Percentage of Pancreatic Cysts on MRI With a Pancreatic Carcinoma: Systematic Review and Meta-Analysis.

BACKGROUND: Pancreatic cystic lesions (PCLs) are frequent on MRI and are thought to be associated with pancreatic adenocarcinoma (PDAC) necessitating long-term surveillance based on older studies suffering from selection bias. PURPOSE: To establish the percentage of patients with PCLs on MRI with a present or future PDAC. STUDY TYPE: Systematic review, meta-analysis. POPULATION: Adults with PCLs on MRI and a present or future diagnosis of PDAC were eligible. MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Scopus were searched to April 2022 (PROSPERO:CRD42022320502). Studies limited to PCLs not requiring surveillance, <100 patients, or those with a history/genetic risk of PDAC were excluded. FIELD STRENGTH/SEQUENCE: ≥1.5 T with ≥1 T2-weighted sequence. ASSESSMENT: Two investigators extracted data, with discrepancies resolved by a third. QUADAS-2 assessed bias. PDAC was diagnosed using a composite reference standard. STATISTICAL TESTS: A meta-analysis of proportions was performed at the patient-level with 95% confidence intervals (95% CI). RESULTS: Eight studies with 1289 patients contributed to the percentage of patients with a present diagnosis of PDAC, and 10 studies with 3422 patients to the percentage with a future diagnosis. Of patients with PCLs on MRI, 14.8% (95% CI 2.4-34.9) had a PDAC at initial MRI, which decreased to 6.0% (2.2-11.3) for studies at low risk of bias. For patients without PDAC on initial MRI, 2.0% (1.1-3.2) developed PDAC during surveillance, similar for low risk of bias studies at 1.9% (0.7-3.6), with no clear trend of increased PDAC for longer surveillance durations. For patients without worrisome features or high-risk stigmata, 0.9% (0.1-2.2) developed PDAC during surveillance. Of 10, eight studies had a median surveillance ≥3 years (range 3-157 months). Sources of bias included retrospectively limiting PCLs to those with histopathology and inconsistent surveillance protocols. DATA CONCLUSION: A low percentage of patients with PCLs on MRI develop PDAC while on surveillance. The first MRI revealing a PCL should be scrutinized for PDAC. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

Clinical Impact of Cardiac MRI T1 and T2 Parametric Mapping in Patients with Suspected Cardiomyopathy.

Background There are limited data on the incremental value of parametric mapping compared with core cardiac MRI protocols for suspected cardiomyopathy in routine clinical practice. Purpose To evaluate the impact of cardiac MRI T1 and T2 mapping in routine clinical practice with respect to diagnostic accuracy, reader diagnostic confidence, and downstream cardiac imaging utilization. Materials and Methods In this retrospective single-center study, consecutive clinical cardiac MRI scans obtained with and without T1 and T2 mapping for evaluation of suspected cardiomyopathy between January 2017 and October 2019 were evaluated. Diagnostic accuracy and reader diagnostic confidence were evaluated in a random subset. Downstream cardiac imaging utilization was analyzed in patients with a minimum of 1 year of clinical follow-up ending before January 2020. Results A total of 1876 patients (mean age, 51 years ± 17 [SD]; 1113 men) were evaluated. Of these, 751 (40%) underwent cardiac MRI with the core protocol and 1125 (60%) with the core protocol plus T1 and T2 mapping. In the mapping group, T1 and T2 were high in 280 (25%) and 47 patients (4%), respectively. In the subset evaluated for diagnostic utility (n = 450), the addition of T1 and T2 maps to the core protocol resulted in an improvement in reader diagnostic confidence in 174 patients (39%). Diagnostic sensitivity was higher with the core protocol plus mapping compared with the core protocol alone for myocarditis (89% [31 of 35 patients] vs 69% [24 of 35]; P = .008), Fabry disease (93% [13 of 14 patients] vs 50% [seven of 14]; P = .01), and amyloidosis (100% [16 of 16 patients] vs 63% [10 of 16]; P = .01). In the subset evaluated for downstream imaging utilization (n = 903), 47% of patients with mapping had at least one subsequent cardiac imaging test compared with 55% of patients without mapping (P = .01). Conclusion In patients with suspected cardiomyopathy, cardiac MRI with T1 and T2 mapping had high diagnostic utility and was associated with lower downstream cardiac imaging utilization. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Jerosch-Herold and Coelho-Filho in this issue.

Total Kidney Volume Measurements in ADPKD by 3D and Ellipsoid Ultrasound in Comparison with Magnetic Resonance Imaging.

BACKGROUND AND OBJECTIVES: Total kidney volume is a validated prognostic biomarker for autosomal dominant polycystic kidney disease. Total kidney volume by magnetic resonance imaging (MRI) and manual segmentation is considered the "reference standard," but it is time consuming and not readily accessible. By contrast, three-dimensional (3D) ultrasound provides a promising technology for total kidney volume measurements with unknown potential. Here, we report a comparative study of total kidney volume measurements by 3D ultrasound versus the conventional methods by ultrasound ellipsoid and MRI ellipsoid. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: This single-center prospective study included 142 patients who completed a standardized 3D ultrasound and MRI. Total kidney volumes by 3D ultrasound and ultrasound ellipsoid were compared with those by MRI. We assessed the agreement of total kidney volume measurements by Bland-Altman plots and misclassification of the Mayo Clinic imaging classes between the different imaging methods, and we assessed prediction of Mayo Clinic imaging classes 1C-1E by average ultrasound kidney length >16.5 cm. RESULTS: Compared with MRI manual segmentation, MRI ellipsoid, 3D ultrasound, and ultrasound ellipsoid underestimated total kidney volume (mean difference: -3%, -9%, and -11%, respectively), with Mayo Clinic imaging classes misclassified in 11%, 21%, and 22% of patients, respectively; most misclassified cases by MRI ellipsoid (11 of 16), 3D ultrasound (23 of 30), and ultrasound ellipsoid (26 of 31) were placed into a lower Mayo Clinic imaging class. Predictions of the high-risk Mayo Clinic imaging classes (1C-1E) by MRI ellipsoid, 3D ultrasound, and ultrasound ellipsoid all yielded high positive predictive value (96%, 95%, and 98%, respectively) and specificity (96%, 96%, and 99%, respectively). However, both negative predictive value (90%, 88%, and 95%, respectively) and sensitivity (88%, 85%, and 94%, respectively) were lower for 3D ultrasound and ultrasound ellipsoid compared with MRI ellipsoid. An average ultrasound kidney length >16.5 cm was highly predictive of Mayo Clinic imaging classes 1C-1E only in patients aged ≤45 years. CONCLUSIONS: Total kidney volume measurements in autosomal dominant polycystic kidney disease by 3D ultrasound and ultrasound ellipsoid displayed similar bias and variability and are less accurate than MRI ellipsoid. Prediction of high-risk Mayo Clinic imaging classes (1C-1E) by all three methods provides high positive predictive value, but ultrasound ellipsoid is simpler to use and more readily available.

Lessons Learned From the Effects of COVID-19 on the Training and Education Workflow of Radiology Residents-A Time for Reflection: Perspectives of Residency Program Directors and Residents in Canada.

PURPOSE: The coronavirus disease 2019 (COVID-19) pandemic has led to widespread changes in all health care settings including academic radiology departments. The purpose of this survey-based study was to investigate the impact of COVID-19 on radiology resident training and education workflow in Canada in terms of the nature, scale, and heterogeneity of the changes, preparedness and adaptation, and perceptions of the present and future of radiology training. METHODS: A 30-question web-based survey was sent to 17 radiology residency program directors across Canada. A separate 32-question survey was sent to 460 residents currently enrolled in a radiology residency in Canada. These surveys were open for 3 weeks. RESULTS: We received responses from 16 program directors and 80 residents (response rates 94.1% and 17.4%, respectively). Most respondents agreed that objectives were being met for knowledge and interpretation but less so for case volumes and technical skills. Less time was allotted for on-site activities (eg, readouts) with more time for off-site activities (eg, videoconferencing). Daytime rotations were at least partly cancelled. Most respondents felt these changes were met with enthusiasm by both faculty and residents. However, there were perceived challenges including lack of training on virtual platforms for delivery of teaching and decreased staff-resident interaction, with short- and long-term anxiety reported. CONCLUSIONS: The coronavirus disease 2019 has dramatically changed radiology resident training in Canada, with increased virtual learning at the expense of cancelled rotations and the resultant reduction in case volumes and staff-resident interaction. Although adopted with enthusiasm, these changes present substantial challenges and anxiety regarding the future of radiology resident education.

Intraventricular ganglioglioma with extensive hemorrhage.

Gangliogliomas represent a rare form of neuroepithelial tumor (up to 1.3% of brain tumors [1]), which even more rarely present with hemorrhage or localize intraventricularly. To date, only two cases of ganglioglioma with both of these features have been reported. Our patient is a 23-year-old woman who presented with signs and symptoms of increased intracranial pressure (ICPI), with a post-subtotal resection diagnosis of WHO Grade I ganglioglioma localizing bilaterally to the lateral ventricles. One year following the operation, the tumor showed radiologic evidence of interval hemorrhage, which was verified histopathologically following a second subtotal resection. Greater than 95% of the lesion represented a large hematoma with organization and well-defined fibrous pseudo-capsule, with very scanty fragments of adjacent/peripheral low-grade neuroglial tumor. This case represents a very rare presentation of intraventricular ganglioglioma with extensive hemorrhage.
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Copy number variable microRNAs in schizophrenia and their neurodevelopmental gene targets.

BACKGROUND: MicroRNAs (miRNAs) are key regulators of gene expression in the human genome and may contribute to risk for neuropsychiatric disorders. miRNAs play an acknowledged role in the strongest of genetic risk factors for schizophrenia, 22q11.2 deletions. We hypothesized that in schizophrenia there would be an enrichment of other rare copy number variants (CNVs) that overlap miRNAs. METHODS: Using high-resolution genome-wide microarrays and rigorous methods, we compared the miRNA content of rare CNVs in well-characterized cohorts of schizophrenia cases (n = 420) and comparison subjects, excluding 22q11.2 CNVs. We also performed a gene-set enrichment analysis of the predicted miRNA target genes. RESULTS: The schizophrenia group was enriched for the proportion of individuals with a rare CNV overlapping a miRNA (3.29-fold increase over comparison subjects, p < .0001). The presence of a rare CNV overlapping a miRNA remained a significant predictor of schizophrenia case status (p = .0072) in a multivariate logistic regression model correcting for total CNV size. In contrast, comparable analyses correcting for CNV size showed no enrichment of rare CNVs overlapping protein-coding genes. A gene-set enrichment analysis indicated that predicted target genes of recurrent CNV-overlapped miRNAs in schizophrenia may be functionally enriched for neurodevelopmental processes, including axonogenesis and neuron projection development. Predicted gene targets driving these results included CAPRIN1, NEDD4, NTRK2, PAK2, RHOA, and SYNGAP1. CONCLUSIONS: These data are the first to demonstrate a genome-wide role for CNVs overlapping miRNAs in the genetic risk for schizophrenia. The results provide support for an expanded multihit model of causation, with potential implications for miRNA-based therapeutics.

MicroRNA Dysregulation, Gene Networks, and Risk for Schizophrenia in 22q11.2 Deletion Syndrome.

The role of microRNAs (miRNAs) in the etiology of schizophrenia is increasingly recognized. Microdeletions at chromosome 22q11.2 are recurrent structural variants that impart a high risk for schizophrenia and are found in up to 1% of all patients with schizophrenia. The 22q11.2 deletion region overlaps gene DGCR8, encoding a subunit of the miRNA microprocessor complex. We identified miRNAs overlapped by the 22q11.2 microdeletion and for the first time investigated their predicted target genes, and those implicated by DGCR8, to identify targets that may be involved in the risk for schizophrenia. The 22q11.2 region encompasses seven validated or putative miRNA genes. Employing two standard prediction tools, we generated sets of predicted target genes. Functional enrichment profiles of the 22q11.2 region miRNA target genes suggested a role in neuronal processes and broader developmental pathways. We then constructed a protein interaction network of schizophrenia candidate genes and interaction partners relevant to brain function, independent of the 22q11.2 region miRNA mechanisms. We found that the predicted gene targets of the 22q11.2 deletion miRNAs, and targets of the genome-wide miRNAs predicted to be dysregulated by DGCR8 hemizygosity, were significantly represented in this schizophrenia network. The findings provide new insights into the pathway from 22q11.2 deletion to expression of schizophrenia, and suggest that hemizygosity of the 22q11.2 region may have downstream effects implicating genes elsewhere in the genome that are relevant to the general schizophrenia population. These data also provide further support for the notion that robust genetic findings in schizophrenia may converge on a reasonable number of final pathways.