 |
| David Vaillancourt, PhD |
A new way to track the progression of Parkinson’s disease could
help evaluate experimental treatments aimed at slowing or stopping the
disease’s progression. “We provide evidence using task-based functional MRI
(fMRI) for cortical and striatal functional deterioration in Parkinson’s
disease over a one-year period,” researchers reported in the August 16 issue of
Neurology.
Study results also describe unique patterns of functional changes
in patients with multiple system atrophy (MSA) and progressive supranuclear
palsy (PSP) that are more widespread, compared with those in Parkinson’s
disease, suggesting that distinctive rates of disease progression in
parkinsonian disorders may assist in future clinical studies of
disease-modifying therapies.
While current treatments focus on controlling symptoms,
biomarkers provide a quantifiable way to measure how medications address not
just symptoms, but the neurologic changes behind them. Previous studies have
used imaging techniques that require the injection of a drug that crosses the
blood–brain barrier. “Our technique does not rely upon the injection of a drug.
Not only is it noninvasive, it is much less expensive,” said senior study author
David Vaillancourt, PhD, a Professor in the Department of Applied Physiology
and Kinesiology at the University of Florida, Gainesville.
Dr. Vaillancourt and research colleagues used fMRI to evaluate
five areas of the brain that are key to movement and balance—the putamen,
primary motor cortex, supplementary motor area, and superior motor regions of
the cerebellum (lobules V and VI).
A total of 112 individuals were scanned at baseline and at one
year while preforming a unimanual grip force task. The study cohort included 46
patients with Parkinson’s disease, 13 patients with MSA, 19 patients with PSP,
and 34 healthy controls. The outcome measure was percent signal change in the
prespecified brain regions.
A year after the baseline study, the 46 patients with
Parkinson’s disease showed declining function in the primary motor cortex and
putamen, compared with controls. Changes after one year in patients with MSA
were exclusively extrastriatal and included a reduction in functional activity
in the primary motor cortex, supplementary motor area, and superior cerebellum.
In patients with PSP, all regions of interest were less active at one year,
compared with baseline. Functional activity of the brain regions in the control
group did not change during the study.
“Collectively, these findings point to disease-specific
noninvasive progression markers of sensorimotor brain regions in parkinsonian
disorders,” the researchers said.
The present findings build on two 2015 studies that used fMRI to
document progressive deterioration from Parkinson’s disease, MSA, and PSP.
Suggested Reading
Burciu RG, Chung JW, Shukla P, et al. Functional MRI of disease
progression in Parkinson disease and atypical parksonian syndromes. Neurology.
2016;87(7):709-717.
Burciu RG, Ofori E, Shukla P, et al. Distinct patters of brain
activity in progressive supranuclear palsy and Parkinson’s disease. Mov
Disord. 2015;30(9):1248-1258.
Oh M, Kim JS, Kim JY, et al. Subregional patterns of
preferential striatal dopamine transporter loss differ in Parkinson disease,
progressive supranuclear palsy, and multiple system atrophy. J Nucl Med.
2012;53(3):399-406.
Planetta PJ, Kurani AS, Shukla P, et al. Distinct functional and
macrostructural brain changes in Parkinson’s disease and multiple system atrophy.
Human Brain Mapp. 2015;36(3):1165-1179.
http://www.mdedge.com/neurologyreviews/article/114182/movement-disorders/functional-mri-reveals-distinct-patterns-disease
No comments:
Post a Comment