The use of 7T MRI in multiple sclerosis: review and consensus statement from the North American Imaging in Multiple Sclerosis Cooperative.

The use of ultra-high-field 7-Tesla (7T) MRI in multiple sclerosis (MS) research has grown significantly over the past two decades. With recent regulatory approvals of 7T scanners for clinical use in 2017 and 2020, the use of this technology for routine care is poised to continue to increase in the coming years. In this context, the North American Imaging in MS Cooperative (NAIMS) convened a workshop in February 2023 to review the previous and current use of 7T technology for MS research and potential future research and clinical applications.

From strength to precision: A systematic review exploring the clinical utility of 7-Tesla magnetic resonance imaging in abdominal imaging.

Background: After approval for clinical use in 2017 early investigations of ultra-high-field abdominal magnetic resonance imaging (MRI) have demonstrated the feasibility as well as diagnostic capabilities of liver, kidney, and prostate MRI at 7-Tesla. However, the elevation of the field strength to 7-Tesla not only brought advantages to abdominal MRI but also presented considerable challenges and drawbacks, primarily stemming from heightened artifacts and limitations in Specific Absorption Rate, Furthermore, evidence in the literature is relatively scarce concerning human studies in comparison to phantom/animal studies which necessitates an investigation into the evidence so far in humans and summarizing all relevant evidence.

Aim: To offer a comprehensive overview of current literature on clinical abdominal 7T MRI that emphasizes current trends, details relevant challenges, and provides a concise set of potential solutions.

Evaluation of 3-dimensional stereotactic surface projection rendering of arterial spin labeling data in a clinical cohort.

Background And Purpose: To assess the feasibility of 3-dimensional stereotactic surface projection (3D-SSP) as applied to arterial spin labeling (ASL) in a clinical pilot study.

Methods: A retrospective sample of 10 consecutive patients who underwent ASL as part of a clinically indicated MR examination was collected during this pilot study. Five additional subjects with normal cerebral perfusion served as a control group.

Motion resilience of the balanced steady-state free precession geometric solution.

Purpose: Many MRI sequences are sensitive to motion and its associated artifacts. The linearized geometric solution (LGS), a balanced steady-state free precession (bSSFP) off-resonance signal demodulation technique, is evaluated with respect to motion artifact resilience.

Theory And Methods: The mechanism and extent of LGS motion artifact resilience is examined in simulated, flow phantom, and in vivo clinical imaging.

MR Imaging Safety Events: Analysis and Improvement.

Multiple factors, including tight patient scheduling, complex electronic medical records, and increasing numbers of implanted devices, increase chances of MR imaging safety event occurrence. Several MR imaging safety incidents are described in this article, including the safety conditions and other factors that contributed to the events. MR imaging safety policy and procedural improvements that address these are also described.

Making Magnets More Attractive: Physics and Engineering Contributions to Patient Comfort in MRI.

Patient comfort is an important factor of a successful magnetic resonance (MR) examination, and improvements in the patient's MR scanning experience can contribute to improved image quality, diagnostic accuracy, and efficiency in the radiology department, and therefore reduced cost. Magnet designs that are more open and accessible, reduced auditory noise of MR examinations, light and flexible radiofrequency (RF) coils, and faster motion-insensitive imaging techniques can all significantly improve the patient experience in MR imaging. In this work, we review the design, development, and implementation of these physics and engineering approaches to improve patient comfort.

Practical Considerations for Radiologists in Implementing a Patient-friendly MRI Experience.

For many patients, numerous unpleasant features of the magnetic resonance imaging (MRI) experience such as scan duration, auditory noise, spatial confinement, and motion restrictions can lead to premature termination or low diagnostic quality of imaging studies. This article discusses practical, patient-oriented considerations that are helpful for radiologists contemplating ways to improve the MRI experience for patients. Patient friendly scanner properties are discussed, with an emphasis on literature findings of effectiveness in mitigating patient claustrophobia, other anxiety, or motion and on reducing scan incompletion rates or need for sedation.

ACR guidance document on MR safe practices: Updates and critical information 2019.

The need for a guidance document on MR safe practices arose from a growing awareness of the MR environment's potential risks and adverse event reports involving patients, equipment, and personnel. Initially published in 2002, the American College of Radiology White Paper on MR Safety established de facto industry standards for safe and responsible practices in clinical and research MR environments. The most recent version addresses new sources of risk of adverse events, increases awareness of dynamic MR environments, and recommends that those responsible for MR medical director safety undergo annual MR safety training.

Safety Considerations of 7-T MRI in Clinical Practice.

Although 7-T MRI has recently received approval for use in clinical patient care, there are distinct safety issues associated with this relatively high magnetic field. Forces on metallic implants and radiofrequency power deposition and heating are safety considerations at 7 T. Patient bioeffects such as vertigo, dizziness, false feelings of motion, nausea, nystagmus, magnetophosphenes, and electrogustatory effects are more common and potentially more pronounced at 7 T than at lower field strengths.

Avoiding MRI-Related Accidents: A Practical Approach to Implementing MR Safety.

MRI is a ubiquitous medical imaging technology typically using superconductivity to generate a strong, homogeneous, and generally ceaseless magnetic field. MRI and its magnetic field pose many safety hazards, including magnetic forces on metals, tissue heating and burns, nerve stimulation, bioeffects, acoustic noise, and contrast agent complications. The primary concern is that a wide variety of patients, staff members, technologists, and physicians can approach the incessant magnetic field, creating great potential for accidents that could occur if metals from the environment, adornments, implants, and other unintended sources are also present in or near the field.

MRI sport-specific pulley imaging.

Objective: We aim to create a novel MRI methodology that employs sport-specific stress views for imaging finger pulley injuries in the evaluation of post-operative healing effectiveness. The goal is to measure the bone to tendon distance (BTD), which is the current standard for determining pulley injuries.

Materials And Methods: The athlete was imaged in a crimp-grip stressed position to emulate sport-specific biomechanics.

Combined geometric and algebraic solutions for removal of bSSFP banding artifacts with performance comparisons.

Purpose: Balanced steady state free precession (bSSFP) imaging suffers from off-resonance artifacts such as signal modulation and banding. Solutions for removal of bSSFP off-resonance dependence are described and compared, and an optimal solution is proposed.

Theory And Methods: An Algebraic Solution (AS) that complements a previously described Geometric Solution (GS) is derived from four phase-cycled bSSFP datasets.

Toward Quantifying the Prevalence, Severity, and Cost Associated With Patient Motion During Clinical MR Examinations.

Purpose: To assess the prevalence, severity, and cost estimates associated with motion artifacts identified on clinical MR examinations, with a focus on the neuroaxis.

Methods: A retrospective review of 1 randomly selected full calendar week of MR examinations (April 2014) was conducted for the detection of significant motion artifacts in examinations performed at a single institution on 3 different MR scanners. A base-case cost estimate was computed from recently available institutional data, and correlated with sequence time and severity of motion artifacts.

Banding artifact removal for bSSFP imaging with an elliptical signal model.

Purpose: Balanced steady-state free precession (bSSFP) imaging has broad clinical applications by virtue of its high time efficiency and desirable contrast. Unfortunately, banding artifact is often seen as a result of signal modulation due to B0 inhomogeneity. This study aims to develop an effective method for banding artifact suppression.

In vivo measurement of the hypoxia marker EF5 in Shionogi tumours using (19)F magnetic resonance spectroscopy.

Purpose: (19)F magnetic resonance spectroscopy (MRS) was used to non-invasively detect EF5 [2-(2-nitro-1H-imidazol-1-yl)-N-(2,2,3,3,3-pentafluoropropyl) acetamide] adducts in the Shionogi tumour model of prostate cancer to evaluate hypoxia.

Material And Methods: (19)F MRS signal of EF5 in Shionogi mouse tumours was acquired using a 2 cm diameter solenoid volume coil with a 7.05 T Bruker scanner.