American College Of Radiology Research Articles

Impact and effect of imaging referral guidelines on patients and radiology services: a systematic review.

The objective of this systematic review was to offer a comprehensive overview and explore the associated outcomes from imaging referral guidelines on various key stakeholders, such as patients and radiologists. An electronic database search was conducted in Medline, Embase and Web of Science to retrieve citations published between 2013 and 2023. The search was constructed using medical subject headings and keywords. Only full-text articles and reviews written in English were included. The quality of the included papers was assessed using the mixed methods appraisal tool. A narrative synthesis was undertaken for the selected articles. The search yielded 4384 records. Following the abstract, full-text screening, and removal of duplication, 31 studies of varying levels of quality were included in the final analysis. Imaging referral guidelines from the American College of Radiology were most commonly used. Clinical decision support systems were the most evaluated mode of intervention, either integrated or standalone. Interventions showed reduced patient radiation doses and waiting times for imaging. There was a general reduction in radiology workload and utilisation of diagnostic imaging. Low-value imaging utilisation decreased with an increase in the appropriateness of imaging referrals and ratings and cost savings. Clinical effectiveness was maintained during the intervention period without notable adverse consequences. Using evidence-based imaging referral guidelines improves the quality of healthcare and outcomes while reducing healthcare costs. Imaging referral guidelines are one essential component of improving the value of radiology in the healthcare system. There is a need for broader dissemination of imaging referral guidelines to healthcare providers globally in tandem with the harmonisation of the application of these guidelines to improve the overall value of radiology within the healthcare system. The application of imaging referral guidelines has an impact and effect on patients, radiologists, and health policymakers. The adoption of imaging referral guidelines in clinical practice can impact healthcare costs and improve healthcare quality and outcomes. Implementing imaging referral guidelines contributes to the attainment of value-based radiology.

Role of Macrocalcification in Raising the Suspicion of Malignancy among the ACR TIRADS Thyroid Nodules Detected by Ultrasonography

Abstract Background Thyroid nodules are a frequent finding on neck sonography. The US is the most commonly used imaging technique for the evaluation of thyroid nodules. The Thyroid Imaging, Reporting and Data System (TIRADS) developed by the American college of radiology (ACR) for classification of thyroid nodules is a practical and convenient method for risk stratification of thyroid malignancy, based on allocating points for different sonographic features of thyroid nodules in five morphologic categories (composition, echogenicity, margins, shape, and presence of echogenic foci). Objective To evaluate the role of macrocalcification in raising the suspicious of malignancy among ACR TIRADS 3 and 4 group without macrocalcification Patients and Methods Our study was conducted on 60 adult patients, 20 patients with TIRADS 3 nodule, 20 patients with TIRADS 4 group with macrocalcification nodules and 20 patients group TIRADS 4 without macrocalcification nodules, whose ages range between 23 and 65 years old and were referred to undergo FNA procedures. Results The present study concludes parenchymal macrocalcifications showed no statistically significant difference in raising percentage of malignancy among TIRADS 4 patients. Conclusion We conclude that the added macrocalcification showed no statistically significant difference in raising percentage of malignancy compared to TIRADS 4 without calcification group. Also, presence of macrocalcification should not prevent clinicians from making further assessments in case of nondiagnostic results to exclude their association with rather than their causal relation with thyroid malignancies.

The American College of Radiology contrast-enhanced ultrasound Liver Imaging Reporting and Data System and its modified version in diagnosing hepatocellular carcinoma via Sonazoid: a meta-analysis.

The American College of Radiology (ACR) developed the contrast-enhanced ultrasound (CEUS) Liver Imaging Reporting and Data System (LI-RADS) for pure blood contrast agents, but Sonazoid was not included. Modifications to LI-RADS have been proposed for Sonazoid. The purpose of this meta-analysis was to identify and compare the diagnostic efficacy of the two LI-RADS algorithms of Sonazoid. We searched the PubMed, MEDLINE, Web of Science, Embase, and Cochrane Library databases from databases inception to August 31, 2023, to find original studies on the ACR LI-RADS and/or modified LI-RADS algorithm with Sonazoid used as the contrast agent in patients with high-risk hepatocellular carcinoma (HCC). A bivariate random-effects model was used. Data pooling, meta-regression, and sensitivity analysis were performed for meta-analysis. The Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool was used to assess the methodological quality, and the Deeks funnel plot asymmetry test was used to evaluate the publication bias. A meta-analysis of 10 studies with 1,611 observations was conducted. The pooled data for ACR LI-RADS category 5 (LR-5) and modified LR-5 were respectively as follows: pooled sensitivity, 0.70 [95% confidence interval (CI): 0.64-0.75] and 0.81 (95% CI: 0.76-0.86) (P<0.05); pooled specificity, 0.90 (95% CI: 0.82-0.94) and 0.87 (95% CI: 0.81-0.91) (P>0.05); and pooled area under the summary receiver operating characteristic curve, 0.84 and 0.91. The diagnostic performance of LI-RADS category M (LR-M) of the two algorithms was comparable. Study heterogeneity was observed. The results indicated that modified LR-5 algorithm demonstrated improved diagnostic sensitivity compared with the ACR LR-5 algorithm of Sonazoid, with differences observed between the different versions. Further research is needed to validate and explore the optimal diagnostic criteria for HCC using Sonazoid. Before the database search was conducted, this study was registered on PROSPERO (International Prospective Register of Systematic Reviews; CRD42023455220).

Individual Ultrasonographic Characteristics of Thyroid Nodules and Their Cytopathological Correlation to Determine Malignancy Risk.

Background Ultrasonographic evaluation of thyroid nodules is challenging due to their high frequency and low malignancy rate. The risk stratification system developed by the American College of Radiology (ACR) Thyroid Imaging Reporting and Data System (TI-RADS) focuses on addressing the primary contemporary objectives for these lesions, aiming to decrease unnecessary biopsies while maintaining a similar specificity compared with other risk stratification systems. Generally, when indicative of malignancy by ultrasound findings, the next best step in management is an evaluation by fine needle aspiration biopsy (FNAB) and cytological analysis with The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) resultsthat determine further evaluation requirements, actions that are based on the risk of malignancy (ROM) of the assigned category, which could include surgical intervention. Objectives To validate and analyze the individual impact of each ultrasonographic finding indicative of malignancy in the ACR TI-RADS guidelines based on their respective correlation with results obtained by TBSRTC. Materials and method Reports for 212 thyroid ultrasound-guided FNABs from 2018 to 2020 were assessed. Only 117 had both ACR TI-RADS and TBSRTC reports available and were analyzed. Nodules were divided into two groups: ROM < 5% (Bethesda 1, 2; n = 58), and ROM > 5% (Bethesda 3, 4, 5, 6; n = 59).Statistical analysis was performed using the x2 test and bivariate logistic regression model for each characteristic included in ACR TI-RADS. Results Individual ultrasound characteristics with a more pronounced distribution towards the Bethesda > 5% malignancy group were: solid or almost completely solid composition (n=53, 62.3%), very hypoechoic echogenicity (n=3, 75%), wider-than-tall shape (n=50, 50.5%), lobulated or irregular margin (n=23, 65.7%), punctate echogenic foci (n=18, 72%), and thyroid isthmus location (n=6, 75%). Statistically significant individual ultrasonographic characteristics indicative of malignancy included solid or almost completely solid (p = 0.005), very hypoechoic echogenicity (p = 0.046), margin lobulated or irregular (p = 0.031), and punctate echogenic foci (p = 0.015). No significant association was found in the taller-than-wide shape for differentiating malignant from benign lesions (p = 0.969). Conclusions Specific ultrasound characteristics identified in the ACR TI-RADS system demonstrate a stronger correlation with an increased risk of malignancy when compared with cytologic evaluation results. These characteristics include a solid composition, lobulated or irregular margins, punctate echogenic foci, and very hypoechoic echogenicity. Our findings revealedthat the scale points for the taller-than-wide characteristic do not adequately represent its true influence on the risk of malignancy.

Mammographic density in relationships with relevant contributing factors: a multicentric study from Riyadh, Saudi Arabia.

Mammographic breast density (MBD), a well-established factor linked to breast cancer, is the focus of this preliminary report among women across multiple centers in Riyadh. The study aims to identify risk factors associated with high breast density. MBD was assessed at three hospitals in Riyadh, Saudi Arabia, using the American College of Radiology (ACR) categories: A (almost entirely fatty), B (scattered areas of fibroglandular density), C (heterogeneously dense), and D (extremely dense). Breast density distributions were analyzed in relation to age, body mass index (BMI), family history, parity, and hormonal therapy usage. The study included 1,530 women, revealing an inverse association between dense breast proportion and age/BMI. Notably, 43.3% [95% confidence interval (CI): 43.2% to 43.5%] of women aged 40-79 years exhibited heterogeneously or highly dense breasts, with this proportion inversely correlated with age and BMI. Healthcare providers should consider breast density for appropriate screening and, if necessary, recommend supplemental methods. Policymakers and healthcare providers, when discussing breast density notification legislation, should be mindful of its high prevalence, ensuring women notified have opportunities to evaluate breast cancer risk and pursue supplemental screening options if deemed appropriate.

Imaging features and management of focal liver lesions

Notably, the number of incidentally detected focal liver lesions (FLLs) has increased dramatically in recent years due to the increased use of radiological imaging. The diagnosis of FLLs can be made through a well-documented medical history, physical examination, laboratory tests, and appropriate imaging methods. Although benign FLLs are more common than malignant ones in adults, even in patients with primary malignancy, accurate diagnosis of incidental FLLs is of utmost clinical significance. In clinical practice, FLLs are frequently evaluated non-invasively using ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI). Although US is a cost-effective and widely used imaging method, its diagnostic specificity and sensitivity for FLL characterization are limited. FLLs are primarily characterized by obtaining enhancement patterns through dynamic contrast-enhanced CT and MRI. MRI is a problem-solving method with high specificity and sensitivity, commonly used for the evaluation of FLLs that cannot be characterized by US or CT. Recent technical advancements in MRI, along with the use of hepatobiliary-specific MRI contrast agents, have significantly improved the success of FLL characterization and reduced unnecessary biopsies. The American College of Radiology (ACR) appropriateness criteria are evidence-based recommendations intended to assist clinicians in selecting the optimal imaging or treatment option for their patients. ACR Appropriateness Criteria Liver Lesion-Initial Characterization guideline provides recommendations for the imaging methods that should be used for the characterization of incidentally detected FLLs in various clinical scenarios. The American College of Gastroenterology (ACG) Clinical Guideline offers evidence-based recommendations for both the diagnosis and management of FLL. American Association for the Study of Liver Diseases (AASLD) Practice Guidance provides an approach to the diagnosis and management of patients with hepatocellular carcinoma. In this article, FLLs are reviewed with a comprehensive analysis of ACR Appropriateness Criteria, ACG Clinical Guideline, AASLD Practice Guidance, and current medical literature from peer-reviewed journals. The article includes a discussion of imaging methods used for the assessment of FLL, current recommended imaging techniques, innovations in liver imaging, contrast agents, imaging features of common nonmetastatic benign and malignant FLL, as well as current management recommendations.

Evaluation of the Contrast-Enhanced Ultrasound Nonradiation Treatment Response Assessment LI-RADS v2024 Using Data From a Multi-Center Transarterial Chemoembolization Study

Rationale and ObjectiveHepatocellular carcinoma (HCC) locoregional treatment response is commonly evaluated using the Modified Response Evaluation Criteria in Solid Tumors and the American College of Radiology (ACR) Liver Reporting and Data System (LI-RADS) Treatment Response Assessment (TRA) for MRI/CT. This study aims to evaluate the diagnostic performance of the new ACR contrast-enhanced ultrasound (CEUS) Nonradiation TRA LI-RADS v2024 in HCC treated with transarterial chemoembolization (TACE). Methods and MaterialThis retrospective observational study included 87 patients treated with TACE from a previously reported cohort. At 15- and 30-days post-treatment, 68 and 72 HCC lesions were evaluated. Three blinded radiologists with different levels of CEUS experience interpreted the images independently. According to CEUS Nonradiation TRA LI-RADSv2024, both intralesional and perilesional tumor viability were evaluated and final TRA categories were as follows: TR-Nonviable, TR-Equivocal, and TR-Viable. Reference standard used was a composite of histology and imaging. Results140 HCC lesions were analyzed. At 15 days post-treatment, the sensitivity (SN), specificity (SP), positive predictive value (PPV), negative predictive value (NPV), and accuracy of TR-Viable classification ranged from 72.5-94.3%, 72.2-86.4%, 86.8-91.4%, 65.6-86.7%, 76.9-86.8%, respectively. At 30 days post-treatment, the SN, PPV, and NPV of TR-Viable classification decreased, ranging from 65.9-84.2%, 85.7-90.6%, and 59.5-73.9%, respectively, while the SP increased, ranging from 80.0-88.0%. Kappa values ranged from 0.557-0.730, indicating moderate to substantial agreement. ConclusionCEUS Nonradiation TRA LI-RADS is a reliable tool for the detection of viable tumors in lesions treated with TACE and demonstrates reproducibility across readers.

Screening for Breast Cancer: A Comparative Review of Guidelines.

Breast cancer is the most common malignancy diagnosed in the female population worldwide and the leading cause of death among perimenopausal women. Screening is essential, since earlier detection in combination with improvements in breast cancer treatment can reduce the associated mortality. The aim of this study was to review and compare the recommendations from published guidelines on breast cancer screening. A total of 14 guidelines on breast cancer screening issued between 2014 and 2022 were identified. A descriptive review of relevant guidelines by the World Health Organization (WHO), the U.S. Preventive Services Task Force (USPSTF), the American Cancer Society (ACS), the National Comprehensive Cancer Network (NCCN), the American College of Obstetricians and Gynecologists (ACOG), the American Society of Breast Surgeons (ASBrS), the American College of Radiology (ACR), the Task Force on Preventive Health Care (CTFPHC), the European Commission Initiative on Breast Cancer (ECIBC), the European Society for Medical Oncology (ESMO), the Royal Australian College of General Practitioners (RACGP) and the Japanese Journal of Clinical Oncology (JJCO) for women both at average and high-risk was carried out. There is a consensus among all the reviewed guidelines that mammography is the gold standard screening modality for average-risk women. For this risk group, most of the guidelines suggest annual or biennial mammographic screening at 40-74 years, while screening should particularly focus at 50-69 years. Most of the guidelines suggest that the age limit to stop screening should be determined based on the women's health status and life expectancy. For women at high-risk, most guidelines recommend the use of annual mammography or magnetic resonance imaging, while the starting age should be earlier than the average-risk group, depending on the risk factor. There is discrepancy among the recommendations regarding the age at onset of screening in the various high-risk categories. The development of consistent international practice protocols for the most appropriate breast cancer screening programs seems of major importance to reduce mortality rates and safely guide everyday clinical practice.

The value of ACR, European, Korean, and ATA ultrasound risk stratification systems combined with RAS mutations for detecting thyroid carcinoma in cytologically indeterminate and suspicious for malignancy thyroid nodules.

The aim of this study was to evaluate the diagnostic value of four commonly utilized ultrasound (US) RSSs, namely, the American College of Radiology [ACR], European [EU], Korean [K] TI-RADSs and American Thyroid Association [ATA] US-based RSS criteria, in combination with activating point mutations of the RAS genes (NRAS, HRAS, and KRAS) for detection of thyroid carcinoma in cytologically indeterminate and suspicious for malignancy thyroid nodules. We retrospectively analyzed cytologically indeterminate and suspicious for malignancy thyroid nodules which underwent US, molecular testing and surgery between September 1, 2018, and December 31, 2023. Receiver operating characteristic (ROC) curves were generated, and the area under the curve (AUC, 95% confidence interval [CI]) was calculated. A total of 100 cytologically indeterminate and 24 suspicious for malignancy thyroid nodules were analyzed. Compared to the four US-based RSSs alone, the diagnostic value of the four US-based RSSs combined with RAS mutations did not significantly improved (cytologically indeterminate, AUC [95% CI] 0.6 [0.5-0.7] and 0.6 [0.5-0.7], respectively, p = 0.70; cytologically suspicious for malignancy, AUC [95% CI] 0.7 [0.5-0.9] and 0.8 [0.6-0.9], respectively, p = 0.23). The diagnostic value of the four main US-based RSSs (ACR, EU, K, and ATA) was not improved in conjunction with the evaluation of RAS mutations for preoperative risk stratification of cytologically indeterminate thyroid nodules. In cytologically indeterminate nodules categorized according to US-based RSSs, isolated RAS positivity does not reliably distinguish between benignity and malignancy.

Evaluating Machine Learning-Based MRI Reconstruction Using Digital Image Quality Phantoms.

Quantitative and objective evaluation tools are essential for assessing the performance of machine learning (ML)-based magnetic resonance imaging (MRI) reconstruction methods. However, the commonly used fidelity metrics, such as mean squared error (MSE), structural similarity (SSIM), and peak signal-to-noise ratio (PSNR), often fail to capture fundamental and clinically relevant MR image quality aspects. To address this, we propose evaluation of ML-based MRI reconstruction using digital image quality phantoms and automated evaluation methods. Our phantoms are based upon the American College of Radiology (ACR) large physical phantom but created in k-space to simulate their MR images, and they can vary in object size, signal-to-noise ratio, resolution, and image contrast. Our evaluation pipeline incorporates evaluation metrics of geometric accuracy, intensity uniformity, percentage ghosting, sharpness, signal-to-noise ratio, resolution, and low-contrast detectability. We demonstrate the utility of our proposed pipeline by assessing an example ML-based reconstruction model across various training and testing scenarios. The performance results indicate that training data acquired with a lower undersampling factor and coils of larger anatomical coverage yield a better performing model. The comprehensive and standardized pipeline introduced in this study can help to facilitate a better understanding of the performance and guide future development and advancement of ML-based reconstruction algorithms.

Improving LDCT screening rates within a large multidisciplinary community based practice using integrated ACR accredited imaging centers.

e13582 Background: Lung cancer remains the leading cause of cancer-related death in the US, accounting for about 22% of such deaths. Lung cancer detected by low-dose computed tomography (LDCT) screening is discovered at an early stage 64-85% of the time. The benefits of LDCT screening have been demonstrated in numerous trials, but there has been difficulty in establishing programs that screen a high percentage of eligible patients. We present data from the first 18 months of our lung cancer screening program that is designed to provide the highest quality screening, follow-up and access to prevention, diagnosis, and treatment including clinical trials within their local communities. Methods: New York Cancer and Blood Specialists (NYCBS) is a community practice with over 50 locations across NY. While most lung cancer screening programs are hospital-based, NYCBS has a series of American College of Radiology (ACR) accredited imaging centers that perform these screenings and are closely affiliated with oncology, primary care, Ob-Gyn, nephrology, urology and other specialty medical and surgical practices. These centers are strategically located in areas that have high rates of tobacco use as suggested by heat map data from the NY City Community Health Survey . Upon initial patient presentation, all NYCBS and affiliated sites screen patients with tablet-based questionnaires that prompt additional questions during follow-up appointments. Patients with positive findings are discussed during a monthly, system-wide multidisciplinary lung nodule review conference. Follow-up interventions include referrals to pulmonology, interventional radiology, or further imaging with PET/CT. Per ACR guidelines, patients not requiring acute intervention continue with follow-up CT. Results: In 2023, 29,501 patients were screened with an in-office questionnaire. Of those patients, 3,606 were eligible for screening, 225 declined, and 896 (29%) high risk patients proceeded to undergo LDCT screening. In screened patients, 128 underwent follow-up CT, 36 patients had findings requiring immediate intervention, and 6 were diagnosed with lung cancer. 5 of these patients were diagnosed with stage I and 1 patient was diagnosed with stage IV lung cancer. Conclusions: LDCT screening is a proven method to discover early stage lung cancer and improve the survival rate of diagnosed patients but has not been well adopted in practice. With access to a diverse array of multidisciplinary practices across NY and integrated accredited imaging centers, we have increased the accessibility of lung cancer screening and improved transitions to follow-up care. Nationally, only 4.5% of patients at high risk are screened, however, we found that with our approach to patient care, we have achieved among the highest reported screening rates in eligible individuals.

Automatic slice thickness measurement on computed tomography images of American College of Radiology phantom

This study aims to develop an automatic method for calculating slice thickness on an American College of Radiology (ACR) phantom and evaluate its accuracy at variations of orientation angle and slice thickness. The phantom was scanned using Siemens SOMATOM perspective, with variations of the slice thickness (i.e. 1.5, 3, 5, 6, 7, and 10 mm) and rotation angles (i.e. 0.0, 22.5, 45.0, and 67.5°). The phantom rotation was based on the bone object as a reference. After determining the rotation angle, the phantom image was rotated by the angle. Next, profiles of pixel values across the wire objects for measuring slice thickness were developed from rotated phantom images. The slice thickness was measured automatically from the obtained profiles. The results of the automated method are 2.5, 4.1, 5.4, 5.8, 7.8, and 9.8 mm for all varied slice thicknesses. The differences between the automatic and manual methods are within 0.3 mm. The automatic method is capable of detecting slice thickness for various angles. The differences in slice thickness for various angles are within 0.1 mm for a slice thickness of 3 mm. These results are similar when compared to manual measurements. An algorithm for automated slice thickness measurement on ACR phantom has been successfully developed.

Large language foundation models encode clinical radiation oncology domain knowledge: Performance on the American College of Radiology Standardized Examination.

e13585 Background: The integration of Large Language Models (LLMs) into healthcare and medical education will represent a significant paradigm shift, offering transformative potential in how medical knowledge is accessed and assimilated. These models, however, have not yet been systematically trained, tested, or validated on complex medical information such as sub-specialty medical examinations. This study explores the performance of seven major LLMs in clinical radiation oncology using residency in-training exams. Methods: In this study, the 2021 American College of Radiology (ACR) Radiation Oncology In-Training Exam (TXIT) was used to evaluate the performance of various LLMs, including OpenAI's GPT-3.5-turbo, GPT-4, GPT-4-turbo, three Meta's Llama-2 models (7 billion, 13 billion, and 70 billion parameter), and Google's PaLM-2-text-bison. The ACR provided the publicly available national scoring for this exam. The exam comprised 298 questions across 13 domains, including clinical radiation oncology (195 questions, 65.4%). The exam was processed through each LLM via an application programming interface. LLM-generated answers were analyzed by clinical disease sites and compared to Radiation Oncology trainee performance and stratified by Post-Graduate Year (PGY) 2-5. Results: LLMs showed varied performance in the overall clinical radiation oncology domain, with OpenAI's GPT-4-turbo having the best performance with 68.0% correct answers, GPT-4 61.0%, GPT-3.5-turbo 48.0%, PaLM-2-text-bison 40.0%, and then the three Llama-2 models (70b 37.0%, 13b 38%, 7b 26%). GPT-4-turbo performed superiorly to lower-level (PGY2 51.6%, PGY3 61.6%) and comparably to upper-level radiation oncology trainees (PGY4 64.1%, PGY5 68.3%). Notably, GPT-4-turbo demonstrated 7.0% improvement over its predecessor GPT-4. LLMs scored the lowest in the gastrointestinal, genitourinary, and gynecology domains and highest in the bone and soft tissue, central nervous system and eye, and head, neck, and skin domains. Conclusions: GPT-4-turbo demonstrates clinical accuracy comparable to upper-level and superior to lower-level trainees in nearly all clinical domains. Conversely, Llama2 foundation models demonstrate overall worse performance than Level 1 (PGY2) trainees. Score discrepancies across disease site domains may be due to data availability, complexity of medical conditions, quality and quantity of training datasets, and interdisciplinary data inputs. Future research will need to evaluate the performance of models that are fine-tune trained in clinical oncology. This study also underscores the need for rigorous validation of LLM-generated information against established medical literature and expert consensus, necessitating expert oversight in their application in medical education and practice.

The machine learning-based model for lateral lymph node metastasis of thyroid medullary carcinoma improved the prediction ability of occult metastasis.

For medullary thyroid carcinoma (MTC) with no positive findings in the lateral neck before surgery, whether prophylactic lateral neck dissection (LND) is needed remains controversial. A better way to predict occult metastasis in the lateral neck is needed. From January 2010 to January 2022, patients who were diagnosed with MTC and underwent primary surgery at our hospital were retrospectively reviewed. We collected the patients' baseline characteristics, surgical procedure, and rescored the ultrasound images of the primary lesions using American College of Radiology (ACR) Thyroid Imaging, Reporting and Data System (TI-RADS). Regularized logistic regression, 5-fold cross-validation and decision curve analysis was applied for lateral lymph node metastasis (LLNM) model's development and validation. Then, we tested the predictive ability of the LLNM model for occult LLNM in cN0-1a patients. A total of 218 patients were enrolled. Five baseline characteristics and two TI-RADS features were identified as high-risk factors for LLNM: gender, baseline calcitonin (Ctn), tumor size, multifocality, and central lymph node (CLN) status, as well as TI-RADS margin and level. A LLNM model was developed and showed a good discrimination with 5-fold cross-validation mean area under curve (AUC) = 0.92 ± 0.03 in the test dataset. Among cN0-1a patients, our LLNM model achieved an AUC of 0.91 (95% CI, 0.88-0.94) for predicting occult LLNM, which was significantly higher than the AUCs of baseline Ctn (0.83) and CLN status (0.64). We developed a LLNM prediction model for MTC using machine learning based on clinical baseline characteristics and TI-RADS. Our model can predict occult LLNM for cN0-1a patients more accurately, then benefit the decision of prophylactic LND.

A survey on mean glandular dose in mammography examination and the factors affecting it in Shahid Sadoughi Hospital, Yazd, Iran.

mammography is the gold standard in the early detection of breast cancer. Due to the increase in the rate of women suffering from this malignancy all over the world, this imaging modality has been widely used. Considering the side effects caused by ionizing radiation to measure the carcinogenic risk of mammography X-rays, mean glandular dose (MGD) is the best parameter to evaluate the dose received by patients undergoing mammography. The aims of this study were to measure MGD in mammography in mammographic craniocaudal (CC) and mediolateral oblique (MLO) projections and investigate the relationship of MGD with compressed breast thickness (CBT), body mass index, age of the patient, and device exposure conditions. this cross-sectional analytical study was conducted on women aged 30-70 referring to the mammography unit of Shahid Sadoughi Hospital in Yazd city from May to August 2022. The TLD-GR 200 (thermoluminescence dosimeter) was placed on the breast of the patients for CC and MLO projections, and then the MGD was obtained by multiplying the entrance surface dose and the normalized glandular dose. Analysis of data (such as demographic information of patients, CBT, kVp, and mAs) was done by SPSS 23 software. The normality of the data was checked using Shapiro-Wilk tests. It was found that except for age, other variables did not have a normal distribution; therefore, equivalent parametric and nonparametric tests were used. In this regard, Spearman's correlation was used to assess the correlation between variables. P-value < .05 was considered as level of significance. The mean±standard deviation (SD) age of patients was 47.3±7.1years. The median±IQR (the interquartile range (IQR) is a measure of statistical dispersion, which is the spread of the data. It is defined as the difference between the 75th and 25th percentiles of the data.) (mean±SD) value of MGD per woman was 1.2±0.4mGy (1.3±0.3mGy). The median±IQR MGD in the MLO and CC projections was 1.6±0.6mGy and 0.9±0.4mGy, respectively. Significant relationships (P-value ≤ .001) were observed between MGD with CBT (R=0.62) and age (R=-0.85). The results showed that the mammography unit at Shahid Sadoughi Hospital in Yazd is functioning properly. The calculated median±IQR MGD per woman referring to this unit (1.2±0.4mGy) was clearly below the dose limit recommended by American College of Radiology and International Commission on Radiological Protection (3mGy). Moreover, among the factors affecting MGD, the highest correlation was seen between MGD and age (R=-0.85).

Understanding Washington State’s Low Uptake of Lung Cancer Screening in Two Steps: A Geospatial Analysis of Patient Travel Time and Health Care Availability of Imaging Sites

BackgroundEarly detection of lung cancer reduces cancer mortality; yet uptake for lung cancer screening (LCS) has been limited in Washington State. Geographic disparities contribute to low uptake, but do not wholly explain gaps in access for underserved populations. Other factors, such as an adequate workforce to meet population demand and the capacity of accredited screening facility sites must also be considered. Research QuestionWhat proportion of the eligible population for LCS have access to LCS facilities in Washington State? Study Design and MethodsWe used the enhanced two-step floating catchment (E2SFCA) model to evaluate how geographic accessibility in addition to availability of LCS imaging centers contribute to disparities. We used available data on radiologic technologist volume at each American College of Radiology (ACR) accredited screening facility site to estimate each site’s capacity to meet potential population demand. Spearman rank correlation coefficients of the spatial access ratios (SPARs) were compared with the 2010 Rural-Urban Commuting Area (RUCA) codes and Area Deprivation Index (ADI) quintiles to identify characteristics of populations at risk for lung cancer with greater and lesser levels of access. ResultsA total of 549 radiologic technologists were identified across the 95 ACR accredited screening facilities. We observed that 95% of the eligible population had proximate geographic access to any ACR facility. However, when we incorporated the E2SFCA method, we found significant variation of access for eligible populations. The inclusion of the availability measure attenuated access for most of the eligible population. Furthermore, we observed that rural areas were substantially correlated and areas with greater socioeconomic disadvantage were modestly correlated with lower access. InterpretationRural and socioeconomically disadvantaged areas face significant disparities. The E2SFCA models demonstrated that capacity is an important component and how geographic access and availability jointly contribute to disparities in access to LCS.

Safe Use of Contrast Media in Radiology (Clinical Guidelines)

In recent years, the frequency of contrast-enhanced radiological studies has increased significantly, and the issues of their selection and rational use do not lose their relevance. These methodological recommendations represent a complete up-to-date guide for using contrast agents (CA) in radiology. Types of currently used CA in computed tomography, magnetic resonance imaging, and ultrasound examinations are described. Safety rules for injection of each CA type are systematized, the principles of dosing and possible side effects are explained. In addition, it is important to highlight the issues of interactions between CA and other drugs that patient might take, in particular, the possible deterioration of renal function when using CA in diabetes mellitus patients taking metformin. It should be noted that these recommendations have undergone significant changes in recent years. Also questionnaire templates for patients prior to the contrast-enhanced study are given in the supplements. The methodological guidelines are based on current publications of international experts on CA use in radiology as well as on the data of two major guidelines: American College of Radiologists (ACR) Guidelines (2023) and European Society of Urogenital Radiology (ESUR) Safety Recommendations (2018, version 10). Thus, the information presented is validated, which provides grounds for its application in real clinical practice. The guidelines will be actualized as new scientific evidence becomes available, but to date they appear to be the most relevant.

#3089 Radiological assessment of suspected acute pyelonephritis in the management of urosepsis and prevention of acute kidney injury

Abstract Background and Aims Sepsis, a serious complication of infection, may result in organ dysfunction and is responsible for almost 20% of global deaths. Identification of acute pyelonephritis (pyelo), requires early clinical assessment, diagnostics and antimicrobial therapy to prevent septic shock and potential death. In 2022, the American College of Radiology (ACR) published a revised appropriateness criteria for radiological imaging in suspected acute pyelo (1). Five variant [V] categories were defined according to presence of pregnancy, stone disease, renal transplantation, complicated (i.e. recurrent pyelo, DM, immunosuppression) and uncomplicated (first) presentation. The aim of this project was to establish the proportion of patients with suspected acute pyelonephritis undergoing radiological assessment, the selected modality and radiological findings, which could contribute to the diagnosis and management. Method This observational retrospective study of 55 cases with suspected acute pyelo over 6 months. Patients who were decanted to nephrology specialist care from the acute medical take were assessed. Patients were grouped into 5 categories [Variant 1-5] as per appropriateness criteria of the ACR (Table 1a). Patient demographics, renal function and signs of sepsis were recorded. The proportion undergoing radiological assessment, the modality and outcomes are outlined in Table 1. Results Demographically, 66% of patients were female, the median age was 49 years [IQR 30] and 93.6% were Caucasian. Pre-admission baseline Creatinine (Cr) was 75 µmol/l [IQR 75]. Admission Cr was 85 µmol/l [IQR 74}, with peak inpatient Cr 94 µmol/l. Sepsis parameters (hypotensive/ tachycardia/ high CRP) on admission were observed in 38% of patients. Modality Choice 92.7% of study participants received imaging over the course of their inpatient stay. The primary modality of choice was CTKUB (36.4%), with 25.5% of patients receiving targeted ultrasound. In the setting of uncomplicated acute pyelo (V1), CTKUB was the most common diagnostic modality. Patients with a history of renal calculi (V3) were imaged equally with CTKUB and targeted ultrasound (42.9% CTKUB vs. 42.9% USS). Patients with a history of renal transplant with a native kidney in-situ were most commonly investigated with targeted ultrasound to assess for acute pyelo 92.3%. Imaging Results 52.7% of imaging had positive findings. Most frequently recorded was pyelo (23.6%), renal/ureteric calculi (16.4%) and hydronephrosis (12.7%). In presumed uncomplicated acute pyelo (Variant 1), 29% of patients had radiological evidence of pyelo. 22.2% had newly diagnosed renal/ ureteric calculus. 11.1% had hydronephrosis. One patient had both stones and hydronephrosis. In known stone disease, two presented with hydronephrosis [V3]. Two transplant cases had hydronephrosis [V5]. Conclusion Early detection of pyelonephritis and its underlying aetiology is imperative in the management of urosepsis. Results suggest 22.2% had newly diagnosed renal/ ureteric calculus in those not known to have renal disease [V1]. In total 12% had hydronephrosis, and nearly a quarter had pyelo visible on imaging. No abscesses were observed which guided duration of antibiotic therapy. Early intervention including anti-microbial therapy and management of acute kidney injury were guided by imaging outcomes. Access to specialist services and early imaging is crucial in successful outcomes in urosepsis.

Preoperative Clinical and Ultrasonographic Predictors for Aggressive Behaviors in Sporadic Medullary Thyroid Carcinomas.

Objective: To explore the clinical and ultrasonographic predictors for aggressive behaviors preoperatively in sporadic medullary thyroid carcinomas (MTCs). Materials and Methods: The preoperative clinical and ultrasonographic characteristics of patients diagnosed with MTCs between January 2009 and May 2022 were retrospectively reviewed. MTCs were described and categorized according to the American College of Radiology (ACR) thyroid imaging reporting and data system classification by 2 radiologists. Interobserver agreement was evaluated by kappa test. Univariate and multivariate analyses were performed to identify predictors of aggressive behaviors in MTCs. The log-rank test was utilized to compare differences in Kaplan-Meier (K-M) curves for postoperative disease-free survival (PDFS). Results: A total of 120 patients were enrolled in the final study. Male sex was significant risk factor for metastasis, perithyroidal invasion, and lateral cervical lymph node (LCLN) metastasis [odds ratio (OR): 3.109, P = .019; OR: 5.316, P = .018; OR: 5.154 P = .012, respectively]. The kappa values for all ultrasonic characteristics were high (ranged from 0.811 to 0.941). Size, focality, and margin of the nodule were independent risk factors for metastasis, as well as for LCLN metastasis. Whereas margin (P < .001) and a subcapsular location (P = .021) were risk factors for perithyroidal invasion. According to K-M analysis, PDFS of patients differed significantly between groups with/without metastasis (P < .001), groups with/without perithyroidal extension (P < .001) and groups with/without LCLN metastasis (P < .001). Conclusions: Male sex is an independent risk factor for metastasis, perithyroidal invasion, and LCLN metastasis. The large size (≥2.55 cm for metastasis, ≥2.15 cm for LCLN metastasis, respectively), multifocality, and irregular margin of nodules were independent risk factors for both metastasis and LCLN metastasis. Extrathyroidal extension and a subcapsular location were risk factors for perithyroidal invasion. Moreover, patients with metastasis/perithyroidal extension/LCLN metastasis exhibited worse PDFS.

Fair evaluation of federated learning algorithms for automated breast density classification: The results of the 2022 ACR-NCI-NVIDIA federated learning challenge

The correct interpretation of breast density is important in the assessment of breast cancer risk. AI has been shown capable of accurately predicting breast density, however, due to the differences in imaging characteristics across mammography systems, models built using data from one system do not generalize well to other systems. Though federated learning (FL) has emerged as a way to improve the generalizability of AI without the need to share data, the best way to preserve features from all training data during FL is an active area of research. To explore FL methodology, the breast density classification FL challenge was hosted in partnership with the American College of Radiology, Harvard Medical Schools’ Mass General Brigham, University of Colorado, NVIDIA, and the National Institutes of Health National Cancer Institute. Challenge participants were able to submit docker containers capable of implementing FL on three simulated medical facilities, each containing a unique large mammography dataset. The breast density FL challenge ran from June 15 to September 5, 2022, attracting seven finalists from around the world. The winning FL submission reached a linear kappa score of 0.653 on the challenge test data and 0.413 on an external testing dataset, scoring comparably to a model trained on the same data in a central location.