BACKGROUND AND PURPOSE: In the rim of tissue surrounding a cortical infarct, animal studies have described an increase in a number of growth-related processes that likely contribute to behavioral recovery. The current study hypothesized that in patients with good outcome after stroke, brain activation in peri-infarct tissue would be greater than normal. METHODS: In 15 patients with good recovery chronically after ischemic cortical stroke, activation within peri-infarct brain tissue was directly compared with activation within the same brain tissue of 13 control subjects. RESULTS: Although most patients did show activation within peri-infarct tissues, their activation compared with controls was reduced rather than increased. Evaluation of the T2*-weighted images underlying functional MRI mapping disclosed a significant gradient of increased T2* signal in peri-infarct tissues, likely attributable to tissue changes such as gliosis. CONCLUSIONS: Among well-recovered stroke patients, cortical activation is present in the area surrounding a cortical infarct but is smaller than normal. A baseline derangement of the T2*-weighted signal underlying functional MRI (fMRI) is also present in this area, which might influence interpretation of fMRI findings. The relationship between increased tissue T2* signal and fMRI activation is not known and requires further study.
BACKGROUND AND PURPOSE: In the rim of tissue surrounding a cortical infarct, animal studies have described an increase in a number of growth-related processes that likely contribute to behavioral recovery. The current study hypothesized that in patients with good outcome after stroke, brain activation in peri-infarct tissue would be greater than normal. METHODS: In 15 patients with good recovery chronically after ischemic cortical stroke, activation within peri-infarct brain tissue was directly compared with activation within the same brain tissue of 13 control subjects. RESULTS: Although most patients did show activation within peri-infarct tissues, their activation compared with controls was reduced rather than increased. Evaluation of the T2*-weighted images underlying functional MRI mapping disclosed a significant gradient of increased T2* signal in peri-infarct tissues, likely attributable to tissue changes such as gliosis. CONCLUSIONS: Among well-recovered strokepatients, cortical activation is present in the area surrounding a cortical infarct but is smaller than normal. A baseline derangement of the T2*-weighted signal underlying functional MRI (fMRI) is also present in this area, which might influence interpretation of fMRI findings. The relationship between increased tissue T2* signal and fMRI activation is not known and requires further study.
Authors: James C Eliassen; Erin L Boespflug; Martine Lamy; Jane Allendorfer; Wen-Jang Chu; Jerzy P Szaflarski Journal: Top Stroke Rehabil Date: 2008 Sep-Oct Impact factor: 2.119
Authors: Douglas J Cook; Cynthia Nguyen; Hyun N Chun; Irene L Llorente; Abraham S Chiu; Michal Machnicki; Thomas I Zarembinski; S Thomas Carmichael Journal: J Cereb Blood Flow Metab Date: 2016-07-20 Impact factor: 6.200
Authors: Tara L Moore; Ronald J Killiany; Monica A Pessina; Mark B Moss; Seth P Finklestein; Douglas L Rosene Journal: Neurobiol Aging Date: 2011-04-01 Impact factor: 4.673
Authors: Thomas Funck; Mohammed Al-Kuwaiti; Claude Lepage; Peter Zepper; Jeffrey Minuk; Hyman M Schipper; Alan C Evans; Alexander Thiel Journal: Hum Brain Mapp Date: 2016-09-10 Impact factor: 5.038