الفهرس 
AnatomyOnly 14 pages are availabe for public view
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Abstract
Mitochondrial diseases constitute a complex and heterogeneous group of metabolic disorders caused by heritable abnormalities of the respiratory electron transport cascade. Although mitochondrial dysfunction manifests over a wide range of clinical expression, it most often affects muscle and brain, where dependence on oxidative energy metabolism is highest. Mitochondrial disorders frequently manifest during childhood and early adulthood.
Conventional MRI plays a major role in radiologic diagnosis of mitochondrial diseases. MRI of MD demonstrates a variety of findings that can vary during the course of the clinical disease. The most common MR features of MD are symmetric signal abnormalities in specific gray nuclei, cortical territories without a vascular distribution, formation of cysts and foci of necrosis, global cerebral and cerebellar atrophy and focal or widespread white matter T2 and FLAIR hyperintensities. Some well-described syndromes have MRI findings that can provide sensitivity for diagnosis. However, most mitochondrial diseases present with either non-specific findings or MRI images that can be completely normal.
1H MR spectroscopy proved to be a useful investigational non invasive tool for mitochondrial diseases, as it enabled detection of metabolic abnormalities even in areas of brain that appeared normal on MR images, especially when it was performed during episodes of clinical relapses or clinical exacerbation. The hallmark 1H MRS finding in MD is high lactate level in brain.
31P-MRS would become a major tool for diagnosing mitochondrial myopathies. This application is not widely used in clinic and remains a tool for expert research groups interested in muscle physiology. However, 31P-MRS is sensitive in detecting abnormalities in energy metabolism and might be taken into account in the clinical workup of patients with suspected mitochondrial myopathies.