title: Hybrid ultrasound MRI for improved cardiac imaging and real-time respiration control.
abstract: A hybridized dual-imaging system combining real-time ultrasound 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 information provided by the ultrasound system for more advanced applications in real-time organ tracking.
authors.affiliation: Advanced MRI Technologies, Sebastopol, California 95472, USA. david.feinberg@advancedmri.com
authors.forename: David A
authors.initials: DA
authors.lastname: Feinberg
authors.forename: Daniel
authors.initials: D
authors.lastname: Giese
authors.forename: D Andre
authors.initials: DA
authors.lastname: Bongers
authors.forename: Sudhir
authors.initials: S
authors.lastname: Ramanna
authors.forename: Maxim
authors.initials: M
authors.lastname: Zaitsev
authors.forename: Michael
authors.initials: M
authors.lastname: Markl
authors.forename: Matthias
authors.initials: M
authors.lastname: Günther
mesh_terms: D003199:Computer Systems; D004452:Echocardiography / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006321:Heart / Q000033:anatomy & histology*; D006801:Humans; D007089:Image Enhancement / Q000295:instrumentation*; D008279:Magnetic Resonance Imaging / Q000295:instrumentation*; D019047:Phantoms, Imaging; D015656:Respiratory Mechanics; D055425:Respiratory-Gated Imaging Techniques / Q000295:instrumentation*; D012680:Sensitivity and Specificity; D018511:Systems Integration; D014463:Ultrasonography / Q000295:instrumentation*