[Dynamic 3D MR mammography using a rapid gradient-echo sequence].

Up to now, MR mammography is performed by two different methods: 2-D techniques with high temporal resolution and 3-D techniques with high spatial resolution. This article investigates whether a dynamic examination of the breast using a novel 3-D-gradient-echo sequence is feasible with sufficient spatial and temporal resolution. MR imaging was performed on a 1.0 Tesla imager using a gradient field strength of 15 mT/m. Phantom measurements were done to evaluate the correlation between signal intensity and contrast medium concentration for different sequences. Subsequently, 40 patients with 22 histologically verified lesions were examined using the double breast coil and a novel FLASH3D sequence (TR/TE/fa 9/3/50 degrees). Reading of the films in standardized documentation, multiplanar reconstruction (MPR), calculation and maximum intensity projection (MIP) of subtraction images as well as signal-to-time curve calculations in selected ROIs were performed for data evaluation. In the phantom measurements the FLASH3D-9/3/50 degrees sequence yielded the best correlation between signal intensity and Gd-DTPA concentration. The sequence provided good visualization even of small lesions. The 3-D postprocessing procedures facilitated the detection and localization of the lesions. Therefore, the new FLASH3D-9/3/50 degrees sequence enables a dynamic 3-D examination of the breast with a sufficient spatial and temporal resolution.