TRADITIONAL POSTER - ismrm

Poster Sessions
2971. Tandem Dual-Echo Fast Spin Echo with Inversion Recovery (Tandem-IR-DE-FSE): A Multi-Platform
Pulse Sequence for Multispectral Quantitative-MRI (PD, T1, T2)
Hernan Jara 1 , Stephan W. Anderson 1 , Osamu Sakai 1 , Jorge A. Soto 1
1 Boston University School of Medicine, Boston, MA, United States
Purpose: There is great need for multi-spectral quantitative-MRI (qMRI) pulse sequences that can be readily implemented in MRI scanners of different
manufacturers and field strengths. Methods: The Tandem-IR-DE-FSE sequences were implemented in GE (1.5T-SIGNA HDx) and Bruker 11.7T scanners.
Results: Excellent directly-acquired and qMRI map image quality was obtained with both scanners: PD, T1, and T2 maps of the brain are of good image
quality and also are give qMRI measures in good agreement with accepted values. Conclusion: The Tandem IR-DE-FSE sequence can produce multispectral
qMRI maps of PD, T1, and T2 that are self co-registered, high spatial resolution, and with clinical coverage.
2972. High Resolution Multispectral QMRI Protocol: PD, T1, T2, T2*, ADC, MT
Stephan William Anderson 1 , Jorge A. Soto 1 , Hernan Jara 1
1 Radiology, Boston University Medical Center, Boston, MA, United States
The purpose of this study was to develop a high-resolution, multi-spectral, quantitative magnetic resonance imaging (qMRI) pulse sequence protocol to
interrogate T1, T2, T2*, proton density (PD), diffusion coefficient, and magnetization transfer parameters at ultra-high field (11.7T) MRI. This multispectral
qMRI pulse sequence was applied to a qMRI phantom containing water, agarose gels, sucrose solutions, and olive oil. Also, the protocol was
applied to ex vivo liver imaging of a murine model of steatohepatitis as well as ex vivo murine brain imaging. This comprehensive, multi-spectral qMRI
protocol was successfully implemented at 11.7T MRI
2973. Comparison of Magnetic Field Correlation in Brain at 1.5 and 3 Tesla
Caixia Hu 1,2 , Jens H. Jensen 1 , Casian Monaco, Kathleen Williams, Joseph A. Helpern 1,2
1 Radiology, New York University School of Medicine, New York, NY, United States; 2 Center for Advanced Brain Imaging, Nathan
S. Kline Institute, Orangeburg, NY, United States
The magnetic field correlation is theoretically predicted to scale as the square of the applied field. This was verified experimentally in brain for two subjects
by scanning them at 1.5T and 3T. The magnetic field correlation was estimated by using a recently proposed MRI method based on asymmetric spin echoes.
The consistency of the experimental results with the theoretical prediction constitutes an important validation for the imaging method and helps to justify its
application at clinical field levels. Magnetic field correlation can be of interest for studying brain iron changes associated with neuropathologies, such as
Alzheimer’s disease and multiple sclerosis.
Ultra Short TE
Hall B Tuesday 13:30-15:30
2974. Ultra-Short Echo-Time (UTE) Imaging for Early Diagnosis of Dental Demineralization
Anna-Katinka Bracher 1 , Christian Hofmann 2,3 , Said Boujraf 4 , Axel Bornstedt 1 , Erich Hell 5 , Johannes
Ulrici 5 , Axel Spahr 2 , Volker Rasche 1
1 Department of Internal Medicine II, University Hospital of Ulm, Ulm, Baden-Württemberg, Germany; 2 Department of Operative
Dentistry, Periodontology and Pedodontics, University Hospital of Ulm, Ulm, Germany; 3 Department of Internal Medicine II,
University Hospital of Ulm, Ulm, Baden-Württemberg, Germany; 4 Department of Biophysics and Clinical MRI Methods, Faculty of
Medicine and Pharmacy, University of Fez, Morocco; 5 Sirona Dental Systems GmbH, Bensheim, Germany
Due to the high mineral content, the concentration of free protons is extremely low causing only weak magnetization and due to the susceptibility interfaces
in the mineral structures, the spin-spin relaxation rates results below 1ms for dentin and below 250µs for enamel. During caries lesion formation, some
increase in liquid content resulting from the production of acid or caused by water penetrating into the lesion through the porous demineralized enamel layer
is expected. The performance of ultra-short echo time (UTE) MRI for early assessment of lesion formation was investigated and compared to X-ray imaging.
2975. Theoretical Sensitivities of SWIFT and the Ideal Sequence (Delta Pulse-Acquire) for Ultra-Short T2
Robert Daniel O'Connell 1 , Steen Moeller 1 , Djaudat Idiyatullin 1 , Curt Corum 1 , Michael Garwood 1
1 Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States
A comparison is made between infinitely short RF pulses (delta), hard pulses and SWIFT using the Ernst energy equation and Bloch simulations. Simulation
results are reported for each pulse sequence for on- and off-resonance systems at T1=T2. The SWIFT, delta pulse, and long T1,2 on-resonance hard-pulse
sequences are described by the Ernst equations. On-resonance hard pulses have signal energy loss for short T1,2. Off-resonance hard pulses are not
described by the Ernst equations. In addition to being unaffected by resonance offsets, for any flip angle the SWIFT sequence results in having a signal
energy peak at shorter T1,2 than the other sequences.
2976. 3D Ultrashort Echo Time (UTE) Imaging in the Brain at 7T
Peder E. Z. Larson 1 , Duan Xu 1 , Daniel B. Vigneron 1
1 Radiology and Biomedical Imaging, University of California - San Francisco, San Francisco, CA, United States
Ultrashort echo time (UTE) imaging of the brain has the potential for direct detection of myelin, calcifications and other short-T2 components that are
altered in neurodegenerative diseases and other neurological pathologies. Ultra high-field MRI at 7T offers improved SNR for detection of these
components which generally have low signal intensity. In this project, we have developed a 3D radial UTE acquisition for 7T brain imaging providing full
head coverage in just over 5 mins. Both dual-echo subtraction and off-resonant saturation pulses were applied yielding good contrast of connective tissues
and white matter short-T2 components.