Our subjects included 105 women (aged 22–75 years,
mean age 47 years) with a pathological diagnosis of Invasive breast cancer of no specific type (35 solid,
35 tubule forming,
and 35 scirrhous type) between January 2016 and March 2016.
The imaging conditions of MRI were as follows:
・Device: MRI (1.5 T) MAGNETOM Symphony SIMENS -4 channels breast array coil,
contrast injector for MRI Sonic shot GX.
・Contrast-enhanced MR
The different phases included,
pre (pre_phase),
after 1 min (injection_phase),
after 2 min (peak _phase),
and after 6 min (delay_phase).
・Gadolinium contrast agent: Magnevist® intravenous injection Syringe,
Injection rate 2.0 ml/sec
・ Imaging protocol
TR: 5.42,
TE: 2.11,
Flip angle: 20°,
Fat saturation (+),
slice thickness: 1 mm,
Slabs: 1,
slices slab: 96,
scan time: 60 sec (×4),
band width: 300 Hz/pixel,
GRAPPA (Accelerating factor PE:2,Ref.
lines PE:50),
Averages: 1,
section: coronal,
FOV: 330 mm,
FOV phase: 50%,
Base resolution: 512,
Phase resolution: 80%,
Slice resolution: 90%,
Phase encoding direction: F>>H,
Phase oversampling: 63%,
Slice oversampling: 0%,
Matrix size: 512 × 256,
Pixel size: 0.8 × 0.6 mm.
Personal information has been protected while providing the clinical images in this study,
so that subjects cannot be identified (all personal information is anonymous,
except for MRI,
pathological diagnosis name,
and tumor location information).
Furthermore,
we have obtained the approval of the Institutional Ethical Review Board for the use of the clinical image.
As shown in Fig.
2,
in TIC analysis,
we defined the inclination of signal intensity between pre_phase and injection_ phase as theta1 (θ1) and that between the injection_phase and peak _phase as theta2 (θ2).
And,
we consider the relationship between the three types (Solid type,
Tubule forming type,
Scirrhous type) and Angles (Angle A:θ2 < θ1,Angle B: (0.5 × θ2) < θ1<=θ2,Angle C:θ1 <= (0.5×θ2)) using θ1 and θ2
TIC is created for every pixel in the washout effect region in the lesion,
which suggests a malignancy.
Thereafter,
the Angle is determined from θ1 and θ2 in the TIC.
Similarly,
in all the TICs,
an Angle is determined,
respectively.
And,
we decided the most Angle in the case to be the Angle of the case.
An extract of the washout effect region,
creation of TIC,
and the most Angle (A,
B,
C) from this study was processed by the computer,
which was then used in the original work program (Fig.
3,
4)[20].