Practical Guide to VI-RADS: MRI Protocols, Lesion Characterization, and Pitfalls.

Urothelial carcinoma is the most common type of bladder cancer (BC), accounting for approximately 90% of all cases. Evaluating the depth of tumor invasion in the bladder wall (tumor staging) is essential for determining the treatment and prognosis in patients with BC. Neoadjuvant therapy followed by radical cystectomy is the most common treatment of localized muscle-invasive BC (MIBC). Therefore, it is vital to differentiate non-MIBC from MIBC. Transurethral resection of bladder tumor (TURBT) is the reference standard to determine the extent of tumor invasion into the bladder wall through tissue sampling. However, this diagnostic and therapeutic method may not adequately sample the muscularis propria, leading to a higher risk of residual disease, early recurrence, and tumor understaging in approximately 50% of patients during the initial TURBT. Multiparametric MRI can overcome some of the limitations of TURBT when evaluating BC, particularly regarding tumor staging. In this context, the Vesical Imaging Reporting and Data System (VI-RADS) classification was developed to establish standards for bladder multiparametric MRI and interpretation. It uses a 5-point scale to assess the likelihood of detrusor muscle invasion. T2-weighted MR images are particularly useful as an initial guide, especially for categories 1-3, while the presence of muscular invasion is determined with diffusion-weighted and dynamic contrast-enhanced sequences. Diffusion-weighted imaging takes precedence as the dominant method when optimal image quality is achieved. The presence of a stalk or a thickened inner layer and no evidence of interruption of the signal intensity of the muscular layer are central for predicting a low likelihood of muscle invasion. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material. See the invited commentary by Hoegger in this issue.

Setting up regional diagnostic reference levels for pediatric computed tomography in Latin America: preliminary results, challenges and the work ahead.

We established a framework for collecting radiation doses for head, chest and abdomen-pelvis computed tomography (CT) in children scanned at multiple imaging sites across Latin America with an aim towards establishing diagnostic reference levels (DRLs) and achievable doses (ADs) in pediatric CT in Latin America. Our study included 12 Latin American sites (in Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Honduras and Panama) contributing data on the four most common pediatric CT examinations (non-contrast head, non-contrast chest, post-contrast chest and post-contrast abdomen-pelvis). Sites contributed data on patients' age, sex and weight, scan factors (tube current and potential), volume CT dose index (CTDIvol) and dose length product (DLP). Data were verified, leading to the exclusion of two sites with missing or incorrect data entries. We estimated overall and site-specific 50th (AD) and 75th (diagnostic reference level [DRL]) percentile CTDIvol and DLP for each CT protocol. Non-normal data were compared using the Kruskal-Wallis test. Sites contributed data from 3,934 children (1,834 females) for different CT exams (head CT 1,568/3,934, 40%; non-contrast chest CT 945/3,934, 24%; post-contrast chest CT 581/3,934, 15%; abdomen-pelvis CT 840/3,934, 21%). There were significant statistical differences in 50th and 75th percentile CTDIvol and DLP values across the participating sites (P<0.001). The 50th and 75th percentile doses for most CT protocols were substantially higher than the corresponding doses reported from the United States of America. Our study demonstrates substantial disparities and variations in pediatric CT examinations performed in multiple sites in Latin America. We will use the collected data to improve scan protocols and perform a follow-up CT study to establish DRLs and ADs based on clinical indications.

VI-RADS for Bladder Cancer: Current Applications and Future Developments.

Bladder cancer (BCa) is among the ten most frequent cancers globally. It is the tumor with the highest lifetime treatment-associated costs, and among the tumors with the heaviest impacts on postoperative quality of life. The purpose of this article is to review the current applications and future perspectives of the Vesical Imaging Reporting and Data System (VI-RADS). VI-RADS is a newly developed scoring system aimed at standardization of MRI acquisition, interpretation, and reporting for BCa. An insight will be given on the BCa natural history, current MRI applications for local BCa staging with assessment of muscle invasiveness, and clinical implications of the score for disease management. Future applications include risk stratification of nonmuscle invasive BCa, surveillance, and prediction and monitoring of therapy response. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY STAGE: 2.

Early Renin Recovery After Adrenalectomy in Aldosterone-Producing Adenomas: A Prospective Study.

The aim of the study was to clarify the relationship and the time of aldosterone and renin recoveries at immediate and long-term follow-up in aldosterone-producing adenoma (APA) patients who underwent adrenalectomy. Prospective and longitudinal protocol in a cohort of APA patients was followed in a single center. Among 43 patients with primary aldosteronism (PA), thirteen APA patients were enrolled in this study. Blood was collected for aldosterone, renin, potassium, creatinine, cortisol, and ACTH before and 1, 3, 5, 7, 15, 30, 60, 90, 120, 180, 270, 360 days after adrenalectomy. At diagnosis, most patients (84%) had hypokalemia and high median aldosterone levels (54.8; 24.0-103 ng/dl) that decreased to undetectable (<2.2) or very low (<3.0) levels between fifth to seventh days after surgery; then, between 3-12 months, its levels gradually increased to the lower normal range. The suppressed renin (2.3; 2.3-2.3 mU/l) became detectable between the fifteen and thirty days after surgery, remaining normal throughout the study. The aldosterone took longer than renin to recover (60 vs.15 days; p<0.002) and patients with higher aldosterone had later recovery (p=0.03). The cortisol/ACTH levels remained normal despite the presence of a post-operative hypoaldosteronism. Blood pressure and antihypertensive requirement decreased after adrenalectomy. In conclusion, our prospective study shows the borderline persistent post-operative hypoaldosteronism in the presence of early renin recovery indicating incapability of the zona glomerulosa of the remaining adrenal gland to produce aldosterone. These findings contribute to the comprehension of differences in renin and aldosterone regulation in APA patients, although both are part of the same interconnected system.

Prostate MRI Qualification: AJR Expert Panel Narrative Review.

Prostate MRI is now established as a first-line investigation for individuals presenting with suspected localized or locally advanced prostate cancer. Successful delivery of the MRI-directed pathway for prostate cancer diagnosis relies on high-quality imaging as well as the interpreting radiologist's experience and expertise. Radiologist certification in prostate MRI may help limit interreader variability, optimize outcomes, and provide individual radiologists with documentation of meeting predefined standards. This AJR Expert Panel Narrative Review summarizes existing certification proposals, recognizing variable progress across regions in establishing prostate MRI certification programs. To our knowledge, Germany is the only country with a prostate MRI certification process that is currently available for radiologists. However, prostate MRI certification programs have also recently been proposed in the United States and United Kingdom and by European professional society consensus panels. Recommended qualification processes entail a multifaceted approach, incorporating components such as minimum case numbers, peer learning, course participation, continuing medical education credits, and feedback from pathology results. Given the diversity in health care systems, including in the provision and availability of MRI services, national organizations will likely need to take independent approaches to certification and accreditation. The relevant professional organizations should begin developing these programs or continue existing plans for implementation.

VI-RADS score system - A primer for urologists.

Bladder cancer (BCa) is one of the most common cancers worldwide and is also considered to be one of the most relapsing and aggressive neoplasms. About 30% of patients will present with muscle invasive disease, which is associated with a higher risk for metastatic disease. The aim of this article is to review the state of art imaging in Radiology, while providing a complete guide to urologists, with case examples, for the rationale of the development of the Vesical Imaging Reporting and Data System (VI-RADS), a scoring system emphasizing a standardized approach to multiparametric Magnetic Resonance Imaging (mpMRI) acquisition, interpretation, and reporting for BCa. Also, we examine relevant external validation studies and the consolidated literature of mpMRI for bladder cancer. In addition, this article discusses some of the potential clinical implications of this scoring system for disease management and follow-up.

Use of Chest Imaging in the Diagnosis and Management of COVID-19: A WHO Rapid Advice Guide.

The World Health Organization (WHO) undertook the development of a rapid guide on the use of chest imaging in the diagnosis and management of coronavirus disease 2019 (COVID-19). The rapid guide was developed over 2 months by using standard WHO processes, except for the use of "rapid reviews" and online meetings of the panel. The evidence review was supplemented by a survey of stakeholders regarding their views on the acceptability, feasibility, impact on equity, and resource use of the relevant chest imaging modalities (chest radiography, chest CT, and lung US). The guideline development group had broad expertise and country representation. The rapid guide includes three diagnosis recommendations and four management recommendations. The recommendations cover patients with confirmed or who are suspected of having COVID-19 with different levels of disease severity, throughout the care pathway from outpatient facility or hospital entry to home discharge. All recommendations are conditional and are based on low certainty evidence (n = 2), very low certainty evidence (n = 2), or expert opinion (n = 3). The remarks accompanying the recommendations suggest which patients are likely to benefit from chest imaging and what factors should be considered when choosing the specific imaging modality. The guidance offers considerations about implementation, monitoring, and evaluation, and also identifies research needs. Published under a CC BY 4.0 license. Online supplemental material is available for this article.

An international expert opinion statement on the utility of PET/MR for imaging of skeletal metastases.

BACKGROUND: MR is an important imaging modality for evaluating musculoskeletal malignancies owing to its high soft tissue contrast and its ability to acquire multiparametric information. PET provides quantitative molecular and physiologic information and is a critical tool in the diagnosis and staging of several malignancies. PET/MR, which can take advantage of its constituent modalities, is uniquely suited for evaluating skeletal metastases. We reviewed the current evidence of PET/MR in assessing for skeletal metastases and provided recommendations for its use. METHODS: We searched for the peer reviewed literature related to the usage of PET/MR in the settings of osseous metastases. In addition, expert opinions, practices, and protocols of major research institutions performing research on PET/MR of skeletal metastases were considered. RESULTS: Peer-reviewed published literature was included. Nuclear medicine and radiology experts, including those from 13 major PET/MR centers, shared the gained expertise on PET/MR use for evaluating skeletal metastases and contributed to a consensus expert opinion statement. [18F]-FDG and non [18F]-FDG PET/MR may provide key advantages over PET/CT in the evaluation for osseous metastases in several primary malignancies. CONCLUSION: PET/MR should be considered for staging of malignancies where there is a high likelihood of osseous metastatic disease based on the characteristics of the primary malignancy, hight clinical suspicious and in case, where the presence of osseous metastases will have an impact on patient management. Appropriate choice of tumor-specific radiopharmaceuticals, as well as stringent adherence to PET and MR protocols, should be employed.

Profile of Articles Published in AJR From 2014 to 2018 and Potential Association With Bibliometric Parameters.

OBJECTIVE. The purpose of this study was to assess the profile of articles published in the American Journal of Roentgenology (AJR) and potential associations with bibliometric indexes over a 5-year period. MATERIALS AND METHODS. Citable documents published from 2014 to 2018 were retrieved from the Journal Citation Reports database. Six bibliometric indexes were assessed. The following article parameters were retrieved: type, subspecialty (17 topics covered by AJR), origin, and title. Differences between groups were assessed by t test, ANOVA, Kruskal-Wallis test, or chi-square test. Citability was assessed by regression analysis. RESULTS. After exclusions, 2210 articles were considered citable and included in the analyses. Most of the metrics improved slightly, except for the Eigenfactor score and article influence score, which decreased. Original articles were preponderant; AJR published significantly more review articles than did three other general radiology journals. The mean number of citations per year of original articles (2.03 ± 2.18) was significantly larger than that of review articles (2.06 ± 2.47) (p = .02). The mean number of citations per year was significantly higher for articles with mixed-origin authorship (3.12 ± 3.19) than for articles with American (2.02 ± 2.17) or non-American (1.93 ± 2.26) authors only (p < .001). The distributions of mean number of citations per year among subspecialties differed significantly (p = .001). Articles on abdominal, musculoskeletal, pediatric, and women's imaging were more frequently cited. Multivariate regression analysis showed that subspecialty and presence of acronyms or initialisms in the title were the only independent predictors of citability (both, p = .001). CONCLUSION. The main AJR bibliometric indexes increased slightly from 2014 to 2018, except for those from the Eigenfactor Project. The presence of acronyms or initialisms in the title and subspecialty were the only independent predictors of citability.

Pelvic floor muscles after prostate radiation therapy: morpho-functional assessment by magnetic resonance imaging, surface electromyography and digital anal palpation.

AIM: To evaluate the radiotherapy (RT) effect in the pelvic floor muscles (PFM) function in men with prostate cancer (PC). MATERIALS AND METHODS: A cross-sectional study included three groups of patients with PC and RT indication: 1) Pre-RT group: evaluated before the beginning of RT; 2) Acute group: evaluated between six months and one year after RT; 3) Late Group: evaluated between two and a half years and four years post-RT. PFM assessment was divided into: a) functional assessment through the digital anal palpation (Modified Oxford Scale) and surface electromyography (sEMG) with anal probe; b) anatomical assessment by pelvic magnetic resonance imaging (MRI) with thickness measurements of levator ani muscle and pelvic specific parameters at rest and under Valsalva maneuver. We used Student t test, considering as significant p <0.05. RESULTS: Thirty-three men were assessed: Pre-RT (n=12); Acute (n=10) and Late (n=11) groups. PFM functional assessment showed Late group with lower electromyographic activity, especially in the sustained contractions when compared to the Pre-RT (p=0.003) and Acute groups (p=0.006). There was no significant difference between groups in MRI. CONCLUSION: PFM functional assessment showed a decrease in sEMG activity in the Late group post-RT. Most of the sample (72.7%) did not know how to actively contract the PFM or had a weak voluntary contraction when assessed by digital anal palpation. Also, these patients presented higher prevalence of pelvic complaints. No changes were observed in the morpho-functional parameters evaluated by MRI, except the measurement of the membranous urethra length when comparing Pre-RT Group and Acute and Late Groups.

Independent external validation of nomogram to predict extracapsular extension in patients with prostate cancer.

INTRODUCTION: The objective of this study was to perform an independent external validation of the Giganti-Coppola nomogram (GCN), which uses clinical and radiological parameters to predict prostate extracapsular extension (ECE) on the final pathology of patients undergoing radical prostatectomy (RP). MATERIAL AND METHODS: Seventy-two patients diagnosed with prostate cancer (PCa), who were RP candidates from two institutions, were prospectively included. All patients underwent preoperative multi-parametric magnetic resonance imaging (mpMRI) at 1.5 T, without the use of an endorectal coil, with multiplanar images in T1WI, T2WI, DWI, and DCE. The AUC and a calibration graph were used to validate the nomogram, using the regression coefficients of the Giganti-Coppola study. RESULTS: The original nomogram had an AUC of 0.90 (p = 0.001), with a sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 100%, 5.1%, 47.1%, 100%, and 48%, respectively. The calibration graph showed an overestimation of the nomogram for ECE. CONCLUSION: The GCN has an adequate ability in predicting ECE; however, in our sample, it showed limited accuracy and overestimated likelihood of ECE in the final pathology of patients with PCa submitted to RP. KEY POINTS: • Knowledge of preoperative local staging of prostate cancer is essential for surgical treatment. Extracapsular extension increases the chance of positive surgical margins. • Imaging modalities such as mpMRI alone does not have suitable accuracy in local staging. • Giganti-Coppola's nomogram achieved an adequate ability in predicting ECE.

Overview of VI-RADS in Bladder Cancer.

OBJECTIVE. The purpose of this article is to review the natural history and management of bladder cancer, with insight into MRI applications for the assessment of muscle invasiveness of bladder cancer using the newly developed Vesical Imaging Reporting and Data System (VI-RADS) score. CONCLUSION. Multiparametric MRI and the VI-RADS score have been consistently validated across several different institutions as appropriate tools for local staging of bladder cancer and have been proven to contribute to the diagnostic workup and management of urinary bladder cancer.

Prevalence of Vas Deferens Calcifications on Abdominal CT Examinations and Association With Systemic Conditions.

OBJECTIVE. The purpose of this study was to describe the prevalence of vas deferens (VD) calcifications on abdominal CT examinations and the associations between VD calcifications and several systemic conditions. MATERIALS AND METHODS. The CT examinations of male patients from January 2010 to December 2011 were retrospectively reviewed. After exclusions, the records of 1915 consecutively identified patients were analyzed. Five readers, 3rd- and 4th-year radiology residents, recorded the presence and laterality of VD calcifications and of vascular calcifications presumed due to atherosclerosis. A sixth reader parsed the patient records for diagnoses of type 2 diabetes mellitus (DM) and chronic kidney disease (CKD). RESULTS. The mean age of the entire sample population was 52.9 ± 18.9 years (range, 1-93 years). The mean age of patients with VD calcifications was 59.3 ± 12.0 (SD) years and of the group without VD calcifications was 52.9 ± 19.1 years (p = 0.17). The prevalence of VD calcification was 1.61% (31 patients): 21 (67.7%) of the patients had bilateral calcification; seven (22.6%), right-sided only; and three, (9.7%) left-sided. The frequency of DM was 28.8% (551/1915), of CKD was 7.58% (150/1915), and of atherosclerosis, 60.4% (1156/1915). The mean caliber of calcified VDs was 5.31 ± 1.29 mm versus 3.63 ± 0.63 mm for patients without calcification or any chronic condition (p < 0.0001). Among age, atherosclerosis, DM, and CKD in univariate regression analysis, only DM was associated with VD calcification (p = 0.006). However, because age (p = 0.063) and atherosclerosis (p = 0.057) were close to significant, they were included in the multivariate analysis, which also showed only DM associated with VD calcification (odds ratio, 2.14 ± 0.85). CONCLUSION. In the large cohort in this study, the prevalence of VD calcification was 1.61%. VD calcification was strongly associated with DM. The pathologic implications of VD calcification remain unclear and warrant further investigation in prospective longitudinal studies.

Histogram Analysis of Adrenal Lesions With a Single Measurement for 10th Percentile: Feasibility and Incremental Value for Diagnosing Adenomas.

OBJECTIVE: Our purpose was to assess whether histogram analysis of adrenal lesions from a single measurement of mean attenuation and SD, using a threshold of 10% of negative voxels, can replace voxel counting while maintaining diagnostic accuracy. MATERIALS AND METHODS: In a 4-year period, 325 adrenal lesions were detected on CT examinations of 308 consecutive patients. After exclusions, 91 patients with 108 lesions, including 20 malignant lesions and 88 adenomas (defined by histologic results or follow-up), were enrolled. Two observers retrospectively measured lesion size, mean attenuation value, and SD attenuation value and generated a pixel histogram. The 10th percentile (P10) was obtained from the conventional histogram analysis and was also calculated from the following formula: P10 = mean attenuation - (1.282 × SD). Diagnostic accuracies of the mean attenuation criterion, histogram analysis, and calculated 10th percentile were compared. RESULTS: The study group was composed of 74 patients with 88 adenomas and 17 patients with 20 malignant lesions, including seven adrenocortical carcinomas and 13 metastases; 93.1% of histograms showed normal distribution. The correlation between histogram analysis and calculated 10th percentile was 0.9827 and 0.9843 for reader 1 and 2 (p < 0.00001 for both). For both readers, sensitivity and specificity of the mean attenuation analysis were 65.9% (95% CI, 55.0-75.7%) and 100.0% (95% CI, 83.2-100%). The sensitivity and specificity of histogram analysis and calculated 10th percentile were the same, 87.5% (95% CI, 78.7-93.6%) and 95.0% (95% CI, 75.1-99.8%), for both readers. The increment increase in sensitivity was significant (p < 0.001), whereas the decrease in specificity was not (p = 0.15). CONCLUSION: For most adrenal lesions, the pixel attenuation has a gaussian distribution, allowing estimation of 10th percentile with a single measurement. The accuracy of histogram analysis and calculated 10th percentile outperformed the mean attenuation as a diagnostic criterion for nonfunctioning adenomas.

Incremental value of MRI for preoperative penile cancer staging.

PURPOSE: To evaluate the incremental value of magnetic resonance imaging (MRI), compared to clinical examination, for penile cancer (PC) local staging. MATERIALS AND METHODS: Twenty-five consecutive patients with histologically proven PC were evaluated prospectively. MRI staging was performed on 1.5 and 3.0T scanners using high-resolution T2 -weighted and postcontrast T1 -weighted images. Two blinded observers interpreted MR images. Clinical local staging was performed by experienced urologists. The pathology report was used as the standard of reference. RESULTS: The interobserver agreement for MRI staging, using a kappa test for T-staging was moderate, 0.52 (95% confidence interval [CI] = 0.24-0.78), P = 0.001, although a high correlation for N-staging, 0.72 (95% CI = 0.42-1.00), P = 0.001, was detected. Clinical staging was correct in 52.0% (13/25) of patients. After pathological staging, five (20.0%) lesions were upstaged and seven (28.0%) lesions were downstaged compared to clinical examination. MRI accurately defined T-staging in 18/25 lesions (72.0%). After pathologic staging, five (20.0%) were upstaged and two downstaged (8.0%), compared to MRI. Fifteen patients were submitted to inguinal and pelvic lymphadenectomy and considered for comparison of accuracy of nodal staging by physical examination and MRI. Clinical staging accurately staged 7/15 patients (46.7%). After histopathologic analysis, six cases had nodal staging upgraded and two cases were downgraded. MRI correctly staged 13/15 (86.7%). Using a chi-square for comparison, differences in proportion of corrected staging between clinical examination and MRI were not significant for T-staging (P = 0.14), but were significant for nodal staging (P = 0.02). CONCLUSION: According to our results, MRI improves local staging of PC patients, particularly for those with limited physical examination. LEVEL OF EVIDENCE: 1 J. Magn. Reson. Imaging 2017;45:118-124.