Purpose: To determine the incidence of nephrogenic systemic fibrosis (NSF) in patients with severe chronic kidney disease (CKD) who underwent a uniform protocol for contrast material–enhanced magnetic resonance (MR) imaging with a gadolinium-based contrast agent (GBCA).

Materials and Methods: This retrospective, single-center, institutional review board–approved, HIPAA-compliant study included 3819 patients with severe (stage 4 or 5) CKD who underwent gadobenate dimeglumine–enhanced MR imaging as part of a preoperative evaluation for potential renal transplantation from January 2008 to February 2014. After undergoing contrast-enhanced MR imaging, patients were assessed for NSF by means of clinical follow-up, including a full integumentary examination, with a minimum of 6 months between administration of the GBCA and clinical skin examination. Suspicious skin lesions were sampled with deep punch biopsy, and results of pathologic examination were reviewed and categorized. In addition, a search of the institution’s pathology database during the time of the study was performed to identify any additional patients with NSF. The proportion of subjects who developed NSF after the administration of gadobenate dimeglumine was calculated, and Clopper-Pearson 95% confidence intervals were determined by using binomial proportions.

Results: The average length of follow-up for the patient population was 501 days (range, 186–2121 days). A total of 219 biopsies were performed, and none of the 3819 patients developed NSF after administration of gadobenate dimeglumine, resulting in a proportion of zero; the exact upper bound of 95% confidence interval was 0.000965 (0.0965%).

Conclusion: None of the 3819 patients with severe CKD developed NSF after undergoing gadobenate dimeglumine–enhanced MR imaging, which suggests that this GBCA may be safely administered in patients with severe CKD, with an immeasurable risk for the subsequent development of NSF.

The number of patients receiving cochlear implants and auditory brainstem implants for severe to profound sensorineural hearing loss has rapidly increased. These implants consist of an internal component implanted between the skull and the temporal scalp and an external removable speech processor unit. A small magnet within the internal component is commonly used to hold the external speech processor unit in place. Several cochlear implant models have recently received U.S. Food and Drug Administration and European Economic Area regulatory approval to allow magnetic resonance (MR) imaging examinations to be performed under certain specified conditions. The small internal magnet presents a challenge for imaging of the head and neck near the implant, creating a nonlinear magnetic field inhomogeneity and significant MR imaging artifacts. Fat-saturation failures and susceptibility artifacts severely degrade image quality. Typical artifacts at diffusion-weighted imaging and accelerated imaging are exacerbated. Each examination may require impromptu adjustments to allow visualization of the tissue or contrast of interest. Patients may also be quite uncomfortable during the examination, as a result of either imposed magnetic forces or a tight head wrap that is often applied to minimize internal magnet movement. Translational forces and torque sometimes displace the implanted magnet even when a head wrap is used. Diseases such as neurofibromatosis type 2 that are associated with bilateral vestibular schwannomas and hearing loss often require lifelong tumor surveillance with MR imaging. A collaborative team of radiologists, technologists, and/or medical physicists or MR imaging scientists, armed with strategies to mitigate artifacts near implanted magnets, can customize the examination for better visualization of tissue and consistent comparison examinations over time.