Acquired ductopenia: an insight into imaging findings.

Hepatic ductopenia is a pathologic diagnosis characterized by a decrease in the number of intrahepatic bile ducts as a consequence of various underlying etiologies. Some etiologies, such as primary sclerosing cholangitis, primary biliary cholangitis, and ischemic cholangitis, often have distinctive imaging findings. In contrast, other causes such as chronic rejection following liver transplantation, drug-induced biliary injury, infection, malignancy such as lymphoma, and graft-versus-host disease may only have ancillary or non-specific imaging findings. Thus, diagnosing ductopenia in conditions with nonspecific imaging findings requires a multidimensional approach, including clinical evaluation, serological testing, imaging, and liver histology to identify the underlying cause. These etiologies lead to impaired bile flow, resulting in cholestasis, liver dysfunction, and, ultimately, cirrhosis and liver failure if the underlying cause remains untreated or undetected. In the majority of instances, individuals diagnosed with ductopenia exhibit a positive response to treatment addressing the root cause or cessation of the causative agent. This article focuses on acquired causes of ductopenia, its clinical manifestation, histopathology, imaging diagnosis, and management.

Off the wall: incidental paraspinal and pelvic muscle pathology on abdominopelvic imaging.

As the use of cross-sectional abdominal and pelvic imaging has increased exponentially in the past several decades, incidental musculoskeletal findings have become commonplace. These are often unrelated to the indication for the examination and are frequently referred to as the "radiologist's blind spot" on these studies. The differential diagnosis for abnormalities of the paraspinal and pelvic musculature is, in many cases, quite different from the anterior abdominal wall muscles. Furthermore, due to their relatively deep location, pathology involving the former muscle groups is more likely to be clinically occult, often presenting only incidentally when the patient undergoes cross-sectional imaging. Effective treatment of diseases of these muscles is dependent on adherence to a diverse set of diagnostic and treatment algorithms. The purpose of this review article is to familiarize the radiologist with the unique pathology of these often-overlooked muscles of the abdomen and pelvis.

Contrast-Enhanced Ultrasound for Image-Guided Procedures.

Contrast-enhanced ultrasound (CEUS) uses intravenously injected gas microbubbles as a pure blood pool contrast agent to demonstrate blood flow and tissue perfusion at a much higher sensitivity than color Doppler and power Doppler ultrasound. CEUS has gained traction in abdominal diagnostic imaging for improved lesion detection and characterization and a complementary problem-solving tool to CT and MRI. In addition to its diagnostic applications, CEUS has also proven useful for pre-procedure planning, procedure guidance, and post-procedure evaluation. This review provides a practical overview and guides to the application of CEUS in percutaneous, ultrasound-guided, needle-driven procedures, focusing on 2 common procedures, which illustrate the many benefits of CEUS- core needle biopsy (CNB) and percutaneous hepatic lesion ablation.

Surveillance imaging of type II endoleak with contrast-enhanced ultrasound.

Type II endoleak is the most common type of endoleak after endovascular repair of abdominal aortic aneurysm and has been reported in up to 20-50% of patients. Patients undergo lifelong surveillance of aortic graft stents to monitor for endoleak. Contrast-enhanced ultrasound can be an adjunct to CT angiography (CTA) which is the preferred imaging modality for surveillance. However, CT angiography introduces challenges of recurring cost, exposure to ionizing radiation, and the need for iodinated contrast dye. We report a case using CEUS for the detection of type II endoleak.

The Many Faces of Primary Sclerosing Cholangitis: Controversy Abounds.

Primary sclerosing cholangitis (PSC) is notoriously challenging to manage given its heterogeneity with regard to diagnosis, management, and progression. The lack of disease-modifying therapy and variable rate of onset of cirrhosis, portal hypertension-related decompensating events, jaundice, pruritus, biliary complications, and need for liver transplantation is deeply unsettling to clinicians and patients alike. Recent updated practice guidance by the American Association for the Study of Liver Diseases and the European Association for the Study of the Liver endeavored to highlight some of these challenges. However, these references only briefly address clinical dilemmas that providers face on a daily basis. This review aims to further discuss these controversial topics, including providing insight into the utility of ursodeoxycolic acid, the significance of alkaline phosphatase normalization, when to consider PSC variants and mimickers, and the implications of continuous hepatobiliary malignancy screening. In particular, there has been a growing body of literature raising concern about repeat exposure to gadolinium-containing contrast. Patients with PSC are potentially at risk for large lifetime exposure to gadolinium related to frequent magnetic resonance imaging scans and whether this carries any negative long-term adverse effects remains unknown.

A Novel Thyroid Ultrasound Proficiency Metric Designed Through a Multidisciplinary Delphi Approach.

BACKGROUND: Thyroid ultrasounds extend surgeons' outpatient capabilities and are essential for operative planning. However, most residents are not formally trained in thyroid ultrasound. The purpose of this study was to create a novel thyroid ultrasound proficiency metric through a collaborative Delphi approach. METHODS: Clinical faculty experienced in thyroid ultrasound participated on a Delphi panel to design the thyroid Ultrasound Proficiency Scale (UPS-Thyroid). Participants proposed items under the categories of Positioning, Technique, Image Capture, Measurement, and Interpretation. In subsequent rounds, participants voted to retain, revise, or exclude each item. The process continued until all items had greater than 70% consensus for retention. The UPS-Thyroid was pilot tested across 5 surgery residents with moderate ultrasound experience. Learning curves were assessed with cumulative sum. RESULTS: Three surgeons and 4 radiologists participated on the Delphi panel. Following 3 iterative Delphi rounds, the panel arrived at >70% consensus to retain 14 items without further revisions or additions. The metric included the following items on a 3-point scale for a maximum of 42 points: Positioning (1 item), Technique (4 items), Image Capture (2 items), Measurement (2 items), and Interpretation (5 items). A pilot group of 5 residents was scored against a proficiency threshold of 36 points. Learning curve inflection points were noted at between 4 to 7 repetitions. CONCLUSIONS: A multidisciplinary Delphi approach generated consensus for a thyroid ultrasound proficiency metric (UPS-Thyroid). Among surgery residents with moderate ultrasound experience, basic proficiency at thyroid ultrasound is feasible within 10 repetitions.

Testicular cavernous hemangioma masquerading as testicular malignancy.

Cavernous hemangiomas are benign tumors of vascular origin that can develop in any part of the body. However, its occurrence in the testis is rare. To the best of our knowledge, we are reporting the first case of a patient with cavernous hemangioma with concern for an extracapsular extension on ultrasound imaging.

Radiologic findings of biliary complications post liver transplantation.

Liver transplantation is a potentially curative treatment for patients with acute liver failure, end-stage liver disease, and primary hepatic malignancy. Despite tremendous advancements in surgical techniques and immunosuppressive management, there remains a high rate of post-transplant complications, with one of the main complications being biliary complications. In addition to anastomotic leak and stricture, numerous additional biliary complications are encountered, including ischemic cholangiopathy due to the sole arterial supply of the bile ducts, recurrence of primary biliary disease, infections, biliary obstruction from stones, cast, or hemobilia, and less commonly cystic duct remnant mucocele, vanishing duct syndrome, duct discrepancy and kinking, post-transplant lymphoproliferative disorder, retained stent, and ampullary dysfunction. This article presents an overview of biliary anatomy and surgical techniques in liver transplantation, followed by a detailed review of post-transplant biliary complications with their corresponding imaging findings on multiple modalities with emphasis on magnetic resonance imaging and MR cholangiopancreatography.

Primary sclerosing cholangitis: review for radiologists.

Primary sclerosing cholangitis is a rare chronic inflammatory disease affecting the bile ducts, which can eventually result in bile duct strictures, cholestasis and cirrhosis. Patients are often asymptomatic but may present with clinical features of cholestasis. Imaging plays an important role in the diagnosis and management. This review covers the pathophysiology, clinical features, imaging findings as well as methods of surveillance and post-transplant appearance.

Thyroid anatomy and ultrasound evaluation.

A good understanding of the anatomic structures of the neck surrounding the thyroid gland is a requisite for safely performing image guided procedures on the thyroid gland. Patients presenting for treatment of thyroid nodules can have anatomy that is distorted by the nodules or by prior surgery. This pictorial review describes the anatomy of the thyroid gland and surrounding structures. Additionally, a review of how to perform an ultrasound exam of the thyroid gland and how to categorize thyroid nodules is included.

Inhibition of 11ß-Hydroxysteroid dehydrogenase-1 with AZD4017 in patients with nonalcoholic steatohepatitis or nonalcoholic fatty liver disease: A randomized, double-blind, placebo-controlled, phase II study.

AIM: To evaluate whether short-term treatment with a selective 11ß-Hydroxysteroid dehydrogenase-1 (11ß-HSD1) inhibitor, AZD4017, would block hepatic cortisol production and thereby decrease hepatic fat in patients with nonalcoholic fatty liver disease (NAFLD)/nonalcoholic steatohepatitis (NASH), with or without type 2 diabetes (T2D). MATERIALS AND METHODS: This was a randomized, double-blind, placebo-controlled, phase 2 study conducted at two sites. Key inclusion criteria were the presence of NAFLD or NASH on magnetic resonance imaging (MRI) or recent biopsy positive for NASH. Enrolled patients were randomly assigned (1:1) to AZD4017 or placebo for 12 weeks. Primary outcomes were between-group differences in mean change from baseline to week 12 in liver fat fraction (LFF) and conversion of 13 C cortisone to 13 C cortisol in the liver. RESULTS: A total of 93 patients were randomized; 85 patients completed treatment. The mean (standard deviation [SD]) change in LFF was -0.667 (5.246) and 0.139 (4.323) in the AZD4017 and placebo groups (P = 0.441). For patients with NASH and T2D, the mean (SD) change in LFF was significantly improved in the AZD4017 versus the placebo group (-1.087 [5.374] vs. 1.675 [3.318]; P = 0.033). Conversion of 13 C cortisone to 13 C cortisol was blocked in all patients in the AZD4017 group. There were no significant between-group differences (AZD4017 vs. placebo) in changes in fibrosis, weight, levels of liver enzymes or lipids, or insulin sensitivity. CONCLUSION: Although the study did not meet one of the primary outcomes, AZD4017 blocked the conversion of 13 C cortisone to 13 C cortisol in the liver in all patients who received the drug. In patients with NASH and T2D, AZD4017 improved liver steatosis versus placebo.

Comparison of Thyroid Risk Categorization Systems and Fine-Needle Aspiration Recommendations in a Multi-Institutional Thyroid Ultrasound Registry.

OBJECTIVES: The aim of this study was to compare how often fine-needle aspiration (FNA) would be recommended for nodules in unselected, low-risk adult patients referred for sonographic evaluation of thyroid nodules by ACR Thyroid Imaging Reporting and Data System (TI-RADS), the American Thyroid Association guidelines (ATA), Korean Thyroid Imaging Reporting and Data System (K-TIRADS), European Thyroid Imaging Reporting and Data System (EU-TIRADS), and Artificial Intelligence Thyroid Imaging Reporting and Data System (AI-TIRADS). METHODS: Seven practices prospectively submitted thyroid ultrasound reports on adult patients to the ACR Thyroid Imaging Research Registry between October 2018 and March 2020. Data were collected about the sonographic features of each nodule using a structured reporting template with fields for the five ACR TI-RADS ultrasound categories plus maximum nodule size. The nodules were also retrospectively categorized according to criteria from ACR TI-RADS, the ATA, K-TIRADS, EU-TIRADS, and AI-TIRADS to compare FNA recommendation rates. RESULTS: For 27,933 nodules in 12,208 patients, ACR TI-RADS recommended FNA for 8,128 nodules (29.1%, 95% confidence interval [CI] 0.286-0.296). The ATA guidelines, EU-TIRADS, K-TIRADS, and AI-TIRADS would have recommended FNA for 16,385 (58.7%, 95% CI 0.581-0.592), 10,854 (38.9%, 95% CI 0.383-0.394), 15,917 (57.0%, 95% CI 0.564-0.576), and 7,342 (26.3%, 95% CI 0.258-0.268) nodules, respectively. Recommendation for FNA on TR3 and TR4 nodules was lowest for ACR TI-RADS at 18% and 30%, respectively. ACR TI-RADS categorized more nodules as TR2, which does not require FNA. At the high suspicion level, the FNA rate was similar for all guidelines at 68.7% to 75.5%. CONCLUSION: ACR TI-RADS recommends 25% to 50% fewer biopsies compared with ATA, EU-TIRADS, and K-TIRADS because of differences in size thresholds and criteria for risk levels.

Quantification of gas exchange-related upward motion of the liver during prolonged breathholding-potential reduction of motion artifacts in abdominal MRI.

OBJECTIVE: To test the hypothesis that there is a measureable upward motion of the diaphragm during prolonged breath-holds that could have a detrimental effect on image quality in liver MRI and to identify factor that potentially influence the magnitude of this motion. METHODS: 15 healthy volunteers underwent MRI examination using prolonged breath-holds in the maximum inspiratory position and a moderate inspiratory position. Coronal T1 weighted three-dimensional gradient echo sequences of the entire thorax were acquired every 6 s during breath-holding allowing the calculation of total lung volume and the measurement of the absolute position of the dome of the liver. The potential impact of subject's gender, body mass index, and total lung capacity on the change in lung volume/diaphragmatic motion was assessed using random coefficient regression. RESULTS: All volunteers demonstrated a slow reduction of the total lung volume during prolonged breath-holding up to 123 ml. There was a measurable associated upward shift of the diaphragm, measuring up to 5.6 mm after 24 s. There was a positive correlation with female gender (p = 0.037) and total lung volume (p = 0.005) and a negative association with BMI (p = 0.012) for the maximum inspiratory position only. CONCLUSION: There is a measureable reduction of lung volumes with consecutive upward shift of the diaphragm during prolonged breath-holding which likely contributes to motion artifacts in liver MRI. ADVANCES IN KNOWLEDGE: There is a measureable gas exchange-related reduction of lung volumes with consecutive upward shift of the diaphragm during prolonged breath-holding which likely contributes to motion artifacts in liver MRI. Correcting for this predictable upward shift has potential to improve image quality.The magnitude of this effect does not seem to be related to gender, BMI or total lung capacity if a moderate inspiratory position is used.

Papillary Thyroid Carcinoma Recurrence: Low Yield of Neck Ultrasound With an Undetectable Serum Thyroglobulin Level.

OBJECTIVES: To assess the yield of neck ultrasound (US) when serum thyroglobulin (Tg) is undetectable (<0.1 ng/mL) compared to elevated serum Tg in patients with differentiated papillary thyroid carcinoma (PTC) treated with thyroidectomy and radioactive iodine 131 (RAI) ablation. METHODS: A retrospective chart review was conducted from 2010 through 2015 at an academic institution evaluating US results in patients with serum Tg levels obtained within 6 months of a neck US examination after thyroidectomy and RAI. The reference standard for recurrence was pathologic results from US-guided fine-needle aspiration (FNA) or follow-up for at least 1 year. RESULTS: Among 76 patients with undetectable serum Tg levels, there were 19 examinations in 18 patients in which US raised the possibility of recurrence. None of these 18 patients had recurrence by FNA (n = 8) or clinical follow-up of at least 1 year (n = 10). Among 65 patients with elevated serum Tg levels, there were 24 examinations in 22 patients in which US raised the possibility of recurrence. Twelve patients underwent FNA, with 9 patients (34.6%) showing PTC; 7 patients had follow-up neck US examinations showing stability of findings; and 3 patients were lost to follow up. The yield of neck US was significantly lower when serum Tg was undetectable compared to when levels were elevated (P = .001). CONCLUSIONS: Neck US did not identify recurrent PTC when the serum Tg level was undetectable in patients who underwent total thyroidectomy and RAI therapy. Eliminating neck US when serum TG levels are undetectable could decrease unnecessary imaging examinations without negatively affecting the ability to detect recurrent disease.

Bleeding Risk and Management in Interventional Procedures in Chronic Liver Disease.

The coagulopathy of liver disease is distinctly different from therapeutic anticoagulation in a patient. Despite stable elevated standard clot-based coagulation assays, nearly all patients with stable chronic liver disease (CLD) have normal or increased clotting. Common unfamiliarity with the limitations of these assays in CLD may lead to inappropriate and sometimes harmful interventions, including blood product transfusions before a procedure. Knowledge of the distinct hemostatic alterations in CLD can allow identification of the small subset of patients with clinically significant coagulopathy who can benefit from hematologic optimization before invasive procedures.