář, Radim (advisor)
The thesis deals with automatic detection of soft and hard exudates in retinal images of the human eye. In its introduction the thesis describes the issue of diabetes in relation to the damage to the retina of the eye. What is described in the first place is diabetic retinopathy, its symptoms and progression of the disease. Another section is devoted to describing DIARETDB1, the freely accessible database which besides other things contains a set of images showing various degrees of disease, evaluation of images from the experts and the evaluation protocol. The next section discusses several methods for automatic detection of hard and soft exudates. The practical part of the bachelor’s thesis is aimed at image pre-processing with respect to the normalization of retinal images, the selected method for adaptive transformation of contrast was implemented. This part also containts description of chosen methology of thresholding, feature extraction based on lesions intensity and its surroundings, use of Ho Kashyap classifier is described, classification of lesions in images is followed. In conclusion realized methods is evaluated.
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Potential of stem cell therapy for diabetic retinopathy
Palacká, Kateřina ; Holáň, Vladimír (advisor) ; Tlapáková, Tereza (referee)
Diabetic retinopathy is retinal disease causing irreversible cell damage and consequently a loss of vision. Current treatment protocols have many limitations and are associated with serious site effects. A possible treatment options for retinal degenerative diseases is a use of stem cells. There are different types of stem cells. These include embryonal stem cells, induced pluripotent stem cells and cells from an adult organism, among which we can include mesenchymal stem cells (MSCs). MSCs can be found in almost all tissues of the adult organism. MSCs can migrate to the site of damage, regulate development of inflammation in retina, suppress the formation of fibrovascular scars and replace damaged cells such as nerve cells, photoreceptors and epithelial pigment cells. Application of MSCs could be a promising treatment for degenerative retinal diseases.
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Research of vitreous and vitreoretinal interface in microvascular retinal disorders focussed on eye complications of diabetes mellitus
Křížová, Libuše ; Zima, Tomáš (advisor) ; Průša, Richard (referee) ; Sosna, Tomáš (referee)
In this work I present conclusions of clinical-laboratory research focused on the patients with diabetic macular edema (DME). We performed biochemical and immunochemical analyses of vitreous samples that were collected during the pars plana vitrectomy. Moreover, at patients with non-proliferative diabetic retinopathy (NPDR) we assessed morphological characteristics of DME using optical coherence tomography (OCT). According to our findings, the vitreous and serum concentrations of uric acid and glucose were significantly higher in patients with diabetic retinopathy and DME compared to controls. Also total ratio (serum/ vitreous concentration) of uric acid and glucose was in diabetics significantly higher than in controls. The most important determinant of increasing concentration of both uric acid and glucose in the vitreous was the grade of diabetic retinopathy. Moreover, we demonstrated significant correlation between vitreous concentration of uric acid and concentration of the vascular endothelial growth factor (VEGF) in patients with DME and NPDR. We found further, that the volume of the macula (cube volume - CV) computed with the software of Cirrus HD-OCT correlates in diabetics significantly with the vitreous VEGF concentration, but not with uric acid. This OCT parameter could be used to...
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Tool for Detection and Correction of Images with Diseased Eye Retinas
Jochlík, Jakub ; Semerád, Lukáš (referee) ; Drahanský, Martin (advisor)
Loss or partial loss of eye sight can have major effect on quality of person's life. One of the most common diseases, which causes loss or partial loss of eye sight are diabetic retinopathy and age releated macular degeneration. Both of these diseases can be prevented or mediated by early detection and proper treatment. The fundus camera, which is used to capture eye retina, has had major effect on increasing quality and speed of early detection. Images captured by fundus camera can be automatically analyzed in order to detect any possible signs of retina damage. This thesis proposes one possible way of automating this process. First part of this thesis describes eye, its diseases and capturing technology. Second part then proposes way of automating detection process and its implementation. Lastly, the results are evaluated.
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Changes in eye tissues in patients with diabetes mellitus, with emphasis on the tissue surface of the eye
Česká Burdová, Marie ; Mahelková, Gabriela (advisor) ; Kalvodová, Bohdana (referee) ; Kvapil, Milan (referee)
Introduction: Relation of diabetes mellitus (DM) to the diabetic keratopathy and various stages of corneal nerve fiber damage has been well accepted. A possible association between changes in the cornea of diabetic patients and diabetic retinopathy (DR), DM duration, and age at the time of DM diagnosis were evaluated. Neuropathies are among the most common long-term complications of diabetes mellitus. Good glycemic control is essential in prevention of this complication. DM patients with similar mean glucose levels or glycated hemoglobin (HbA1c) levels often exhibit differences in evaluation of diabetic complications. One reason for these differences may be the differences in glucose variability. DM patients with similar mean glucose levels or HbA1c levels often exhibit differences in glucose variability Hypothesis: Diabetes mellitus damages the subbasal nerve fibers of the corneal and affects the density of epithelial, endothelial and stromal cells. Corneal changes in patients with DM are dependent on the degree of diabetic retinopathy (DR), age at diagnosis, duration of DM, and compensation parameters. Purpose: To compare changes in cell density in individual layers of cornea and status of subbasal nerve fibers in patients with type 1 DM (DM 1) and in healthy subjects. To evaluate the dependence...
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