ELECTRONIC POSTER - ismrm

15:00 3759. Non Contrast MRA of the Renal Artery: Comparison of Respiratory Triggered
IFIR and ECG Gated IFIR with Autovoice Guidance for Respiration
Takayuki Masui 1 , Motoyuki Katayama 1 , Kimihiko Sato 1 , Hiroki Ikuma 1 , M Sugimura 1 , M
Ishii 1 , Naoyuki Takei 2 , Mitsuharu Miyoshi 2
1 Radiology, Seirei Hamamatsu General Hospital, Hamamatsu, Japan; 2 Japan Applied Science Laboratory, GE
Healthcare Japan, Hino, Japan
Non-contrast (NC) MRAs including inflow inversion recovery (IFIR) FIESTA have shown promising results for demonstration of the
renal arteries but might show irregularity in the most peripheral parts of the renal arteries. The purpose was to evaluate effect of
autovoice guiding respiratory cycle with ECG gating (IFIR with autovoice) on the quality of NC MRA for demonstration of renal
arteries in comparison with contrast MRA. MRA using IFIR with autovoice could provide best image quality of the peripheral renal
arteries when autovoice successfully guided respiration. Contrast MRA might miss the optimal timing for selective visualization of the
renal arteries.
15:30 3760. Two-Station Time-Resolved 3D Contrast-Enhanced MRA with Real-Time Station
Switching
Casey Peter Johnson 1 , Clifton R. Haider 1 , Eric A. Borisch 1 , Roger C. Grimm 1 , Phillip J.
Rossman 1 , Thomas C. Hulshizer 1 , Jake C. Snell 1 , James F. Glockner 1 , Stephen J.
Riederer 1
1 Department of Radiology, Mayo Clinic, Rochester, MN, United States
The purpose of this work was to improve bolus-chase MRA techniques by imaging multiple stations with both high spatial and
temporal resolution. A highly-accelerated (14x) CAPR acquisition, previously demonstrated for single-station MRA of the calves,
was adapted for this purpose. As part of the implementation, a system was developed to reconstruct the CAPR images in real time and
allow for visually-guided station switching. Vasculature of the thighs and calves of volunteers was imaged with 1.0 mm isotropic
resolution and frame times as low as 2.5 seconds. High-quality arterial frames were consistently acquired in both stations while
avoiding venous contamination.
Tuesday 13:30-15:30 Computer 41
13:30 3761. Unenhanced ECG-Gated Fast Spin-Echo MR Digital Subtraction Angiography
(MRDSA) Using SPACE with Constant Flip Angle Mode of Femoral Arteries
Satoru Morita 1 , Shinya Kojima 1 , Masami Hirata 1 , Masaru Suzuki 1 , Kazufumi Suzuki 1 , Ai
Masukawa 1 , Eiko Ueno 1
1 Department of Radiology, Tokyo Women's Medical University Medical Center East, Arakawa-ku, Tokyo,
Japan
Unenhanced electrocardiographically-gated fast spin-echo-based magnetic resonance digital subtraction angiography (MRDSA) can
obtain hemodynamic information of pulse wave transmission. We prospectively compared the image quality of MRDSA using
sampling perfection with application optimized contrasts using different flip angle evolutions (SPACE) with constant flip angle mode
and conventional half-Fourier single-shot turbo spin-echo (HASTE) sequence of femoral arteries in 10 healthy volunteers at 1.5T
MRI. All quantitative and qualitative analyses of the SPACE were significantly better than those of the HASTE. We show that
unenhanced electrocardiographically-gated fast spin-echo MRDSA using SPACE with constant flip angle mode provides good visual
hemodynamic information of arteries.
14:00 3762. Nonenhanced Time-Resolved MR Angiography for the Arteriovenous
Malformation/Fistula of the Pelvis and the Lower Extremity.
Masaaki Akahane 1 , Jiro Sato 1 , Shuhei Komatsu 1 , Yasushi Watanabe 2 , Yoshiro Satake 2 ,
Kuni Ohtomo 1
1 Radiology, University of Tokyo, Bunkyo-ku, Tokyo, Japan; 2 Clinical Radiology, University of Tokyo,
Bunkyo-ku, Tokyo, Japan
Nonenhanced MRA by spin-labeling technique with subtraction between labeled and non-labeled images was applied to the timeresolved
study for better background suppression in any inversion time. Seven patients having arteriovenous malformations or fistulas
of the pelvis or lower extremity underwent nonenhanced time-resolved MRA using respiratory-gated balanced steady state free
precession (SSFP) sequence with 1.5-T scanner (Toshiba EXCELART Vantage, Japan). Inversion times (TI) were assigned as 300,
800, 1300 and 1800 ms. Nonenhanced time-resolved MRA was useful for the evaluation of hemodynamics of the arteriovenous
malformation or fistula and the distinction of feeding arteries.
14:30 3763. Adapted Random 3D Sampling Patterns for CE-MRA
Florian Knoll 1 , Christian Clason 2 , Manuela Aschauer 3 , Franz Ebner 3 , Rudolf
Stollberger 1
1 Institute of Medical Engineering, Graz University of Technology, Graz, Austria; 2 Institute for Mathematics and
Scientific Computing, University of Graz, Graz, Austria; 3 Department of Radiology, Medical University Graz,
Graz, Austria
Variable density 3D random sampling trajectories have great potential for subsampled CE-MR angiography techniques which deliver
data sets with high contrast to noise ratio. The goal of this work was to present a parameter-free method to construct variable density