Authors:
R. Ochiai, H. Sugimura, T. Kodama, T. Jinnouchi, E. Furukouji, T. Sakae, S. Tamura; Kiyotake/JP
DOI:
10.1594/ecr2009/C-833
Purpose
Gadolinium-enhanced magnetic resonance angiography (MRA) is increasingly being used as the technique of choice for imaging the vascular system. This technique has several advantages over conventional digital subtraction angiography (DSA). MRA is non-invasive and does not require ionizing radiation. Moreover, the gadolinium contrast agent used has minimal renal effects; this renders the technique particularly useful in patients with concurrent renal failure. However, it has been recently reported that a serious adverse effect called nephrogenic systemic fibrosis (NSF) may occur after exposure to gadodiamide, an extracellular, nonionic, low-osmolar, gadolinium-based contrast agent. Therefore, currently, a gadolinium-based contrast agent cannot be used in patients severe renal dysfunction.
Non-contrast-enhanced MRA, which can depict blood vessels, can be performed using time-of-flight (TOF) methods, phase-contrast methods, ECG-gated 3D partial-Fourier fast spin echo methods, or arterial spin labeling (ASL) methods. ASL involves the use of water in arterial blood as an endogenous contrast material to non-invasively evaluate perfusion. ASL can also be combined with a fast imaging method such as true steady-state free precession (SSFP). This combination method is available for MR portogaphy, but poor depiction of the portal vein and its branches have been reported occasionally.
In cases of renal dysfunction, a superparamagnetic iron oxide particle (SPIO), which has a high R2/R1 relaxivity ratio, may be used as a blood pool contrast agent.
In this study, we aimed to evaluate the effects of SPIO administration on the quality of spin labeling portography.