In Japan, 3T MRI was approved in 2003 under the Pharmaceutical Affairs Law. The spread of 3T equipment has since progressed due to improvements in hardware and software. On the other hand, the head and neck have many conditions that are disadvantageous for MRI usage due to factors such as involuntary movements, inhomogeneous magnetic fields due to the presence of metal prostheses and air spaces, and complex anatomy. As radial sampling is useful for motion compensation, it has been incorporated into many MR units. Static magnetic field correction is useful for reducing metal artifacts, which also leads to improvement of fat-suppressed imaging.
In this review, we summarize the effects of 3T equipment on image quality and methods for addressing problems specific to the maxillofacial region, and present specific clinical applications.
As an example of clinical application, we introduce contrast-enhanced T1-weighted imaging using compressed sensing and distortion-free diffusion-weighted imaging. Next, for assessing biochemical information, we introduce the estimation of fat fraction using the six-point Dixon method and trace components using the chemical exchange saturation transfer effect.
