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Analysis of value of functional neuroimaging methods in diagnostics of focal intractable epilepsy
Kudr, Martin ; Kršek, Pavel (advisor) ; Brázdil, Milan (referee) ; Hájek, Milan (referee)
Epilepsy is one of the most common neurological disorders with prevalence 0,5 to 1 %. Considerable number of patients (particularly children) suffers from intractable focal epilepsy caused by focal cortical dysplasia (FCD) - a localized malformation of cortical development. The only treatment option in these patients remains resective epilepsy surgery. Its goal is to remove the epileptogenic zone (EZ) defined as the area of the cerebral cortex that is indispensable for the generation of epileptic seizures. There is currently no exclusive diagnostic test for localizing EZ localization; the localization hypothesis is based on combination of more diagnostic methods. Neuroimaging methods (especially magnetic resonance imaging - MRI) are crucial for localizing EZ; however, functional neuroimaging methods analyzing different functional aspects of the brain tissue can be equally important. The goal of this PhD study is to analyze value of functional neuroimaging methods (especially SPECT and SISCOM respectively and FDG-PET) for the EZ localization in patients with focal intractable epilepsy. In the first presented study we analyzed value of ictal SPECT examination for the EZ localization in a large cohort of pediatric patients with FCD operated on in Miami Children's Hospital, Florida. The study proved that...
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The Parable of the Great Banquet in Luke 14:7-24
Hájek, Milan ; Brož, Jaroslav (advisor) ; Scarano, Angelo (referee)
The Parable of the Great Banquet in Luke 14:7-24 This bachelor thesis deals with the behavior of Jesus on the banquet while invited by a Pharisee. The Master communicates to present guests rules of right behavior (i.e. an objective look on one's own qualities, selfless assistance to those who are in need etc) that lead to the God's Kingdom. The way to this goal of earthly life is characterized by humility, listening to the Holy Spirit and full surrender into God's arms. God invites to Himself every human being that needs to prepare himself thoroughly by doing works of mercy. The banquet in this parable is compared to the Kingdom of God in which a man will experience the true and never lasting beatitude in contemplating God's face on the hardly describable place where no eye has seen, nor ear heard, what God had prepared for those who love Him.1 The final chapter of the work presents one of several possibilities how to apply the parable on the banquet in pastoral ministry. Keywords Banquet, the Kingdom of God, humility, mercy 1 Cf. 1 Kor 2,9.
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Correlation between in vivo quantitative MR parameters in various tissues (MR spectroscopic imaging, MR diffusometry, MR relaxometry)
Wagnerová, Dita ; Hájek, Milan (advisor) ; Krššák, Martin (referee) ; Mechl, Marek (referee)
Coregistration of MR spectroscopic (SI), diffusion (DTI), relaxation images and their subsequent correlations based on pixel-by-pixel quantitative analysis have the potential to distinguish between pathological states and healthy tissue and therefore can help assessing brain pathology extent. Patients with brain tumours and temporal lobe epilepsy (TLE) were involved in the study to validate the use of this method in clinical practice. 30 patients with a new diagnosed brain lesion, 22 patients with a treated tumour (diagnosis assessed by histology or by radiological follow-up), 20 TLE patients and 59 healthy subjects were examined on a 3T system. The measurement protocol consisted of T2-weighted MR images, SI, DTI and T2 relaxometry. Correlations were analysed with the CORIMA programme with automatic identification of pixels in the normal tissue according to control data. Brain lesions: Specific correlation patterns between metabolites, MD and T2 relaxation times (T2) were found for a given lesion localisation and tumour type. The patterns depend on different tissue states involved in the examined area. Recurrent tumours exhibited the same patterns as untreated ones but with changed parameter values caused by therapy. Metabolic values did not correlate with MD and T2 in radiation necrosis. TLE: MR...
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New Neurophysiological Indicators Measuring, Monitoring and Evaluating in Selected Psychiatric Disorders
Šóš, Peter ; Höschl, Cyril (advisor) ; Libiger, Jan (referee) ; Hájek, Milan (referee)
There is increasing amount of new knowledge in neuropsychiatric research, partially as a result of application of new neurophysiological methods of quantitative electroencephalography. This is because these techniques have good temporal resolution, are relatively non-invasive and economical. Different experimental paradigms and electroencephalographical analytical techniques are reviewed, with their potential applications in the assessment of psychiatric disorders. In the theoretical part the principles of some methods of quantitative electroencephalography, especially are described: EEG coherences, QEEG cordance and LORETA. Next chapter contains basic information about panic disorder and major depressive disorder followed by findings in functional imaging studies which are associated with the selected psychiatric disorders. Separate section is devoted to the prediction of antidepressant response. The empirical part of the thesis consists of a set of the five original papers about application of QEEG methods in a population of psychiatric patients (Bareš et al., 2010; Kopeček et al., 2008; Kopřivová et al., 2009; Šóš et al., 2008; Šóš et al., 2013). In Study 1, we followed the localization of EEG sources by means of brain electromagnetic tomography with low resolution (LORETA) in patients with panic...
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Application of Diffusion Tensor Imaging to Brain Gray and White Marker
Rulseh, Aaron Michael ; Vymazal, Josef (advisor) ; Hluštík, Petr (referee) ; Hájek, Milan (referee)
Application of Diffusion Tensor Imaging to Brain Gray and White Ma er A In the present work we explore the gray and white ma er applicability of diffusion tensor imaging (DTI). To evaluate effect of ferritin-bound iron on gray ma er contrast in DTI, we created an in vitro model consisting of agarose gel phantoms doped with ferritin, and validated our results in vivo on healthy volunteer subjects - years of age in the basal ganglia. We further explored the application of DTI to amyotrophic lateral sclerosis (ALS) and multiple system atrophy (MSA); neurodegenerative diseases with gray and white ma er pathophysiological components. In the ALS study, patients and age- and sex-matched controls were recruited, while the MSA study included probable MSA subjects ( MSA-P, MSA-C) and age- and sex-matched controls. We found that ferritin-bound iron may make a signi cant contribution to DTI scalars in gray ma er regions of the brain, mediated by eigenvalue repulsion. is has important implications for DTI studies targeting gray ma er regions, especially in adolescence and in diseases associated with altered brain-iron load. In ALS, we found altered diffusion in the corona radiata and callosal body, and changes in R in the caudate nucleus and frontal white ma er. In MSA, we observed widespread white ma er changes associated...
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31P MR Spectroscopy of Human Kidney Grafts Monitoring of MR parameters of human grafts and their comparison with clinical parameters of patients
Vyhnanovská, Pavlína ; Hájek, Milan (advisor) ; Teplan, Vladimír (referee) ; Mechl, Marek (referee)
The aim of this work was to evaluate the possibility of using in vivo phosphorus magnetic resonance spectroscopy (31P MRS) for diagnosis of kidney graft dysfunction after transplantation. In vivo 31P MRS is noninvasive imaging method which make possible to assess energy metabolism. A total of 68 patients with kidney grafts were examined on a 1.5T MR scanner. 31P MRS was performed using the 2D-chemical shift imaging method. The patients were divided into four groups: acute rejection; acute tubular necrosis; late graft dysfunction; and patients with good renal function after transplantation. We measured the signal intensities of phosphomonoesters (PME), inorganic phosphate (Pi), phosphodiesters (PDE) and -, -- adenosine triphosphate (with contribution of -, -adenosine diphosphate) and their ratios. Patients with acute rejection episodes showed significantly elevated PME/ß-ATP, PME/Pi and PDE/Pi signal ratios compared to the control group. The group with acute tubular necrosis has decreased these ratios: PDE/-ATP a PDE/Pi compared to the control group. Patients with late graft dysfunction revealed only significant decrease of PME/Pi ratio. The group of AR patients display higher ratios of PME/Pi and PDE/Pi compared to the group of ATN patients and display higher ratios of PME/Pi compared to the group of LGD....
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Diffusion Weighted Imaging and Other Quantitative MRI Methods in the Diagnostics of Selected CNS Diseases
Keller, Jiří ; Kalvach, Pavel (advisor) ; Hluštík, Petr (referee) ; Hájek, Milan (referee)
The aim of this study was to assess the scope of exploitation of the diffusion weighted imaging and other quantitative MR methods in the clinical diagnostics. We calculated the normal values of fractional an- isotropy (FA) in our group of healthy volunteers and proved FA depen- dence on age in some regions of brain using regression analysis. The relationship was quadratic in the splenium of callosal body, the left pre- central gyrus and in the pyramidal tract at the level of mesencephalon on the right. Linear decrease of FA with age was found in the rostrum of callosal body, in the white matter of frontal lobes, in the anterior limb of internal capsule on both sides and in the pyramidal tract at the level of mesencephalon on the left. In all measured parts of basal ganglia FA in- creased. Based on our data set, we propose a non-linear colour look-up table (LUT) to enhance the pathologic values. The use of this LUT is presented in patients with several neurological disorders. Quantitative methods were used also for assessment of the group of patients suffering from ALS. The changes we expected in the posterior limb of internal capsule were not significant, therefore we suppose that the presence of T2 hyperintensity in this region is not a reliable marker of the disease. T2 relaxometry detected the...
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The use of functional magnetic resonance imaging and MR tractography for neuropsychiatirc studies of cognitive functions
Ibrahim, Ibrahim ; Hájek, Milan (advisor) ; Vymazal, Josef (referee) ; Žižka, Jan (referee)
5. Summary Although conventiona! MR imaging techniques play a crucia! role in the examination of the centra!nervous system (CNS), these techniques can not give any information about functiona! properties of the brain tissue. Besides conventional MRl techniques, however, there are some MR methods enabling evaluation of these functiona! properties. These methods include functiona! magnetic resonance imaging (!MRl), diffusion-weigbted imaging (DWI) or diffusion tensor imaging (DTI), and voxel based morphometry (VBM). fMRI is a method monitoring the activity of the individua! parts of the brain duriog specific tasks and thus c1arifying their functions. fMRI has become the method of choice especia!ly in neurosurgica! procedures plarming, when it is necessary to know the relative location of the pathological lesion and to localize functiona!ly important areas of the cerebra! cortex, and thereby to reduce the risk of damage associated with the neurosurgical operations. DWI and DT[ are very important methods that may be used to assess the severity of cerebra! ischemia and the integrity ofwhite matter tracts based on diffusion properties ofthe brain tissue. Voxel·based morphometry (VBM) is an objective method and fuHy automated whole brain structura! ana! ysis. Neuropathological changes in the brain tissue of...
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Changes of the diffusion parameters of brain tissue caused by pathologic processes - the use of diffusion tensor imaging
Zolal, Amír ; Sameš, Martin (advisor) ; Hájek, Milan (referee) ; Hluštík, Petr (referee)
The thesis contains a summary of research of the changes of diffusion parameters of the white matter performed using diffusion tensor imaging (DTI). Because of the diversity of topics discussed, the text is logically divided into chapters. In the first part, the thesis contains two studies concerning the measurement of the regional changes of the diffusion parameters. The second part is dedicated to the use of the method as an instrument to explore the topographic relationships of the pyramidal tract (and other large descending tracts contained within the same space - corticopontine, corticonuclear tracts etc.). Concerning the regional changes of diffusion, the manuscript discusses two problems. One is represented by the distant changes of the pyramidal tract in the brainstem caused by a tumor adjacent to the tract in its supratentorial course, where a significant decrease of the fractional anisotropy (FA) and the increase of the tensor trace value, corresponding to mean diffusivity (MD). The second discussed problem are the artificial changes in the diffusion parameters measured after gadolinium contrast administration, that were showed to be significant even in areas outside of the postcontrast enhancement areas. The second part of the thesis most importantly confirms the accuracy of the depiction of the...
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