Event Abstract Back to Event Perilesional perfusion in chronic stroke-induced aphasia before and after behavioral treatment interventions Matthew Walenski1*, Kaitlyn Litcofsky1, Yufen Chen1, David Caplan2, Swathi Kiran3, Brenda Rapp4, Todd Parrish1 and Cynthia K. Thompson1 1 Northwestern University, United States 2 Massachusetts General Hospital, Harvard Medical School, United States 3 Boston University, United States 4 Johns Hopkins University, United States Introduction. Stroke-induced alterations in cerebral blood flow (perfusion) persist into chronic stages of aphasia, with frequent reports of perilesional hypoperfusion (Brumm et al., 2010; Richardson et al., 2011; Thompson et al., 2010, 2017). However, the relation between chronically reduced perfusion and language (dis-)function and recovery remains unclear (see Kiran and Thompson, 2019, for review). We examined perfusion in chronic aphasia in left hemisphere perilesional and homologous right hemisphere regions in treatment and no-treatment participant groups. Method. Right-handed native-English speakers with chronic aphasia induced by left hemisphere ischemic stroke were recruited from Northwestern University (agrammatism; n=17), Boston University and Massachusetts General Hospital (anomia; n=31), and Johns Hopkins University (dysgraphia; n=24) and pseudorandomly assigned to treatment (n=45) and no-treatment (n=16) groups. Perfusion was measured twice for each participant at baseline and 3-months following. Between scans, treatment group participants received language domain-specific behavioral treatment. Resting perfusion maps were collected using arterial spin labeling MRI. Raw perfusion values from each voxel were averaged across three perilesional rings in the left hemisphere (LH) and their right hemisphere (RH) homologues, from 0–6mm, 6–12mm, and 12–18mm. Mean perfusion values within each ring were normalized to the mean perfusion values of each individual’s right occipital cortex (based on the Harvard-Oxford parcellation). Results. Across all participants (n=72), LH perfusion at baseline testing was significantly lower in the 0–6mm perilesional ring relative to the 6–12mm (FDR corrected q-value = .0002) and 12–18mm rings (q=.0002); the opposite pattern was found in the right hemisphere, with significantly greater perfusion in the 0–6mm ring relative to the 6–12mm and 12–18mm rings (respectively, q=.0006, q=.0002; Figure 1a). Perfusion in the 6–12mm ring did not differ from that in the 12–18mm ring in either hemisphere (qs>.11). Perfusion was also elevated in right hemisphere regions homologous to the lesion, and was not significantly different from the 0–6mm RH ring (t(71)=.12, p=.90; Figure 1b). The abnormal perfusion in the 0–6mm rings did not correlate with baseline measures of language ability in either hemisphere (LH: r(69)=.02, p=.86; RH: r(69)=-.09, p=.44), adjusting for lesion volume. Changes in perfusion over time were not observed in the treatment or no-treatment groups in either hemisphere (all qs>.79; Table 1), despite significant language gains in the treatment group. Moreover, there was no correlation between response to treatment and difference in perfusion for any of the LH perilesional rings or their RH homologues (all qs>.11). Conclusions. These findings indicate that perfusion remains abnormal in the chronic stage of aphasia, with perilesional hypoperfusion in the ipsilesional hemisphere and hyperperfusion in homologous regions of the contralesional hemisphere. Such patterns may reflect an autoregulatory change to altered LH vasculature (Thompson et al., 2017). Importantly however, the abnormal perfusion did not correlate with baseline language deficits, and we did not observe any change in perfusion in response to our behavioral treatment interventions, despite improvement in language performance. Thus, perfusion measures may be of limited utility as biomarkers of language recovery in chronic stage stroke aphasia. Figure 1 Figure 2 Acknowledgements This work was supported by the NIH-NIDCD, Clinical Research Center Grant, P50DC012283 (PI: C. K. Thompson). The authors wish to thank Xue Wang, Elena Barbieri, Sladjana Lukic, and Brianne Dougherty for assistance with data collection and analysis. References Brumm KP, Perthen JE, Liu TT, Haist F, Ayalon L, Love T. (2010). An arterial spin labeling investigation of cerebral blood flow deficits in chronic stroke survivors. Neuroimage, 51:995–1005. doi: 10.1016/j.neuroimage.2010.03.008 Kiran, S & Thompson, CK (2019). Neuroplasticity of language networks in aphasia: Advances, Updates, and Future Challenges. Frontiers in Neuroscience, 10, a295, 1-15. doi: 10.3389/fneur.2019.00295 Richardson JD, Baker JM, Morgan PS, Rorden C, Bonilha L, Fridriksson J. (2011). Cerebral perfusion in chronic stroke: implications for lesion-symptom mapping and functional MRI. Behavioral Neurology, 24:117–22. doi: 10.1155/2011/380810 Thompson CK, den Ouden DB, Bonakdarpour B, Garibaldi K, Parrish TB. (2010). Neural plasticity and treatment-induced recovery of sentence processing in agrammatism. Neuropsychologia, 48:3211–27. doi: 10.1016/j.neuropsychologia.2010.06.036 Thompson CK, Walenski M, Chen Y, Caplan D, Kiran S, Rapp B, et al. (2017). Intrahemispheric perfusion in chronic stroke-induced aphasia. Neural Plasticity, 2017:2361691. doi: 10.1155/2017/2361691 Keywords: chronic aphasia, Stroke, Perfusion, MRI, Treatment Conference: Academy of Aphasia 57th Annual Meeting, Macau, Macao, SAR China, 27 Oct - 29 Oct, 2019. Presentation Type: Poster presentation Topic: Not eligible for student award Citation: Walenski M, Litcofsky K, Chen Y, Caplan D, Kiran S, Rapp B, Parrish T and Thompson CK (2019). Perilesional perfusion in chronic stroke-induced aphasia before and after behavioral treatment interventions. Front. Hum. Neurosci. Conference Abstract: Academy of Aphasia 57th Annual Meeting. doi: 10.3389/conf.fnhum.2019.01.00064 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 06 May 2019; Published Online: 09 Oct 2019. * Correspondence: Mx. Matthew Walenski, Northwestern University, Evanston, United States, mwalenski@gmail.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Matthew Walenski Kaitlyn Litcofsky Yufen Chen David Caplan Swathi Kiran Brenda Rapp Todd Parrish Cynthia K Thompson Google Matthew Walenski Kaitlyn Litcofsky Yufen Chen David Caplan Swathi Kiran Brenda Rapp Todd Parrish Cynthia K Thompson Google Scholar Matthew Walenski Kaitlyn Litcofsky Yufen Chen David Caplan Swathi Kiran Brenda Rapp Todd Parrish Cynthia K Thompson PubMed Matthew Walenski Kaitlyn Litcofsky Yufen Chen David Caplan Swathi Kiran Brenda Rapp Todd Parrish Cynthia K Thompson Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.