Changes of brain structural network connection in Parkinson’s disease patients with mild cognitive dysfunction: a study based on diffusion tensor imaging

Altered structural connectome in non-lesional newly diagnosed focal epilepsy: Relation to pharmacoresistance

“…The thalamus, which has important roles in seizure initiation, propagation and modulation of focal seizures ( Blumenfeld et al, 2009 , Guye et al, 2006 , Filipescu et al, 2019 , Wykes et al, 2019 , Keller et al, 2015 , Caciagli et al, 2020 , He et al, 2020 ), may be a crucial structural hub as an imaging marker of pharamacoresistance or FBTCS. Studies in genetic generalized epilepsy have demonstrated altered thalamic connectivity ( Sinha et al, 2019 , Wang et al, 2019a , Wang et al, 2019b ), which measured shortly after diagnosis, could be related to AED treatment outcomes ( Wang et al, 2019a , Wang et al, 2019b ). Longstanding focal epilepsy with poor post-surgical outcome has been linked to altered thalamocortical connections using probabilistic tractography ( Keller et al, 2015 ) and connectomics where temporal and parietal networks have been shown to be altered in patients with persistent seizures ( Bonilha et al, 2013 ).…”

“…Q-sampling affords the advantage of identifying kissing and crossing fibers by virtue of estimating the spin distribution function directly from diffusion MRI giving a more accurate representation of the underlying biology ( Fan et al, 2016 ). Network Based Statistics (NBS, Zalesky et al, 2010 ) implements statistical methods for hypothesis-testing on human connectomes and has identified network alterations in other disorders such as depression ( Tymofiyeva et al, 2017 ), schizophrenia ( Zalesky et al, 2011 , Cocchi et al, 2014 ) and other neurodegenerative disorders ( Gou et al, 2018 , Wang et al, 2019a , Wang et al, 2019b ). NBS offers multiple-comparison corrected whole-brain connectomics with sensitive assessment of large-scale structural network alterations.…”

Effects of Subthalamic Deep Brain Stimulation With Different Frequencies in a Parkinsonian Rat Model

“…Some studies also have suggested that using DTI as a diagnostic tool to analyze changes in brain white matter fiber connections can distinguish patients with PD from the normal population (32,33). A meta-analysis included 958 patients and 764 controls in 43 clinical studies, finding that DTI could identify 226 Figure 6 DTI values of the left SN in parkinsonian rats.…”

Impaired Structural Connectivity in Parkinson's Disease Patients with Mild Cognitive Impairment: A Study Based on Probabilistic Tractography

“…Galantucci and colleagues ( 2017 ) studied structural connectivity across different brain systems and found PD-MCI to have reduced structural connectivity in networks, including the basal ganglia and fronto-parietal regions, when compared with HC and with PD patients without MCI. Wang and colleagues found decreased structural connectivity in PD-MCI patients in comparison with PD without MCI in several subnetworks, as well as reduced nodal efficiency, mostly involving orbitofrontal regions (Wang et al 2019 ).…”

“…The two studies mentioned above have used a deterministic tractography approach (Galantucci et al 2017 ; Wang et al 2019 ). However, with this approach, estimating the true trajectories of WM tracts becomes a relevant problem in the context of crossing or kissing fibers (Mori and Van Zijl 2002 ).…”