title: High b value DWI in evaluation of the hyperacute cerebral ischemia at 3T: A comparative study in an embolic canine stroke model.
abstract: Previous studies have indicated that the temporal change of relative diffusion weighted imaging (rDWI) signal intensity may help to determine the onset time of a stroke. Furthermore, several studies have indicated that high b value DWI offered improved detection rates for hyper-acute ischemic lesions compared with standard b value DWI. However, the temporal changes of the rDWI on high b value DWI remain unclear. Therefore, based on our embolic canine stroke model, we evaluated the temporal evolution of rDWI on high b value DWI, and further compared its diagnostic value in predicting the onset time of ischemic stroke with rDWI on standard b value DWI. Twelve canine MCAO models were established, and DWI was performed at 1, 2, 3, 4, 5 and 6 h after MCAO, with 3 b values of 1,000, 2,000 and 3,000. High b value DWI detected all ischemic lesions after 1 h, while standard b value did not detect the ischemic lesions in one dog at 1 h. With all three of the tested b values, rDWIs increased continuously within 6 h, while relative apparent diffusion coefficient (rADC) values rapidly decreased in 1 h, then became relatively stable. The area under the curve values for rDWI with b value of 1,000, 2,000 and 3,000, in predicting ischemic lesions within 3 h were 0.897, 0.929 and 0.938, while for rADC were 0.645, 0.583 and 0.599, respectively. Therefore, the results indicated that the rDWI was helpful in aging hyper-acute ischemic stroke, while rADC appeared not to be. High b value DWI had a higher detection rate for ischemic lesions and better predictive efficacy in determining the onset time of hyper-acute stroke.
authors.affiliation: Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China.
authors.forename: Qiguang
authors.initials: Q
authors.lastname: Cheng
authors.affiliation: Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China.
authors.forename: Xiaoquan
authors.initials: X
authors.lastname: Xu
authors.affiliation: Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China.
authors.forename: Qingquan
authors.initials: Q
authors.lastname: Zu
authors.affiliation: Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Lu
authors.affiliation: Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China.
authors.forename: Jing
authors.initials: J
authors.lastname: Yu
authors.affiliation: Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China.
authors.forename: Xinglong
authors.initials: X
authors.lastname: Liu
authors.affiliation: Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China.
authors.forename: Bin
authors.initials: B
authors.lastname: Wang
authors.affiliation: Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China.
authors.forename: Haibin
authors.initials: H
authors.lastname: Shi
authors.affiliation: Department of Radiology, Zhongda Hospital, Medical School of Southeast University, Nanjing, Jiangsu 210029, P.R. China.
authors.forename: Gaojun
authors.initials: G
authors.lastname: Teng
authors.affiliation: Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China.
authors.forename: Sheng
authors.initials: S
authors.lastname: Liu
keywords: cerebral ischemia; diffusion weighted imaging; high b value; onset time; relative signal intensity