Role of US LI-RADS in the LI-RADS Algorithm.

The US Liver Imaging Reporting and Data System (LI-RADS) was released in 2017 and is the newest of the four American College of Radiology (ACR) LI-RADS algorithms. US LI-RADS provides standardized terminology, technical recommendations, and a reporting framework for US examinations performed for screening or surveillance in patients at risk for developing hepatocellular carcinoma (HCC). The appropriate patient population for screening and surveillance includes individuals who are at risk for developing HCC but do not have known or suspected cancer. This includes patients with cirrhosis from any cause and subsets of patients with chronic hepatitis B virus infection in the absence of cirrhosis. In an HCC screening or surveillance study, US LI-RADS recommends assigning two scores that apply to the entire study: the US category, which determines follow-up, and a visualization score, which communicates the expected level of sensitivity of the examination but does not affect management. Three US categories are possible: US-1 negative, a study with no evidence of HCC; US-2 subthreshold, a study in which an observation less than 10 mm is depicted that is not definitely benign; and US-3 positive, a study in which an observation greater than or equal to 10 mm or a new thrombus in vein is identified, for which diagnostic contrast material-enhanced imaging is recommended. Three visualization scores are possible: A (no or minimal limitations), B (moderate limitations), and C (severe limitations). ©RSNA, 2019.

Hepatic steatosis: Qualitative and quantitative sonographic assessment in comparison to histology.

Introduction: Globally, B-mode ultrasound is the most common modality used for the diagnosis of hepatic steatosis. We aimed to assess the correlation between qualitative liver ultrasound parameters, attenuation imaging (ATI) and histopathology-diagnosed steatosis grade obtained from liver biopsy. Our secondary aim was to examine the interobserver variability of qualitative ultrasound features. Methods: A retrospective cohort study was performed which included adult patients (age ≥ 18 years) who had same-day liver ultrasound, ATI and liver biopsy for grading hepatic steatosis severity between 2018 and 2022. The qualitative US features for hepatic steatosis were independently scored by three radiologists and interobserver variability was examined. Histologic steatosis grade, ATI and qualitative ultrasound parameters were compared. Results: Ninety patients were included; 67% female with a median age of 54 (IQR 39-65) years. The radiologist's overall impression had the highest correlation (very strongly correlated) with histologic steatosis grade (r = 0.82, P < 0.001). ATI coefficient and all qualitative ultrasound B-mode features except for liver echotexture and focal fat sparing were strongly correlated with histologic steatosis grade (r ≥ 0.70, P < 0.001). Most qualitative ultrasound features had good agreement between observers (Kappa statistic 0.61-1.0, P < 0.001), (Kendall coefficient 0.92, P < 0.001). Conclusion: The examined qualitative ultrasound parameters and ATI had good-excellent performance for diagnosing clinically significant hepatic steatosis; however, the radiologist's overall impression had the best correlation with histologic steatosis grade. Our findings suggest an ongoing role for qualitative liver ultrasound assessment of hepatic steatosis despite the emergence of newer quantitative measures.

The Great Contrast Shortage of 2022-Lessons learnt in Australia.

INTRODUCTION: Computed tomography (CT) imaging is one of the most commonly used diagnostic tools. Iodine-based contrast media (IBCM) are frequently administered intravenously to improve soft tissue contrast in a wide range of CT scans. Supply chain disruptions triggered by the SARS-CoV-19 pandemic led to a global shortage of IBCM in mid-2022. The purpose of this study was to explore the impact of this shortage on the delivery of healthcare in Western Australia. METHODS: We performed a single-centre retrospective analysis of the provision of CT studies, comparing historical patterns to the shortage period. We focussed our attention on the total number of CT scans (noncontrast CT [NCCT] and contrast-enhanced CT [CECT]) and also specifically CT pulmonary angiogram (CTPA) and CT neck angiogram with or without inclusion of circle of Willis (CTNA) examinations. We also examined whether a decrease was compensated by increasing frequency of alternate examinations such as ventilation/perfusion (V/Q) scans, carotid Doppler ultrasound studies and Magnetic Resonance Angiograms (MRAs). RESULTS: Since 2012, there has been an approximate linear increase in the frequency of CT examinations. During the period of contrast shortage, there was an abrupt drop-off by approximately 50% in the CECT, CTPA and CTNA groups compared with the preceding 6 weeks (49%, 55% and 44%, respectively, with P < 0.001 in all cases). During the contrast shortage, the frequency of V/Q scans increased fivefold (from 13 to 65; P < 0.001). However, the provision of carotid Doppler ultrasound studies and MRAs remained approximately stable in frequency across recent time intervals. CONCLUSION: Our findings demonstrate that the IBCM shortage crisis had a very significant impact on the delivery of healthcare. While V/Q scans could (partially) substitute for CTPA studies in suspected pulmonary emboli, there appeared to be no valid alternative for CTNA studies in stroke calls. The unexpected and critical shortage of IBCM forced healthcare professionals to conserve resources, prioritise indications, triage patients based on risk, explore alternate imaging strategies and prepare for similar events recurring in the future.

Monitoring quality of care in hepatocellular carcinoma: A modified Delphi consensus.

Although there are several established international guidelines on the management of hepatocellular carcinoma (HCC), there is limited information detailing specific indicators of good quality care. The aim of this study was to develop a core set of quality indicators (QIs) to underpin the management of HCC. We undertook a modified, two-round, Delphi consensus study comprising a working group and experts involved in the management of HCC as well as consumer representatives. QIs were derived from an extensive review of the literature. The role of the participants was to identify the most important and measurable QIs for inclusion in an HCC clinical quality registry. From an initial 94 QIs, 40 were proposed to the participants. Of these, 23 QIs ultimately met the inclusion criteria and were included in the final set. This included (a) nine related to the initial diagnosis and staging, including timing to diagnosis, required baseline clinical and laboratory assessments, prior surveillance for HCC, diagnostic imaging and pathology, tumor staging, and multidisciplinary care; (b) thirteen related to treatment and management, including role of antiviral therapy, timing to treatment, localized ablation and locoregional therapy, surgery, transplantation, systemic therapy, method of response assessment, and supportive care; and (c) one outcome assessment related to surgical mortality. Conclusion: We identified a core set of nationally agreed measurable QIs for the diagnosis, staging, and management of HCC. The adherence to these best practice QIs may lead to system-level improvement in quality of care and, ultimately, improvement in patient outcomes, including survival.

Ultrasound Evaluation in Patients at Risk for Hepatocellular Carcinoma.

In the context of chronic liver disease (CLD), sonographic features of hepatic steatosis, cirrhosis, and portal hypertension are discussed and examples are provided. The impact of CLD and hepatocellular carcinoma (HCC) is introduced, providing the rationale for a robust HCC screening and surveillance program for at-risk patients. The American College of Radiology Liver Imaging Reporting and Data System algorithms for screening and surveillance by ultrasound and for the definitive diagnosis of HCC by contrast-enhanced ultrasound are explained, with imaging examples provided. Contrast-enhanced ultrasound technique, limitations, and pitfalls also are introduced.

Alternatives to the baseline KUB for CTKUB-detected calculi: evaluation of CT scout and average and maximum intensity projection images.

PURPOSE: A CT of the kidneys, ureters, and bladder (CTKUB) is the investigation of choice in suspected renal colic. Plain kidney, ureter, and bladder radiographs (KUB) can be used to monitor the progress of a stone if radiographically visible on a baseline KUB. This study aims to determine if a low-dose CT Scout, thick-slab average intensity projection (AIP), or maximum intensity projection (MIP) images are suitable as substitutes for a baseline KUB. METHOD: A retrospective review of patients from a tertiary adult institute that had a positive CTKUB and a KUB within 4 h of the CT was performed. Two consultant radiologists independently reviewed the KUB, CT Scout, AIP, and MIP for stone visibility and their sensitivities and agreement values were compared. Stone characteristics (size, location, and peak Hounsfield units) and patient thickness were recorded and examined for any association with discordant results. RESULTS: 74 stones were evaluated for the study. KUB had a sensitivity of 66.2% (95% CI 54.3-76.8), CT Scout 47.3% (95% CI 35.6-59.3), AIP 55.4% (95% CI 43.4-67.0), and MIP 83.8% (95% CI 73.4-91.3). Fair agreement was found between the KUB and both CT Scout (κ=0.363, 95% CI 0.167-0.558) and AIP (κ=0.384, 95% CI 0.175-0.592). Moderate agreement was found between the KUB and MIP (κ=0.412, 95% CI 0.198-0.625). Neither any stone characteristic nor patient thickness had a significant association with discordant results. CONCLUSION: None of the possible substitutes for a baseline KUB showed strong agreement with the KUB. Low-dose CT Scouts have a similar sensitivity to the published literature for higher dose CT Scouts.

Sonographic visibility of breast tissue markers: a tissue phantom comparison study.

Rationale and objectives: Several commercially available breast tissue markers are promoted as being sonographically visible, allowing for subsequent targeting using ultrasound. The aim of this study was to compare the visibility of selected sonographic markers with the use of tissue phantoms. Materials and methods: Seven different markers were deployed into chicken and beef tissue phantoms, including a non-sonographically enhanced marker used as a baseline. Six participants assessed their sonographic visibility and needle targeted the markers using ultrasound. The sonographic visibility of each marker was graded, with scores corrected for accuracy following mammographic review of needle targeting position. Results: Only four of the six "ultrasound enhanced" markers demonstrated statistically significant greater visibility than the non-sonographically designed marker (P range < 0.001 to 0.04). Marker size (P < 0.001) and composition (P < 0.004) were shown to be contributing factors, with the composition of the BiomarC™ (Carbon Medical Technologies Inc, St Paul, MN, USA) demonstrating the highest conspicuity adjusted for length. Conclusion: There is significant variance in the visibility of breast tissue markers purported to be visible on ultrasound. Marker size, composition and possibly shape are contributory factors, with the utilisation of non-metallic components associated with improved conspicuity. Our study provides a basis for further determination of optimal marker qualities, and we recommend evaluation with a larger sample size and an "in-vivo" technique.

Nipple discharge in a screening programme: imaging findings with pathological correlation.

BreastScreen Australia provides free mammographic screening for asymptomatic women over the age of 40, targeting women aged 50-69. Occasionally women will present to screening programmes with a history of nipple discharge, which is uncommonly associated with significant underlying breast disease. Seventy-six women with a history of nipple discharge were recalled to BreastScreen Western Australia assessment centres from 2004 to 2008, of whom 72 were recalled primarily for their symptoms. Thirty-six of these patients had pathology investigations, including 18 nipple discharge smears, 17 fine needle aspirations, 11 core biopsies and eight surgical biopsies or therapeutic resections. The biopsies found 11 intraduct papillomas and one invasive ductal carcinoma with ductal carcinoma in situ. Fourteen patients had imaging findings consistent with benign mammary duct ectasia. Our findings confirm that the presentation of nipple discharge in a screening programme is uncommonly associated with significant breast disease, and present representative cases of the radiological findings with pathological correlation of benign and malignant causes including mammary duct ectasia, intraduct papillomas, multiple papillomas, invasive ductal carcinoma and ductal carcinoma in situ.