Noise Reduction in Diffusion Tensor Imaging – Reducing Systematic Anisotropy Errors
نویسندگان
چکیده
Introduction Diffusion tensor imaging (DTI) allows the investigation of diffusion differences between structures in vivo. For example, measurements of diffusion anisotropy delineate fibre tracts in the white matter of normal individuals and provide a means for investigating disruptions, such as those caused by multiple sclerosis or stroke. However, DTI measurements are sensitive to noise levels, with measurements of diffusion anisotropy, such as fractional anisotropy (FA) being especially sensitive [1-3]. At low levels of signal to noise, calculations of anisotropy are subject to systematic errors, with tissues with true low values of anisotropy showing erroneously large apparent values.
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