Combined high-resolution and real-time imaging: A technical feasibility study on coronary magnetic resonance angiography

Purpose: To propose a new approach to combining high-resolution and real-time imaging and to show its technical feasibility on the example of coronary magnetic resonance angiography. Materials and Methods: The insertion of fast two-dimensional (2D) acquisitions into time intervals that have not been utilized by triggered or gated 2D or three-dimensional (3D) acquisitions so far is suggested, as well as the immediate reconstruction and display of the additional data. For a technical validation of this concept, a 2D ventricular function protocol was interleaved into a cardiac-triggered and respiratory-gated 3D coronary angiography protocol. Dedicated hardware was employed to rapidly process the data originating from the former. Since the sampling of the latter was restricted to intervals with minimal motion, remaining periods of time could be used to simultaneously image the cardiac and respiratory motion. Results: The technical feasibility of the proposed approach was demonstrated by successful measurements with the combined high-resolution and real-time protocol in volunteers. All examinations provided short axis views during the acquisition and angiograms of selected parts of the coronary system after its completion. Conclusion: The investigated concept allows high-resolution measurements to be complemented with real-time imaging functionality without affecting the scan time or image quality. In the particular application considered, an image-based patient monitoring or motion correction is enabled, indicating potential benefits of combining two very dissimilar methods of data acquisition in one measurement.