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MR imaging and MR spectroscopy of human during physical stress (MR spectroscopy imaging, MR diffusometry, MR relaxometry etc.)
Šedivý, Petr ; Hájek, Milan (advisor) ; Haberlová, Jana (referee) ; Vymazal, Josef (referee)
The dissertation is concerned to in vivo phosphorus MR spectroscopy (31 P MRS) and 1 H MR imaging (MRI) of muscle in combination with physical workload. The theoretical part of the thesis describes methodology of 31 P MRS measurement and its clinical use in research of metabolic changes in diabetes, heart failure and peripheral artery disease (PAD). The results of the thesis are divided into methodical and clinical parts. Methodical results deal with the construction of experimental equipment, software modification and development, and show of the reproducibility of the dynamic 31 P MRS. The MRI after exercise was used to the describe involvement of the individual calf muscles to muscle contraction during pedal movement in MR compatible ergometer. The first part of the clinical results of the thesis describes changes in muscle metabolism during diabetes and critical ischemia. In patients with critical ischemia the effect of treatment by angioplasty or transplantation of mesenchymal stem cells was evaluated. In the second part of the clinical results the metabolism of patients with heart failure complicated by sideropenia was studied. In these patients the effect of experimental treatment by iron carboxymaltose was described.
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Metabolic profile of human brain in vivo in MR image and spectrum
Wagnerová, Dita ; Hájek, Milan (advisor) ; Lang, Jan (referee)
Magnetic resonance imaging and spectroscopic imaging have proven to be useful to monitor a metabolism in the human brain. The thesis is concerned to repeatability and reproducibility of spectroscopic data measured on 1.5T and 3T scanners and to the development of a new method enabling the separation of pathologic and healthy tissues in patients with brain tumor using the combination of MR spectroscopic and diffusion measurements. Evaluation of repeatability and reproducibility in white matter in the parieto-occipital region, in the hippocampus and in gray matter in the frontal lobe did not show significant differences in accuracy of measurements on 1.5T and 3T scanners, but showed a significant increase of signal-to-noise ratio on 3T As a part of the thesis a program KORELACE has been developed. The program enables the evaluation of spectroscopic and diffusion data on the "pixel-by-pixel" basis in individual subjects. The existence of a statistically significant inverse correlation between the concentrations of choline and the diffusion trace values has been proven in glioblastoma, but no significant correlation has been found in a healthy tissue in volunteers. The correlation can be used to characterize borders of brain tumors and to identify the healthy tissue. Simulations confirmed the influence of...
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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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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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Treatment of spinal cord injury targetting secondary mechanisms
Valášková, Barbora ; Jendelová, Pavla (advisor) ; Hájek, Milan (referee) ; Rokyta, Richard (referee)
1 Abstract Traumatic spinal cord injury (SCI) is severe condition with devastating long- lasting consequences. There is still no available treatment. After initialing mechanical trauma, there is a huge cascade of secondary reactions which amplifies the damage. This thesis is focused on potential therapeutic effect of photobiomodulation, natural anti- inflammatory compounds epigallocatechin-3-gallate (EGCG), curcumin, their combination and extrapure synthetic form of curcumin called "nanocurcumin" on impacts of experimental model of SCI in rats. Photobiomodulation using combination of two synchronized wavelengths 808 and 905 nm improved functional recovery after SCI evaluated by battery of locomotor tests and somatosensory plantar test. The group treated by photobiomodulation obtain better results in all tests. The histopathological analysis showed a positive effect on white and gray matter sparing and our data suggests an upregulation of M2 microglia/macrophages in photobiomodulation treated rats assessed by immunohistochemical and RT-qPCR analysis. Our results demonstrated that the photobiomodulation is a promising non-invasive therapy for improving functional recovery and tissue sparing after SCI. EGCG and curcumin are natural compounds known in Chinese medicine for centuries. Their neuroprotective and...
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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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The use of MR spectroscopy in neurosurgery
Malucelli, Alberto ; Hájek, Milan (advisor) ; Ryznarová, Zuzana (referee) ; Vaverka, Miroslav (referee)
Proton MR spectroscopy is a non-invasive tool for measuring in vivo concentrations of several metabolites. The aim of this thesis was to test its applicability and reliability in neurosurgical praxis. In the first part of the study multiple MR spectroscopy methods were applied in a group of patients after surgery and oncologic treatment for high-grade glioma to test which method performed best in discriminating recurrent tumor from radionecrosis in the presence of a new enhancing lesion. The best diagnostic yield was achieved by comparison of choline, creatine and lactate between lesion and contralateral side (sensitivity 93.3%, specificity 78.6%). Creatine was significantly decreased in patients compared to controls. The inhibiting effect of ongoing oncologic treatment on cerebral and tumoral metabolism makes differential diagnosis trickier. Therefore, a diagnosis of radionecrosis assessed during ongoing radio- and chemotherapy should be confirmed after its completion. In the second part of the study MR spectroscopy data was compared with MR hippocampal volumetry and transcranial doppler examination in a cohort of patients with unilateral occlusion of the internal carotid artery. The N-acetylaspartate/choline ratio and hippocampal volume were significantly lower in both hemispheres of patients...
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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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