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Background: Patient genetic polymorphism is associated with Crohn's clinical behavior; however, its association with magnetic resonance enterography (MRE) imaging appearance is not known.Purpose: To analyze a set of known Crohn's disease (CD)-related single nucleotide polymorphisms for associations with MRE imaging phenotype and frequency of imaging.Study Type: Retrospective.Population: 54 patients (mean age 40 years; 32 females and 22 males) with established CD from 2009 to 2016 who underwent baseline MRE and genetic testing for the presence of 168 single nucleotide polymorphisms (SNPs) potentially associated with inflammatory bowel disease.Field Strength/sequence: 1.5T or 3T clinical scanners, standard MRE clinical pulse sequences, including T2 -weighted single-shot fast spin echo, balanced steady-state free precession, T2 -weighted fast spin echo fat-suppressed, and T1 -weighted fat-suppressed pre- and postcontrast imaging.Assessment: Three readers (all body imaging fellowship-trained radiologists) independently evaluated all imaging for the presence or absence of active disease and penetrating complications. Date of onset and frequency of endoscopies and cross-sectional imaging (CSI) were recorded. Disease behavior and distribution were categorized according to the Vienna and Montreal classifications, respectively.Statistical Tests: Student's t-test and Fisher's exact test were used to assess significance of continuous and categorical variables, respectively. A hidden Markov model statistical knockoff approach was also applied for the analysis of genetic-imaging associations, with corrected P < 0.05 considered significant.Results: MRE demonstrated active bowel inflammation in 42 (78%) patients, strictures in 13 (28%), and fistulae in 13 (28%). The SNP rs1292053 (RBS6KB1) was highly associated with small bowel inflammation and luminal narrowing, with observed frequencies of association 0.66 and 0.39, respectively (P = 0.001). rs6062504 (Decoy receptor 3) was associated with lower age of onset (P = 0.012), higher proportion of early disease onset patients (P = 0.012), and higher average number of CSI/year (P = 0.014).Data Conclusion: This study demonstrated significant associations between CD genotype and MRE phenotype and frequency of cross-sectional imaging.Level Of Evidence: 3 TECHNICAL EFFICACY STAGE: 2. [ABSTRACT FROM AUTHOR]

Purpose: To formulate consensus recommendations for CT angiography technical parameters used to evaluate overt gastrointestinal (GI) bleeding. Methods: An electronic questionnaire consisting of 17 questions was sent to a panel of 16 radiologists with expertise on the imaging of GI bleeding from the Society of Abdominal Radiology GI Bleeding disease-focused panel to obtain consensus agreement on issues related to CTA technical parameters for imaging overt GI bleeding. A multi-round Delphi method of voting was performed to obtain consensus which was defined as ≥ 80% agreement. Results: Consensus agreement was reached in 15/17 (89%) of the questions including the technique for the administration of IV contrast, the number of phases, scan timing, and image reconstruction. Conclusions: A panel of experts on the imaging of GI bleeding from the Society of Abdominal Radiology was able to reach consensus on the majority of technical parameters used for CTA of overt GI bleeding. These recommendations should improve the quality of patient care by adopting these minimal technical requirements for optimal exam performance and lead to less variation in the performance of these exams which will facilitate collecting and comparing published data from different centers. These recommendations will need revisions as additional scientific data become available. [ABSTRACT FROM AUTHOR]

Hepatocyte-specific contrast agents (HSCAs) are a group of intravenous gadolinium-based MRI contrast agents that can be used to characterize hepatobiliary pathology. The mechanism by which these agents are taken up by hepatocytes and partially excreted into the biliary tree improves characterization of hepatic lesions and biliary abnormalities relative to conventional extracellular gadolinium-based contrast agents (GBCAs). This manuscript presents an overview of HSCA use in pediatric patients with the intent to provide radiologists a guide for clinical use. We review available HSCAs and discuss dosing and age specifications for use in children. We also review various hepatic and biliary indications for HSCA use in children, with emphasis on the imaging characteristics distinct to HSCAs, as well as discussion of pitfalls one can encounter when imaging with HSCAs. Given the growing concern regarding gadolinium deposition in soft tissues and brain, we also discuss safety of HSCA use in children. [ABSTRACT FROM AUTHOR]

Purpose: To determine the clinical significance of incidentally discovered renal cysts in pediatric patients and identify imaging predictors of autosomal dominant polycystic kidney disease (ADPKD). Methods: A retrospective search of radiology reports from 2000 to 2016 was performed to identify patients < 18 years old with an imaging exam identifying at least one renal cyst and a ≥ 1-year follow-up renal imaging exam for cyst evaluation and/or diagnosis of ADPKD. Cysts with clear solid mass components were excluded. Results: 84 pediatric patients with renal cysts were identified (mean age, 9.5 years), including 76 patients with incidentally discovered cysts and 8 patients with cysts identified from screening for ADPKD family history. Among the incidentally discovered cyst group, 7.9% were found to have ADPKD compared with 100% of patients with cysts and ADPKD family history. Maximum cyst diameter was significantly increased in patients with ADPKD compared to patients without ADPKD (22.0 mm vs 12.7 mm; P < 0.001, Fisher's Exact test). Multiple cysts or bilateral cysts were imaging features associated with a significantly higher (P < 0.01) incidence of ADPKD, both for the entire study population and the incidentally discovered cyst group. An increase in cyst size on the follow-up study was associated with higher incidence of ADPKD (P < 0.05). No malignancies were identified. Conclusions: Incidentally discovered renal cysts in pediatric patients are associated with a small but non-zero risk of ADPKD. Among cyst characteristics, bilaterality, multiplicity, large size, and increased size on follow-up imaging were associated with a statistically significant elevation of ADPKD risk, and should prompt diagnostic evaluation. [ABSTRACT FROM AUTHOR]

Despite the well-established impact of sex and sex hormones on bone structure and density, there has been limited description of sexual dimorphism in the hand and wrist in the literature. We developed a deep convolutional neural network (CNN) model to predict sex based on hand radiographs of children and adults aged between 5 and 70 years. Of the 1531 radiographs tested, the algorithm predicted sex correctly in 95.9% (κ = 0.92) of the cases. Two human radiologists achieved 58% (κ = 0.15) and 46% (κ = − 0.07) accuracy. The class activation maps (CAM) showed that the model mostly focused on the 2nd and 3rd metacarpal base or thumb sesamoid in women, and distal radioulnar joint, distal radial physis and epiphysis, or 3rd metacarpophalangeal joint in men. The radiologists reviewed 70 cases (35 females and 35 males) labeled with sex along with heat maps generated by CAM, but they could not find any patterns that distinguish the two sexes. A small sample of patients (n = 44) with sexual developmental disorders or transgender identity was selected for a preliminary exploration of application of the model. The model prediction agreed with phenotypic sex in only 77.8% (κ = 0.54) of these cases. To the best of our knowledge, this is the first study that demonstrated a machine learning model to perform a task in which human experts could not fulfill. [ABSTRACT FROM AUTHOR]

Background: Severe ulcerative colitis is associated with significant morbidity. Multidetector computed tomography (MDCT) scans are frequently obtained upon hospital admission, but the ability of radiographic findings to predict steroid failure is unknown.Aim: To identify MDCT features predictive of inpatient rescue in hospitalized UC.Methods: Patients hospitalized with UC who underwent a CT scan within 48 h of hospitalization were retrospectively identified. Radiologists blinded to the outcome prospectively evaluated CT scans for the presence of bowel wall thickening, stranding, and hyperenhancement as well as mural stratification, mesenteric hyperemia, and proximal dilation. Logistic regression adjusting for potential confounders was used to test the independent association between radiographic findings and need for rescue therapy.Results: The study cohort included 74 patients. The mean age of the group was 45 years, and two-thirds (66%) were male. Twenty-eight (38%) patients required either inpatient medical rescue or colectomy. The mean number of positive radiographic findings was 4.4 (range 2-6) with a higher median number of findings in those who required rescue therapy (5 vs. 4, p = 0.03). Mural stratification was significantly more common among those who required rescue therapy (92% vs. 49%, p = 0.001). No other radiographic findings were independently associated with inpatient rescue. On multivariable analysis, mural stratification (OR 14.9, 95% CI 2.76-80.2) and number of positive findings (OR 2.10, 95% CI 1.06-4.16) remained independently predictive of the need for rescue therapy.Conclusions: Mural stratification was highly predictive of steroid refractoriness and need for medical or surgical rescue therapy in hospitalized UC. [ABSTRACT FROM AUTHOR]

Background: Oral contrast preparation is fundamental to ensuring diagnostic examination quality for magnetic resonance enterography (MRE), yet little is known about the relative palatability and tolerability of various oral contrast agents in pediatric patients with known or suspected inflammatory bowel disease.Objective: We prospectively compared three MRE oral preparations in pediatric patients with known or suspected Crohn disease with respect to patient-reported tolerability and radiologist-determined small-bowel distension and opacification.Materials and Methods: Seventy-five pediatric patients (mean age 14.8 years, 55% female) with known or suspected Crohn disease referred for MRE were randomized to an oral preparation with a sugar alcohol-based flavored beverage (Breeza), polyethylene glycol preparation (MiraLAX), or low-concentration barium sulfate suspension (VoLumen). Patients were instructed to consume oral contrast agent (using a weight-based protocol) beginning 60 min prior to MRE imaging. Following MRE, patients completed a questionnaire regarding their oral preparation solution including: taste (1-5 scale), feeling of well-being (1-5 scale) and willingness to consume again (yes/no). Two radiologists reviewed all MRE exams and rated exams for global features (active disease, overall small-bowel distention [1-4 scale]) and features specific to individual small-bowel segments (extent of distention, maximal luminal diameter, opacification, and susceptibility artifact). Statistical methods included one-way analysis of variance (ANOVA) with Tukey honest difference and Fisher exact tests.Results: The overall rate of completion of the entire prescribed contrast volume was 53% (40/75), with a significantly higher rate of completion for MiraLAX than for VoLumen (70% vs. 30%, P=0.007). Crossover to a different preparation occurred in nine patients (12%) and was significantly more frequent when the initial preparation was VoLumen versus MiraLAX (29% vs. 0%, P=0.005). Mean subjective taste ratings for both MiraLAX (3.4, P<0.0001) and Breeza (2.8, P=0.006) were superior to those of VoLumen (1.9), which persisted in the subset of patients with MRE evidence of active Crohn disease. Patients who consumed MiraLAX were more likely to be willing to drink it again compared to those consuming VoLumen (82% vs. 46%, P=0.009). Overall small-bowel distention and bowel-segment-specific metrics (distention, maximal diameter, opacification and susceptibility) did not significantly differ among groups.Conclusion: In pediatric patients with known or suspected Crohn disease, MiraLAX and Breeza were rated as more palatable than VoLumen, and all three preparations achieved a similar degree of small-bowel distension and opacification on MRE. Imaging centers performing MRE should stock multiple oral contrast preparations because a sizable proportion of children require more than one agent to ingest the requisite oral contrast volume. [ABSTRACT FROM AUTHOR]

Background: Differentiation of benign from malignant lymphadenopathy remains challenging in pediatric radiology. Textural analysis (TA) quantitates heterogeneity of tissue signal intensities and has been applied to analysis of CT images.Objective: The purpose of this study was to establish whether CT textural analysis of enlarged lymph nodes visualized on pediatric CT can distinguish benign from malignant lymphadenopathy.Materials and Methods: We retrospectively identified enlarged lymph nodes measuring 10-20 mm on contrast-enhanced CTs of patients age 18 years and younger that had been categorized as benign or malignant based on the known diagnoses. We placed regions of interest (ROIs) over lymph nodes of interest and performed textural analysis with and without feature size filtration. We then calculated test performance characteristics for TA features, along with multivariate logistic regression modeling using Akaike Information Criterion (AIC) minimization, to determine the optimal thresholds for distinguishing benign from malignant lymphadenopathy.Results: We identified 34 enlarged malignant nodes and 29 benign nodes from 63 patients within the 10- to 20-mm size range. Filtered image TA exhibited 82.4% sensitivity, 86.2% specificity and 84.1% accuracy for detecting malignant lymph nodes using mean and entropy parameters, whereas unfiltered TA exhibited 88.2% sensitivity, 72.4% specificity and 81.0% accuracy using mean and mean value of positive pixels parameters.Conclusion: This preliminary study demonstrates that the use of TA features improves the utility of pediatric CT to distinguish benign from malignant lymphadenopathy. The addition of TA to pediatric CT protocols has great potential to aid the characterization of indeterminate lymph nodes. If definitive differentiation between benign and malignant lymphadenopathy is possible by TA, it has the potential to reduce the need for follow-up imaging and tissue sampling, with reduced associated radiation exposure. However future studies are needed to confirm the clinical applicability of TA in distinguishing benign from malignant lymphadenopathy. [ABSTRACT FROM AUTHOR]

Objective: Radiographic bone age assessment (BAA) is used in the evaluation of pediatric endocrine and metabolic disorders. We previously developed an automated artificial intelligence (AI) deep learning algorithm to perform BAA using convolutional neural networks. We compared the BAA performance of a cohort of pediatric radiologists with and without AI assistance.Materials and methods: Six board-certified, subspecialty trained pediatric radiologists interpreted 280 age- and gender-matched bone age radiographs ranging from 5 to 18 years. Three of those radiologists then performed BAA with AI assistance. Bone age accuracy and root mean squared error (RMSE) were used as measures of accuracy. Intraclass correlation coefficient evaluated inter-rater variation.Results: AI BAA accuracy was 68.2% overall and 98.6% within 1 year, and the mean six-reader cohort accuracy was 63.6 and 97.4% within 1 year. AI RMSE was 0.601 years, while mean single-reader RMSE was 0.661 years. Pooled RMSE decreased from 0.661 to 0.508 years, all individually decreasing with AI assistance. ICC without AI was 0.9914 and with AI was 0.9951.Conclusions: AI improves radiologist's bone age assessment by increasing accuracy and decreasing variability and RMSE. The utilization of AI by radiologists improves performance compared to AI alone, a radiologist alone, or a pooled cohort of experts. This suggests that AI may optimally be utilized as an adjunct to radiologist interpretation of imaging studies to improve performance. [ABSTRACT FROM AUTHOR]

Objectives: To assess performance of shear wave elastography for evaluation of fibrosis and the histologic stage in patients with autoimmune liver disease (ALD) and to validate previously established advanced fibrosis cutoff values in this cohort. Methods: Shear wave elastography was performed on patients with ALD with an Aixplorer ultrasound system (SuperSonic Imagine, Aix‐en‐Provence, France) using an SC6‐1 transducer. The median estimated tissue Young modulus was calculated from sets of 8 to 10 elastograms. A blinded, subspecialty‐trained pathologist reviewed biopsy specimens. The METAVIR classification was used to stage liver fibrosis and necroinflammation. Steatosis was graded from 0 to 4+. The Kendall τ‐b correlation test was performed to identify the correlation between the estimated tissue Young modulus and fibrosis, steatosis, and the necroinflammatory score. The Spearman correlation test was performed to identify the correlation between the estimated tissue Young modulus and clinical data. The diagnostic performance of shear wave elastography for differentiating METAVIR stage F2 or higher from F0 and F1 fibrosis was evaluated by a receiver operating characteristic (ROC) curve analysis. Results: Fifty‐one patients with ALD were analyzed. The estimated tissue Young modulus was positively correlated with the fibrosis stage and necroinflammation score (r = 0.386; P < .001; r = 0.338; P = .002, respectively) but not steatosis (r = −0.091; P = .527). Serum aspartate aminotransferase, alanine aminotransferase, and total bilirubin values were positively correlated with the estimated tissue Young modulus (r = 0.501; P < .001; r = 0.44; P = .001; r = 0.291; P = .038). The serum albumin value was negatively correlated (r = −0.309; P = .033). The area under the ROC curve was 0.781 (95% confidence interval, 0.641–0.921) for distinguishing F2 or greater fibrosis from F0 and F1 fibrosis. Based on the ROC curve, an optimal cutoff value of 9.15 kPa was identified (sensitivity, 83.3%; specificity, 72.7%). Conclusions: Shear wave elastography is a novel noninvasive adjunct to liver biopsy in evaluation and staging of patients with ALD, showing the potential for serial evaluations of disease progression and treatment responses. [ABSTRACT FROM AUTHOR]

Background: Fetal MRI at 3 T is associated with increased acoustic noise relative to 1.5 T.Objective: The goal of this study is to determine if there is an increased prevalence of congenital hearing loss in neonates who had a 3-T prenatal MR vs. those who had it at 1.5 T.Materials and Methods: We retrospectively identified all subjects who had 3-T fetal MRI between 2012 and 2016 and also underwent universal neonatal hearing screening within 60 days of birth. Fetuses with incomplete hearing screening, magnetic resonance imaging (MRI) studies at both field strengths or fetuses affected by conditions associated with hearing loss were excluded. A random group of controls scanned at 1.5 T was identified. Five subjects had repeat same-strength MRIs (one at 3 T and four at 1.5 T). The pass/fail rate of the transient otoacoustic emissions test and auditory brainstem response test were compared using the Fisher exact test. A logistic regression was performed to assess the effects of other known risk factors for congenital hearing loss.Results: Three hundred forty fetal MRI examinations were performed at 3 T, of which 62 met inclusion criteria. A control population of 1.5-T fetal MRI patients was created using the same exclusion criteria, with 62 patients randomly selected from the eligible population. The fail rates of transient otoacoustic emissions test for the 1.5-T and 3-T groups were 9.7% and 6.5%, respectively, and for the auditory brainstem response test were 3.2% and 1.6%, respectively. There was no significant difference in the fail rate of either test between groups (P=0.74 for transient otoacoustic emissions test, and P=0.8 for auditory brainstem response test). The median gestational age of the 3-T group was 30 weeks, 1 day, significantly higher (P<0.001) than the 1.5-T group (median gestational age: 20 weeks, 2 days).Conclusion: Our findings suggest that the increase in noise associated with 3 T does not increase the rate of clinically detectable hearing abnormalities. [ABSTRACT FROM AUTHOR]

Objective: To develop and assess the value and limitations of an image quality scoring criteria (IQSC) for pediatric CT exams. Methods: IQSC was developed for subjective assessment of image quality using the scoring scale from 0 to 4, with 0 indicating desired anatomy or features not seen, 3 for adequate image quality, and 4 depicting higher than needed image quality. Pediatric CT examinations from 30 separate patients were selected, five each for routine chest, routine abdomen, kidney stone, appendicitis, craniosynostosis, and ventriculoperitoneal (VP) shunt. Five board-certified pediatric radiologists independently performed image quality evaluation using the proposed IQSC. The kappa statistics were used to assess the interobserver variability. Results: All five radiologists gave a score of 3 to two-third (67%) of all CT exams, followed by a score of 4 for 29% of CT exams, and 2 for 4% exams. The median image quality scores for all exams were 3 and the interobserver agreement among five readers (acceptable image quality [scores 3 or 4] vs sub-optimal image quality ([scores 1 and 2]) was moderate to very good (kappa 0.4–1). For all five radiologists, the lesion detection was adequate for all CT exams. Conclusions: The image quality scoring criteria covering routine and some clinical indication-based imaging scenarios for pediatric CT examinations has potential to offer a simple and practical tool for assessing image quality with a reasonable degree of interobserver agreement. A more extensive and multi-centric study is recommended to establish wider usefulness of these criteria. [ABSTRACT FROM AUTHOR]

Purpose: To determine the radiation dose associated with CT-guided percutaneous liver ablations and identify potential risk factors that result in higher radiation doses.Materials and Methods: Between June 2011 and June 2015, 245 consecutive patients underwent 304 CT-guided liver ablation treatments. Patient demographics, tumor characteristics and procedural parameters were identified and analyzed. The peak skin dose and effective dose were assessed for each procedure. Excess relative risk related to radiation effects was calculated. A logistic regression model was prepared by means of stepwise logistic regression to identify variables predictive of increased radiation exposure.Results: Tumor ablations were performed with microwave (n = 220), radiofrequency (n = 74) or irreversible electroporation (IRE) (n = 10). The mean peak skin dose for ablations was 239.2 ± 136.4 mGy, and the mean effective dose was 36.6 ± 22.3 mSv. Of the patient and procedural parameters that were analyzed, increasing weight, use of intravenous contrast and/or hydrodissection during the procedure, together with treatment of multiple lesions in the same sitting were all associated with higher radiation exposure. The mean increase in the absolute risk of fatal malignancy from a single procedure was 0.18% (range 0.02-0.9%). No deterministic skin changes were identified in the patient cohort.Conclusion: The overall risk of stochastic and deterministic effects from radiation associated with CT-guided ablations is low compared with other inherent procedural complications. This study identifies several factors that are associated with higher radiation dose in percutaneous liver ablation procedures. [ABSTRACT FROM AUTHOR]