Background and Purpose

Two challenges in clinical MRI are the slow image acquisition time and low image resolution compared to other clinical imaging technique such as CT. Clinical breast diffusion weighted imaging (DWI) is one of the most important application of MRI to detect lesion especially for different types of tumors. But it suffered from relative low imaging resolution and limited acquisition time especially with breast coils for signal receiving in which condition the patient would be in a prone position and feel uncomfortable. So the purpose of this study is to improve the image quality of diffusion weighted imaging (DWI) for clinical breast examination within a limited scanning time by using multi-band sense technique.

Materials and methods

For this work, this is an initial try to apply Philips multi-band sense in breast DWI with 7-channel breast coil, because the product of Philips was designed for brain imaging using 32-channel head coil. Two patients (Age 56 and 60 respectively) with breast lesions were scanned based on Ingenia CX 3.0T (Philips Healthcare, Best, The Netherlands) by using conventional DWI (CDWI) and multi-band sense DWI (MB-DWI) within a same scanning time. The protocol parameters for conventional DWI and multi-band sense DWI was listed in Table 1. The ADC maps corresponding to conventional DWI and multi-band sense DWI were also computed and compared.

Results

As shown in Figure 1. Even though we might find the signal-to-noise ratio is a little lower in multi-band sense DWI, The lesions of multi-band sense DWI images with b=1000 showed more details compared to conventional DWI, in which the lesion part showed sharp lesion edges and details information within the lesion. The ADC maps were almost the same with no obvious difference, and the ADC values were similar for the same imaging location.

Discussion

Multi-band sense is a technique for accelerating MRI scanning especially for EPI imaging which including different types of DWI and Bold-based fMRI. The underlying principle is the simultaneous multi-slice RF excitation and simultaneous multi-slice signal receiving, and then reconstructed the images and unfold the artifacts in image space. For multi-band sense technique, previous works focused on the brain imaging for accelerating the scanning or improve the image acquisition resolution in the brain imaging (EPI-based DWI and fMRI). In theory, the performance of multi-band sense demands much on coils design, so the most application of this technique was accompanied with 32, 64 or more-channels head coil and rarely used in body imaging especially for that there no enough clinical validations for this technique in clinical body application. The initial result of the multi-band sense in breast showed its advantage in body imaging with higher spatial resolution and detailed lesion, which might be helpful for clinical diagnosis. The potential difference in ADC value between CDWI and MB-DWI should be furtherly investigated. In the future work, we will also pay attention to the acceleration of this technique especially for those patients who cannot examination within a long time.

Conclusion

Multi-band sense could be applied for breast DWI imaging with high-quality images, which would be helpful for clinical diagnosis.

Acknowledgements

No acknowledgement found.