MRI Acquisition

The MRI protocols followed guidelines established by the American College of Radiology breast MRI accreditation program⁵⁶. The protocol included a 3D T1-weighted fast gradient echo-based DCE series with one pre and three sequential post-gadolinium contrast-enhanced sequences with scan durations of approximately 3 min each. All scans were performed on a 3 Tesla Philips Achieva Tx system (Philips Medical Systems, Best, the Netherlands) with a 16-channel breast coil (Mammotrak, Philips Healthcare). DCE-MRI was performed using a fat saturated 3D fast gradient echo sequence (eTHRIVE: enhanced T1-weighted High Resolution Isotropic Volume Excitation) with the following parameters: TR/TE = 5.9/3 msec, flip angle = 10°, spatial resolution = 0.5 × 0.5 × 1.3 mm. Post-contrast sequences were acquired with k space centered at approximately 120, 300, and 480 s after contrast injection. All scans were acquired in the axial orientation. The contrast agent administered was 0.1 mmol/kg body weight gadoteridol (ProHance, Bracco Diagnostics, Milan, Italy) at the rate of 2 cc/s followed by a 15 cc saline flush.