There are still several challenges in acquiring high-quality MR images when using high magnetic field systems, such as the 7 Tesla. Three key issues prevent these systems from functioning at their highest potential: (1) nonuniformities in signal and contrast due to increased inhomogeneities in the applied radiofrequency (RF) field (B1 field), (2) limited strength and number of RF pulses due to an increase in RF deposition, and (3) reduced sequence timing and contrast due to changes in T1 and T2 tissue relaxation parameters.
Dr. Priti Balchandadani, Director of the High Field MRI Program at the Translational and Molecular Imaging Institute at the Icahn School of Medicine, and neuroimaging postdoctoral fellow, Dr. Rebecca Feldman, have developed a technique using an RF pulse pair combined with a gradient pulse sequence to improve MR image acquisition and quality. The Semi-Adiabatic Matched-Phase Multi-Slice Spin-Echo (SEAMS) power independent of number of slices (PINS) sequence can be used to accelerate slice acquisition in magnetic resonance imaging while overcoming technical challenges that reduce signal magnitude at high magnetic fields. SEAMS PINS simultaneously acquires multiple slices using RF excitation and adiabatic refocusing pulses that are less sensitive to inhomogeneities in the RF field. The excitation and refocusing pulses have been designed to complement each other and eliminate the quadratic phase that the adiabatic refocusing pulse deposits across the selected slice. This pulse design results in higher signal magnitude, which can be parlayed into increased image resolution, as well as more rapid acquisition of total image volumes.
Current Development Status
- Human subject pilot data
Applications
- Enhanced image quality and acquisition in high field strength systems
- Library of pulse sequences available for clinical and research MRI exams
Advantages
- Improved image quality and decreased duration of the scan through:
- Reduction in tissue relaxation times
- Reduced subject power deposition
- Less sensitivity to B1 inhomogenity
- Elimination of signal loss due to long echo times
Publications
- Feldman, Rebecca E.et al. “A semi-adiabatic matched-phase spin echo (SEAMS) PINS pulse-pair for B1-insensitive simultaneous multisclice imaging.” Magnetic Resonance in Medicine. 2015
Patent Status
- US Provisional Application 62/112,802 filed February 6, 2015
- US Utility Application 14/697,040 filed April 27, 2015
Contact
Idoia Gamez, PhD, MBA
Business Development Director
Mount Sinai Innovation Partners | Icahn School of Medicine at Mount Sinai
Phone: 646.605.7317