Navin, Patrick J.

ABSTRACT Chronic liver disease (CLD) is a major cause of global morbidity and mortality, with outcomes closely linked to the severity of liver fibrosis. While liver biopsy has historically been the reference standard for fibrosis staging, its invasiveness, sampling variability and limited suitability for longitudinal monitoring have driven the widespread adoption of non‐invasive tests (NITs). Imaging‐based biomarkers, particularly elastography, now play a central role in the clinical assessment and care pathway design. This review focuses on imaging techniques for non‐invasive assessment of liver fibrosis, with emphasis on elastography techniques: vibration‐controlled transient elastography (VCTE), ultrasound‐based shear wave elastography (SWE) and magnetic resonance elastography (MRE). Technical principles, advantages, limitations and implementation considerations are discussed to support informed selection across clinical contexts. VCTE offers rapid point‐of‐care assessment with extensive validation for identifying advanced fibrosis but is limited by operator dependence, reduced repeatability and lack of anatomical information. SWE provides real‐time, radiologist‐controlled assessment with improved applicability in obesity and ascites, though intervendor variability and operator dependence remain challenges. MRE demonstrates the highest diagnostic accuracy, reproducibility and technical success, with assessment of larger liver volume and strong performance across etiologies, albeit with limited access due to the requirement of an MRI system. Adjunct MRI biomarkers, including proton‐density fat fraction and iron‐corrected T1 mapping, further enhance liver phenotyping by characterising steatosis and fibro‐inflammatory activity. Understanding the strengths and limitations of each technique is essential for radiologists supporting multidisciplinary CLD management and service implementation, particularly in evolving healthcare environments such as Australia.

ABSTRACT Background Gastric emptying (GE) scintigraphy with 4‐h imaging and a radiolabeled chicken egg‐based meal (320 kcal, 30% fat) is the standard test for gastroparesis at Mayo Clinic, with an intraindividual coefficient of variation (COV intra ) of 23.8% for GE half emptying time (T 1/2 ). Alternative meals for patients with dietary restrictions, including egg allergies or vegan diets, are lacking, limiting test accessibility. The study aimed to establish a vegan, lactose‐, nut‐, and gluten‐free meal with similar caloric and fat content to the egg meal and to assess its performance in GE studies. Methods In Vitro: 99m Tc binding to egg meal over 4 h was compared to a calorically and nutritionally similar vegan alternative, JUST Egg, using a validated in vitro model simulating gastric conditions of pH, pepsin, and stirring. In Vivo: 10 healthy participants underwent randomized crossover GE scintigraphy with standard and vegan meals, spaced ≥ 3 days apart to measure GE% at 2 h, 4 h, and GE T 1/2 . Group comparisons and variance analysis included Rank Sum tests and Bland–Altman plots. Key Results In Vitro: A strong correlation ( R = 0.975, p ‐value < 0.01) between 99m Tc binding in the egg and vegan egg models was observed. Minimal variance (< 10%) was recorded at all time points. In Vivo: GE at 4 h and GE T 1/2 showed non‐statistically significant mean differences, < 2% and < 10 min respectively, between both meals. The intra‐individual variability was 18.8%. Conclusions and Inferences The vegan meal demonstrated in vitro stability, in vivo performance comparable to the egg meal, and a COV intra of 18.8%, which was lower than the 23.8% reported in repeat egg meal GE studies. Trial Registration ClinicalTrials.gov number NCT06991036 ( https://clinicaltrials.gov/study/NCT06991036?term=NCT06991036&rank=1 )

Radiologists are integral members of the interdisciplinary team for patients with mucinous appendiceal neoplasms and can directly affect care by suggesting the diagnosis of pseudomyxoma peritonei, optimizing imaging protocols for evaluating peritoneal implants, and reporting the primary tumor and spilled tumor cells thoroughly.

Abstract Objectives: Radiologist participation in multidisciplinary tumor board can be time-consuming and demanding, requiring substantial preparation. Anecdotally radiologist participation is felt to help identify discrepancies in previous interpretations; however, there are limited data assessing the actual impact of their tumor board review on patient management. This prospective study aims to evaluate how the reinterpretation of outside imaging and review at hepatobiliary tumor board (HBTB) affects the diagnosis and management of patients with hepatobiliary neoplasms. Methods: This prospective analysis included all patients presented at the weekly HBTB between 6/13/2023 - 6/25/2024. One radiologist reviewed the available reports of outside imaging, the local reinterpretation of outside imaging, the updated local imaging, and documented conclusions from discussion of the case at HBTB. HBTB included 4 radiologists who had reviewed each case. Discrepancies (presence/absence, number, and reasons for) were recorded. When discrepancies occurred, the impact on patient management (5-point Likert scale) was determined by two of the radiologists present at the HBTB in consensus, with input from clinicians if needed. A six-month follow-up was performed to confirm suspected diagnoses. Results: 208 cases (128 males, 104 chronic liver disease patients) were presented at HBTB. Disagreements in the detection or characterization of lesions were found in 59/208 (28.4%) of cases. A change in management occurred in 38/59 (64.6%) of these discrepant cases. In cases with recorded discrepancies in which follow-up confirmation was available, the final interpretation was confirmed in 34/41 (82.9%) of cases. Conclusion: Our study found a discrepant interpretation in nearly one-third of cases presented at a weekly HBTB and a resultant change in management in 65% of those cases. These findings highlight the importance of reinterpretation of prior imaging studies and the presence of radiologists at HBTB to guide optimal patient management.

Abstract Adrenal infections are considered clinically important but often go unrecognized, with a significant number of cases only diagnosed post-mortem. The limited evidence regarding imaging findings in the literature emphasizes the need to detect and diagnose these infections early in disease course to improve patient outcomes. A range of microorganisms, including fungi, viruses, parasites, and bacteria, can directly or indirectly affect the morphology and function of the adrenal glands. When evaluating a patient with adrenal infection, several immunological and hormonal factors should be considered, such as the status of the hypothalamic-pituitary-adreno cortical axis and the serum cortisol level. Moreover, certain microorganisms specifically target one of the zones of the adrenal glands or vascular supply, resulting in distinct imaging manifestations. The purpose of this article is to describe the fundamental clinical features and imaging manifestations associated with adrenal infections, enabling radiologists to make informed interpretations and contribute to accurate diagnostic assessments.

Radiologists play a key role in the management of renal masses, and it is important to understand the nonsurgical treatment options for solid renal masses, typical imaging findings after treatment, common complications, and methods to avoid pitfalls.

49 Background: Ductal carcinoma (DC) is the second most commonly encountered histologic variant of prostate cancer. Previous studies have described its molecular features and aggressive behavior, but few have explored the performance of PSMA PET/CT in the initial staging and follow-up of DC. Methods: To address this gap, we performed a single-institution retrospective analysis using the Mayo Clinic PSMA PET database. All patients receiving a PSMA PET/CT scan in the interval of January 1, 2021, to December 31, 2022, were eligible for inclusion. Cases were filtered and categorized by histology at the time of diagnosis to select for pure DAC and mixed ductal variants. Trained research personnel annotated disease- and treatment-related variables. A board-certified radiologist performed tumor burden segmentation with calculations of SUV max, total lesion SUV mean and volume, and total lesion uptake, and ascribed a miPSMA expression score. Results: We queried 1792 patients from our PSMA PET/CT registry and identified 32 (1.8%) patients with a pathologically confirmed DC, including 8 (25%) patients with pure ductal and 25 (75%) patients with mixed histology. The indication for PSMA PET/CT was biochemical progression or restaging for 29 (91%) patients and initial staging for 3 (9%) patients. The median (IQR) time from prostate cancer diagnosis to PSMA PET scan was 41.6 (11.5-64.7) months, during this time 50% (n= 16) of patients developed CRPC. At the time of the PSMA PET/CT scan, the median age was 70 years, the median (IQR) PSA was 0.5 ng/mL (0.2-2.6). The distribution of metastatic spread and quantitative imaging parameters from PSMA PET are shown in the Table. Conclusions: Despite low PSA at the time of imaging, PSMA PET/CT frequently detected high volume osseous and/or visceral metastases in patients with DC. However, it is noteworthy that more than 50% of patients with DC had a low miPSMA score (0-1). Additional studies are needed to better understand the performance of novel imaging modalities when evaluating variant prostate cancers. [Table: see text]