Abstract #5055

Characterisation of compartmental diffusion and transverse relaxation properties of rat ischaemic tissue after stroke

Ezequiel Farrher¹, Kuan-Hung Cho², Chia-Wen Chiang³, Sheng-Min Huang⁴, Ming-Jye Chen³, Chang-Hoon Choi¹, Li-Wei Kuo^3,5, and N. Jon Shah^1,6,7,8

¹Institute of Neuroscience and Medicine 4 - Medical Imaging Physics, Forschungszentrum Jülich, Jülich, Germany, ²Department of Electronic Engineering, National United University, Miaoli, Taiwan, ³Institute of Biomedical Engineering and Nanomedicine, National Health Research Institutes, Miaoli, Taiwan, ⁴Department of Pharmacology, National Cheng Kung University, Tainan, Taiwan, ⁵Institute of Medical Device and Imaging, National Taiwan University College of Medicine, Taipei, Taiwan, ⁶Department of Neurology, Faculty of Medicine, RWTH Aachen University, Aachen, Germany, ⁷JARA – BRAIN – Translational Medicine, RWTH Aachen University, Aachen, Germany, ⁸Institute of Neuroscience and Medicine 11, Forschungszentrum Jülich, Jülich, Germany

Synopsis

Keywords: Stroke, Stroke, MCAo; ischemia; NODDI; multi-echo NODDI; transverse relaxation

Motivation: Conventional multi-echo NODDI, where the intrinsic diffusivity is fixed to a brain-wide value, has limited applicability in tissue pathologies where this parameter is significantly altered, e.g. ischaemic stroke.

Goal(s): A recently proposed estimation method for multi-echo NODDI with released intrinsic diffusivity is applied here to investigate the diffusion and relaxation properties of ischaemic tissue.

Approach: Model fitting is achieved via non-linear least-squares with an additional l₂-norm regularisation term to impose fitting stability.

Results: All compartmental diffusion and transverse relaxation parameters, in particular the tissue intrinsic diffusivity, at the ischaemic core are significantly affected compared to the contralateral side.

Impact: The application of multi-echo NODDI to investigate microstructural properties of ischaemic tissue is enabled by releasing the intrinsic diffusivity (conventionally fixed to a brain-wide value), which is greatly affected in this tissue pathology.

How to access this content:

For one year after publication, abstracts and videos are only open to registrants of this annual meeting. Registrants should use their existing login information. Non-registrant access can be purchased via the ISMRM E-Library.

After one year, current ISMRM & ISMRT members get free access to both the abstracts and videos. Non-members and non-registrants must purchase access via the ISMRM E-Library.

After two years, the meeting proceedings (abstracts) are opened to the public and require no login information. Videos remain behind password for access by members, registrants and E-Library customers.

Click here for more information on becoming a member.