7T: Physics, safety, and potential clinical applications.

Area of Science:

• Medical Imaging
• Biophysics
• Radiology

Background:

• Over 60 ultrahigh-field (UHF) magnetic resonance imaging (MRI) systems operating at 7 Tesla (7T) or higher are installed globally.
• Significant technical and methodological advancements have addressed challenges in radiofrequency (RF) signal homogenization for UHF MRI.
• Development of specialized RF coil arrays has expanded UHF MRI applications beyond the brain to body imaging.

Purpose of the Study:

• To provide an overview of the physical challenges associated with 7T UHF MRI.
• To discuss recent technical solutions and safety concepts for clinical application.
• To highlight clinically oriented studies demonstrating the capabilities of 7T MRI and MR spectroscopy (MRS) for diagnostics.

Main Methods:

• Review of technical developments in UHF MRI hardware and methodology.
• Discussion of safety testing protocols and concepts for implants at 7T.
• Synthesis of findings from recent clinical studies utilizing 7T MRI and MRS.

Main Results:

• 7T MRI and MR spectroscopy (MRS) show significant potential for clinical diagnostics.
• Technical solutions have overcome previous limitations in RF signal homogeneity.
• Safety testing and concepts are crucial for the clinical translation of 7T MRI.

Conclusions:

• Ultrahigh-field MRI at 7T is established for clinical research, offering advanced diagnostic capabilities.
• Ongoing research focuses on overcoming technical hurdles and ensuring safety for broader clinical adoption.
• 7T MRI is expanding its application spectrum from brain to body imaging.