ABSTRACT:The purpose of this study is to investigate the diagnostic accuracy of a new noninvasive imaging technique, ultrasound-guided attenuation parameter (UGAP), in diagnosing hepatic steatosis. This single-center retrospective study included 81 UGAP studies performed to guide therapy between July 2022 and June 2023 at a large academic medical center. Patients with either liver biopsy or Magnetic resonance-based proton-density fat fraction (MRI-PDFF) within 12 months of US-UGAP imaging, irrespective of order, were included. Patient demographics, body mass index, liver function tests, UGAP values, MRI-PDFF values, and liver biopsy results were obtained from a review of the medical records. Presence of steatosis was defined as PDFF >5.2% or >5% of hepatocytes with steatosis at pathology. Area under the ROC curve (AUROC) was used to measure UGAP accuracy for the detection of hepatic steatosis with statistical significance P < 0.05. There was a significant positive correlation between UGAP and MRI-PDFF (r = 0.463; P < 0.001; confidence interval [CI]: 0.220;0.651). The AUROC to differentiate absence of steatosis (n = 21) from presence of steatosis (n = 32) for UGAP with MRI as the gold standard was 0.760 (P < 0.001; CI: 0.623;0.867). A UGAP value >0.66 had 78% sensitivity and 67% specificity to identify steatosis presence on MRI-PDFF. The AUROC to differentiate absence of steatosis (n = 11) from presence of steatosis (n = 21) for UGAP with pathology as the gold standard was 0.894 (P < 0.001; CI: 0.734;0.974). A UGAP value >0.57 had 100% sensitivity and 64% specificity to identify steatosis presence at pathology. UGAP is an accurate measure for detecting the presence of hepatic steatosis and may be a noninvasive method for metabolic dysfunction-associated steatotic liver disease diagnosis and follow-up.

Gallbladder (GB) polyps are a common incidental finding on sonography, but only a small fraction of polyps become GB cancer. The Society of Radiologists in Ultrasound (SRU) consensus committee recently performed an extensive literature review and published guidelines for GB polyp follow-up/management to provide clarity among the many heterogeneous recommendations that are available to clinicians. As these guidelines have become adopted into clinical practice, challenging clinical scenarios have arisen including GB polyps in primary sclerosing cholangitis (PSC), high risk geographic/genetic patient populations, shrinking polyps, pedunculated vs sessile polyps, thin vs thick stalked polyps, vascular polyps and multiple polyps. According to the SRU guidelines, clinicians should refer to gastroenterology guidelines when managing GB polyps in patients with known PSC. If patients at high geographic/genetic risk develop GB polyps, ‘extremely low risk’ polyps may be managed as ‘low risk’ and 10–14 mm ‘extremely low risk’ or ‘7–14 mm’ low risk polyps that decrease in size by ≥ 4 mm require no follow-up. Thin-stalked or pedunculated polyps are ‘extremely low risk’ and thick-stalked pedunculated polyps are ‘low risk’. Sessile polyps are ‘low risk’ but should receive immediate specialist referral if features suggestive of GB cancer are present. Neither polyp multiplicity nor vascularity impact risk of GB cancer and follow up should be based on morphology alone.

BACKGROUND:Thromboelastography (TEG) informs the need for blood product transfusions to prevent procedural bleeding complications in patients with cirrhosis. We aimed to evaluate the impact of using a TEG-based transfusion protocol on blood product utilization before paracentesis and the post-paracentesis hemoperitoneum (PPH) incidence. METHODS:We conducted an ambispective analysis of patients with cirrhosis who underwent paracentesis from 2017 to 2021. In May 2019, we enacted a TEG-based transfusion protocol to guide pre-paracentesis blood product use. Patients with platelets < 20,000 or international normalized ratio ≥ 4 underwent TEG and received blood products if r value > 10 min or MA <30 mm. Patients were divided into pre-TEG and post-TEG protocol cohorts based on the date of paracentesis. Pre-paracentesis blood product transfusions in the form of platelets, fresh frozen plasma, and cryoprecipitates were recorded. PPH was defined as a decrease in hemoglobin of ≥1 g and the presence of blood on diagnostic imaging and/or the need for therapeutic intervention. RESULTS:A total of 483 patients underwent 1281 paracenteses. The main etiologies of cirrhosis were alcohol (43%) and NASH (25%), and the mean MELD-sodium was 22±6. Pre-TEG and post-TEG protocol cohort sizes were similar: 253 patients and 607 paracenteses versus 230 patients and 674 paracenteses. After TEG-protocol implementation, blood product transfusions decreased significantly (228 vs. 49 products, p<0.001) with associated cost savings. One patient in each cohort developed PPH. CONCLUSION:Implementation of a pre-paracentesis TEG-based transfusion protocol for patients with cirrhosis successfully resulted in decreased blood product use with no associated increase in incidence of PPH.

Background: The American College of Radiology Thyroid Imaging Reporting and Data System for ultrasound classification of malignancy risk was developed to better triage thyroid nodules for fine-needle aspiration biopsy. To examine further, we compared thyroid cytologic classification rates in nodules before and after institutional Thyroid Imaging Reporting and Data System implementation. Methods: Cytology diagnoses by Bethesda criteria (categories I-VI) from January 2014 to October 2021 were retrieved; observed changes in yearly category frequency were analyzed by linear regression; and pooled cohorts of pre- (2014-2018) and post-Thyroid Imaging Reporting and Data System (2019-2021) cytology call rates were compared. Results: Overall, 7,413 cytologic specimens were included (range/year 715-1,44 4). From 2014 to 2021, the proportion of benign (Bethesda category II) diagnosis per year declined stepwise from 49.7% to 19.4%, and atypia of undetermined significance/follicular lesion of undetermined significance (Bethesda category III) increased sequentially from 21.3% to 51.5%. Between 2014 and 2021, Bethesda category III diagnosis increased on average by 4.8% per year (95% confidence internal, 3.29-5.54; P < .001) and Bethesda category II results decreased on average by 4.4% per year (95% confidence interval, 6.29-3.42; P < .001). When comparing pre- and post-Thyroid Imaging Reporting and Data System, the proportion of Bethesda category II cytology results decreased (43.1% vs 21%; P =.001) while Bethesda category III (28.3% vs 47.7%; P = .002) and Bethesda category V (1.1% vs 1.7%; P = .015) results increased. Conclusion: After implementation of American College of Radiology Thyroid Imaging Reporting and Data System ultrasound criteria, we observed a 2.5-fold decline in the rate of benign cytology and an increase in the proportion of atypia of undetermined significance/follicular lesion of undetermined significance results.

PURPOSE:To study trends in volume and reimbursement for percutaneous kidney biopsy (PKB) by physicians and advanced practice providers (APPs) for Medicare enrollees from 2011-2021.METHODS:Claims from the Medicare Part B Physician/Supplier Procedure Master File (a national Medicare database) for 2011-2021 were extracted using Current Procedural Terminology codes for PKB. Total volumes were compared by provider specialty. Non-facility reimbursement, work Relative Value Unit (RVU) non-facility practice expense RVU, and malpractice RVU were compared.RESULTS:Between 2011 and 2021, total volume of PKB by physicians and APPs increased from 30,753 to 34,090 (10.9%), with a peak of 37,882 in 2019 prior to the COVID 19 pandemic. Radiology performed the majority of procedures during the study period. Relative share for radiology increased from 67.6% to 81.1% while the relative share for internal medicine/nephrology decreased from 24.3% to 14.3%, accelerating between 2019 and 2020. Volume and relative share for APPs marginally increased (from 0.9% to 1.2%). Non-facility reimbursement decreased from $578.96 in 2010 to $568.76 in 2021 (1.7%), work RVU decreased from 2.63 to 2.38 (9.5%), non-facility practice expense RVU decreased from 14.10 to 13.71 (2.8%), and malpractice RVU decreased from 0.31 to 0.21 (32.3%).CONCLUSION:Volume and total share of PKB performed by radiology increased over the study period. Conversely, internal medicine/nephrology performed fewer kidney biopsies. Despite the expanding role for APPs in other image-guided procedures, very few PKBs were performed by APPs throughout the study period. Reimbursement and RVU for PKB declined over the study period.

Abstract Gallbladder polyps (GPs) are a common incidental finding on ultrasound; however, important differences in recommended management exist among professional society guidelines. An electronic survey was sent to 189 fellows of the Society of Radiologists in Ultrasound. Main outcomes included preferences and current practice patterns for evaluation, management, and surveillance of GPs as well as personal lifetime experience with gallbladder sonography and GPs. A total of 64 subjects (34%) with experience in gallbladder sonography completed the study. The estimated combined total number of gallbladder scans seen by the responders was 3,071,880. None of fellows had ever seen a pedunculated GP <1 cm detected on ultrasound that was proven to be malignant at the time of detection or during subsequent follow-up. All of the fellows used size as a feature to stratify recommendations. The median size threshold currently used by Society of Radiologists in Ultrasound fellows for recommending ultrasound follow-up was 6 mm, and their preferred threshold was 7 mm. The median size threshold for recommending surgical consultation was 10 mm, and the preferred threshold was 10 mm. Wall thickening and shape were considered important factors by 76% and 67% of respondents, respectively. Society of Radiologists in Ultrasound fellows tend to provide recommendations most similar to the American College of Radiology and Canadian Association of Radiology guidelines for management of GPs. Many would prefer guidelines that result in fewer recommendations for follow-up and surgical consultation. Despite a substantial combined experience, this survey did not uncover any case of a small GP that was malignant.

PURPOSE:To study trends in volume and reimbursement for paracentesis and thoracentesis by physicians and advanced practice providers (APPs) after the introduction of discreet Current Procedural Terminology codes for image guidance.METHODS:Medicare claims for 2012 to 2018 (paracentesis) and 2013 to 2018 (thoracentesis) were extracted using Current Procedural Terminology codes for blind and image-guided paracentesis and thoracentesis. Total volumes were analyzed by provider specialty. Nonfacility reimbursement and relative value units were compared.RESULTS:For blind paracentesis, volume decreased from 17,393 to 12,226 procedures from 2012 to 2018. Conversely, volume of image-guided paracentesis increased from 171,631 to 253,834 procedures. Radiology performed the majority of image-guide paracentesis (83.9% in 2012 and 77.1% in 2018). Volume and relative share for APPs dramatically increased (from 10.2% to 15.8%). For blind thoracentesis, volume decreased from 26,716 to 15,075 procedures from 2013 to 2018. Conversely, volume of image-guided thoracentesis increased from 187,168 to 222,673 procedures. Radiology performed the majority of image-guided thoracentesis (73.6% in 2013 and 66.2% in 2018). Volume and relative share for APPs dramatically increased (from 7.7% to 12.9%). Although reimbursement for both image-guided paracentesis and thoracentesis decreased, their reimbursement remained higher than that of blind paracentesis and thoracentesis throughout the study period.CONCLUSION:A higher percentage of these procedures are being performed using image guidance; radiologists performed a growing number but declining percentage of image-guided paracentesis and thoracentesis. APPs are playing an increasing role, particularly using image guidance. Given decreasing reimbursement for these procedures, APPs can provide a large cost advantage in procedural radiology practices.

Gallbladder polyps (also known as polypoid lesions of the gallbladder) are a common incidental finding. The vast majority of gallbladder polyps smaller than 10 mm are not true neoplastic polyps but are benign cholesterol polyps with no inherent risk of malignancy. In addition, recent studies have shown that the overall risk of gallbladder cancer is not increased in patients with small gallbladder polyps, calling into question the rationale for frequent and prolonged follow-up of these common lesions. In 2021, a Society of Radiologists in Ultrasound, or SRU, consensus conference was convened to provide recommendations for the management of incidentally detected gallbladder polyps at US. See also the editorial by Sidhu and Rafailidis in this issue.

To assess the accuracy of MRI-derived liver surface nodularity (LSN) score for staging of hepatic fibrosis in patients with non-alcoholic fatty liver disease (NAFLD). Forty-seven patients with clinicopathological diagnosis of NAFLD who underwent 1.5-T liver MRI within 12 months of liver biopsy were included. Axial non-contrast T1-weighted 3D GRE was used for image analysis. LSN of the left lobe was measured using a custom semiautomated software. Histopathologic analysis (F0–F4) served as the reference standard for staging of fibrosis. Mann-Whitney test and Spearman’s correlation coefficient were used to compare LSN scores between different stages of fibrosis and to assess the correlation. Diagnostic performance of LSN score for detection of significant (F2–F4) and advanced (F3–F4) fibrosis was assessed by receiver operating characteristics (ROC) curve. p value of less than 0.05 was considered statistically significant different. Twenty-one subjects had advanced fibrosis. The LSN scores among different stages of fibrosis were significantly different (p < 0.001). The correlation between LSN score and stage of fibrosis was also strong (ρ = 0.71; p < 0.001). The areas under ROC curves for detection of significant and advanced fibrosis were 0.80 (95% CI 0.66–0.95) and 0.86 (95% CI 0.75–0.97), using a threshold of 2.23 and 2.44, respectively. This method showed 81% sensitivity and 88% specificity for detection of advanced fibrosis. MR-based LSN score is a promising non-invasive objective tool for detection of advanced fibrosis in patients with NAFLD. • Liver surface nodularity (LSN) score is a fast retrospective method for precise quantification of nodularity of liver surface. • MR-based LSN score is a promising non-invasive objective tool to accurately detect different stages of fibrosis in patients with non-alcoholic fatty liver disease (NAFLD).

OBJECTIVE. The goal of this study was to assess the correlation between CT-derived texture features of pancreatic ductal adenocarcinoma (PDAC) and histologic and biochemical markers of response to neoadjuvant treatment as well as disease-free survival in patients with potentially resectable PDAC. SUBJECTS AND METHODS. Thirty-nine patients completed this prospective study protocol between November 2013 and December 2016. All patients received neoadjuvant chemotherapy, underwent surgical resection, and had histologic grading of tumor response. Similar CT protocol was used for all patients. Pancreatic (late arterial) phase of pre- and posttreatment CT scans were evaluated. Histogram analysis and spatial-band-pass filtration were used to extract textural features. Correlation between textural parameters, histologic response, biochemical response, and genetic mutations was assessed using Mann-Whitney test, chi-square analysis, and multivariate logistic regression. Association with disease-free survival was assessed using Kaplan-Meier method and Cox model. RESULTS. Pretreatment mean positive pixel (MPP) at fine- and medium-level filtration, pretreatment kurtosis at medium-level filtration, changes in kurtosis, and pretreatment tumor SD were statistically different between patients with no or poor histologic response and favorable histologic response (p < 0.05). Changes in skewness and kurtosis at medium-level filtration significantly correlated with biochemical response (p < 0.01). On the basis of multivariate analysis, patients with higher MPP at pretreatment CT were more likely to have favorable histologic response (odds ratio, 1.06; 95% CI, 1.002-1.12). The Cox model for association between textural features and disease-free survival was statistically significant (p = 0.001). CONCLUSION. Textural features extracted from baseline pancreatic phase Cl' imaging of patients with potentially resectable PDAC and longitudinal changes in tumor heterogeneity can be used as biomarkers for predicting histologic response to neoadjuvant chemotherapy and disease-free survival.

Orthotopic liver transplant (OLT) is established as the definitive treatment of choice for end stage liver disease. Over the years, refined surgical techniques as well as advancements in organ preservation and immunosuppressive regimens have improved graft and patient survival rates. Imaging has also contributed to improved graft and patient survival. Ultrasound is the initial investigation of choice for evaluation of post-transplant anatomy and for identifying early complications. A thorough knowledge of surgical techniques and normal post-operative appearance of the OLT is needed to accurately identify and characterize graft complications. The objective of this article is to review the sonographic findings of normal liver transplant as well as post-operative complications. Indications and contraindications for OLT as well as different surgical techniques will also be briefly reviewed.

To investigate the performance of MR-based texture analysis (TA) for the assessment of hepatic fibrosis in patients with nonalcoholic fatty liver disease (NAFLD). Fifty-four adult patients (33 females, 21 males, mean age 49.8 ± 13.5 years) with biopsy-proven NAFLD were enrolled and underwent MR imaging on a 1.5 T system. TA parameters were extracted on axial noncontrast 3D-GRE T1W images (slice thickness = 4.6 mm) using a commercially available research software (TexRAD). Receiver operating curves (ROC), areas under the ROC (AUROC) and 95% confidence intervals (CI) were calculated to assess the accuracy of each TA parameter for the diagnosis of significant (F ≥ 2) and advanced fibrosis (F ≥ 3). The correlation between TA and histopathological features of nonalcoholic steatohepatitis (NASH) was tested calculating the Spearman’s rank correlation coefficient (ρ). Thirty-seven (68%) subjects had significant fibrosis and 20 (37%) had advanced fibrosis. The TA parameters with the best performance were standard deviation (SD) and entropy, respectively, with AUROC 0.755 (95% CI 0.619–0.862, p ≤ 0.0002) and 0.769 (95% CI 0.634–0.873, p < 0.0001) for significant fibrosis and AUROC 0.746 (95% CI 0.609–0.854, p ≤ 0.0004) and 0.754 (95% CI 0.618–0.861, p ≤ 0.0002) for advanced fibrosis. SD and entropy demonstrated a moderate correlation with the degree of fibrosis (ρ = 0.457 and 0.480; p < 0.01). No significant correlation was found between TA parameters and other histopathological features of NASH. Entropy and SD extracted on T1-weighted MR images have fair accuracy for the diagnosis of significant and advanced hepatic fibrosis in patients with NAFLD.

INTRODUCTION:At our institution, almost all thyroid fine-needle aspiration (FNA) procedures are performed by either Endocrinology or Radiology personnel. In this study, we compared the cytology and molecular adequacy rates of these 2 thyroid FNA practices, which differ on several aspects of specimen procurement.MATERIALS AND METHODS:All thyroid FNA specimens from Endocrinology and Radiology practices between September 2008 and December 2016 were included. Over this time frame, the molecular testing modality transitioned from polymerase chain reaction (PCR)-based (7-gene panel era) to next generation sequencing (NGS)-based (ThyroSeq era). In measuring cytology adequacy, the Bethesda System unsatisfactory rate was determined. Molecular adequacy was categorized as Optimal, Limited Thyroid Epithelial Cells, Limited Nucleic Acids, or Failed. These parameters were compared for the 2 practices.RESULTS:The study cohorts comprised 5810 specimens from Endocrinology and 4597 from Radiology. More Endocrinology specimens were satisfactory for cytology diagnosis than those from Radiology (94.7% versus 90.0%, P < 0.001). For molecular adequacy, fewer Endocrinology specimens were optimal than specimens from Radiology for both the 7-gene panel era (76.2% versus 82.9%, P < 0.001) and the ThyroSeq era (88.1% versus 91.9%, P = 0.049).CONCLUSIONS:The 2 thyroid FNA practices varied inversely in their adequacy rates for cytology and molecular testing. Had one practice been superior for both cytology and molecular adequacy, a recommendation for the method of choice would have been straightforward. However, our results show that optimization of FNA practice for the current practice of thyroid cytology requires further investigation due to the complex nature of specimen procurement.

OBJECTIVE We describe the indications, surgical technique, outcome, and imaging findings in patients with pancreatic ductal adenocarcinoma (PDAC) treated with distal pancreatectomy and celiac artery resection (modified Appleby procedure). CONCLUSION Distal pancreatectomy and celiac artery resection is a feasible surgery in selected patients with locally advanced PDAC. Knowledge of surgical technique and imaging features may aid radiologists in identifying patients with locally invasive PDAC who might benefit from resection and identifying characteristic distal pancreatectomy and celiac artery resection complications.

OBJECTIVE. The aim of the present study was to compare the diagnostic accuracy of liver stiffness measurements (LSMs) obtained using MR elastography (MRE), transient elastography (TE), and 2D shear wave elastography (SWE) in patients with biopsy-proven nonalcoholic fatty liver disease (NAFLD). SUBJECTS AND METHODS. We prospectively enrolled 62 adult subjects (mean age [± SD], 50 ± 13 years; 58% women; body mass index [weight in kilograms divided by the square of height in meters], 35 ± 7). Two-dimensional SWE, MRE, and TE were performed at a mean of 105 ± 86 days after liver biopsy. The area under the ROC curve (AUROC) values and 95% CIs for the corresponding LSMs (expressed in kilopascals) were calculated, with significant fibrosis (Metavir liver fibrosis score, F2-F4) and advanced fibrosis (F3-F4) used as outcome measures. Pairwise comparisons of AUROC values were conducted using the DeLong test. Statistical significance was set at p < 0.05. RESULTS. For the 62 subjects, valid LSMs were obtained for 57 subjects with the use of 2D SWE, for 59 subjects with TE, for 59 subjects with MRE, and for 54 subjects with all three modalities combined. The AUROC values (95% CIs) of 2D SWE, TE, and MRE for the diagnosis of significant fibrosis were 0.80 (0.67-0.92), 0.77 (0.64-0.89), and 0.85 (0.74-0.95), respectively. The AUROC values (95% CIs) of 2D SWE, TE, and MRE for the diagnosis of advanced fibrosis were 0.89 (0.80-0.98), 0.86 (0.77-0.95), and 0.95 (0.89-1.00), respectively. Pairwise comparisons revealed similar diagnostic accuracy for significant fibrosis (2D SWE vs MRE, p = 0.431; 2D SWE vs TE, p = 0.317; and MRE vs TE, p = 0.052) and advanced fibrosis (2D SWE vs MRE, p = 0.348; 2D SWE vs TE, p = 0.293; and MRE vs TE, p = 0.059). CONCLUSION. For patients with biopsy-proven NAFLD, 2D SWE, MRE and TE exhibited comparable and very good to excellent diagnostic accuracy for advanced fibrosis and comparable but lower accuracy for significant fibrosis.

OBJECTIVE:An American Association for the Study of Liver Diseases (AASLD) consensus document stressed the importance of obtaining sufficient liver biopsy specimens to minimize sampling errors. Many centers continue to use smaller-diameter core systems to minimize perceived complication risks. The objective of this study was to assess the impact of core gauge (18- vs 16-gauge) on specimen adequacy and procedural complications.SUBJECTS AND METHODS:One hundred fifty patients referred for liver biopsy were randomized to undergo 16- or 18-gauge ultrasound (US)-guided core biopsy. Hemorrhage was qualitatively evaluated, and pain was assessed using a 10-point rating scale. The length and number of portal tracts per specimen were assessed. On the basis of the AASLD guidelines, specimen adequacy was defined as 11 or more portal tracts. Differences in pathology metrics and pain scoring were assessed using chi-square and linear regression models.RESULTS:No significant hemorrhage occurred in either group, and there was no difference in postbiopsy pain scores. The mean specimen length obtained with 16-gauge needles was less than that obtained with 18-gauge needles (1.7 vs 1.9 cm, p = 0.03). The mean number of portal tracts obtained with 16-gauge biopsies was greater than obtained with 18-gauge systems (14 vs 13, p = 0.03); 85% of 16-gauge biopsy specimens and 80% of 18-gauge biopsy specimens were adequate on the basis of the AASLD criteria, although this difference was not statistically significant.CONCLUSION:US-guided 18- and 16-gauge core biopsies are similarly safe. A large percentage of 18- or 16-gauge specimens are inadequate when AASLD quality control adequacy thresholds are applied, and specimen adequacy is not significantly affected by biopsy gauge.