Magnetic resonance imaging and spectroscopy (MRI/MRS) at 7T represents an exciting advance in MR technology, with intriguing possibilities to enhance image spatial, spectral, and contrast resolution. To ensure the safe use of this technology while still harnessing its potential, clinical staff and researchers need to be cognizant of some safety concerns arising from the increased magnetic field strength and higher Larmor frequency. The higher static magnetic fields give rise to enhanced transient bioeffects and an increased risk of adverse incidents related to electrically conductive implants. Many technical challenges remain and the continuing rapid pace of development of 7T MRI/MRS is likely to present further challenges to ensuring safety of this technology in the years ahead. The recent regulatory clearance for clinical diagnostic imaging at 7T will likely increase the installed base of 7T systems, particularly in hospital environments with little prior ultrahigh‐field MR experience. Informed risk/benefit analyses will be required, particularly where implant manufacturer‐published 7T safety guidelines for implants are unavailable. On behalf of the International Society for Magnetic Resonance in Medicine, the aim of this article is to provide a reference document to assist institutions developing local institutional policies and procedures that are specific to the safe operation of 7T MRI/MRS. Details of current 7T technology and the physics underpinning its functionality are reviewed, with the aim of supporting efforts to expand the use of 7T MRI/MRS in both research and clinical environments. Current gaps in knowledge are also identified, where additional research and development are required.Level of Evidence 5Technical Efficacy 2J. MAGN. RESON. IMAGING 2021;53:333–346.

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BACKGROUND AND PURPOSE: MR imaging is not routinely used to image the extracranial facial nerve. The purpose of this study was to determine the extent to which this nerve can be visualized with a CISS sequence and to determine the feasibility of using that sequence for locating the nerve relative to tumor. MATERIALS AND METHODS:Thirty-two facial nerves in 16 healthy subjects and 4 facial nerves in 4 subjects with parotid gland tumors were imaged with an axial CISS sequence protocol that included 0.8-mm isotropic voxels on a 3T MR imaging system with a 64-channel head/neck coil. Four observers independently segmented the 32 healthy subject nerves. Segmentations were compared by calculating average Hausdorff distance values and Dice similarity coefficients. RESULTS:The primary bifurcation of the extracranial facial nerve into the superior temporofacial and inferior cervicofacial trunks was visible on all 128 segmentations. The mean of the average Hausdorff distances was 1.2 mm (range, 0.3-4.6 mm). Dice coefficients ranged from 0.40 to 0.82. The relative position of the facial nerve to the tumor could be inferred in all 4 tumor cases. CONCLUSIONS:The facial nerve can be seen on CISS images from the stylomastoid foramen to the temporofacial and cervicofacial trunks, proximal to the parotid plexus. Use of a CISS protocol is feasible in the clinical setting to determine the location of the facial nerve relative to tumor.

Ultra‐high‐field 7.0 Tesla (T) MRI offers substantial gains in signal‐to‐noise ratio (SNR) over 3T and 1.5T, but for over two decades has remained a research tool, while 3T scanners have achieved widespread clinical use. This much slower translation of 7T relates to daunting technical challenges encountered in ultra‐high‐field human MR imaging. The recent introduction of United States Food and Drug Administration (FDA)‐approved clinical 7T scanners promises to be a watershed for many 7T neuroimaging applications, including epilepsy imaging. The high SNR of 7T allows clinical imaging of fine neuroanatomic detail at unprecedented spatial resolution, helping with detection and differentiation of subtle, potentially treatable lesions undetectable or suboptimally assessed at 3T. The accompanying research paper reports our group's analysis of 7T MRI efficacy in epilepsy treatment planning. Here, we introduce the technical background and clinical approach we currently use, in order to assist clinical epileptologists and neuroimagers contemplating, creating, or referring patients to a clinical 7T epilepsy imaging service. We describe a tiered epilepsy imaging strategy and protocols designed to optimize 7T value and work around signal intensity variation and signal loss artifacts, which remain significant challenges to full exploitation of 7T clinical value. We describe FDA‐approved techniques for mitigating these artifacts and briefly outline techniques currently under development, but not yet FDA approved. Finally, we discuss the major issues in 7T patient safety and toleration, outlining their physical causes and effects on workflow, and provide references to more comprehensive technical reviews for readers seeking greater technical detail.

on behalf of the ISMRM Safety CommitteeThis article is intended to provide guidelines for the minimum level of safety and operational knowledge that an MR system operator should exhibit in order to safely perform an MR procedure in a human subject in a research setting. This article represents the position of the International Society for Magnetic Resonance in Medicine (ISMRM) regarding this important topic and was developed by members of this society's MR Safety Committee. DESCRIPTIONTHE CONTENT of this article is intended to provide an outline of the guidelines for the minimum level of safety and operational knowledge that a magnetic resonance (MR) system operator should exhibit in order to safely scan a human subject in a research setting. RATIONALEThis article represents the position of the International Society of Magnetic Resonance in Medicine (ISMRM) regarding this important topic and was developed by members of this society's MR Safety Committee.These guidelines are meant to specifically focus on potential MR safety-related matters to ensure that operation of the research facility is carried out in a safe manner for the subject undergoing the MR procedure, associated researchers, and healthcare providers. All the requirements for the MR system operator relating to the quality, efficiency, and/or efficacy of the research to be performed must be defined by the principal investigator responsible for the specific research project under consideration.Furthermore, these guidelines cover the minimum requirements to ensure basic safety, and do not cover other issues related to invasive procedures, interventional procedures, or the administration of MRI contrast agents, which require special consideration and are beyond the scope of this article.Finally, this article only provides an outline for the minimum standards that MR sites should consider in order to set up their MR safety plan; this article therefore does not intend to mandate how MR system operators obtain the necessary education and training but rather establishes the baseline of MR safety topics in which the operators must be proficient. Therefore, it is the individual site's responsibility to define how, by whom, and by what sources the MR system operator obtains the necessary safety-related knowledge, acknowledging that specific details and requirements may vary between centers, countries, etc. DEFINITIONS AND RESPONIBILITIESGiven the difference in existing nomenclature and to avoid any possible misunderstanding, the