Imaging Links Structural Brain Changes and Cognitive Decline in Parkinson’s

A disruption of structural connections between brain areas forming a network contributes to determine an altered information integration and organization and thus cognitive deficits in patients with Parkinson disease (PD), according to new Radiology research.

Sebastiano Galantucci, MD, of the Vita-Salute San Raffaele University in Milan, Italy, and colleagues used deterministic diffusion-tensor tractography to obtain the individual structural brain connectome of 170 patients with PD (54 with mild cognitive impairment [MCI], 116 without MCI) and 41 healthy control subjects. A network-based statistic was used to assess structural connectivity differences among groups.

The study showed that patients with PD and MCI had a large basal ganglia and frontoparietal network, with decreased fractional anisotropy (FA) in the right hemisphere and a subnetwork with an increased mean diffusivity (MD) bilaterally relative to control subjects. When compared with patients with PD without MCI, those with PD and MCI had a network with decreased FA, including basal ganglia and frontotemporoparietal regions bilaterally.

“These results provide novel information concerning the structural substrates of MCI in patients with PD and may offer markers that can be used to differentiate between patients with PD and MCI and patients with PD without MCI,” the authors write.

Web Extras

• Access the study, "Structural Brain Connectome and Cognitive Impairment in Parkinson Disease," at http://pubs.rsna.org/doi/full/10.1148/radiol.2016160274