Observational study on the incidence of nephrogenic systemic fibrosis in patients with renal impairment following gadoterate meglumine administration: the NSsaFe study.

BACKGROUND: Nephrogenic systemic fibrosis (NSF) is a rare life-threatening condition strongly associated with the administration of gadolinium-based contrast agents in patients with severe or endstage renal impairment. PURPOSE: To prospectively determine the incidence of NSF in patients with renal impairment after administration of gadoterate meglumine. STUDY TYPE: Prospective. POPULATION: In all, 540 patients with moderate, severe, or endstage renal impairment, scheduled to undergo a routine contrast-enhanced MRI with gadoterate meglumine. Mean age was 69.7 ± 12.7 years (range: 21-95) with 58.4% of males. FIELD STRENGTH/SEQUENCE: 1.5T or 3.0T, sequence according to each site practice. ASSESSMENT: Medical history, indication(s) for current MRI and adverse events were recorded for each patient. Patients were followed up over 2 years after administration with three visits separated by at least 3 months to detect any signs/symptoms suggestive of NSF. STATISTICAL TESTS: Descriptive. RESULTS: Renal impairment was graded as moderate for 69.4% of patients, severe for 16.0% and endstage for 12.1%; 2.6% had undergone a kidney transplant. Estimated glomerular filtration rate ranged from 4 to 59 mL/min/1.73 m2 except one value of 74 mL/min/1.73 m2 in a patient with kidney transplant. Central nervous system exploration was the main MRI indication (34.7%) and mean dose injected was 0.22 ± 0.09 mL/kg. Overall, 446 patients (82.6%) attended at least one follow-up visit and completed the NSF questionnaire and 329 (60.9%) attended the 2-year visit. No suspicion of NSF was reported in all 446 patients, including 119 patients with severe or endstage renal impairment. No deaths and no adverse events were reported during the MRI examination and the usual period of follow-up after gadoterate meglumine administration. DATA CONCLUSION: No cases of NSF were observed in the 446 patients with moderate to endstage renal impairment followed up over a maximum of 2 years after injection of gadoterate meglumine. LEVEL OF EVIDENCE: 2 Technical Efficacy Stage: 4 J. Magn. Reson. Imaging 2020;51:607-614.

Assessing the Risks Associated with MRI in Patients with a Pacemaker or Defibrillator.

BACKGROUND: The presence of a cardiovascular implantable electronic device has long been a contraindication for the performance of magnetic resonance imaging (MRI). We established a prospective registry to determine the risks associated with MRI at a magnetic field strength of 1.5 tesla for patients who had a pacemaker or implantable cardioverter-defibrillator (ICD) that was "non-MRI-conditional" (i.e., not approved by the Food and Drug Administration for MRI scanning). METHODS: Patients in the registry were referred for clinically indicated nonthoracic MRI at a field strength of 1.5 tesla. Devices were interrogated before and after MRI with the use of a standardized protocol and were appropriately reprogrammed before the scanning. The primary end points were death, generator or lead failure, induced arrhythmia, loss of capture, or electrical reset during the scanning. The secondary end points were changes in device settings. RESULTS: MRI was performed in 1000 cases in which patients had a pacemaker and in 500 cases in which patients had an ICD. No deaths, lead failures, losses of capture, or ventricular arrhythmias occurred during MRI. One ICD generator could not be interrogated after MRI and required immediate replacement; the device had not been appropriately programmed per protocol before the MRI. We observed six cases of self-terminating atrial fibrillation or flutter and six cases of partial electrical reset. Changes in lead impedance, pacing threshold, battery voltage, and P-wave and R-wave amplitude exceeded prespecified thresholds in a small number of cases. Repeat MRI was not associated with an increase in adverse events. CONCLUSIONS: In this study, device or lead failure did not occur in any patient with a non-MRI-conditional pacemaker or ICD who underwent clinically indicated nonthoracic MRI at 1.5 tesla, was appropriately screened, and had the device reprogrammed in accordance with the prespecified protocol. (Funded by St. Jude Medical and others; MagnaSafe ClinicalTrials.gov number, NCT00907361 .).

Reversal of CT hypodensity after acute ischemic stroke.

We report a man admitted to the hospital after sustaining an ischemic stroke, with a return to isodensity on repeat computed tomography (CT) scan noted at day 9 of his hospital stay. This finding, known as the "fogging effect," has never been noted so early in a patient's course on CT imaging. ABBREVIATIONS: CTcomputed tomographyMRImagnetic resonance imaging.