Abstract #4375

CRLB minimization for optimal Multi Spin-Echo T2-mapping of the cartilage using dictionary-based estimation

Tiago Timoteo Fernandes^1,2, Sairam Geethanath², and Rita G Nunes³

¹nstitute for Systems and Robotics - Lisboa and Department of Bioengineering, Instituto Superior Técn, Lisboa, Portugal, ²Accessible Magnetic Resonance Laboratory, Biomedical Imaging and Engineering Institute, Department of Diagnostic, Molecular and Interventional Radiology, Icahn School of Medicine at Mount Sinai, New York, NY, United States, New York, NY, United States, ³Institute for Systems and Robotics - Lisboa and Department of Bioengineering, Instituto Superior Técnico – Universidade de Lisboa, Lisbon, Portugal, Lisboa, Portugal

Synopsis

Keywords: Cartilage, Quantitative Imaging.We compared Cramer-Rao Lower Bounds of Multi Spin-Echo sequences’ derived T2 values using a dictionary approach for musculoskeletal relaxometry. The refocusing flip angle, inter-echo spacing and echoe number were varied, constraining the B1+rms to 5μT and the exam time to 9 minutes, keeping TR to a minimum. Designed sequences were tested in NIST/ISMRM phantom and ex vivo, and compared against the vendor’s MSE. A repeatability study was performed during 5 days. An optimized sequence with target T2 value (45ms), representative of the cartilage, scored below 10% for Within-case Coefficient of Variation in 9 out of 14 vials.

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.