Diffusion abnormalities of the uncinate fasciculus in Alzheimer’s disease: diffusion tensor tract-specific analysis using a new method to measure the core of the tract

Abstract

Our results suggest that FA reflects progression of AD-related histopathological changes in the UF of the white matter and may represent a useful biological index in monitoring AD. Diffusion tensor tract-specific analysis with voxelized tract shape processing to measure the core of the tract may be a sensitive tool for evaluation of diffusion abnormalities of white matter tracts in AD.

Fractional Anisotropy–Threshold Dependence in Tract-Based Diffusion Tensor Analysis: Evaluation of the Uncinate Fasciculus in Alzheimer Disease

“…Increased diffusivity or decreased FA in the uncinate fasciculus or both are reported to reflect progression of histopathologic changes in AD and have been suggested as a useful biologic index in monitoring AD. 2,5 Although similar reports have been made for the cingulum, 5,14 it has landmark margins that can be determined anatomically or morphologically, and the selection of FA may not affect its measurement much. In contrast, the uncinate fasciculus is surrounded only by white matter and does not have landmark margins.…”

“…[1][2][3][4] Increased diffusivity and decreased fractional anisotropy (FA) in the uncinate fasciculus are reported to reflect progression of histopathologic changes in Alzheimer disease (AD), and both are suggested as useful biologic indices for monitoring AD. 2,5,6 For actual measurement of tract-based analyses, tractography of the required fiber bundle must be performed. The FA threshold must be set to create this tractography.…”

On the early diagnosis of Alzheimer's Disease from multimodal signals: A survey

“…DTI has shown to be a very potential tool in the early diagnosis of AD, because it can detect alterations that cannot be detected, for example, by conventional MRI [175]. It still presents some drawbacks, because there is still uncertainty about the best choice of diffusion parameters and about the methods to use to manage crossing fibres [59].…”

MR Tractography: A Review of Its Clinical Applications

“…Of these areas, the UF is one of the most commonly investigated. 51,52,54 The UF is the largest connection between the temporal and frontal lobes, and its traumatic disruption is known to result in severe memory impairment. In patients with AD and FTLD, the degree of damage to thisˆber tract, as estimated by DTI, is known to correlate with the severity of the disease process.…”