Leukodystrophy is a group of genetic diseases which cause progressive damage to the nervous system and eventual death, affecting the integrity of myelin sheath of nerve fibers. The myelin is the fatty layer which wraps up and isolate the nerve cell axons, which are the long processes that cluster together to make up the fibers, and these, in turn, the nerves. The most common symptoms of a leukodystrophy disease are loss in body tone, movements, gait, speech, ability to eat, vision, hearing, and behavior as there is often a slowdown in mental and physical development. Symptoms vary according to the specific type of leukodystrophy, and may be difficult to recognize in the early stages of the disease. Leukodystrophies are mostly inherited disorders, meaning that it is passed on from parent to child. They may be inherited in a recessive, dominant, or X-linked manner, depending on the type of leukodystrophy.
Each leukodystrophy has distinctive clinical, biochemical, pathologic, and radiologic features. Magnetic resonance (MR) imaging has become the primary imaging modality in patients with leukodystrophy and plays an important role in the identification, localization, and characterization of underlying white matter abnormalities in affected patients. MR imaging has also been extensively used to monitor the natural progression of various white matter disorders and the response to therapy. Although the MR imaging features of leukodystrophy are often nonspecific, systematic analysis of the finer details of disease involvement may permit a narrower differential diagnosis, which the clinician can then further refine with knowledge of patient history, clinical testing, and metabolic analysis.