Low-dose intra-arterial contrast-enhanced MR aortography in patients based on a theoretically derived injection protocol
Potthast, S. ; Schulte, A.-C ; Bongartz, G. ; Hügli, R. ; Aschwanden, M. ; Bilecen, D.
In: European Radiology, 2005, vol. 15, no. 11, p. 2347-2353
Ajouter à la liste personnelle- Summary
- Multiple intra-arterial contrast agent injections are necessary during MR-guided endovascular interventions. In respect to the approved limits of maximum daily gadolinium dose, a low-dose injection protocol is mandatory. The objective of this study was to derive and apply a low-dose injection protocol for intra-arterial 3D contrast-enhanced MR aortography in patients. Injection rate (Qinj), concentration of injected gadolinium [Gd]inj and aortal blood flow rate (Qblood) were included for the theoretical evaluation of signal intensity (SI) of the arterial lumen. SI simulations were carried out at Qinj=2 versus 4ml/s in the [Gd]inj range between 0-500mM. Qinj and [Gd]inj with SI above the 75% threshold of the maximal SI were regarded as optimal injection parameters. [Gd]inj=50mM and Qinj=4ml/s were considered as optimal and were administered in five patients for 3D MR aortography. All images revealed clear delineation of the abdominal aorta and its major branches. Mean±SD of contrast-to-noise ratios of the abdominal aorta, common iliac and renal artery were 70.2±15.2, 58.6±12.3 and 67.4±12.3. Approximately seven intra-aortal injections would be permissible in patients during MR-guided interventions without exceeding the maximal dose of gadolinium