首页 | 本学科首页   官方微博 | 高级检索  
     


Cerebral multifrequency MR elastography by remote excitation of intracranial shear waves
Authors:Andreas Fehlner  Sebastian Papazoglou  Matthew D. McGarry  Keith D. Paulsen  Jing Guo  Kaspar‐Josche Streitberger  Sebastian Hirsch  Jürgen Braun  Ingolf Sack
Affiliation:1. Department of Radiology, Charité – Universit?tsmedizin Berlin, Berlin, Germany;2. Thayer School of Engineering, Dartmouth College, Hanover, NH, USA;3. Institute of Medical Informatics, Charité – Universit?tsmedizin Berlin, Berlin, Germany
Abstract:The aim of this study was to introduce remote wave excitation for high‐resolution cerebral multifrequency MR elastography (mMRE). mMRE of 25–45‐Hz drive frequencies by head rocker stimulation was compared with mMRE by remote wave excitation based on a thorax mat in 12 healthy volunteers. Maps of the magnitude |G*| and phase φ of the complex shear modulus were reconstructed using multifrequency dual elasto‐visco (MDEV) inversion. After the scan, the subjects and three operators assessed the comfort and convenience of cerebral mMRE using two methods of stimulating the brain. Images were acquired in a coronal view in order to identify anatomical regions along the spinothalamic pathway. In mMRE by remote actuation, all subjects and operators appreciated an increased comfort and simplified procedural set‐up. The resulting strain amplitudes in the brain were sufficiently large to analyze using MDEV inversion, and yielded high‐resolution viscoelasticity maps which revealed specific anatomical details of brain mechanical properties: |G*| was lowest in the pons (0.97 ± 0.08 kPa) and decreased within the corticospinal tract in the caudal–cranial direction from the crus cerebri (1.64 ± 0.26 kPa) to the capsula interna (1.29 ± 0.14 kPa). By avoiding onerous mechanical stimulation of the head, remote excitation of intracranial shear waves can be used to measure viscoelastic parameters of the brain with high spatial resolution. Therewith, the new mMRE method is suitable for neuroradiological examinations in the clinic. Copyright © 2015 John Wiley & Sons, Ltd.
Keywords:MR elastography  in vivo multifrequency MRE  brain  intracranial shear strain  viscoelasticity  high resolution  corticospinal tract  pons
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号