A Multicenter Study of Needle Size and Safety for Splenic Biopsy.

Background Splenic biopsy is rarely performed because of the perceived risk of hemorrhagic complications. Purpose To evaluate the safety of large bore (≥18 gauge) image-guided splenic biopsy. Materials and Methods This retrospective study included consecutive adult patients who underwent US- or CT-guided splenic biopsy between March 2001 and March 2022 at eight academic institutions in the United States. Biopsies were performed with needles that were 18 gauge or larger, with a comparison group of biopsies with needles smaller than 18 gauge. The primary outcome was significant bleeding after the procedure, defined by the presence of bleeding at CT performed within 30 days or angiography and/or surgery performed to manage the bleeding. Categorical variables were compared using the χ2 test and medians were compared using the Mann-Whitney test. Results A total of 239 patients (median age, 63 years; IQR, 50-71 years; 116 of 239 [48.5%] female patients) underwent splenic biopsy with an 18-gauge or smaller needle and 139 patients (median age, 58 years [IQR, 49-69 years]; 66 of 139 [47.5%] female patients) underwent biopsy with a needle larger than 18 gauge. Bleeding was detected in 20 of 239 (8.4%) patients in the 18-gauge or smaller group and 11 of 139 (7.9%) in the larger than 18-gauge group. Bleeding was treated in five of 239 (2.1%) patients in the 18-gauge or smaller group and one of 139 (1%) in the larger than 18-gauge group. No deaths related to the biopsy procedure were recorded during the study period. Patients with bleeding after biopsy had smaller lesions compared with patients without bleeding (median, 2.1 cm [IQR, 1.6-5.4 cm] vs 3.5 cm [IQR, 2-6.8 cm], respectively; P = .03). Patients with a history of lymphoma or leukemia showed a lower incidence of bleeding than patients without this history (three of 90 [3%] vs 28 of 288 [9.7%], respectively; P = .05). Conclusion Bleeding after splenic biopsy with a needle 18 gauge or larger was similar to biopsy with a needle smaller than 18 gauge and seen in 8% of procedures overall, with 2% overall requiring treatment. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Grant in this issue.

Can incorrect artificial intelligence (AI) results impact radiologists, and if so, what can we do about it? A multi-reader pilot study of lung cancer detection with chest radiography.

OBJECTIVE: To examine whether incorrect AI results impact radiologist performance, and if so, whether human factors can be optimized to reduce error. METHODS: Multi-reader design, 6 radiologists interpreted 90 identical chest radiographs (follow-up CT needed: yes/no) on four occasions (09/20-01/22). No AI result was provided for session 1. Sham AI results were provided for sessions 2-4, and AI for 12 cases were manipulated to be incorrect (8 false positives (FP), 4 false negatives (FN)) (0.87 ROC-AUC). In the Delete AI (No Box) condition, radiologists were told AI results would not be saved for the evaluation. In Keep AI (No Box) and Keep AI (Box), radiologists were told results would be saved. In Keep AI (Box), the ostensible AI program visually outlined the region of suspicion. AI results were constant between conditions. RESULTS: Relative to the No AI condition (FN = 2.7%, FP = 51.4%), FN and FPs were higher in the Keep AI (No Box) (FN = 33.0%, FP = 86.0%), Delete AI (No Box) (FN = 26.7%, FP = 80.5%), and Keep AI (Box) (FN = to 20.7%, FP = 80.5%) conditions (all ps < 0.05). FNs were higher in the Keep AI (No Box) condition (33.0%) than in the Keep AI (Box) condition (20.7%) (p = 0.04). FPs were higher in the Keep AI (No Box) (86.0%) condition than in the Delete AI (No Box) condition (80.5%) (p = 0.03). CONCLUSION: Incorrect AI causes radiologists to make incorrect follow-up decisions when they were correct without AI. This effect is mitigated when radiologists believe AI will be deleted from the patient's file or a box is provided around the region of interest. CLINICAL RELEVANCE STATEMENT: When AI is wrong, radiologists make more errors than they would have without AI. Based on human factors psychology, our manuscript provides evidence for two AI implementation strategies that reduce the deleterious effects of incorrect AI. KEY POINTS: • When AI provided incorrect results, false negative and false positive rates among the radiologists increased. • False positives decreased when AI results were deleted, versus kept, in the patient's record. • False negatives and false positives decreased when AI visually outlined the region of suspicion.

Ventriculogallbladder Shunt: Percutaneous Transhepatic Placement of the Distal Catheter.

BACKGROUND: Ventriculogallbladder (VGB) shunts are currently placed as a salvage procedure in treatment of hydrocephalus when all other options are exhausted. Although VGB shunts work well when successfully implanted, they are still rarely used because of the technical challenges with the traditional surgical technique. OBJECTIVE: To implant VGB shunts using a minimally invasive technique that is safer and less technically challenging. METHODS: We discussed our utilization of a percutaneous transhepatic approach to placement of the distal catheter into the gallbladder as a new technique that offers a solution to the established but surgically demanding current approach. We presented a complex patient with multiple failed shunts who underwent placement of a VGB shunt. RESULTS: The shunt was successfully placed and did not incur any complications or require any revisions in 5 yr. CONCLUSION: Given the safety and ease of this minimally invasive approach, we believe percutaneous transhepatic approach in VGB shunts should be considered as a reasonable option in patients with complex hydrocephalus.

Review of CT-guided trans-osseous biopsies.

Percutaneous image-guided biopsy is an invaluable technique in the management of a myriad of different conditions; however, percutaneous access to some targets remains challenging. Trans-osseous biopsy provides safe, high-yield access to many challenging lesions in the chest, abdomen, and pelvis which might otherwise require more invasive procedures, such as mediastinoscopy or surgery to establish a histological diagnosis. Additionally, trans-osseous biopsy is well tolerated and may reduce the risk of injury to intervening vital structures as compared to other percutaneous techniques. In this article we review the indications, technical challenges, alternative techniques, and potential complications of trans-sternal, trans-costal, trans-scapular, trans-vertebral, trans-iliac, and trans-sacral biopsies.

Unusual appearance of an adrenal ganglioneuroma.

Ganglioneuromas are rare tumors that occur spontaneously or arise from a poorly differentiated neuroblastic tumor. Although they are typically described in the pediatric population, they can occur in adults. Ganglioneuromas are often discovered incidentally and their typical imaging appearance, although non-specific, is that of a well-defined solid mass. We are presenting a case of a fat-containing adrenal lesion in a 53-year-old male. The extensive lipomatous changes within the lesion led to the presumption that it represented an adrenal myelolipoma. Pathology revealed a ganglioneuroma with extensive lipomatous changes. This is an uncommon presentation of an adrenal ganglioneuroma mimicking an adrenal myelolipoma. The diagnosis of an adrenal ganglioneuroma raises the possibility of syndromic associations for which patients may undergo genetic testing. We provide a review of typical imaging features of an adrenal ganglioneuroma and provide insight into the situations in which a ganglioneuroma can be suggested as a diagnostic consideration.

Liver Ultrasound Elastography: Review of Techniques and Clinical Applications.

Chronic liver disease remains a substantial worldwide problem. Accurate estimation of liver fibrosis is crucial for determining the stage of the disease, assessing the patient's prognosis and predicting treatment response. Staging hepatic fibrosis has traditionally been done with liver biopsy but clinical practice has been changing, partly because liver biopsy has several disadvantages: it is invasive; it is associated with rare but serious complications; and it is prone to sampling error representing a tiny portion of the total liver volume. An increasing number of non-invasive liver fibrosis assessment have been developed. These include elastographic methods involving ultrasound (US) and magnetic resonance (MR) imaging. In this review article we discuss the different ultrasound-based elastography techniques, their clinical applications and various confounding factors in the assessment of hepatic fibrosis that may affect the accuracy of the measurements.

CT-guided biopsy of pulmonary nodules ≤10 mm: Diagnostic yield based on nodules' lobar and segmental distribution.

PURPOSE: The aim of our study is to evaluate the diagnostic performance of CT-guided biopsy of lung nodules ≤10 mm based on their lobar and segmental location. MATERIALS AND METHODS: This was a retrospective study performed on 193 CT-guided percutaneous transthoracic needle biopsies of lung nodules ≤10 mm in greatest dimension, between January 1, 2013 and April 30, 2019. Biopsies were classified as either diagnostic or non-diagnostic based on final cytology and surgical pathology reports. Diagnostic results were those that met parameters for malignancy or a specific benign diagnosis, whereas atypical cells, non-specific benignity, or insufficient specimen were considered non-diagnostic. RESULTS: A total of 1577 CT-guided percutaneous transthoracic needle biopsies were reviewed. Of these, 193 nodules (12.24%) measured ≤10 mm and were selected for further analysis. Of the 193 biopsies, 138 yielded diagnostic results while 56 yielded nondiagnostic results (71% vs 29%, respectively). When analyzed by nodule location, the superior segments of the lower lobes boasted the highest diagnostic yield compared to nodules located in the basal segments of the lower lobes which had the lowest diagnostic yield (84.2% vs 64.7%, respectively). Nodules in the upper lobes and in the middle lobes had a diagnostic yield of 70% and 66.7%, respectively. CONCLUSION: The diagnostic performance of CT-guided biopsy of lung nodules ≤10 mm in diameter may be affected by lobar and segmental location. While the overall performance was good (diagnostic yield of 71%), the yield varied nearly 20% depending on location.

Abdominal wall and pelvic hernias: classic and unusual hernias and their mimics.

Abdominal and pelvic wall hernias are classically defined as a weakness or opening of the muscular wall through which abdominal or pelvic tissues protrude. The aim of this manuscript is to review the imaging findings of abdominal and pelvic wall hernias and their mimics and to discuss pearls and pitfalls for accurately diagnosing and classifying these entities.

Evidence Supporting LI-RADS Major Features for CT- and MR Imaging-based Diagnosis of Hepatocellular Carcinoma: A Systematic Review.

The Liver Imaging Reporting and Data System (LI-RADS) standardizes the interpretation, reporting, and data collection for imaging examinations in patients at risk for hepatocellular carcinoma (HCC). It assigns category codes reflecting relative probability of HCC to imaging-detected liver observations based on major and ancillary imaging features. LI-RADS also includes imaging features suggesting malignancy other than HCC. Supported and endorsed by the American College of Radiology (ACR), the system has been developed by a committee of radiologists, hepatologists, pathologists, surgeons, lexicon experts, and ACR staff, with input from the American Association for the Study of Liver Diseases and the Organ Procurement Transplantation Network/United Network for Organ Sharing. Development of LI-RADS has been based on literature review, expert opinion, rounds of testing and iteration, and feedback from users. This article summarizes and assesses the quality of evidence supporting each LI-RADS major feature for diagnosis of HCC, as well as of the LI-RADS imaging features suggesting malignancy other than HCC. Based on the evidence, recommendations are provided for or against their continued inclusion in LI-RADS. © RSNA, 2017 Online supplemental material is available for this article.

Gallbladder opacification on gadoxetate disodium-enhanced CT scan.

This study aimed to evaluate the radiologist's ability to identify excreted gadoxetate disodium within the gallbladder on CT scan. Thirty three healthy adults underwent imaging of the liver during work-up for potential liver donation. Three patients had undergone prior cholecystectomy and therefore were excluded. Imaging consisted of gadoxetate disodium-enhanced magnetic resonance cholangiography (MRC) and multiphase contrast-enhanced CT scan of the abdomen and pelvis. Two fellowship-trained abdominal imaging radiologists, who were blinded to the MRC images and the contrast agent used during MRC, independently reviewed the CT scans of the 30 patients that were included. The scans were evaluated for the presence or absence of abnormal hyperdensity within the gallbladder. Three patients did not receive intravenous gadoxetate disodium, 4 patients had their MRC after the CT scan, and 1 patient had the CT scans 5 days following the MRC. Twenty two patients had the CT scan within 24 h following the gadoxetate disodium-enhanced MRC. Of the 22 patients expected to have gadolinium in the gallbladder, both reviewers identified hyperdensity in the same 20 patients (90%). Both reviewers reported no abnormal hyperdensity within the gallbladder in the remaining 10 patients. CT scan can reveal excreted gadoxetate disodium within the gallbladder lumen and therefore gadoxetate disodium-enhanced CT scan can potentially play a role in the evaluation of cystic duct patency and work-up of acute cholecystitis.

Cholecystostomy Treatment in an ICU Population: Complications and Risks.

BACKGROUND: Percutaneous cholecystostomy tube placement has widely been used as an alternative treatment to cholecystectomy, especially in advanced disease or critically ill patients. Reported postprocedural complication rates have varied significantly over the last decade. The goal of this study is to evaluate the safety of percutaneous cholecystostomy tube treatment in critically ill patients. STUDY DESIGN: We performed a retrospective chart analysis of 96 critically ill patients who underwent cholecystostomy tube placement during an intensive care unit (ICU) stay between 2005 and 2010 in a tertiary care center in central Massachusetts. Complications within 72 hours of cholecystostomy tube placement and any morbidity or mortality relating to presence of cholecystostomy tube were considered. RESULTS: A total of 65 male and 31 female patients with a mean age of 67.4 years underwent percutaneous cholecystostomy tube placement during an ICU stay. Sixty-six patients experienced a total of 121 complications, resulting in an overall complication rate of 69%. Fifty-four of these complications resulted from the actual procedure or the presence of the cholecystostomy tube; the other 67 complications occurred within 72 hours of the cholecystostomy procedure. Ten patients died. Tube dislodgment was the most common complication with a total of 34 episodes. CONCLUSIONS: Cholecystostomy tube placement is associated with frequent complications, the most common of which is tube dislodgment. Severe complications may contribute to serious morbidity and death in an ICU population. Complication rates may be underreported in the medical literature. The potential impact of cholecystostomy tube placement in critically ill patients should not be underestimated.

Hepatocellular carcinoma recurrence pattern following liver transplantation and a suggested surveillance algorithm.

PURPOSE: This study aims to evaluate the recurrence pattern of hepatocellular carcinoma (HCC) following liver transplantation. MATERIALS AND METHODS: A total of 54 patients underwent liver transplantation for HCC; 9 patients developed biopsy-proven recurrent HCC (16.6%). The site of HCC recurrence along with other factors was analyzed. RESULTS: Seven patients were diagnosed with HCC prior to liver transplantation and 2 patients had incidental HCC in the explanted liver. Two patients had locoregional recurrence, 4 patients had distant metastasis, and 3 patients had synchronous locoregional recurrence and distant metastasis. CONCLUSION: A significant proportion of HCC recurrence following liver transplantation is extrahepatic.

Metastatic Renal Cell Carcinoma in a Hepatic Hemangioma: A Case Report and Review of the Literature.

We report the case of 55-year-old female with biopsy-proven clear cell renal cell carcinoma with a suspicious lesion found in the liver who presented for right radical nephrectomy and partial hepatectomy. Histologic evaluation of the hepatic specimen demonstrated metastatic renal cell carcinoma within a hepatic hemangioma. Herein we provide a review of the literature for this uncommon scenario.

Delayed splenic rupture presenting 70 days following blunt abdominal trauma.

Delayed splenic rupture following conservative management of splenic injury is an extremely rare complication. We report a case of an adult patient who presented with delayed splenic rupture necessitating splenectomy, 2 months following blunt abdominal trauma. Imaging at the initial presentation demonstrated only minimal splenic contusion and the patient was discharge following 24 hours of observation.

Gadoxetate disodium-enhanced liver MRI: gallbladder opacification patterns during hepatobiliary phase.

OBJECTIVE(S): To describe the different patterns of gallbladder lumen opacification on gadoxetate disodium-enhanced liver magnetic resonance imaging (MRI). METHODS: One hundred eighty-seven MRI examinations were reviewed by two abdominal imaging radiologists who described the different patterns of gallbladder opacification, based on comparing the post-contrast to the pre-contrast images. RESULTS: Four patterns of gallbladder opacification were identified, all based on the anti-dependent distribution of the excreted biliary contrast inside the gallbladder lumen. Contrast was identified at the level of the gallbladder neck, anti-dependant wall, and gallbladder fundus. One gallbladder completely filled with contrast. CONCLUSION(S): The opacification of the gallbladder lumen follows a distinctive anti-dependent distribution.

Renal biopsy: comparative yield of cranial versus caudal needle trajectory. An ex vivo analysis.

AIM: To compare the diagnostic quality of tissue cores obtained using cranial and caudal angulation of the renal biopsy needle. Comparison was made in terms of the number of glomeruli and proportion of renal cortex with medulla on pathological analysis. METHODS: A total of 40 desktop, renal biopsies were performed on 10 ex vivo porcine kidneys using two different targeting angles. Biopsies were obtained from the 'lower pole' of each kidney using both cephalad and caudad angulations of the biopsy needle. Ten 18-gauge semi-automated cutting needles were used during twenty biopsies obtained per each angle; two biopsies were made using each needle. The resulting samples were collected in 40 separate and labelled formalin containers according to the used targeting angle. Two pathologists blinded to the corresponding biopsy angles reviewed the samples in consensus. RESULTS: Samples with a cephalad targeting angle had a mean length of 14.5 mm with mean number of 9.6 glomeruli and average 82% cortex and 18% medulla. Samples obtained using a caudad needle angulation had a mean length of 14.1 mm with mean number of 11.6 glomeruli and on the average 99% cortex. The P-values comparing the two samples were as follows: 0.63 comparing the mean length of cores, 0.08 for number of glomeruli and 0.002 comparing the proportion of cortex. CONCLUSION: The proportion of cortical tissue in the core biopsy specimen using the caudad angle approach was statistically significantly higher, compared with the cephalad needle trajectory.

Incidentally detected misty mesentery on CT: risk of malignancy correlates with mesenteric lymph node size.

OBJECTIVE: To determine the natural history of incidentally detected misty mesentery on computed tomography (CT) and to correlate the risk of malignancy with size of mesenteric lymph nodes. METHODS: A retrospective review of all CT abdomen/pelvic examinations from January 1, 2004 through December 31, 2008 identified cases of misty mesentery. The largest mesenteric lymph node was measured, and additional areas of lymphadenopathy were identified. Follow-up was obtained by reviewing all subsequent CT examinations, clinical notes, and pathologic specimens. Patients were excluded if they had a known malignancy at the time of initial CT, CT or clinical history revealing a cause for the misty mesentery, or CT follow-up of less than 2 years. RESULTS: Thirty-seven patients with misty mesentery were included. The mean time from the original CT to the latest follow-up was 3.8 years. The largest lymph node measured less than 10 mm in 30 (81%) of 37 patients. All 30 patients demonstrated stable lymph node size, had no other regions with lymphadenopathy, and none developed malignancy. The largest lymph node was 10 mm or greater in 7 (19%) of 31 patients. Three of these patients developed non-Hodgkin lymphoma, 2 of which had other areas of lymphadenopathy. No cases of nonlymphomatous malignancy were identified. CONCLUSIONS: The development of malignancy in patients with incidentally detected misty mesentery correlates with mesenteric lymph node size. Patients with misty mesentery and largest mesenteric lymph node less than 10 mm without additional areas of lymphadenopathy demonstrate a benign course, and no further follow-up may be necessary.

Determination of cystic duct patency using hepatobiliary MRI with gadoxetate disodium: is T1 precontrast imaging necessary?

PURPOSE: To determine the need for precontrast T1-weighted imaging in determining cystic duct patency using hepatobiliary phase imaging with gadoxetate disodium-enhanced magnetic resonance imaging (MRI). MATERIALS AND METHODS: MRI exams using gadoxetate disodium from October 4, 2008 to April 14, 2010 were reviewed in a retrospective fashion. Two reviewers independently reviewed only the 20-minute T1-weighted delayed postcontrast images to determine the presence of excreted contrast in the gallbladder lumen. Contrast was deemed present if hyperintense signal material was seen in the antidependent portion of the gallbladder lumen. The actual presence of contrast in the gallbladder was determined by directly comparing the pre- and postcontrast T1-weighted images using consensus review. RESULTS: In all, 187 cases were included. Three (1.6%) were deemed indeterminate due to complete homogeneous opacification of the gallbladder. All three cases were identified as indeterminate by both reviewers. Of the remaining 184 cases, 136 filled (74%) and 48 did not fill (26%). Both reviewers correctly identified 136/136 cases of gallbladder filling. Reviewer A identified 47/48 cases of nonfilling and reviewer B identified 46/48 cases of nonfilling. Sensitivity and specificity were 100% and 98% for reviewer A and 100% and 96% for reviewer B, respectively. CONCLUSION: The presence of excreted contrast in the gallbladder lumen can be determined using gadoxetate disodium-enhanced MRI without precontrast T1-weighted imaging.