Magnevist

CMR images were obtained using Siemens 3.0 T CMR scanners (Skyra; Siemens Medical Solutions, Erlangen, Germany) in a supine position with the head first. Electrocardiographic gating and respiratory gating were adopted during the scanning. Cine-CMR views, including 2- and 4-chamber long-axis views and a set of short-axis views covering the entire LV, were required using the sequence of balanced steady-state free-precession. Scan parameters included the field of view = 350–400 mm, repetition time/echo time = 3.0–3.6/1.5–1.8 ms, flip angle = 60°, and slice thickness = 8 mm. Late gadolinium enhancement (LGE) images were obtained 10 to 15 min after intravenous administration of gadodiamide (Magnevist; Bayer Schering Pharma, Berlin, Germany) at a speed of 0.2 mmol/kg scanned by the inversion recovery echo sequence. Its parameters included field of view = 350–400 mm, repetition time/echo time = 4.5–4.6/1.3–1.5 ms, flip angle =15°, inversion time = 200–300 ms, and slice thickness = 8 mm.

To evaluate the BBB permeability, 0.5 mmol/kg of Gd-DTPA (Magnevist, Bayer Schering Pharma, Berlin, Germany) was injected into mice 10 min before MR imaging. T1-weighted images (T1WI) were acquired by spin echo multi-slice sequence before and after injection of Gd-DTPA. The imaging parameters were TR = 500 ms, TE = 10.35 ms, FOV = 25.6 × 25.6 mm, matrix = 96 × 96, slice thickness = 1.0 mm, average = 4, and dummy = 2. After T1WI, T2-weighted images were acquired by spin echo sequence. The imaging parameters were TR = 2500 ms, TE = 50 ms, and average = 1. Image analysis was performed using ImageJ (NIH, Bethesda, MD). Briefly, the percent increase in MRI signal intensity images compared to the respective pixel in the pre-injection images was calculated. To quantify the BBB leakage areas, we set ROIs in two slices shown in Fig. 4a. The threshold was set at the mean percent increase plus two standard deviations in the normal hemisphere. A higher percent increase value than the threshold was considered as BBB disruption areas.

Mammography was performed using Fujifilm Amulet Innovality Digital Mammography System with a resolution of 5828×4728 pixels, including craniocaudal (CC) and mediolateral oblique (MLO) view. MRI was performed on a 3.0T scanner (GE SIGNA HDx) using a dedicated 8-channel bilateral breast coil. The imaging protocol included axial and sagittal T2- and T1-weighted sequences, and the DCE acquisition performed using the volume imaging for breast assessment (VIBRANT) sequence. The parameters were: repetition time= 5msec, echo time= 2msec, flip angle= 10°, slice thickness= 1.2mm, field of view= 34×34cm², matrix size= 416×416, temporal resolution= 90sec, and total scan time= 9min. The DCE series consisted of 6 frames: one pre-contrast and 5 post-contrast. The contrast agent, 0.1 mmol/kg body weight of gadopentetate dimeglumine (Magnevist; Bayer Schering Pharma), was injected after the pre-contrast images were acquired, with a flow rate of 2 mL/s followed by a flush of 20 mL saline.

All breast MRI examinations were performed at 3.0 T (GE medical systems, Discovery MR750) with the patient prone and by using a dedicated eight-channel surface breast coil. The standard imaging protocol included a localizing MRI sequence followed by an axial T2-weighted fat-suppressed sequence, an axial T1-weighted non–fat-suppressed sequence, an axial T1-weighted simultaneous fat-suppressed sequence performed before and six times after a rapid bolus injection, and a conventional contrast-enhanced sagittal T1-weighted fat-suppressed sequence.
For dynamic contrast-enhanced examination, contrast media (Magnevist, Bayer Schering Pharma, Germany) was administered immediately after the end of first (pre-contrast) sequence as a bolus intravenous injection at a dose of 0.1 mmol/kg and at the rate of 3.0 ml/s. All MRI sequences and parameters were listed on Table 1.Table 1

Breast MRI sequences and parameters.

Sequences	TR (ms)	TE (ms)	FOV (mm)	Matrix	Slice thickness (mm)	Slice distance (mm)
T1WI	420	7–41.8	400*400	320*256	5	1
T2WI	5540	85	320*320	320*256	5	1
Axial T1WI enhanced	3.9	1.1	360*360	320*320	1.4	—
Sagittal T1WI enhanced	4.9	1.2	240*240	256*224	1.8	—

Cardiac structure, function and thrombus were assessed from two CMR techniques, cardiac function by a SSFP technique and LGE using a 1.5 Tesla Gyroscan NT Philips scanner (Philip Medical Systems, Best, The Netherlands). Functional study was performed by the acquisition of images by a SSFP technique in Short-axis images were acquired every 8 mm throughout the entire LV. Long-axis images were obtained in standard 2-, 3-, and four-chamber orientations. Parameters for cardiac function were as follows: repetition time/echo time/number of excitations = 3.7 ms/1.8 ms/ 2, 390 × 312 mm field of view, 256 × 240 matrix, 1.52 × 1.21 reconstruction pixel, 8 mm slice thickness, and 70 flip angles.
For LGE imaging, images were acquired 15 to 20 min after intravenous injection of 0.2 mmol/kg gadolinium contrast agent (Magnevist, Bayer Schering Pharma, Berlin, Germany) with the following scanning parameters; echo time 1.25 ms, repetition time 4.1 ms, 15-degree flip angle, 303 × 384 mm field of view, 240 × 256 matrix, in-plane resolution 1.26 × 1.5 mm, slice thickness 8 mm and 1.5 Sensitivity-Encoding (SENSE) factor.
Additionally, long inversion time sequence was applied for increasing the accuracy for detection of LV thrombus, as mentioned in previous study [5 (link)].

Active stained gadolinium-enhanced ex vivo T2* MRI scans of the mouse brains were performed at age 18–21 weeks. Mice were sacrificed with an overdose injection of sodium pentobarbitone. An initial saline flush (1520 ml) was administered to the left ventricle, followed by a perfuse-fixation with 50 ml of 4% buffered formal-saline (Pioneer Research Chemicals, Colchester, UK) with 8 mM Gd-DTPA (Magnevist, Bayer-Schering Pharma, Newbury, UK), both at a flow rate of 3 ml/min. The decapitated intact skulls were then post-fixed in a solution of 4% formal saline and 8 mM Gd-GTPA at 4 °C for 9 weeks.
The ex vivo images were acquired following the protocol introduced by Cleary et al. (J.O. Cleary et al., 2011 (link)) to optimize the tissue contrast between different neuronal layers. The in-skull brains were imaged on a Varian 9.4T DirectDrive VNMRS system (Varian Inc., Palo Alto CA, USA) with a 26 mm quadrature volume coil (RAPID Biomedical GmbH, Wrzburg, Germany). 3D spoiled gradient echo sequence was used, with the following scanning parameters: TE = 4.03 ms, TR = 17 ms, FA = 52°, FOV = 20.48 × 13.04 × 13.04mm³, matrix = 512 × 326 × 326, averages = 6, scan time = 3 h. In addition, we used a multi-brain scanning protocol to image three brains at once to achieve multi-brain separation, orientation correction, and brain mask extraction (Powell et al., 2016 (link)).

All patients were imaged in a clinical 3.0 T scanner (Magnetom Verio, Siemens Healthcare, Erlangen, Germany) equipped with a 12-channel head coil using T1-weighted coronal and axial imaging and T2-weighted/FLAIR axial imaging. Postcontrast T1-weighted images were acquired after injection of either gadopentetate dimeglumine (Magnevist, Bayer Schering Pharma AG) or gadobenate dimeglumine (Multihance, BD), administered at a dose of 0.1 mmol/kg. The MR imaging protocol was as follows: T1-weighted images were acquired using an echo time (TE) 2.48 ms, a repetition time (TR) 300 ms, and voxel size 0.9 × 0.7 × 6 mm. T2-weighted FLAIR images were acquired using an inversion time of 2500 ms, TR 9000 ms, TE 90 ms, and voxel size of 0.9 × 0.9 × 6 mm.