Affiliations: Department of Communication Sciences and Disorders,
University of South Carolina, Columbia, SC, USA | Department of Radiology and Radiological Science,
Medical University of South Carolina, Columbia, SC, USA | Georgia State/Georgia Tech Center for Advanced Brain
Imaging, GA, USA | Department of Neurosciences, Medical University of
South Carolina, Columbia, SC, USA
Note: [] Corresponding author: Jessica D. Richardson, Ph.D., Department
of Communication Sciences & Disorders, University of South Carolina,
Columbia, SC 29208, USA. Tel.: +1 803 777 5049; Fax: 803 777 4750; E-mail: j.d.richardson@sc.edu
Abstract: Lesion-symptom mapping studies are based upon the assumption that
behavioral impairments are directly related to structural brain damage. Given
what is known about the relationship between perfusion deficits and impairment
in acute stroke, attributing specific behavioral impairments to localized brain
damage leaves much room for speculation, as impairments could also reflect
abnormal neurovascular function in brain regions that appear structurally
intact on traditional CT and MRI scans. Compared to acute stroke, the
understanding of cerebral perfusion in chronic stroke is far less clear.
Utilizing arterial spin labeling (ASL) MRI, we examined perfusion in 17
patients with chronic left hemisphere stroke. The results revealed a decrease
in left hemisphere perfusion, primarily in peri-infarct tissue. There was also
a strong relationship between increased infarct size and decreased perfusion.
These findings have implications for lesion-symptom mapping studies as well as
research that relies on functional MRI to study chronic stroke.
