Diffusion tensor imaging in Niemann-Pick Type C disease.

Niemann-Pick Type C disease is a homozygous recessive disorder resulting in errant intracellular cholesterol metabolism and the accumulation of intracellular unesterified cholesterol and sphingolipids. Although no current effective treatment exists for Niemann-Pick Type C disease, a number of therapies are under development in animal models. As therapies are brought into clinical trials, it will be extremely helpful to have a reliable means to track the progression of the disease and to monitor its response to therapy. In this effort, diffusion tensor imaging has been applied to investigate the white matter in a Niemann-Pick Type C patient, and the results compared to those from age-matched control subjects. Diffusion tensor imaging enables quantitative measurement of water diffusion in white matter, which is sensitive to the architecture and integrity of the tissue. Compared with control subjects, significant reductions in fractional anisotropy values were observed in regions of white matter, most prominently in the corpus callosum. The results from this case study suggest that diffusion tensor imaging may allow progression of the disease to be quantitatively measured and may be able to play a role as a surrogate marker in clinical trials.