Meeting Banner
Abstract #3438

Multiphoton Excitation Enabled Simultaneous Multislice Parallel Transmission at 7T

Tanya Deniz Ipek1, Victor Han1, Philippa Krahn1, and Chunlei Liu1,2
1Electrical Engineering and Computer Sciences, University of California, Berkeley, Berkeley, CA, United States, 2Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, United States

Synopsis

Keywords: Parallel Transmit & Multiband, Parallel Transmit & Multiband, Multiphoton, SMS, pTx, B1 inhomogeneity, SAR

Motivation: Simultaneous multislice (SMS) acquisitions are beneficial for high-resolution scans at ultrahigh field (UHF), however, they are limited by transmit $$$B_1\:(B_1^+)$$$ inhomogeneity and high specific absorption rate (SAR).

Goal(s): To utilize multiphoton excitation for reducing $$$B_1^+$$$ inhomogeneity and SAR for SMS at UHF.

Approach: We optimize the RF shim coefficients of Multiphoton SMS pulses using magnitude least squares optimization and transmit sensitivity maps at 7T. We evaluate the performance of Multiphoton SMS pTx with Bloch simulations.

Results: Multiphoton SMS achieves comparable $$$B_1^+$$$ homogeneity to Full pTx MB while reducing the total RF power by up to 28% for three slices and 47% for five.

Impact: This work demonstrates the effectiveness of combining Multiphoton SMS with pTx, achieving comparable homogeneity to Full pTx MB while reducing RF power requirements. Multiphoton SMS pTx provides a promising approach for more efficient and safer SMS excitation at ultrahigh fields.

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