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Rapid Scan Electron Paramagnetic Resonance Opens New Avenues for Imaging Physiologically Important Parameters In Vivo
Published on: September 26, 2016
Real-time NMR beam-directed velocity mapping. V-mode NMR
J D Pearlman1, J R Moore, M J Lizak
1Department of Medicine, Massachusetts General Hospital, Boston.
Circulation
|November 1, 1992
Summary
V-mode nuclear magnetic resonance (NMR) allows real-time blood flow velocity measurement at any angle, overcoming limitations of current techniques. This novel MRI method provides clinically relevant data for cardiac and vascular studies.
Area of Science:
- Medical Imaging
- Cardiovascular Physiology
- Biomedical Engineering
Background:
- Current noninvasive blood flow velocity measurements have limitations in view orientation (Doppler ultrasound) or temporal resolution (MRI).
- There is a need for advanced techniques to capture real-time hemodynamic data.
- V-mode nuclear magnetic resonance (NMR) offers a potential solution.
Purpose of the Study:
- To introduce and evaluate V-mode NMR for real-time blood flow velocity measurement.
- To assess the technique's performance in arbitrary orientations.
- To demonstrate its clinical applicability.
Main Methods:
- Implementation of V-mode NMR on a standard 1.5-T clinical NMR imager.
- Testing the technique on phantoms and human volunteers.
- Acquisition of flow velocity data at rates up to 60 Hz.
Main Results:
- High correlation (r > 0.99) between measured and actual velocities in phantoms.
- Successful measurement of blood flow in human descending aortas.
- Detection of distinctive backflow in subjects with aortic insufficiency.
Conclusions:
- V-mode NMR enables real-time acquisition of clinically relevant blood flow information.
- The technique allows measurements from any desired angle of view.
- It is not affected by attenuation at bone or air-tissue interfaces, offering broad applicability.
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