Imaging of neurogenetic and neurometabolic disorders of childhood

Abstract

Magnetic resonance imaging (MRI) has emerged as a powerful tool in the study of normal and abnormal brain structure, function, and biochemistry. In particular, functional MRI has come into its own as a tool to study normal and abnormal brain functions such as learning, memory, and motor learning, as well as delineation of neurogenetic cognitive phenotypes. White matter microstructure can be studied using diffusion tensor imaging, which may allow abnormal white matter to be visualized prior to abnormalities on anatomic MRI. Magnetic resonance spectroscopy, a noninvasive method to study brain biochemistry, may allow for the delineation of regional metabolic changes as a result of disease progression and/or therapeutic intervention. With MRI techniques, one can investigate the relationship between structure, function, genes, and behavior. This report discusses the research applications of MRI to the study of neurogenetic disorders of childhood.

Apparent Diffusion Coefficient Value Changes and Clinical Correlation in 90 Cases of Cytomegalovirus-Infected Fetuses with Unremarkable Fetal MRI Results

“…10,11,13,14 Diffusion-weighted imaging (DWI, DTI) was studied extensively for its utility in the evaluation of the normal development of the fetal brain. [15][16][17][18][19][20] One of the DWI metrics, the apparent diffusion coefficient, allows quantitative evaluation of cerebral maturation and intracellular changes in utero. 15,[18][19][20][21][22] Very little research has been done examining the ADC values in CMV-infected fetal brains, and even less research has focused on fetuses with normal feMRI results.…”

Expanding Role of Proton Magnetic Resonance Spectroscopy: Timely Diagnosis and Treatment Initiation in Partial Ornithine Transcarbamylase Deficiency

“…Increased lactate peak in mitochondrial diseases, reduced creatine peak in cerebral creatine deficiency syndromes, and increased N-acetyl aspartate peak in Canavan's disease have been diagnostic hallmarks for these respective disorders for decades prior to the advent of specialized genetic testing. 19 The ethos of 1H MRS lies in its ability to provide insights into the biochemistry of the central nervous system since measurement of metabolites in the plasma is seldom a true representation of their levels in the cerebrospinal fluid.…”

Neurodegenerative disorders and metabolic disease

“…Though most useful when there is a distinctive pattern that is pathognomic25 26 (table 4), neuroimaging can add to the clinical picture and biochemical findings narrowing the list of differential diagnoses.…”

“…MRS enables detection of an increasing number of brain metabolites which when used in combination with clinical and biochemical data could lead to the diagnosis of certain disorders 26. A few examples are the low creatine/phosphocreatine peak demonstrated in creatine deficiency, the lactate peak seen in mitochondrial disease, and elevated levels of N-acetylaspartate compared with choline and creatine in the diagnosis of Canavan disease.…”