Purpose: To study the possibility of using independent component analysis (ICA) to identify breast lesions as separate hemodynamic sources on dynamic contrast-enhanced (DCE) MR images, as depicted by the passage of contrast medium.
Materials and methods: Six patients who were histopathologically confirmed with breast carcinoma underwent DCE MRI with 5 precontrast and 60 postcontrast scans at a time-resolution of 8 s. A spatial ICA algorithm was applied on the DCE MRI data set to extract spatial component maps corresponding to source locations with different signal time-intensity patterns. To verify the present hypothesis of the ability of ICA to reveal tumor voxels as a separate hemodynamic phase, tumor margins were outlined by an experienced radiologist who was blinded from the ICA results, and the manual outlines were compared with the ICA maps.
Results: Consistently for each of the six patient study cases, it was found that ICA yields a tumor component map associated with typical tumor enhancement patterns of rapid enhancement with washout or plateau. Tumor outlines manually drawn by the radiologist were in good agreement with the tumor locations depicted in the tumor component maps.
Conclusion: ICA may provide an objective method for identifying the outlines of enhancing breast tumors on DCE MR images and to automatically extract the tumor signal intensity-time curve for subsequent tracer kinetics analysis.
(c) 2008 Wiley-Liss, Inc.