Synopsis

Keywords: Image acquisition: Fast imaging, Transferable skills: Safety

We will discuss various ways to accelerate MRI scans in clinical settings such as partial Fourier, parallel imaging, and compressive sensing. We will elaborate on the main advantages and disadvantages of each approach. Then, we will explore some of the safety concerns in MRI that impact scan duration, in order to uncover indirect ways to reduce scan time further. We will expand the safety discussion towards the presence of implants, discussing implant safety definitions and their implications for scanning. We will also examine the effect of metallic implants on image quality and describe some techniques to reduce such effects.

Magnetic Resonance Imaging (MRI) presents a trade off in almost all imaging scenarios, between high-quality images of soft tissue and scan time. While reduced scan time is very desirable in many cases, one of the settings where it may become crucial is trauma (1-8). The lack of another few minutes to spare and the critical status the patient might be in necessitate the fastest and the most reliable methods.

This talk will start with a discussion on various approaches that can be used to accelerate imaging, including but not limited to partial Fourier (9), parallel imaging (10,11), simultaneous multi-slice imaging (12) and compressive sensing (13,14). We will elaborate on the main benefits and pitfalls of each method. Then, we will explore some of the safety concerns in MRI that impact scan duration to provide further options for accelerated imaging (15). We will expand the safety discussion towards concerns that relate to the presence of implants. We will discuss device / implant safety definitions and their implications for scanning (16,17). We will also examine the effect of implants on image quality and describe some techniques that can be used to reduce such effects (18).

The main learning objectives for this talk are:
- What settings / options on the scanner have a direct impact towards reducing scan time and at what cost?
- What settings / options on the scanner reduce the specific absorption rate and thereby indirectly enable further reductions in scan time, and what are the disadvantages of these options / settings?
- What are the image quality and safety implications of implants, devices and foreign bodies?

Acknowledgements

No acknowledgement found.

References

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