Altered gray matter volume, cerebral blood flow and functional connectivity in chronic stroke patients

Neurosci Lett. 2018 Jan 1:662:331-338. doi: 10.1016/j.neulet.2017.05.066. Epub 2017 Sep 15.

Abstract

It is entangled connections and intensive functional interactions between cortex and subcortical structures that enable our brain to perform delicate movement, and poses plasticity to recover from stroke. However, it is still unclear how cortical structures and functions change in well-recovered patients from subcortical infarctions in motor pathway. In order to reveal neuroplasticity underlying well-recovered stroke patients, both structural (gray matter volume, GMV) and functional reorganizations (cerebral blood flow, CBF and resting-state functional connectivity, rsFC) were investigated by using multi-modal MRI. Our results showed that well-recovered stroke patients exhibited significantly increased GMV in contralesional supplementary motor area (SMA), increased CBFs in contralesional superior frontal gyrus (SFG) and supramarginal gyrus (SMG) irrespective of GMV correction. Furthermore, our results showed increased rsFC between contralesional middle temporal gyrus (MTG) and SMG. Negative correlations between CBF increases and behavior test scores were also observed, suggesting neural mechanism underlying clinical improvement. Our results suggested that neuroplasticity after chronic stroke showed in both structural and functional levels, and correlation between CBF change and clinical test suggested possible biomarker for stroke recovery.

Keywords: Cerebral blood flow; Functional connectivity; Gray matter volume; Stroke; fMRI.

MeSH terms

  • Adult
  • Aged
  • Cerebral Cortex / diagnostic imaging
  • Cerebral Cortex / pathology
  • Cerebral Cortex / physiopathology*
  • Cerebrovascular Circulation / physiology*
  • Chronic Disease
  • Female
  • Gray Matter / diagnostic imaging
  • Gray Matter / pathology
  • Gray Matter / physiopathology*
  • Humans
  • Magnetic Resonance Imaging
  • Male
  • Middle Aged
  • Neural Pathways / diagnostic imaging
  • Neural Pathways / pathology
  • Neural Pathways / physiopathology*
  • Neuronal Plasticity / physiology
  • Recovery of Function / physiology
  • Stroke / diagnostic imaging
  • Stroke / pathology
  • Stroke / physiopathology*