Meeting Banner
Abstract #3913

Local EPI Distortion Induced by Blue Light Delivery in the Nave Brain: Implications for Optogenetic fMRI Studies

Russell W. Chan 1,2 , Alex T.L. Leong 1,2 , Joe S. Cheng 1,2 , Victor B. Xie 1,2 , Partick P. Gao 1,2 , Aaron Mok 2 , Kevin K. Tsia 2 , and Ed X. Wu 1,2

1 Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong, China, 2 Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong, China

Previously, it has been reported that blue light delivery in the nave brain resulted in pseudo positive and negative fMRI responses, which were attributed to NMR frequency shifts, and T1 and T2* changes. EPI is known to be susceptible to NMR frequency shifting, field inhomogeneity and T2* changes. However, the effects of blue light delivery in the nave brain and EPI distortion have not been examined. The aim of this study was to investigate the local EPI distortion induced by laser stimulation in the nave posterior thalamus. Our results showed that the pseudo negative fMRI response was at the fiber tip, while the pseudo positive fMRI response was adjacent to the pseudo negative fMRI response along the phase encoding direction. This study brings attention to EPI distortion as a possible confounder which must be taken into account when optogenetic fMRI experiments are designed.

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.

Keywords