Opportunities and Challenges of 7 Tesla Magnetic Resonance Imaging: A Review.

The desire to achieve clinical ultra-high magnetic resonance imaging (MRI) systems stems from the fact that higher field strength leads to higher signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and spatial resolution. During last few years 7T MRI systems have become a quasi standard for ultra-high field MRI (UhFMRI) systems. This review presents a detailed account of opportunities and challenges associated with a clinical 7T MRI system for cranial and extracranial imaging. As with all of the previous transitions to higher field strengths, the switch from high to UhFMRI is not easy. The engineering and scientific community have to overcome challenges like magnetic field inhomogeneity, patient safety and comfort issues, and cost and related problems in order to achieve a clinically viable UhFMRI system. In addition, a large number of clinical studies are still required to show the improvements in quality of diagnostics that would come with 7T MRI, in order to bring such a research tool to the clinic.