Longitudinal MR imaging study in the prediction of ischemic susceptibility after cerebral hypoperfusion in rats: Influence of aging and hypertension

J-T Lee; H-L Liu; J-T Yang; S-T Yang; J-R Lin; T-H Lee

doi:10.1016/j.neuroscience.2013.10.066

Longitudinal MR imaging study in the prediction of ischemic susceptibility after cerebral hypoperfusion in rats: Influence of aging and hypertension

Neuroscience. 2014 Jan 17:257:31-40. doi: 10.1016/j.neuroscience.2013.10.066. Epub 2013 Nov 2.

Authors

J-T Lee¹, H-L Liu², J-T Yang³, S-T Yang⁴, J-R Lin⁵, T-H Lee⁶

Affiliations

¹ Department of Neurology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
² Department of Medical Imaging and Radiological Sciences and Healthy Aging Research Center, Chang Gung University, Taiwan.
³ Department of Neurosurgery, Chiayi Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Taiwan.
⁴ Department of Neurosurgery, Taipei Medical University, Shuang Ho Hospital, Taiwan.
⁵ Clinical Informatics and Medical Statistics Research Center, Chang Gung University, Taiwan.
⁶ Stroke Section, Department of Neurology and Stroke Center, Chang Gung Memorial Hospital, Linkou Medical Center, Chang Gung University College of Medicine, Taiwan. Electronic address: thlee@adm.cgmh.org.tw.

PMID: 24188793
DOI: 10.1016/j.neuroscience.2013.10.066

Abstract

Our previous study has shown that aging and hypertension may alter apparent diffusion coefficient (ADC) and cerebral blood flow (CBF) and increase ischemic susceptibility in the non-ischemic rat brain. The present study wishes to further investigate whether aging and hypertension may influence cerebral diffusion/perfusion and increase ischemic susceptibility in the ischemic brain. Brain magnetic resonance (MR) imaging was examined 1day before and 1 and 7days after bilateral common carotid artery occlusion. Young and middle-aged normotensive Wistar-Kyoto rats and young and middle-aged spontaneously hypertensive rats (SHRs) were studied. Infarction occurred mainly in the parietal cortex and was larger in middle-aged SHRs than the other three groups (P<0.05). In pre-operation, ADC was higher and CBF was lower in middle-aged/hypertensive rats than young/normotensive rats (P<0.05). The ADC was higher in the parietal cortex of the rats with infarction at 7days when compared to the rats without infarction [receiver operating characteristic curve (ROC), P=0.001; binary logistic regression (BLR), P=0.006]. However, there was no difference in the hippocampus and thalamus. At day 1 post-operation, CBF reduced and ADC/CBF ratio elevated significantly in the parietal cortex of the rats with infarction when compared to the rats without infarction (CBF: ROC, P=0.002; BLR, P=0.017. ADC/CBF ratio: ROC, P=0.001; BLR, P=0.018). Our results demonstrated that pre-operation ADC and post-operation CBF and ADC/CBF ratio can be used as good MR markers in the prediction of ischemic susceptibility after cerebral hypoperfusion.

Keywords: 2-VO; ADC; ANOVA; AUC; BLR; CBF; CCA; EPI; MR; ROI; SD; SHR; WKY; Wistar-Kyoto; aging; analysis of variance; apparent diffusion coefficient; area under the curve; binary logistic regression; carotid artery; cerebral blood flow; cerebral hypoperfusion; common carotid arteries; diffusion-weighted MRI; echo-planar imaging; hypertension; magnetic resonance; perfusion-weighted MRI; region of interest; spontaneously hypertensive rat; standard deviation; two-vessel occlusion.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Aging*
Animals
Blood Pressure / physiology
Body Weight / physiology
Brain Infarction / etiology
Brain Ischemia / diagnosis*
Cerebrovascular Circulation / genetics
Cerebrovascular Circulation / physiology*
Disease Models, Animal
Disease Susceptibility*
Heart Rate / physiology
Hypertension / physiopathology*
Longitudinal Studies
Magnetic Resonance Imaging
Male
Rats
Rats, Inbred SHR
Rats, Inbred WKY