Contrast-induced encephalopathy-neuroimaging findings and clinical relevance.

Contrast-induced encephalopathy (CIE) is a rare encephalopathic condition after the administration of a contrast agent. The diagnosis of CIE is challenging because of the heterogeneity and non-specificity of the clinical presentation. The clinical course is usually favorable with full recovery within 48-72 h in most patients, although comorbidity is of relevance and contributes to the clinical outcome. It is expected that the incidence of CIE is currently increasing, due to an increase in endovascular and diagnostic imaging procedures using iodinated contrast. It is important to include CIE in the differential diagnosis when patients deteriorate during, or immediately after, contrast administration, even when only a small amount of non-ionic contrast agent is used. When CIE is considered to be the most likely explanation for the clinical symptoms, it is advised to refrain from unnecessary additional contrast studies such as angiography or perfusion CT.

Deep learning-based reconstruction may improve non-contrast cerebral CT imaging compared to other current reconstruction algorithms.

OBJECTIVES: To evaluate image quality and reconstruction times of a commercial deep learning reconstruction algorithm (DLR) compared to hybrid-iterative reconstruction (Hybrid-IR) and model-based iterative reconstruction (MBIR) algorithms for cerebral non-contrast CT (NCCT). METHODS: Cerebral NCCT acquisitions of 50 consecutive patients were reconstructed using DLR, Hybrid-IR and MBIR with a clinical CT system. Image quality, in terms of six subjective characteristics (noise, sharpness, grey-white matter differentiation, artefacts, natural appearance and overall image quality), was scored by five observers. As objective metrics of image quality, the noise magnitude and signal-difference-to-noise ratio (SDNR) of the grey and white matter were calculated. Mean values for the image quality characteristics scored by the observers were estimated using a general linear model to account for multiple readers. The estimated means for the reconstruction methods were pairwise compared. Calculated measures were compared using paired t tests. RESULTS: For all image quality characteristics, DLR images were scored significantly higher than MBIR images. Compared to Hybrid-IR, perceived noise and grey-white matter differentiation were better with DLR, while no difference was detected for other image quality characteristics. Noise magnitude was lower for DLR compared to Hybrid-IR and MBIR (5.6, 6.4 and 6.2, respectively) and SDNR higher (2.4, 1.9 and 2.0, respectively). Reconstruction times were 27 s, 44 s and 176 s for Hybrid-IR, DLR and MBIR respectively. CONCLUSIONS: With a slight increase in reconstruction time, DLR results in lower noise and improved tissue differentiation compared to Hybrid-IR. Image quality of MBIR is significantly lower compared to DLR with much longer reconstruction times. KEY POINTS: • Deep learning reconstruction of cerebral non-contrast CT results in lower noise and improved tissue differentiation compared to hybrid-iterative reconstruction. • Deep learning reconstruction of cerebral non-contrast CT results in better image quality in all aspects evaluated compared to model-based iterative reconstruction. • Deep learning reconstruction only needs a slight increase in reconstruction time compared to hybrid-iterative reconstruction, while model-based iterative reconstruction requires considerably longer processing time.

Development of a model to predict vestibular schwannoma growth: An opportunity to introduce new wait and scan strategies.

OBJECTIVES: To develop a prediction model to predict vestibular schwannoma (VS) growth for patients in a wait and scan (W&S) strategy. DESIGN: Retrospective cohort study. SETTING: Tertiary hospital (Radboud university medical center, Nijmegen, the Netherlands). PARTICIPANTS: Patients with unilateral VS, entering a W&S strategy and at least one follow-up MRI available. Data on demographics, symptoms, audiometry and MRI characteristics at time of diagnosis were collected from medical records. MAIN OUTCOME MEASURES: Following multiple imputation, a multivariable Cox regression model was used to select variables, using VS growth (≥2 mm) as outcome. Decision curve analyses (DCA) were performed to compare the model to the current strategy. RESULTS: Of 1217 analysed VS patients, 653 (53.7%) showed growth during follow-up. Balance complaints (HR 1.57 (95% CI: 1.31-1.88)) and tinnitus complaints in the affected ear (HR 1.36 (95% CI: 1.15-1.61)), Koos grade (Koos 1 is reference, Koos 2 HR 1.03 (95% CI: 0.80-1.31), Koos 3 HR 1.55 (95% CI: 1.16-2.06), Koos 4 HR 2.18 (95% CI: 1.60-2.96)), time since onset of symptoms (IQR HR 0.83 (95% CI: 0.77-0.88) and intrameatal diameter on MRI (IQR HR 1.67 (95% CI: 1.42-1.96)) were selected as significant predictors. The model's discrimination (Harrell's C) was 0.69 (95% CI: 0.67-0.71), and calibration was good. DCA showed that the model has a higher net benefit than the current strategy for probabilities of VS growth of >12%, 15% and 21% for the first consecutive 3 years, respectively. CONCLUSIONS: Patients with balance and tinnitus complaints, a higher Koos grade, short duration of symptoms and a larger intrameatal diameter at time of diagnosis have a higher probability of future VS growth. After external validation, this model may be used to inform patients about their prognosis, individualise the W&S strategy and improve (cost-)effectiveness.

Impact of optimizing diagnostic workup and reducing the time to treatment in head and neck cancer.

BACKGROUND: Timely and efficient diagnostic workup of patients with head and neck cancer (HNC) is challenging. This observational study describes the implementation of an optimized multidisciplinary oncological diagnostic workup for patients with HNC and its impact on diagnostic and treatment intervals, survival, costs, and patient satisfaction. METHODS: All patients with newly diagnosed HNC who underwent staging and treatment at the Radboud University Medical Center were included. Conventional workup (CW) in 2009 was compared with the fast-track, multidisciplinary, integrated care program, that is, optimized workup (OW), as implemented in 2014. RESULTS: The study included 486 patients with HNC (218 with CW and 268 with OW). The time-to-treatment interval was significantly lower in the OW cohort than the CW cohort (21 vs 34 days; P < .0001). The 3-year overall survival rate was 12% higher after OW (72% in the CW cohort vs 84% in the OW cohort; P = .002). After correction for confounders, the 3-year risk of death remained significantly lower in the OW cohort (hazard ratio, 1.73; 95% confidence interval, 1.14-2.63; P = .010). Total diagnostic costs were comparable in the 2 cohorts. The general satisfaction score, as measured with the Consumer Quality Index for Oncological Care, was significantly better in a matched OW group than the CW group (9.1 vs 8.5; P = .007). CONCLUSIONS: After the implementation of a fast-track, multidisciplinary, integrated care program, the time-to-treatment interval was significantly reduced. Overall survival and patient satisfaction increased significantly, whereas costs did not change. This demonstrates the impact and improved quality of care achieved by efficiently organizing the diagnostic phase of HNC management.

Assessment of surgical tumor-free resection margins in fresh squamous-cell carcinoma resection specimens of the tongue using a clinical MRI system.

BACKGROUND: Current intraoperative methods of visual inspection and tissue palpation by the surgeon, and frozen section analysis cannot reliably prevent inadequate surgical margins in patients treated for oral squamous-cell carcinoma (OSCC). This study assessed feasibility of MRI for the assessment of surgical resection margins in fresh OSCC specimens. METHODS: Ten consecutive tongue specimens containing OSCC were scanned using 3 T clinical whole-body MRI. Two radiologists independently annotated OSCC location and minimal tumor-free margins. Whole-mount histology was the reference standard. RESULTS: The positive predictive values (PPV) and negative predictive values (NPV) for OSCC localization were 96% and 75%, and 87% and 79% for reader 1 and 2, respectively. The PPV and NPV for identification of margins <5 mm were 38% and 91%, and 5% and 87% for reader 1 and 2, respectively. CONCLUSIONS: MRI accurately localized OSCC with high inter-reader agreement in fresh OSCC specimens, but it seemed not yet feasible to accurately assess the surgical margin status.

In search of the most cost-effective monitoring strategy for vestibular schwannoma: A decision analytical modelling study.

OBJECTIVES: To assess the cost-effectiveness of frequently used monitoring strategies for vestibular schwannoma (VS). DESIGN: A state transition model was developed to compare six monitoring strategies for patients with VS: lifelong annual monitoring; annual monitoring for the first 10 years after diagnosis; scanning at 1-5, 7, 9, 12, 15 years after diagnosis and subsequently every 5 years; a personalised monitoring strategy for small and large tumours; scanning at 1, 2 and 5 years after diagnosis and no monitoring. Input data were derived from literature and expert opinion. Quality-adjusted life years (QALYs) and healthcare costs of each strategy were modelled over lifetime. Net monetary benefits (NMBs) were calculated to determine which strategy provided most value for money. Sensitivity analyses were performed to address uncertainty. RESULTS: Omitting monitoring is least effective with 18.23 (95% CI 16.84-19.37) QALYs per patient, and lifelong annual monitoring is most effective with 18.66 (95% CI 17.42-19.65) QALYs. Corresponding costs were €6526 (95% CI 5923-7058) and €9429 (95% CI 9197-9643) per patient, respectively. Lifelong annual monitoring provided the best value with a NMB of €363 765 (339 040-383 697), but the overall probability of being most cost-effective compared to the other strategies was still only 23%. Sensitivity analysis shows that there is large uncertainty in the effectiveness of all strategies, with largely overlapping 95% confidence intervals for all strategies. CONCLUSIONS: Due to the largely overlapping 95% confidence intervals of all monitoring strategies for VS, it is unclear which monitoring strategy provides most value for money at this moment.

Brain CT perfusion improves intracranial vessel occlusion detection on CT angiography.

BACKGROUND AND PURPOSE: To evaluate whether brain CT perfusion (CTP) aids in the detection of intracranial vessel occlusion on CT angiography (CTA) in acute ischemic stroke. MATERIALS AND METHODS: Medical-ethical committee approval of our hospital was obtained and informed consent was waived. Patients suspected of acute ischemic stroke who underwent non-contrast CT(NCCT), CTA and whole-brain CTP in our center in the year 2015 were included. Three observers with different levels of experience evaluated the imaging data of 110 patients for the presence or absence of intracranial arterial vessel occlusion with two strategies. In the first strategy, only NCCT and CTA were available. In the second strategy, CTP maps were provided in addition to NCCT and CTA. Receiver-operating-characteristic (ROC) analysis was used for the evaluation of diagnostic accuracy. RESULTS: Overall, a brain perfusion deficit was scored present in 87-89% of the patients with an intracranial vessel occlusion, more frequently observed in the anterior than in the posterior circulation. Performance of intracranial vessel occlusion detection on CTA was significantly improved with the availability of CTP maps as compared to the first strategy (P=0.023), due to improved detection of distal and posterior circulation vessel occlusions (P-values of 0.032 and 0.003 respectively). No added value of CTP was found for intracranial proximal vessel occlusion detection, with already high accuracy based on NCCT and CTA alone. CONCLUSION: The performance of intracranial vessel occlusion detection on CTA was improved with the availability of brain CT perfusion maps due to the improved detection of distal and posterior circulation vessel occlusions.

Toxic Leukoencephalopathy Presenting as Lethal Catatonia.

INTRODUCTION: Catatonia is a syndrome that can present in different forms and can occur in multiple psychiatric and somatic conditions. This case report describes lethal catatonia caused by delayed toxic leukoencephalopathy after excessive use of cocaine and methadone. The characteristic radiographic imaging and biphasic course are discussed. CASE REPORT: A 54-year-old woman was presented unconsciously at the emergency department after intoxication with methadone and cocaine. After initial recovery, her condition deteriorated unexpectedly, resulting in lethal catatonia. Magnetic resonance imaging (MRI) showed hyperintense white matter abnormalities and diffusion restriction, evident for leukoencephalopathy. DISCUSSION: Catatonia can develop in multiple psychiatric and somatic diseases, including toxic leukoencephalopathy. A biphasic course and specific MRI findings are characteristics for delayed toxic leukoencephalopathy, due to intoxication with drugs.

The interobserver agreement in the detection of recurrent HNSCC using MRI including diffusion weighted MRI.

INTRODUCTION: For the detection of local recurrences of head and neck squamous cell carcinomas (HNSCC) after (chemo)radiation, diagnostic imaging is generally performed. Diffusion weighted magnetic resonance imaging (DW-MRI) has been proven to be able to adequately diagnose the presence of cancer. However evaluation of DW-MR images for recurrences is difficult and could be subject to individual interpretation. AIM: To determine the interobserver agreement, intraobserver agreement and influence of experience of radiologists in the assessment of DW-MRI in patients clinically suspected of local recurrent HNSCC after (chemo)radiation. METHODS: Ten experienced head and neck radiologists assessed follow-up MRI including DW-MRI series of 10 patients for the existence of local recurrence on a two point decision scale (local recurrence or local control). Patients were clinically suspected for a recurrence of laryngeal (n = 3), hypopharyngeal (n = 3) or oropharyngeal (n = 4) cancer after (chemo)radiation with curative intent. Fleiss' and Cohen's Kappa were used to determine interobserver agreement and intraobserver agreement, respectively. RESULTS: Interobserver agreement was κ = 0.55. Intraobserver agreement was κ = 0.80. Prior experience within the field of radiology and with DW-MRI had no significant influence on the scoring. CONCLUSION: For the assessment of HNSCC recurrence after (chemo)radiation by DW-MRI, moderate interobserver agreement and substantial intraobserver agreement was found.

Pulsatile Tinnitus: Differential Diagnosis and Radiological Work-Up.

PURPOSE OF REVIEW: Identification of the underlying cause of pulsatile tinnitus is important for treatment decision making and for prognosis estimation. For this, an adequate diagnostic imaging strategy is crucial. RECENT FINDINGS: Both CT and MRI can be useful, and in general, these modalities provide complementary diagnostic information. The scanning protocol can be optimized based on the estimated a priori chance for finding specific pathology, or the need to rule out more rare but clinical significant disease. In recent years, dynamic CTA, also referred to as 4D-CTA, has become available as a new technique that enables non-invasive evaluation of hemodynamics for the detection, classification, and follow-up of vascular malformations. SUMMARY: The value of different diagnostic imaging modalities in the work-up of pulsatile tinnitus is discussed in relation to the differential diagnosis. Furthermore, imaging findings of different diseases are presented, both for CT and MRI.

Evaluation of tongue squamous cell carcinoma resection margins using ex-vivo MR.

PURPOSE: Purpose of this feasibility study was (1) to evaluate whether application of ex-vivo 7T MR of the resected tongue specimen containing squamous cell carcinoma may provide information on the resection margin status and (2) to evaluate the research and developmental issues that have to be solved for this technique to have the beneficial impact on clinical outcome that we expect: better oncologic and functional outcomes, better quality of life, and lower costs. METHODS: We performed a non-blinded validation of ex-vivo 7T MR to detect the tongue squamous cell carcinoma and resection margin in 10 fresh tongue specimens using histopathology as gold standard. RESULTS: In six of seven specimens with a histopathologically determined invasion depth of the tumor of [Formula: see text] mm, the tumor could be recognized on MR, with a resection margin within a 2 mm range as compared to histopathology. In three specimens with an invasion depth of [Formula: see text] mm, the tumor was not visible on MR. Technical limitations mainly included scan time, image resolution, and the fact that we used a less available small-bore 7T MR machine. CONCLUSION: Ex-vivo 7T probably will have a low negative predictive value but a high positive predictive value, meaning that in tumors thicker than a few millimeters we expect to be able to predict whether the resection margin is too small. A randomized controlled trial needs to be performed to show our hypothesis: better oncologic and functional outcomes, better quality of life, and lower costs.

Resting-state subcortical functional connectivity in HIV-infected patients on long-term cART.

Despite long-term successful treatment with cART, impairments in cognitive functioning are still being reported in HIV-infected patients. Since changes in cognitive function may be preceded by subtle changes in brain function, neuroimaging techniques, such as resting-state functional magnetic resonance imaging (rs-fMRI) have become useful tools in assessing HIV-associated abnormalities in the brain. The purpose of the current study was to examine the extent to which HIV infection in virologically suppressed patients is associated with disruptions in subcortical regions of the brain in comparison to a matched HIV-negative control group. The sample consisted of 72 patients and 39 controls included between January 2012 and January 2014. Resting state functional connectivity was determined between fourteen regions-of-interest (ROI): the left and right nucleus accumbens, amygdala, caudate nucleus, hippocampus, putamen, pallidum and thalamus. A Bayesian method was used to estimate resting-state functional connectivity, quantified in terms of partial correlations. Both groups showed the strongest partial correlations between the left and right caudate nucleus and the left and right thalamus. However, no differences between the HIV patients and controls were found between the posterior expected network densities (control network density = 0.26, SD = 0.05, patient network density = 0.26, SD = 0.04, p = 0.58). The results of the current study show that HIV does not affect subcortical connectivity in virologically controlled patients who are otherwise healthy.

Nigrosome-1 on Susceptibility Weighted Imaging to Differentiate Parkinson's Disease From Atypical Parkinsonism: An In Vivo and Ex Vivo Pilot Study.

BACKGROUND: Previous case-control studies have suggested that the absence of a swallow-tail appearance in the substantia nigra on high-resolution SWI, representing nigrosome-1, has high accuracy to identify Parkinson's disease (PD). The first goal of our study was to evaluate nigrosome-1 ex vivo using optimized high-resolution susceptibility sensitive MRI. Our second goal was to evaluate its diagnostic value in vivo using a clinical 3T SWI sequence to differentiate between PD and atypical parkinsonism (AP) in a cohort of patients with early-stage parkinsonism. MATERIAL/METHODS: Case-control pilot study to evaluate nigrosome-1 ex vivo (2 PD, 2 controls), using high-resolution susceptibility sensitive sequences at 11.7 T MRI. Next, evaluation of nigrosome-1 in vivo using a clinical 3 T SWI sequence in a prospective cohort of 60 patients with early-stage parkinsonism (39 PD, 21 AP). Moreover, 12 control subjects were scanned. The bilateral substantia nigra was evaluated by two neuroradiologists for the presence, absence or indecisive presence of nigrosome-1. The discriminative power was evaluated by Receiver-Operating Characteristic. RESULTS: We identified nigrosome-1 in ex vivo control subjects. Nigrosome-1 was not identified in the ex vivo PD cases. In our prospective clinical cohort study, the AUC for the swallow-tail sign to discriminate between PD and AP was 0.56 (0.41-0.71) for reader 1 and 0.68 (0.55-0.82) for reader 2. CONCLUSIONS: The diagnostic accuracy of the swallow-tail sign was marginal to discriminate between PD and AP using our clinical 3 T SWI sequence.

An international comparison of the management of the neck in early oral squamous cell carcinoma in the Netherlands, UK, and USA.

BACKGROUND: Early oral cavity squamous cell carcinoma (OCSCC) management appears to vary both within and between countries. Variation in practice can be an indicator of absence of evidence-based management and may negatively influence survival and morbidity. The exact variation and the relationship to differences in guidelines are unknown. This study aimed to report on these variations in the Netherlands, UK, and USA, and to evaluate them. METHODS: Information regarding the variation in OCSCC management strategies was obtained from a questionnaire sent to representatives of head and neck cancer centers in the Netherlands, UK, and USA. Within-country and between-country variations were also assessed in light of the different guidelines. RESULTS: In total, representatives of 45 centers completed the questionnaire; 10 from the Netherlands, 26 from the UK and 9 from the USA. Our results demonstrate a distinct variation in the diagnoses, treatment and follow-up of OCSCC, both within and between countries. Only a small amount of variation between countries could be linked to differences in guidelines. CONCLUSIONS: There is high variation in the management of the neck in OCSCC. There seem to be a need for direct evidence about optimal management decisions to establish more evidence-based management and uniform practice.

Cognitive functioning, wellbeing and brain correlates in HIV-1 infected patients on long-term combination antiretroviral therapy.

OBJECTIVE: The objective of the current study is to integrate results from extensive neuropsychological assessment, subjective wellbeing reports and structural neuroimaging findings in successfully treated HIV-infected patients in comparison with a HIV-negative control group. DESIGN: A cross-sectional study. METHODS: Neuropsychological functioning and self-reported wellbeing were assessed in a group of 102 virologically suppressed HIV-infected patients on combination antiretroviral therapy (cART) and 56 controls. Both groups underwent magnetic resonance (MR) examinations and grey matter, white matter and subcortical volumes were determined. Brain parenchymal fraction (BPF) was calculated as an estimated measure of global brain atrophy. RESULTS: HIV-infected patients showed worse information processing speed (P = 0.01) and motor function (P = 0.03) than controls. Also, higher levels of anxiety and depressive symptoms, somatic and cognitive complaints, sleep problems and health distress were found, as well as lower levels of general health perceptions, social functioning and energy (P < 0.05). No differences in wellbeing reports were found between patients on regimens containing either efavirenz or nevirapine and patients on cART without these drugs (P > 0.05). Patients had a smaller BPF (P = 0.04) and thalamus (P = 0.05) than controls. A lower BPF was related to worse motor function and information processing speed in the patients. A smaller thalamus volume was related to lower motor function in the patient group and lower speed of information processing in the controls. CONCLUSION: No profound deficits were found in the current study. The present results demonstrate that HIV has a minor impact on brain, cognition and wellbeing among HIV-infected patients who are otherwise healthy and maintained on a good control of cART.

Magnetic resonance imaging of the carotid artery in long-term head and neck cancer survivors treated with radiotherapy.

BACKGROUND: In head and neck cancer (HNC) patients, long-term treatment-related complications include radiotherapy (RT)-induced carotid vasculopathy and stroke. The current study investigated the magnetic resonance imaging (MRI) characteristics of the carotid wall in long-term HNC survivors treated with RT. METHODS: MRI of the carotid arteries was performed within a prospective cohort of 42 HNC patients on average 7 years after RT. Two independent radiologists assessed maximal vessel wall thickness of common and internal carotid arteries. In case of wall thickening (≥ 2 mm) the MRI signals as well as length of the thickened segment were assessed. RESULTS: Mean (SD) age of the 42 patients at baseline was 53 (13) years and mean (SD) follow-up time after RT was 6.8 (1.3) years. In total 62% were men and 60% had one or more cerebrovascular risk factors. Mean (SD) dose of RT on the common carotid arteries and internal carotid arteries was 57 Gy (11) and 61 Gy (10), respectively. Wall thickening was observed in 58% of irradiated versus 27% of non-irradiated common carotid arteries and 24% of irradiated versus 6% of non-irradiated internal carotid arteries (p < 0.05). Mean (SD) thickness of the irradiated and non-irradiated common carotid arteries was 2.5 (0.9) and 2 (0.7) mm (p = 0.02). Mean thickness of the irradiated and non-irradiated internal carotid arteries was 1.8 (0.8) and 1.5 mm (0.3) (n.s.). Mean length of the thickened vessel wall was 48 mm versus 36 mm in the irradiated versus non-irradiated common carotid arteries (p = 0.03) and 20 mm versus 15 mm in the irradiated versus non-irradiated internal carotid arteries (n.s.). No significant differences were observed for signal intensities of the vessel walls. CONCLUSIONS: Our study showed significantly more vessel wall thickening in irradiated versus non-irradiated carotid arteries years after RT for HNC, while no differences in signal intensities were observed.

Cognitive function, depression, fatigue and quality of life among long-term survivors of head and neck cancer.

BACKGROUND: Long-term cancer treatment complications become more prevalent as survival improves. Little is known about the psychological complications in long-term survivors of head and neck cancer (HNC). We investigated cognitive functioning and its relation with depression, fatigue, cognitive complaints, and brain lesions on MRI. METHODS: This study is part of a multicentre, prospective cohort study of 65 patients treated for HNC. A comprehensive neuropsychological assessment was combined with validated questionnaires on subjective memory complaints, depression, and fatigue after a median of 7 years follow-up. Results were compared with age- and education-adjusted normative data. Further, we evaluated cerebral white matter hyperintensities (WMH), brain volume, and infarctions on MRI. RESULTS: HNC patients had worse cognitive performance in two of the five assessed cognitive domains: episodic memory (z = -0.48, P = .003) and speed of information processing (z = -0.47, P < 0.001). Patients with fatigue performed worse than patients without fatigue on verbal fluency (mean difference in z-score 0.52, P = .02) and speed of information processing (0.49, P = .04). Patients with subjective memory complaints had a worse episodic memory performance (mean difference in z-score -0.96; P = .02). Patients with cerebral infarction(s) on MRI performed worse on fluency (mean difference in z-score 0.74, P = .005). A lower cognitive performance was not associated with depression, WMH or brain volume. CONCLUSION: Long-term HNC survivors showed worse cognitive functioning 7 years after treatment. Cognitive function was associated with subjective complaints and fatigue, but not with depressive symptoms. Cerebral infarctions on MRI were correlated with cognitive function, whereas WMH, and brain volume were not.

[Burn injuries during MR scanning: a case report]. / Brandwonden tijdens een MRI-scan.

In this paper we report one case of skin burns in MRI caused by induced electrical currents. Two second degree skin burns occurred during imaging, while operating within all current safety guidelines. The currents are induced by the magnetic-gradient field, as well as the radiofrequency pulses. A closed conducting loop can occur while there is skin-to-skin contact, or for example when the patient is wearing ECG leads, monitoring sensors or cables. When a loop originates within the patient for a longer time, the current can resonate and dissipate high local energy through a rise in temperature. While rare, clinicians need to be aware of this possible event. By avoiding focal skin-to-skin contact of the extremities in this case, the adverse event could have been avoided.