CARDIAC MR FLOWMETRY - EXPERIMENTAL VALID ATION AND RESULTS IN PATIENTS WITH OPERATED CARDIAC DEFICIENCIES

Purpose: A flow-sensitive MR sequence (phase-contrast technique) was e valuated in phantom studies with regard to factors influencing measure ments and correctness of results. The sequence was additionally used f or functional evaluation of operated congenital heart disease. Methods : Pulsatile and constant flow were produced with the help of a phantom . Influence of angulation, range and vessel bending was evaluated. An examination protocol was developed from the results. 35 patients with surgically repaired congenital heart disease or without repair were ex amined. Results: A range preset below the actual flow velocity as well as angulation of more than 20 degrees were isolated as main pitfalls in MR flowmetry. In addition to morphological MR findings flow measure ments were possible in 11 patients at vessel sites which were not or n ot completely suited for examination by Doppler ultrasound. Conclusion : The evaluated phase-contrast technique allows for fast and reliable flow quantification if the influences identified in phantom studies ar e considered.