Hybrid Ultrasound MRI for Improved Cardiac Imaging
and Real-Time Respiration Control
David A. Feinberg,1–3* Daniel Giese,6 D. Andre Bongers,4 Sudhir Ramanna,1
Maxim Zaitsev,6 Michael Markl,6 and Matthias Gu¨ nther1,4,5
Magnetic Resonance in Medicine 63:290–296 (2010)
A hybridized dual-imaging system combining real-time ultra-
sound imaging and MRI was utilized for cardiac imaging at
1.5 T and 3 T. The ultrasound scanner with a programmable
software interface was connected via computer to the MRI
scanner. Electronic noise was eliminated with electromagnetic
shielding and grounding to the screen room. At 3 T, real-time
prospective motion compensation in dynamic cine cardiac
imaging was implemented using B-mode ultrasound imaging.
The ultrasound technique avoided drawbacks such as signal
saturation or steady-state interruption of the MR navigator
gating. At 1.5 T, a low-latency real-time feedback to balanced
steady state free precision MR imaging was performed in
three normal volunteers. Results showed active tracking of
the heart during respiratory motion and improvement in time-
averaged cardiovascular images. Future studies can fully
exploit the potential of the high-frequency position informa-
tion provided by the ultrasound system for more advanced
applications in real-time organ tracking.
Key words: ultrasound; MRI; cardiac MRI; navigator echo
No comments:
Post a Comment