Abstract #2652

Evaluation of Accelerated SEMAC at 0.55T using Hexagonal Sampling and Parallel Imaging

Bahadır Alp Barlas¹, Kübra Keskin¹, Bochao Li², Brian A Hargreaves^3,4,5, and Krishna S Nayak^1,2

¹Electrical and Computer Engineering, University of Sourthern California, Los Angeles, CA, United States, ²Biomedical Engineering, University of Southern California, Los Angeles, CA, United States, ³Radiology, Stanford University, Stanford, CA, United States, ⁴Electrical Engineering, Stanford University, Stanford, CA, United States, ⁵Bioengineering, Stanford University, Stanford, CA, United States

Synopsis

Keywords: Artifacts, Low-Field MRI

Motivation: Low-field and mid-field MRI systems have tremendous potential for imaging near metal implants with reduced artifacts, but reduced ability to do parallel imaging limits encoding options.

Goal(s): To achieve 50% scan time reduction in addition to conventional parallel imaging at 0.55T.

Approach: Hexagonal sampling (in k_y-k_f space) combined with GRAPPA-2 in SEMAC acquisitions was evaluated qualitatively and quantitatively via phantom and in vivo experiments at 0.55T.

Results: GRAPPA-2 hexagonal sampling achieved comparable image quality to conventional GRAPPA-2 SEMAC with slight SNR reduction and a modest increase in artifact area, while allowing a 50% decrease in scan time.

Impact: We evaluate the performance of hexagonal sampling combined with GRAPPA-2 at 0.55T where high parallel imaging factors are challenging via phantom and in vivo experiments. 50% additional scan time reduction is achieved with a modest increase in artifact area.

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.