A Comparative White Matter Study with Parkinson′s disease,Parkinson′s Disease with Dementia and Alzheimer′s Disease

Abstract

Alzheimer's disease (AD) and Parkinson's disease (PD) are among the most common neurodegenerative disorders affecting older populations. AD is characterized by impaired memory and cognitive decline while the primary symptoms of PD include resting tremor, bradykinesia and rigidity. In PD, mild cognitive changes are frequently present, which could progress to dementia (PD dementia (PDD)). PDD and AD dementias are different in pathology although the difference in microstructural changes remains unknown. To further understand these diseases, it is essential to understand the distinct mechanism of their microstructural changes. We used diffusion tensor imaging (DTI) to investigate white matter tract differences between early stage individuals with AD (n=14), PD (n=12), PDD (n=9), and healthy non-demented controls (CON) (n=13). We used whole brain tract based spatial statistics (TBSS) and a region of interest (ROI) analysis focused on the substantia nigra (SN). We found that individuals with PDD had more widespread white matter degeneration compared to PD, AD, and CON. Individuals with AD had few regional abnormalities in the anterior and posterior projections of the corpus callosum while PD and CON did not appear to have significant white matter degeneration when compared to other groups. ROI analyses showed that PDD had the highest diffusivity in the SN and were significantly different from CON. There were no significant ROI differences between CON, PD, or AD. In conclusion, global white matter microstructural deterioration is evident in individuals with PDD, and DTI may provide a means with which to tease out pathological differences between AD and PD dementias.

Diffusion Tensor Imaging in Parkinson's Disease and Parkinsonian Syndrome: A Systematic Review

“…A few studies (25,203) using DTI in differentiation between PDD and Lewy body dementia (LBD) found generally similar regions of reduced FA in both disorders. A few other studies (51,125) comparing PDD with Alzheimer's disease suggested that PDD may exhibit greater white matter abnormalities than Alzheimer's disease, whereas Novellin et al (204) suggested the controversial findings. Due to the limited number investigations and the conflicting results, whether DTI can reliably differentiate PDD from LBD or Alzheimer's disease remains unknown.…”

A meta-analysis of diffusion tensor imaging of substantia nigra in patients with Parkinson’s disease

“…Four 11 , 13 , 17 , 19 of the studies were conducted in North America (3 in the USA, one in Canada), 6 9 , 12 , 15 – 17 , 21 , 22 in Europe (3 in the UK, 2 in Italy, 1 in Sweden), 3 10 , 14 , 18 in Asia (1 in China, 2 in Singapore), and one 20 in Australia. Eight 9 – 13 , 15 , 16 , 20 of the MRI scanners used in the studies were from Siemens, the rest 14 , 17 – 19 , 21 , 22 from Philips, Allegra, and General Electrics. The magnetic field strength index of the MRI scanners used in nine 9 , 11 , 13 – 18 , 22 of the studies was 3.0 Tesla, while the remaining five 10 , 12 , 19 – 21 studies used 1.5 Tesla.…”

“… Eddy cur. Li 14 2015 23/23 China Philips 3.0 T 8 31 manual FA √ √ Perea 17 2013 12/13 USA Allegra 3.0 T ? 36 manual none √ √ Schwarz 22 2013 32/27 UK Philips 3.0 T 8 32 manual MD √ √ Scherfler 20 2013 16/14 Austrilia Siemens 1.5 T 8 12 automatical FA, MD ?…”

Fixel-based analysis reveals fiber-specific alterations during the progression of Parkinson’s disease

“…Interestingly, alterations in CST were rarely reported in previous studies in PD patients. Studies that performed either whole-brain comparisons ( Ji et al, 2015 , Perea et al, 2013 ), fiber tracking, or region-of-interest analysis ( Lu et al, 2016 , Nilsson et al, 2007 ) failed to find CST abnormality. It is possible that the alteration in the CST was not large enough and might have been masked by crossing fibers.…”