Quantitative assessment of breast tumor: comparison of different region of interest for synthetic relaxometry and diffusion measurement

Motivation: The lack of guidelines or recommendations for the ROI size of DWI and synthetic MRI. Goal(s): To investigate the effect of different ROI positioning methods on both ADC and synthetic MRI measurements and to subsequently evaluate the diagnostic performance of differently shaped ROIs. Approach: Four different ROI positioning methods on ADC and synthetic parameters measurements. Results: Square ROI showed the optimal AUC followed by freehand ROI. T2 + ADC were more diagnostic than ADC or T2 alone. Impact: The different ROI positioning methods used had a significant impact on the quantitative measurements and the performance in differentiating benign from malignant breast tumors.