Introduction: The clinical use of magnetic resonance imaging tomographs with the magnetic field strength of 7 Tesla (T) has both advantages, such as a higher signal-to-noise ratio, increased spatial and contrast resolution and shorter acquisition times, and disadvantages, for instance: inhomogeneities of the main magnetic field (B0), inhomogeneities of the applied radiofrequency field (B1) and a higher specific absorption rate. The benefits related to 7 T magnetic resonance imaging tomographs are used worldwide to diagnose the various brain pathologies, such as multiple sclerosis (detection of cortical lesions), cerebrovascular diseases (visualisation of small intracranial vessels and submilimeter oclusive lesions), brain tumors (a more careful planning of a medical treatment and detecting brain haemorrhages) and neurodegenerative disorders (detecting changes in black substance and identifying amyloid plaques). Purpose: The purpose of the diploma work is to examine the key advantages and disadvantages of the 7 T magnetic resonance imaging scanner and further more to evaluate its importance in establishing a diagnosis of the most common brain pathologies. Methods: A descriptive method together with a systematic literature review has been used. We searched for articles in different data bases and finally included only those that fully suited the pre-set inclusion factors. Results: We found 15 appropriate articles, related to the topic of the clinical use of magnetic resonance imaging tomographs with the magnetic field strength of 7 T, which are presented in two charts. The first one lists the authors' names and the year of publication, the number of participants and the task of the research and the subject of observation, while the second one reveals the main research findings of the articles presented in the first chart. Discussion and conclusion: We figured out that the use of magnetic resonance imaging tomographs with ultra high magnetic field strengths helps to confirm a more accurate diagnosis of brain pathologies. Diagnosing the multiple sclerosis, there is a more accurate distinction between grey and white matter and lesions that are visible on SWI, FLAIR or T2-weighted images, using 7 T magnetic resonance imaging scanner. The Time-of-Flight (TOF) is an important imaging technique to visualise intracranial vessels. TOF imaging benefits from longer T1 relaxation times at ultra high fields (better contrast-to-noise ratio) and consequently, tiny intracranial vessels can be visualised (for example: lenticulostriate arteries). Magnetic resonance spectroscopy plays an important role in diagnosing brain tumors. Magnetic resonance spectroscopy at ultra high fields allowes the assesment of low concentration metabolites, such as 23Na. A higher signal-to-noise ratio and a stronger susceptibility contrast at ultra high fields enables the visualisation of tumor microvascularity on SWI images. In diagnosing neurodegenerative disorders, in Alzheimer's disease, we focus on the evaluation of the hippocampus. Using the 7 T magnetic resonance imaging scanner, there is a better contrast between grey and white matter. In Parkinson's disease, at ultra high fields, there is an increased contrast and spatial resolution, and consequently, amyloid plaques can be detected using T2* sequences.
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