Perilesional Perfusion in Chronic Stroke-Induced Aphasia and Its Response to Behavioral Treatment Interventions

Matthew Walenski; Yufen Chen; Kaitlyn A Litcofsky; David Caplan; Swathi Kiran; Brenda Rapp; Todd B Parrish; Cynthia K Thompson

doi:10.1162/nol_a_00068

Perilesional Perfusion in Chronic Stroke-Induced Aphasia and Its Response to Behavioral Treatment Interventions

Neurobiol Lang (Camb). 2022 May 11;3(2):345-363. doi: 10.1162/nol_a_00068. eCollection 2022 May.

Authors

Matthew Walenski^{1

2}, Yufen Chen^{2

3}, Kaitlyn A Litcofsky^{2

4}, David Caplan^{2

5}, Swathi Kiran^{2

6}, Brenda Rapp^{2

7}, Todd B Parrish^{2

3}, Cynthia K Thompson^{2

4

8}

Affiliations

¹ Department of Communication Sciences and Disorders, East Carolina University, Greenville, NC.
² Center for the Neurobiology of Language Recovery, Northwestern University, Evanston, IL.
³ Department of Radiology, Feinberg School of Medicine, Northwestern University, Evanston, IL.
⁴ Department of Communication Sciences and Disorders, School of Communication, Northwestern University, Evanston, IL.
⁵ Massachusetts General Hospital, Department of Neurology, Harvard Medical School, Boston, MA.
⁶ Department of Speech, Language, and Hearing, College of Health & Rehabilitation, Boston University, Boston, MA.
⁷ Department of Cognitive Science, Krieger School of Arts & Sciences, Johns Hopkins University, Baltimore, MD.
⁸ Department of Neurology, Feinberg School of Medicine, Northwestern University, Evanston, IL.

Abstract

Stroke-induced alterations in cerebral blood flow (perfusion) may contribute to functional language impairments in chronic aphasia, particularly in perilesional tissue. Abnormal perfusion in this region may also serve as a biomarker for predicting functional improvements with behavioral treatment interventions. Using pseudo-continuous arterial spin labeling in magnetic resonance imaging (MRI), we examined perfusion in chronic aphasia, in perilesional rings in the left hemisphere and their right hemisphere homologues. In the left hemisphere we found a gradient pattern of decreasing perfusion closer to the lesion. The opposite pattern was found in the right hemisphere, with significantly increased perfusion close to the lesion homologue. Perfusion was also increased in the right hemisphere lesion homologue region relative to the surrounding tissue. We next examined changes in perfusion in two groups: one group who underwent MRI scanning before and after three months of a behavioral treatment intervention that led to significant language gains, and a second group who was scanned twice at a three-month interval without a treatment intervention. For both groups, there was no difference in perfusion over time in either the left or the right hemisphere. Moreover, within the treatment group pre-treatment perfusion scores did not predict treatment response; neither did pre-treatment perfusion predict post-treatment language performance. These results indicate that perfusion is chronically abnormal in both hemispheres, but chronically abnormal perfusion did not change in response to our behavioral treatment interventions, and did not predict responsiveness to language treatment.

Keywords: MRI; aphasia; perfusion; stroke; treatment.

Grants and funding

P50 DC012283/DC/NIDCD NIH HHS/United States