Dynamic contrast-enhanced MRI using Gd-DTPA: Interindividual variability of the arterial input function and consequences for the assessment of kinetics in tumors

✍ Scribed by Ruediger E. Port; Michael V. Knopp; Gunnar Brix

• Publisher: John Wiley and Sons
• Year: 2001
• Tongue: English
• Weight: 244 KB
• Volume: 45
• Category: Article
• ISSN: 0740-3194
• DOI: 10.1002/mrm.1137

✦ Synopsis

Gd-DTPA kinetics in arterial blood was investigated by dynamic MRI in 47 patients with malignant and benign mammary tumors. Signal enhancement was monitored for 10 min after the beginning of a 1-min infusion of 0.1 mmol/kg Gd-DTPA. Kinetics in blood was biexponential with median half-lives of 21 sec and 11.1 min, respectively. Peak signal enhancement and the area under the signal enhancement-time curve varied 2.5- and 3.7-fold between patients. The shortest mean residence time in one of up to three tumor compartments, MRT*, was estimated using either the individual (reference) or a mean population (surrogate) arterial input function (AIF). MRT* (reference estimate) was 1.0 (0-1.5), 1.9 (1.5-2.3), and 2.5 (2.3-2.8) min in carcinomas, fibroadenomas, and mastopathies, respectively (median and interquartile distance). Surrogate estimates were unbiased but differed from the reference estimates 1.5-fold or more in 23% of cases. AIFs should be monitored individually if accurate estimates of individual MRT* are desired.