Seznam |
Téma: | Functional MRI of hypercapnia data |
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Vedoucí: | prof. Dr. Ing. Jan Kybic |
Vypsáno jako: | Diplomová práce,Individuální projekt,Dobrovolná odborná práce |
Popis: | Hypercapnia is a condition of increased presence of carbon dioxide in the
blood. Normal reaction of brain to this condition is vessel dilation that will increase the blood flow in the brain in order to compensate for the decreased presence of oxygen in blood. This processes can be monitored over time using a special MRI sequence called BOLD. The BOLD sequence is sensitive to the level of oxygen in blood and increased oxygen concentration shows as increased signal in the images. Hypercapnia BOLD imaging can used to study the vasoreactivy of vessels to the fluctuating level of carbon dioxide in blood. It can be used to identify brain regions with non-standard reaction and as such to identify problematic vessels that may contain stenos or some other vascular pathology. The hypercapnia is usually induced by letting the subjects breath air with increased carbon dioxide concentrations during MRI examination. In our data, we have used several periods of controlled breatholds which is more convenient for use in clinical practice. This, however, brings additional issues in data evaluation as the patients are not always capable to dutifully follow the protocol. The aim of this thesis is to evaluate clinical data from 50+ patients obtained during one or more sessions. The brain of each patient is supposed to contain normal regions and it may contain also pathological regions. The time course of BOLD signal in each patient needs to be examined first to identify what is the normal reaction for each patient (as being close to the expected response). Subsequently, the whole brain of each patient needs to be studied to identify if there are regions with no reaction and with pathological reaction. The result of the automatic analysis of the hypercapnia fMRI data will be compared with clinical findings and the sensitivity and specificity of the automatic method and the BOLD examination will be assessed. Data and clinical findings will be supplied by University hospital in Dresden. The results will be evaluated in close collaboration with medical doctors from the hospital. The aplicant is expected to visit Dresden regularly. The applicant is expected to be fluent in English and have good programming skills in Matlab. Willingness to learn basic principles of fMRI and BOLD imaging as well as to learn the basic medical background of the problem is expected. [In collaboration with Mgr. Jan Petr, Ph.D.] |
Pokyny: | 1. Learn the principles of functional MR imaging and data processing.
2. Design and implement a method for evaluation of hypercapnia sequences, to distinguish between normal and pathological regions. 3. Experimentally evaluate the developed method on provided clinical data. |
Literatura: | -Bernstein, King, Zhou: Handbook of MRI pulse sequences. -McRobbie, Moore, Graves, Prince: MRI From picture to proton. -U. S. Yezhuvath, K. Lewis-Amezcua, R. Varghese, G. Xiao, and H. Lu, “On the assessment of cerebrovascular reactivity using hypercapnia BOLD MRI.,” NMR in biomedicine, vol. 22, no. 7, pp. 779–86, Aug. 2009. |
Realizace: | kod v Matlabu, vysledky experimentu |
Vypsáno dne: | 28.05.2018 |