Use Of Magnetic Resonance Imaging Research Articles

Development of an Online Curriculum for Surgeons on the Use of Pelvic Magnetic Resonance Imaging in Rectal Cancer and Results of a Pilot Study

High-resolution pelvic magnetic resonance imaging (MRI) is a critical tool in the management of patients with rectal cancer. An on-line curriculum was developed for surgical trainees on the interpretation of pelvic MRI in rectal cancer for clinical staging and surgical planning. The online curriculum was developed using the six-step approach to curriculum development for medical education. The curriculum incorporated case-based learning, annotated videos, and narrated presentations on key aspects of pelvic MRI in rectal cancer. A pilot study was conducted to assess curriculum effectiveness among Complex General Surgical Oncology (CGSO) fellows using pre- and post-intervention assessments. Of 15 eligible fellows, nine completed the pilot study (60%). The fellows' median confidence score after completing the online curriculum (40, IQR: 33-46) was significantly higher than their baseline median confidence score (23, IQR: 14-30), P=0.0039. The total practical assessment score significantly increased from a pre-median score of 9 (IQR: 8-11) to a post-median score of 14 (IQR: 13-14), P=0.0078. A subgroup analysis revealed a significant change in the knowledge assessment with a median score of 7 compared to a baseline median score of 4, Z=2.64, P=0.0078. However, the skills assessment showed no significant change. The case-based online curriculum had a positive impact on CGSO fellows' knowledge and confidence in the utilization of pelvic MRI for patients with rectal cancer. This unique on-line curriculum demonstrates a mechanism to enhance shared educational collaboration across CGSO fellowships and other surgical training programs.

TP8.1.12 Diagnostic Utility of MRI in the Evaluation of Potential Malignancy in Patients Presented with Nipple Discharge

Abstract Aims Nipple discharge is a presentation commonly seen at breast clinics. It is conventionally evaluated with physical examination and sonography( or mammography). The aim of this study is to investigate the diagnostic value of magnetic resonance imaging (MRI) as an additional imaging tool in the evaluation of potential malignancy in patients presented with nipple discharge. Methods A retrospective evaluation of 85 patients with nipple discharge who underwent breast ultrasound (USS) and MRI between 04/06/2008 and 25/10/2019 was conducted. Clinical notes, radiographic reports and biopsy results were reviewed. Sensitivity, specificity, positive predictive value and negative predictive value of USS and MRI were calculated. Results Out of the 85 patients (all female; mean age 45.33 +/- 12.93 years old) with nipple discharge, 11 were found to have biopsy-proven malignancy (invasive ductal carcinoma/ ductal carcinoma in situ; 12.94% risk). USS failed to identify seven malignancies (27.27% sensitivity) while MRI missed three malignancies (72.72% sensitivity). USS falsely identified four malignancies from 74 patients with no malignancy (94.59% specificity) while MRI only falsely identified one case (98.65% specificity). For patients with negative USS results (U1/U2/U3) or negative MRI results (BI-RADS category 1,2 or 3), the negative predictive values of USS is 89.74% while that of MRI is 96.05%. The positive predictive values of USS and MRI are 42.86% and 88.88% respectively. Conclusion Compared to USS, MRI has a higher sensitivity, specificity, positive predictive value and predictive value. It will be a valuable addition to the standard nipple discharge evaluation workup to help rule out malignancy.

Assessment of Lung Structure and Regional Function Using 0.55 T MRI in Patients With Lymphangioleiomyomatosis.

Contemporary lower-field magnetic resonance imaging (MRI) may offer advantages for lung imaging by virtue of the improved field homogeneity. The aim of this study was to evaluate the utility of lower-field MRI for combined morphologic imaging and regional lung function assessment. We evaluate low-field MRI in patients with lymphangioleiomyomatosis (LAM), a rare lung disease associated with parenchymal cysts and respiratory failure. We performed lung imaging on a prototype low-field (0.55 T) MRI system in 65 patients with LAM. T2-weighted imaging was used for assessment of lung morphology and to derive cyst scores, the percent of lung parenchyma occupied by cysts. Regional lung function was assessed using oxygen-enhanced MRI with breath-held ultrashort echo time imaging and inhaled 100% oxygen as a T1-shortening MR contrast agent. Measurements of percent signal enhancement from oxygen inhalation and percentage of lung with low oxygen enhancement, indicating functional deficits, were correlated with global pulmonary function test measurements taken within 2 days. We were able to image cystic abnormalities using T2-weighted MRI in this patient population and calculate cyst score with strong correlation to computed tomography measurements (R = 0.86, P < 0.0001). Oxygen-enhancement maps demonstrated regional deficits in lung function of patients with LAM. Heterogeneity of oxygen enhancement between cysts was observed within individual patients. The percent low-enhancement regions showed modest, but significant, correlation with FEV1 (R = -0.37, P = 0.007), FEV1/FVC (R = -0.33, P = 0.02), and cyst score (R = 0.40, P = 0.02). The measured arterial blood ΔT1 between normoxia and hyperoxia, used as a surrogate for dissolved oxygen in blood, correlated with DLCO (R = -0.28, P = 0.03). Using high-performance 0.55 T MRI, we were able to perform simultaneous imaging of pulmonary structure and regional function in patients with LAM.

The Effect of the Eastern Association for the Surgery of Trauma Guideline on Spinal Magnetic Resonance Imaging Use in Obtunded Adult Blunt Trauma Patients Over Time

Evidence-based guidelines suggest computed tomography without magnetic resonance imaging (MRI) is sufficient to rule out clinically significant cervical spine injury in obtunded adult blunt trauma patients. This study evaluated MRI utilization over time to investigate the impact of the 2015 Eastern Association for the Surgery of Trauma guidelines suggesting cervical collar clearance with computed tomography alone in this population.We hypothesized that MRI utilization would decrease following the guidelines. We performed a retrospective cross-sectional study of the National Trauma Data Bank from 2007 to 2018 using multivariable logistic regression of the likelihood of spinal MRI utilization. Blunt trauma patients 18 y and older with a Glasgow Coma Scale (GCS) of 8 or less, Abbreviated Injury Score head of 4 or greater, intubated for at least 72 h were included. The sample consisted of 76,450 patients from 567 trauma centers. Controlling for age, gender, race/ethnicity, insurance status, injury mechanism, Injury Severity Score, GCS, GCS motor, hospital teaching status and trauma center level, patients seen after 2015 had a higher odds ratio (OR) of undergoing spinal MRI relative to those seen before 2015 (OR 1.77, 95% CI 1.49-2.09; P < 0.001). Each year was associated with a significantly increased OR of undergoing spinal MRI compared to the year prior (OR 1.10, 95% CI 1.05-1.15; P < 0.001). Spinal MRI use has been increasing in obtunded adult blunt trauma patients including after the release of the Eastern Association for the Surgery of Trauma guidelines in 2015. Future work should identify whether this is driven by improper MRI utilization and, if so, strategies to promote guideline adherence.

Magnetic Resonance Arthrography of the Wrist: The Impact on Operative Management of Wrist Injuries.

Background There is no consensus on the utility of arthrography in the evaluation of wrist injuries. This study evaluates ordering trends of different types of magnetic resonance imaging (MRI) of the wrist and compares rates of surgery following these imaging modalities. Methods A national claims-based database was used to identify patients who underwent MRI within 90 days of a first-instance diagnosis of wrist injury from 2010 to 2018. The utilization of MRI without intravenous (IV) contrast, MRI with IV contrast, and MRI with arthrogram was investigated. The instances of operative procedures of the wrist within 1 year of MRI study were recorded. Patient demographics, comorbidities, type of operative procedure, and ordering physician specialty were obtained. Logistic regression analysis was used to evaluate the utilization of MRI and subsequent 1-year operative intervention rates as well as association of patient-related factors. Results Magnetic resonance arthrography use was associated with higher rates of subsequent operative treatment. Surgeons were more likely to order an arthrogram at the time of MRI. Younger patients were more likely to undergo MRI-based advanced imaging. Conclusion Surgeons may perceive MRA of the wrist to play an important role in operative decision-making following wrist injury. Level of Evidence This is a Level III, retrospective cohort study.

Use of Magnetic Resonance Imaging in Acute Traumatic Brain Injury Patients is Associated with Lower Inpatient Mortality.

Objectives:While magnetic resonance imaging (MRI) has higher sensitivity than computed tomography for certain types of traumatic brain injury (TBI), it remains unknown whether the increased detection of intracranial injuries leads to improved clinical outcomes in acute TBI patients, especially given the resource requirements involved in performing MRI. We leveraged a large national patient database to examine associations between brain MRI utilization and inpatient clinical outcomes in hospitalized TBI patients.Material and Methods:The National Inpatient Sample database was queried to find 3,075 and 340,090 hospitalized TBI patients with and without brain MRI, respectively, between 2012 and 2014 in the United States. Multivariate regression analysis was performed to independently evaluate the association between brain MRI utilization and inpatient mortality rate, complications, and resource requirements.Results:The MRI group had a lower unadjusted mortality rate of 0.75% compared to 2.54% in the non-MRI group. On multivariate regression analysis, inpatient brain MRI was independently associated with lower mortality (adjusted OR 0.32, 95% CI 0.12–0.86), as well as higher rates of intracranial hemorrhage (adjusted OR 2.20, 95% CI 1.27–3.81) and non-home discharge (adjusted OR 1.33, 95% CI 1.07–1.67). Brain MRI was independently associated with 3.4 days (P < 0.001) and $8,934 (P < 0.001) increase in the total length and cost of hospital stay, respectively.Conclusion:We present the first evidence that inpatient brain MRI in TBI patients is associated with lower inpatient mortality, but with increased hospital resource utilization and likelihood of non-home discharge.

S2484 Endoscopic Ultrasound With Fine Needle Aspiration for Diagnosis of Pancreatic Tumors in Patients With Benign Magnetic Resonance Imaging: Single Center Case Series

Introduction: Pancreatic cancer is the fourth leading cause of cancer-related death in the United States. Computed tomography (CT) scan and Magnetic resonance imaging (MRI) are used for early detection of small pancreatic lesions and cancer risk stratification. Endoscopic ultrasonography (EUS) with FNA (Fine Needle Aspiration) provides accurate diagnosis of pancreatic tumors. This case series introduces four cases of pancreatic tumors diagnosed using EUS/FNA that have been missed on MRI studies Case Description/Methods: Case 1 64-year-old male was referred for evaluation of pancreatic duct dilation on MRI with no detected mass. EUS revealed 15mm x 15mm mass of pancreas. FNA was performed and pathology was consistent with adenocarcinoma Case 2 55-year-old female was referred for evaluation of pancreatic cystic lesion found on MRI with no worrisome features. EUS revealed 15mm x 15mm pancreatic lesion. FNA was performed and pathology was consistent with pancreatic neuroendocrine tumor. Case 3 82-year-old female was referred for evaluation of pancreatic duct dilation on MRI with no discrete mass identified. EUS revealed 26mm x 27mm pancreatic lesion. FNA was performed and pathology was consistent with invasive adenocarcinoma. Case 4 62-year-old male was referred for evaluation of pancreatic lesion on MRI abdomen with features consistent with lipoma. EUS revealed 15mm x 13mm pancreatic lesion. FNA was performed and pathology was consistent with adenocarcinoma. Discussion: The diagnosis of pancreatic neoplasms relies heavily on identification of lesions on CT and MRI. While the sensitivity of MRI is similar to that of CT, the former is preferred in patients with high pre-test probability of pancreatic neoplasms. Sensitivity of EUS has been shown to be significantly higher in detecting pancreatic tumors when compared to CT, However, studies evaluating EUS to MRI are scarce. This case series presents four patients in whom pancreatic tumors were missed on MRI. Two patients had no radiologic evidence of a tumor, while the other two demonstrated lesions with no malignant features. EUS has the added benefit of tumor sampling and higher sensitivity in detecting pancreatic lesions. This case series highlights the potential limitations in the use of MR imaging in diagnosis of pancreatic cancers. Some evidence suggests that EUS is more sensitive than MRI and CT in detecting pancreatic lesions. However, the cost effectiveness and risks associated with routine EUS in the detection of pancreatic lesions has not been evaluated.Figure 1.: (A): Case 3 EUS with arrow pointing at 26mm x 27mm pancreatic lesion (B): Case 4 EUS with arrow pointing at 15mm x 13mm pancreatic lesion.

Feasibility and utility of MRI and dynamic 18F-FDG-PET in an orthotopic organoid-based patient-derived mouse model of endometrial cancer

BackgroundPelvic magnetic resonance imaging (MRI) and whole-body positron emission tomography-computed tomography (PET-CT) play an important role at primary diagnostic work-up and in detecting recurrent disease in endometrial cancer (EC) patients, however the preclinical use of these imaging methods is currently limited. We demonstrate the feasibility and utility of MRI and dynamic 18F-fluorodeoxyglucose (FDG)-PET imaging for monitoring tumor progression and assessing chemotherapy response in an orthotopic organoid-based patient-derived xenograft (O-PDX) mouse model of EC.Methods18 O-PDX mice (grade 3 endometrioid EC, stage IIIC1), selectively underwent weekly T2-weighted MRI (total scans = 32), diffusion-weighted MRI (DWI) (total scans = 9) and dynamic 18F-FDG-PET (total scans = 26) during tumor progression. MRI tumor volumes (vMRI), tumor apparent diffusion coefficient values (ADCmean) and metabolic tumor parameters from 18F-FDG-PET including maximum and mean standard uptake values (SUVmax/SUVmean), metabolic tumor volume (MTV), total lesion glycolysis (TLG) and metabolic rate of 18F-FDG (MRFDG) were calculated. Further, nine mice were included in a chemotherapy treatment study (treatment; n = 5, controls; n = 4) and tumor ADCmean-values were compared to changes in vMRI and cellular density from histology at endpoint. A Mann–Whitney test was used to evaluate differences between groups.ResultsTumors with large tumor volumes (vMRI) had higher metabolic activity (MTV and TLG) in a clear linear relationship (r2 = 0.92 and 0.89, respectively). Non-invasive calculation of MRFDG from dynamic 18F-FDG-PET (mean MRFDG = 0.39 μmol/min) was feasible using an image-derived input function. Treated mice had higher tumor ADCmean (p = 0.03), lower vMRI (p = 0.03) and tumor cellular density (p = 0.02) than non-treated mice, all indicating treatment response.ConclusionPreclinical imaging mirroring clinical imaging methods in EC is highly feasible for monitoring tumor progression and treatment response in the present orthotopic organoid mouse model.

The Anatomical Relationships in the Space of Retzius for Penile Implants: An MRI Analysis

The 3-piece inflatable penile prosthesis includes an easy-to-use pump and fluid filled reservoir which is placed in either the space of Retzius (SOR) or in an alternative ectopic location. Reservoir placement in the SOR is a blind procedure despite the SOR being surrounded by many critical structures. To date only a handful of cadaveric studies have described the relevant anatomy. To use magnetic resonance imaging (MRI) as an in-vivo model to study relevant retropubic anatomy critical for SOR reservoir placement. The study population included men with elevated prostate specific antigen or biopsy proven prostate cancer who (i) underwent pelvic MRI, (ii) without prior pelvic or inguinal surgery, and (iii) without pelvic radiation therapy. All MRIs were completed with a 3-Tesla scanner and endorectal coil. Both T1 and T2 weighted images were captured in both axial and sagittal planes. All images were reviewed by 2 independent reviewers under the supervision of a dedicated body MRI radiologist. Bladder volume was calculated using an ellipsoid formula. Relevant measurements included (i) the distance between the external inguinal ring (EIR) at the level of the pubic tubercle to the external iliac vein (EIV), (ii) the distance from the EIR at the pubic tubercle to the bladder (accounting for bladder volume) and (iii) the distance from the midline pubic symphysis to the bladder (accounting for bladder volume). Pearson correlation was used to determine correlated measurements. A total of 24 patients were included. Median participant age was 63 years (interquartile range, 59-66). The mean EIR-EIV distance was 3.0 ± 0.4 cm, the mean EIR-bladder distance was 1.8 ± 1.0 cm and the mean distance from the superior pubic symphysis to bladder was 0.9 ± 0.3 cm. There was a weak correlation between bladder volume and distance between the EIR and bladder (r = -0.30, P = .16). The use of MRI as an in-vivo model is a high-fidelity tool to study real time unaltered anatomy and allows for surgical preparation, diagnosis of anatomic variants and acts as a valuable teaching tool. This is the first in-vivo model to report relevant retropubic anatomy in penile implant surgery. Our study is limited by sample size and inclusion of participants with no history of prior pelvic intervention. We demonstrate the utility of MRI as an in-vivo model, as opposed to cadaveric models, for the understanding of relevant retropubic anatomy for implant surgeons.

Guidelines on postoperative magnetic resonance imaging in patients operated for cryptoglandular anal fistula: Experience from 2404 scans.

Magnetic resonance imaging (MRI) is considered the gold standard for the evaluation of anal fistulas. There is sufficient literature available outlining the interpretation of fistula MRI before performing surgery. However, the interpretation of MRI becomes quite challenging in the postoperative period after the surgery of fistula has been undertaken. Incidentally, there are scarce data and no set guidelines regarding analysis of fistula MRI in the postoperative period. In this article, we discuss the challenges faced while interpreting the postoperative MRI, the timing of the postoperative MRI, the utility of MRI in the postoperative period for the management of anal fistulas, the importance of the active involvement and experience of the treating clinician in interpreting MRI scans, and the latest advancements in the field.

Magnetic resonance imaging cervical spine in trauma: A retrospective single-centre audit of patient outcomes.

Magnetic resonance imaging (MRI) is often used in practice to investigate for cord or discoligamentous injury following blunt trauma and a normal computed tomography (CT). This study investigates the MRI findings and surgical outcomes of patients in this cohort. Retrospective analysis of patients following trauma with suspected cervical spine injury from 2016 to 2019. Inclusion criteria included patients receiving a normal CT of the cervical spine and subsequent MRI due to cervical spine injury symptomatology (persistent tenderness and/or neurology). Inclusion criteria included: age ≥16 years, alert and <72 h from CT to MRI. Mann-Whitney and χ2 statistical analysis techniques were employed. Two hundred and twenty-eight patients with persistent midline tenderness and/or persistent neurology following blunt trauma and negative CT report were included. One hundred and eighty-one patients received an MRI for persistent tenderness of which 35 revealed abnormal MRI findings. Twenty-one cases required no treatment, 14 cases were treated with a rigid collar with no patients requiring operative management. Forty-seven patients received an MRI for neurological symptoms following blunt trauma and negative CT, with 11 abnormal MRI findings. Management included no treatment (three cases), application of rigid collar (six cases) and operative management (two cases). No alert neurologically intact patient with 'persistent tenderness only' received operative management following a normal CT examination. While MRI is sensitive for detecting soft tissue injuries, the prevalence for detecting clinically significant cervical spine injury in blunt trauma patients in the absence of neurology is low. The utility of MRI in this cohort is questionable considering prolonged spinal immobilisation is not without harm.

Feasibility of Abdominal Magnetic Resonance Imaging in Patients With Residual Concentrated Enteric Contrast After Fluoroscopic Abdominal Examination.

This study aimed to evaluate the image quality, image artifacts, radiologist confidence, and ability to provide definitive diagnosis for all patients with magnetic resonance imaging (MRI) performed after an abdominal fluoroscopic examination and to determine the utility of MRI in this setting. Thirty-one MRI examinations performed a median of 2 days after fluoroscopic bowel evaluation (barium, n = 13; iodine, n = 18), 20 within 3 days of MRI, were retrospectively reviewed. The image quality, artifact emanating from bowel, inhomogeneity artifact, radiologist confidence, ability to render a definitive diagnosis, and identification of emergent or important findings for all MRI examinations were assessed. These same features were evaluated on 5 computed tomographies performed after fluoroscopy (before the MRI) in the same cohort. All 31 MRI examinations performed after fluoroscopic studies with concentrated barium or iodine solutions were diagnostic for answering the clinical question according to radiologist and report review, regardless of magnet strength and type of fluoroscopic contrast ingested. Magnetic resonance imaging after fluoroscopy had excellent overall image quality (mean score, 4.74/5), minimal to no artifact emanating from bowel (mean, 4.63/5), minimal inhomogeneity artifact (mean, 4.38/5), and excellent diagnostic confidence (mean, 4.98/5). No additional imaging was necessary for diagnosis after MRI. Computed tomography after fluoroscopy had lower overall image quality, more image artifacts, and lower diagnostic confidence (P < 0.05). Magnetic resonance imaging is a useful tool for evaluating patients with retained concentrated enteric contrast from recent fluoroscopic examinations. In the absence of contraindication, MRI should be considered in the evaluation of urgent clinical problems in patients who recently underwent a fluoroscopic bowel evaluation.

A Clinical Prediction Tool for MRI in Emergency Department Patients with Spinal Infection.

IntroductionPatients with pyogenic spinal Infection (PSI) are often not diagnosed at their initial presentation, and diagnostic delay is associated with increased morbidity and medical-legal risk. We derived a decision tool to estimate the risk of spinal infection and inform magnetic resonance imaging (MRI) decisions.MethodsWe conducted a two-part prospective observational cohort study that collected variables from spine pain patients over a six-year derivation phase. We fit a multivariable regression model with logistic coefficients rounded to the nearest integer and used them for variable weighting in the final risk score. This score, SIRCH (spine infection risk calculation heuristic), uses four clinical variables to predict PSI. We calculated the statistical performance, MRI utilization, and model fit in the derivation phase. In the second phase we used the same protocol but enrolled only confirmed cases of spinal infection to assess the sensitivity of our prediction tool.ResultsIn the derivation phase, we evaluated 134 non-PSI and 40 PSI patients; median age in years was 55.5 (interquartile range [IQR] 38–70 and 51.5 (42–59), respectively. We identified four predictors for our risk score: historical risk factors; fever; progressive neurological deficit; and C-reactive protein (CRP) ≥ 50 milligrams per liter (mg/L). At a threshold SIRCH score of ≥ 3, the predictive model’s sensitivity, specificity, and positive predictive value were, respectively, as follows: 100% (95% confidence interval [CI], 100–100%); 56% (95% CI, 48–64%), and 40% (95% CI, 36–46%). The area under the receiver operator curve was 0.877 (95% CI, 0.829–0.925). The SIRCH score at a threshold of ≥ 3 would prompt significantly fewer MRIs compared to using an elevated CRP (only 99/174 MRIs compared to 144/174 MRIs, P <0.001). In the second phase (49 patient disease-only cohort), the sensitivities of the SIRCH score and CRP use (laboratory standard cut-off 3.5 mg/L) were 92% (95% CI, 84–98%), and 98% (95% CI, 94–100%), respectively.ConclusionThe SIRCH score provides a sensitive estimate of spinal infection risk and prompts fewer MRIs than elevated CRP (cut-off 3.5 mg/L) or clinician suspicion.

Diffuse Axonal Injury Grade on Early MRI is Associated with Worse Outcome in Children with Moderate-Severe Traumatic Brain Injury.

BackgroundTraumatic brain injury (TBI) is the leading cause of death and disability in children, but effective tools for predicting outcome remain elusive. Although many pediatric patients receive early magnetic resonance imaging (MRI), data on its utility in prognostication are lacking. Diffuse axonal injury (DAI) is a hallmark of TBI detected on early MRI and was shown previously to improve prognostication in adult patients with TBI. In this exploratory study, we investigated whether DAI grade correlates with functional outcome and improves prognostic accuracy when combined with core clinical variables and computed tomography (CT) biomarkers in pediatric patients with moderate-severe TBI (msTBI).MethodsPediatric patients (≤ 19 years) who were admitted to two regional level one trauma centers with a diagnosis of msTBI (Glasgow Coma Scale [GCS] score < 13) between 2011 and 2019 were identified through retrospective chart review. Patients who underwent brain MRI within 30 days of injury and had documented clinical follow-up after discharge were included. Age, pupil reactivity, and initial motor GCS score were collected as part of the International Mission for Prognosis and Analysis of Clinical Trials in TBI (IMPACT) model. Imaging was reviewed to calculate the Rotterdam score (CT) and DAI grade (MRI) and to evaluate for presence of hypoxic-ischemic injury (MRI). The primary outcome measure was the Pediatric Cerebral Performance Category Scale (PCPCS) score at 6 months after TBI, with favorable outcome defined as PCPCS scores 1–3 and unfavorable outcome defined as PCPCS scores 4–6. The secondary outcome measure was discharge disposition to home versus to an inpatient rehabilitation facility.ResultOf 55 patients included in the study, 45 (82%) had severe TBI. The most common mechanism of injury was motor vehicle collision (71%). Initial head CT scans showed acute hemorrhage in 84% of patients. MRI was acquired a median of 5 days after injury, and hemorrhagic DAI lesions were detected in 87% of patients. Each 1-point increase in DAI grade increased the odds of unfavorable functional outcome by 2.4-fold. When controlling for core IMPACT clinical variables, neither the DAI grade nor the Rotterdam score was independently correlated with outcome and neither significantly improved outcome prediction over the IMPACT model alone.ConclusionsA higher DAI grade on early MRI is associated with worse 6-month functional outcome and with discharge to inpatient rehabilitation in children with acute msTBI in a univariate analysis but does not independently correlate with outcome when controlling for the GCS score. Addition of the DAI grade to the core IMPACT model does not significantly improve prediction of poor neurological outcome. Further study is needed to elucidate the utility of early MRI in children with msTBI.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12028-021-01336-8.

Multiparametric cardiac magnetic resonance imaging in pediatric and adolescent patients with acute myocarditis

BackgroundThe diagnostic value of cardiac magnetic resonance imaging (MRI) employing the 2018 Lake Louise criteria in pediatric and adolescent patients with acute myocarditis is undefined.ObjectiveTo evaluate the diagnostic value of the Lake Louise criteria in pediatric and adolescent patients with suspected acute myocarditis and to show the utility of cardiac MRI for follow-up in this patient cohort.Materials and methodsForty-three patients (age range: 8–21 years) with suspected acute myocarditis and 13 control patients who underwent cardiac MRI were retrospectively analyzed. T2-weighted and late gadolinium enhancement imaging were performed in all patients. T1 and T2 mapping were available in 26/43 patients (60%). The Lake Louise criteria were assessed. In 27/43 patients (63%), cardiac MRI follow-up was available. Receiver operating characteristic analysis, Pearson’s correlation coefficient and paired Student’s t-test were used for statistical analysis.ResultsIn the total cohort, the Lake Louise criteria achieved a sensitivity of 86% (95% confidence interval [CI]: 72–95%) and a specificity of 100% (95% CI: 79–100%) for the diagnosis of acute myocarditis. In the subgroup of patients with available mapping parameters, the diagnostic performance of the Lake Louise criteria was higher when mapping parameters were implemented into the score (area under the receiver operating characteristic curve: 0.944 vs. 0.870; P=0.033). T2 relaxation times were higher in patients with admission to the intermediate care unit and were associated with the length of intermediate care unit stay (r=0.879, P=0.049). Cardiac MRI markers of active inflammation decreased on follow-up examinations (e.g., T1 relaxation times: 1,032±39 ms vs. 975±33 ms, P<0.001; T2 relaxation times: 58±5 ms vs. 54±5 ms, P=0.003).ConclusionThe Lake Louise criteria have a high diagnostic performance for the diagnosis of acute myocarditis and are a valuable tool for follow-up in pediatric and adolescent patients. The mapping techniques enhance the diagnostic performance of the 2018 Lake Louise criteria.

The clinical utility of inpatient MRI following an abdominopelvic CT.

The purpose of this study was to assess the diagnostic yield of abdomen magnetic resonance imaging (MRI) in the inpatient setting following a computed tomography (CT). All inpatient abdominopelvic MRIs performed on patients for a 1-year period were identified and medical records were retrospectively reviewed for the following information. Only MRIs with a preceding CT were included in the study. A total of 221 MRIs were included. Forty exams were deemed technically inadequate due to motion, while 9 more patients did not tolerate a full examination. The most common indications were focal liver lesion (n = 101), pancreaticobiliary ductal dilatation (n = 39), abnormal liver function tests (n = 26), acute pancreatitis (n = 14), abdominal pain (n = 10), and fever/sepsis (n = 10). 83 MRIs were recommended on CT and 138 were requests from the care team. In 63 cases, MRI offered new information over CT. Thirty-two MRIs recommended by radiologists affected patient management, while only 31 MRIs recommended by the care team affected management. Of these 63 MRIs, 29 cases changed immediate inpatient management, requiring further intervention. In these cases, MRI identified abscesses, choledocholithiasis, or made other diagnoses such as cholecystitis, which were not diagnosed on CT. Patient LOS increased in 24 patients in order to receive an MRI. Average costs of outpatient CTs and MRIs are typically 20% less than inpatient costs. Inpatient abdomen MRIs have limited impact on patient care following a CECT and entail higher cost, utilize more resources, scanner time, and increase patient LOS. Therefore, it should be reserved for select clinical indications.

The clinical significance of magnetic resonance imaging of the hand: an analysis of 318 hand and wrist images referred by hand surgeons

Magnetic resonance imaging (MRI) is a common diagnostic tool in hand surgery. However, there is limited knowledge on the kind of findings that are relevant in treatment planning. We analysed the findings and utility of arm, wrist, metacarpal, and finger MRIs taken in a tertiary hand surgery clinic of 318 consecutive images from 316 patients referred by a hand surgeon or hand surgeon resident. Ganglions (28%), findings on the extensor carpi ulnaris tendon (18%) and on the triangular fibrocartilage (18%) were the most common findings and increased with patient age; the clinical significance of these findings was minimal. The correlation between the clinical scaphoid shift test or the fovea sign test and MRI was also non-significant. Despite findings on MRI, the diagnosis remained unsolved in 76 (24%) cases. However, MRI had a role in reassuring the patient, and in 70% of the cases, further follow-up was unnecessary. This study demonstrates that the indications for wrist and hand MRI must be considered thoroughly and interpretation of the MRI report requires knowledge.

National and regional trends in MRI utilization in the face of the ongoing COVID-19 pandemic

Background and purposeMarked reductions in imaging exams have been documented during the COVID-19 pandemic. The study aimed to examine the effect of the two waves of COVID-19 on magnetic resonance imaging (MRI) utilization at the national and regional level.Materials and methodsA retrospective-archive study was conducted in Israel, comparing March–December 2020 with March–December 2018 and 2019. Data on MRI utilization were obtained from the national MRI registry, while data on confirmed COVID-19 cases, by place of residence, were obtained from the Israeli Ministry of Health open COVID-19 database.ResultsThe number and rate of MRI examinations decreased during the first COVID-19 wave, with the steepest drop in April 2020: 47.5% relative decrease compared to April 2019, and 42.2% compared to 2018. This was followed by a compensatory increase between the waves and a return to almost pre-pandemic levels of use, with just a modest decrease, during the second, more intense COVID wave, compared with the previous year. Existing differences between regions increased during the pandemic. The rate ratio of MRI exams between Tel-Aviv and the Northern periphery increased from 2.89 in April 2019 to 3.94 in April 2020. Jerusalem metropolitan region, with the largest burden of COVID disease, demonstrated only a modest decrease (1%) in MRI utilization during the first 10 months of the pandemic.ConclusionsAt the national level, time trends in reduced MRI utilization followed the first wave of COVID-19, and were accompanied by increased regional disparities. These changes were not explained by differences in the burden of COVID-19 disease but might be explained by unequal distribution of MRI scanners among regions. Reduced utilization was not evident during the second wave, nor at the beginning of the third wave, despite higher COVID-19 case load, demonstrating adaptation to the new normal. Patterns of MRI utilization might help policy-makers and healthcare managers predict the behavior of imaging as well as other sectors, such as elective surgical procedures, during an ongoing pandemic. This forecast might help to manage the lasting effects of the pandemic, including extended waiting times, in the months and years following its remission. In preparation for future national emergencies, timely and detailed data on MRI utilization can serve as a “sensor” for a wide array of diagnostic and interventional medical activities, providing policy-makers with an updated snapshot to guide their response at the regional and national levels.

Problem-solving with MRI in acute abdominopelvic conditions, part 1: gastrointestinal, hepatobiliary, and pancreatic diseases.

The purpose of this article is to review the benefit and added value and advantages of magnetic resonance imaging (MRI) compared with other cross-sectional imaging in patients presenting with abdominopelvic emergencies. During the past decade, there has been increased utilization of MRI in the emergency department with widespread availability of MR scanners, improvement in rapid imaging techniques, and methods to overcome motion-related artifacts. This has benefited patients at higher risk of radiation, particularly children and pregnant women, and patients with contraindications to iodinated contrast including allergy and renal dysfunction. Still the challenges are: on site MR scanner in the emergency department, after-hour services, as well as availability of time slot to rapidly scan emergency patient. MRI has additional advantages over other imaging modalities due to its high contrast resolution, which allows it to better characterize tissue and fluid collections, and may avoid the need for intravenous contrast. Radiologists must be familiar with the role and added value of MRI, spectrum of imaging findings, and problem-oriented modified MR protocols in abdominal and pelvic emergencies. In part 1, we will discuss the utility of MRI in gastrointestinal, hepatobiliary, and pancreatic diseases. In part 2, the authors will focus on the key MR imaging features of female pelvic gynecological diseases, pregnancy related complications, abdominal vascular complications, and renal diseases.

Effects of MR imaging time reduction on substitute CT generation for prostate MRI-only treatment planning.

The introduction of MRI linear accelerators (MR-linacs) and the increased use of MR imaging in radiotherapy, requires improved approaches to MRI-only radiotherapy. MRI provides excellent soft tissue visualisation but does not provide any electron density information required for radiotherapy dose calculation, instead MRI is registered to CT images to enable dose calculations. MRI-only radiotherapy eliminates registration errors and reduces patient discomfort, workload and cost. Electron density requirements may be addressed in different ways, from manually applying bulk density corrections, to more computationally intensive methods to produce substitute CT datasets (sCT), requiring additional sequences, increasing overall imaging time. Reducing MR imaging time would reduce potential artefacts from intrafraction motion and patient discomfort. The aim of this study was to assess the impact of reducing MR imaging time on a hybrid atlas-voxel sCT conversion for prostate MRI-only treatment planning, considering both anatomical and dosimetric parameters. 10 volunteers were scanned on a Siemens Skyra 3T MRI. Sequences included the 3D T2-weighted (T2-w) SPACE sequence used for sCT conversion as previously validated against CT, along with variations to this sequence in repetition time (TR), turbo factor, and combinations of these to reduce the imaging time. All scans were converted to sCT and were compared to the sCT from the original SPACE sequence, evaluating for anatomical changes and dosimetric differences for a standard prostate VMAT plan. Compared to the previously validated T2-w SPACE sequence, scan times were reduced by up to 80%. The external volume and bony anatomy were compared, with all but one sequence meeting a DICE coefficient of 0.9 or better, with the largest variations occurring at the edges of the external body volume. The generated sCT agreed with the gold standard sCT within an isocentre dose of 1% and a gamma pass rate of 99% for a 1%/1mm gamma tolerance for all but one sequence. This study demonstrates that the MR imaging sequence time was able to be reduced by approximately 80% with similar dosimetric results.