Radiological Findings in FXTAS
In this chapter we review the radiological and structural brain findings associated with fragile X-associated tremor/ataxia syndrome (FXTAS). We will review what is currently known about radiological signs of the disorder including both white matter lesions and mild to severe cortical loss. We will also review brain–molecular relationships in FXTAS including associations that have been observed between cortical and white matter changes and molecular variables such as CGG repeat length. Similarly, we will review relationships that have been reported between brain abnormalities and the neuropsychological phenotype in FXTAS (which includes working memory, executive functioning, and information processing deficits). Lastly, we will review recent findings on both the integrity of white matter tracts in the brain (using diffusion tensor imaging) and in vivo brain function (using functional magnetic resonance imaging) in individuals with the FX premutation with and without FXTAS. While much knowledge has been gained about the neuropathology of FXTAS, future work will focus on continuing our understanding of the developmental time course of this pathogenesis as well as searching for brain biomarkers of the disease in asymptomatic premutation carriers.
KeywordsWhite Matter Fractional Anisotropy Diffusion Tensor Imaging White Matter Integrity Cerebellar Volume
This work was partially supported by NINDS grant NS044299 [JG].
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