Phase-contrast magnetic resonance imaging for the evaluation of wall shear stress in the common carotid artery of a spontaneously hypertensive rat model at 7T: Location-specific change, regional distribution along the vascular circumference, and reproducibility analysis

Shin-Lei Peng; Fu-Nien Wang; Tao-Chieh Yang; Jee-Ching Hsu; Yi-Chun Wu; Hsu-Hsia Peng

doi:10.1016/j.mri.2015.12.026

Phase-contrast magnetic resonance imaging for the evaluation of wall shear stress in the common carotid artery of a spontaneously hypertensive rat model at 7T: Location-specific change, regional distribution along the vascular circumference, and reproducibility analysis

Magn Reson Imaging. 2016 Jun;34(5):624-31. doi: 10.1016/j.mri.2015.12.026. Epub 2015 Dec 19.

Authors

Shin-Lei Peng¹, Fu-Nien Wang², Tao-Chieh Yang³, Jee-Ching Hsu⁴, Yi-Chun Wu⁵, Hsu-Hsia Peng⁶

Affiliations

¹ Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan, ROC; Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan, ROC.
² Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan, ROC.
³ Department of Neurosurgery, Taichung Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Taichung, Taiwan, ROC.
⁴ Department of Anesthesiology, Chang Gung Memorial Hospital, Chang Gung University, Taoyuan, Taiwan, ROC.
⁵ Center for Advanced Molecular Imaging and Translation, Chang Gung Memorial Hospital, Taoyuan, Taiwan, ROC.
⁶ Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan, ROC. Electronic address: hhpeng@mx.nthu.edu.tw.

PMID: 26712655
DOI: 10.1016/j.mri.2015.12.026

Abstract

Purpose: To measure wall shear stress (WSS) in the common carotid arteries (CCA) of a spontaneously hypertensive rat (SHR) model and a normotensive Wistar Kyoto rat (WKY) model by 2D phase-contrast magnetic resonance imaging (PC-MRI).

Materials and methods: PC-MRI was performed on 7 SHR and 7 WKY at ages of 4 and 7months at a 7T scanner. Images in the middle CCA (CCAmid) and in the bifurcation of CCA (CCAbifur) were acquired. The WSS values for differentiating characteristics between two models were calculated. Further, its location-specific change, regional distribution along the CCA circumference, and the reproducibility were evaluated.

Results: In the 4-month-old rats, SHR showed lower temporal averaged WSS (WSSavg) and peak systolic WSS (WSSs) in the CCAbifur in comparison with WKY (WSSavg: 0.95±0.18 vs. 1.30±0.36N/m(2) (P<0.01); WSSs: 1.68±0.70 vs. 3.22±2.49N/m(2) (P<0.05)). We observed the same trends in the 7-month-old rats. In the SHR model, the WSSavg was lower in the CCAbifur than in the CCAmid. The regional distribution of WSSavg along the circumference of CCA showed lower values in WKY, particularly in posterior segments of CCAbifur. The intra-observer, intra-scan and inter-scan reproducibility was acceptable and the disagreements were ranged from -0.05 to 0.06N/m(2).

Conclusion: This study evaluated WSS in SHR and WKY models by 2D PC-MRI. High reproducibility analyses further indicated the reliability of measurements of WSS in the CCA of SHR and WKY models using PC-MRI at 7T.

Keywords: Flow measurement; Phase-contrast magnetic resonance imaging; Spontaneously hypertensive rat; Wall shear stress.

MeSH terms

Animals
Carotid Artery, Common / diagnostic imaging*
Carotid Artery, Common / physiopathology*
Disease Models, Animal
Hypertension / physiopathology*
Magnetic Resonance Imaging / methods*
Male
Rats
Rats, Inbred SHR
Rats, Wistar
Reproducibility of Results