Comparing the Diagnostic Accuracy of Ultrasound and CT in Evaluating Acute Cholecystitis

Computed tomography versus ultrasound for the diagnosis of acute cholecystitis: a systematic review and meta-analysis

OBJECTIVES

Some patients undergo both computed tomography (CT) and ultrasound (US) sequentially as part of the same evaluation for acute cholecystitis (AC). Our goal was to perform a systematic review and meta-analysis comparing the diagnostic performance of US and CT in the diagnosis of AC.

MATERIALS AND METHODS

Databases were searched for relevant published studies through November 2023. The primary objective was to compare the head-to-head performance of US and CT using surgical intervention or clinical follow-up as the reference standard. For the secondary analysis, all individual US and CT studies were analyzed. The pooled sensitivities, specificities, and areas under the curve (AUCs) were determined along with 95% confidence intervals (CIs). The prevalence of imaging findings was also evaluated.

RESULTS

Sixty-four studies met the inclusion criteria. In the primary analysis of head-to-head studies (n = 5), CT had a pooled sensitivity of 83.9% (95% CI, 78.4-88.2%) versus 79.0% (95% CI, 68.8-86.6%) of US (p = 0.44). The pooled specificity of CT was 94% (95% CI, 82.0-98.0%) versus 93.6% (95% CI, 79.4-98.2%) of US (p = 0.85). The concordance of positive or negative test between both modalities was 82.3% (95% CI, 72.1-89.4%). US and CT led to a positive change in management in only 4 to 8% of cases, respectively, when ordered sequentially after the other test.

CONCLUSION

The diagnostic performance of CT is comparable to US for the diagnosis of acute cholecystitis, with a high rate of concordance between the two modalities.

CLINICAL RELEVANCE STATEMENT

A subsequent US after a positive or negative CT for suspected acute cholecystitis may be unnecessary in most cases.

KEY POINTS

When there is clinical suspicion of acute cholecystitis, patients will often undergo both CT and US. CT has similar sensitivity and specificity compared to US for the diagnosis of acute cholecystitis. The concordance rate between CT and US for the diagnosis of acute cholecystitis is 82.3%.

2024 Clinical Practice Guideline Update by the Infectious Diseases Society of America on Complicated Intraabdominal Infections: Diagnostic Imaging of Suspected Acute Cholecystitis and Acute Cholangitis in Adults, Children, and Pregnant People

This article is part of a clinical practice guideline update on the risk assessment, diagnostic imaging, and microbiological evaluation of complicated intraabdominal infections in adults, children, and pregnant people, developed by the Infectious Diseases Society of America. In this article, the panel provides recommendations for diagnostic imaging of suspected acute cholecystitis and acute cholangitis. The panel's recommendations are based on evidence derived from systematic literature reviews and adhere to a standardized methodology for rating the certainty of evidence and strength of recommendation according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach.

Pericholecystic Fat Stranding as a Predictive Factor of Length of Stays of Patients with Acute Cholecystitis: A Novel Scoring Model

Background: The 2018 Tokyo Guidelines (TG18) are used to classify the severity of acute cholecystitis (AC) but insufficient to predict the length of hospital stay (LOS). Methods: For patients with AC, clinical factors and computed tomography features, including our proposed grading system of pericholecystic fat stranding were used for predicting an LOS of ≥7 days in the logistic regression models. Results: Our multivariable model showed age ≥ 65 years (OR: 2.56, p < 0.001), C-reactive protein (CRP) ≥ 2 mg/dL (OR: 1.97, p = 0.013), gamma-glutamyltransferase levels (OR: 2.460, p = 0.001), TG18 grade (OR: 2.89 per grade, p < 0.001), and moderate to severe pericholecystic fat stranding (OR: 2.14, p = 0.012) exhibited prolonged LOS ≥ 7 days. Conclusions: We developed a scoring model, including TG18 grades (score of 1-3 per grade), our grading system of fat stranding (score of 1), CRP (score of 1), and gamma-glutamyltransferase (score of 1), and a cutoff of >3 had highest diagnostic performance.

Dual-energy CT in acute cholecystitis- features predicting culture-positive bile and outcome

PURPOSE

Low mono-energetic CT has been shown to improve visualization of acute abdominal inflammatory processes. We aimed to determine its utility in patients with acute cholecystitis and potential added value in clinical decision making.

METHODS

Sixty-seven consecutive patients with radiological signs of cholecystitis on contrast-enhanced dual-layer CT imaging were retrospectively identified over a four-year period (2/17-8/21). A ranked Likert scale was created for imaging findings present in acute cholecystitis, including gallbladder mucosal integrity and enhancement and pericholecystic liver parenchymal enhancement. These rankings were correlated with laboratory data, followed by sensitivity, specificity, and odds-ratios calculations.

RESULTS

Mucosal integrity and pericholecystic liver enhancement were better seen on low-energetic images by unanimous consensus. Presence of pericholecystic liver enhancement and poorer mucosal wall integrity correlated with positive bile cultures (sensitivity: 93.8 % and 96.9 %, specificity: 37.5 and 50.0 %; odds-ratio: 9.0[1.1-68.1 95 %CI] and 31.0 [2.7-350.7 95 %CI], p = 0.017 and p ≤ 0.001) in patients undergoing cholecystostomy (n = 40/67). Moreover, binary regression modeling showed that the strongest predictor variable for bile culture positivity was the score for pericholecystic liver enhancement (Exp(B) = 0.6, P = 0.022). By contrast, other laboratory markers and other imaging findings (such as GB wall thickness) showed lower sensitivities (76-82 %), specificities (16-21 %) and odds ratios (0.2-4.4) for the prediction of infected bile.

CONCLUSIONS

Pericholecystic liver enhancement and gallbladder wall integrity are better visualized on low-DECT images. These findings also potentially predict bile culture positivity in patients with cholecystitis, which may influence clinical management including the need for intervention.

Traveling gallstones: review of MR imaging and surgical pathology features of gallstone disease and its complications in the gallbladder and beyond

Gallstone-related disease comprises a spectrum of conditions resulting from biliary stone formation, leading to obstruction and inflammatory complications. These can significantly impact patient quality of life and carry high morbidity if not accurately detected. Appropriate imaging is essential for evaluating the extent of gallstone disease and assuring appropriate clinical management. Magnetic Resonance Imaging (MRI) techniques (including Magnetic Resonance Cholangiopancreatography (MRCP) are increasingly used for diagnosis of gallstone disease and its complications and provide high contrast resolution and facilitate tissue-level assessment of gallstone disease processes. In this review we seek to delve deep into the spectrum of MR imaging in diagnose of gallstone-related disease within the gallbladder and complications related to migration of the gallstones to the gall bladder neck or cystic duct, common hepatic duct or bile duct (choledocholithiasis) and beyond, including gallstone pancreatitis, gallstone ileus, Bouveret syndrome, and dropped gallstones, by offering key examples from our practice. Furthermore, we will specifically highlight the crucial role of MRI and MRCP for enhancing diagnostic accuracy and improving patient outcomes in gallstone-related disease and showcase relevant surgical pathology specimens of various gallstone related complications.

A meta-analysis of the performance of ultrasound, hepatobiliary scintigraphy, CT and MRI in the diagnosis of acute cholecystitis

PURPOSE

To evaluate the recently reported relative diagnostic accuracy of US, CT, MRI, and cholescintigraphy for diagnosing acute cholecystitis.

METHODS

2 radiologists independently performed systematic electronic searches for articles published between 2000 and 2021 and applied inclusion/exclusion criteria. 2 different radiologists extracted data from the articles and scored each with a methodological quality tool. Pooled estimates of sensitivity and specificity were calculated with a bivariate linear mixed model. A second analysis made head-to-head comparisons (US vs. CT, US vs. cholescintigraphy). Factors were also analyzed for potential confounding effects on diagnostic accuracy.

RESULTS

Of 6121 initial titles, 22 were included. The prevalence of cholecystitis varied widely across studies (9.4-98%). Pooled sensitivity and specificity estimates were 69% (confidence limit [CL] 62-76%) and 79% (CL 71-86%) for US, 91% (CL 86-94%) and 63% (CL 51-74%) for cholescintigraphy, 78% (CL 69-84%) and 81% (CL 71-88%) for CT, and 91% (CL 78-97%) and 93% (CL 70-99%) for MRI. Regarding head-to-head comparisons, the sensitivity of CT (87.6%, CL 70-96%) was significantly higher than US (66.8%, CL 43-84%), while specificities (81.7% with CL 54-95% for US, 91.9% with CL 67-99% for CT) were similar. The sensitivity of cholescintigraphy (87.4%, CL 76-94%) was significantly greater than US (61.6%, CL 44-77%), while the specificity of US (82%, CL 65-92%) was significantly higher than cholescintigraphy (68%, CL 47-84%).

CONCLUSION

Recent data suggests that CT may have a higher sensitivity than US for diagnosing acute cholecystitis, with similar specificity. Cholescintigraphy remains a highly sensitive modality with lower specificity than previously reported. MRI remains under studied, but with promising results.

Value of high frame rate contrast enhanced ultrasound in gallbladder wall thickening in non-acute setting

BACKGROUND

Ultrasound (US) has been widely used in screening and differential diagnosis of gallbladder wall thickening (GWT). However, the sensitivity and specificity for diagnosing wall-thickening type gallbladder cancer are limited, leading to delayed treatment or overtreatment. We aim to explore the value of high frame rate contrast enhanced ultrasound (H-CEUS) in distinguishing wall-thickening type gallbladder cancer (malignant) from GWT mimicking malignancy (benign).

METHODS

This retrospective study enrolled consecutive patients with non-acute GWT who underwent US and H-CEUS examination before cholecystectomy. Clinical information, US image and H-CEUS image characteristics between malignant and benign GWT were compared. The independent risk factors for malignant GWT on H-CEUS images were selected by multivariate logistic regression analysis. The diagnostic performance of H-CEUS in determining malignant GWT was compared with that of the gallbladder reporting and data system (GB-RADS) score.

RESULTS

Forty-six patients included 30 benign GWTs and 16 malignant GWTs. Only mural layering and interface with liver on US images were significantly different between malignant and benign GWT (P < 0.05). Differences in enhancement direction, vascular morphology, serous layer continuity, wash-out time and mural layering in the venous phase of GWT on H-CEUS images were significant between malignant and benign GWT (P < 0.05). The sensitivity, specificity and accuracy of H-CEUS based on enhancement direction, vascular morphology and wash-out time in the diagnosis of malignant GWT were 93.75%, 90.00%, and 91.30%, respectively. However, the sensitivity, specificity and accuracy of the GB-RADS score were only 68.75%, 73.33% and 71.74%, respectively. The area under ROC curve (AUC) of H-CEUS was significantly higher than that of the GB-RADS score (AUC = 0.965 vs. 0.756).

CONCLUSIONS

H-CEUS can accurately detect enhancement direction, vascular morphology and wash-out time of GWT, with a higher diagnostic performance than the GB-RADS score in determining wall-thickening type gallbladder cancer. This study provides a novel imaging means with high accuracy for the diagnosis of wall-thickening type gallbladder cancer, thus may be better avoiding delayed treatment or overtreatment.

Biliary Disease in a Tertiary Care Hospital: A Review of Clinical and Radiological Burden

Introduction Gallbladder disease accounts for a significant percentage of surgical admissions per year. A review of these cases was done to assess their hospital impact with an evaluation of the efficacy of radiological modalities in terms of evaluation, ideal use, and clinical application. Therefore, this study aims to review the demographics of the disease, the diagnostic yield of radiological modalities, and the overall outcome in regards to the hospital policies and medical services provided in hopes of achieving suitable clinical pathways, increasing the efficiency of gallbladder disease assessment, and limiting unwarranted investigations. Methods This is a single-center, retrospective study that included all the surgical emergency admissions from January 1st to December 31st 2018, in the Salmaniya Medical Complex, Kingdom of Bahrain. A total sample of 163 emergency admissions (cases) was selected from those aged 14 and older with documented biliary stones or biliary-related disease. A review of radiological modalities for diagnosis included plain radiographs (AXR, CXR), US abdomen, CT scans, and MRCP/MRI, which were then correlated with histopathological findings confirming the presence of gallstone disease. In addition to evaluating readmissions and emergency visits in terms of hospital burden. Results One hundred and sixty-three (10.44%) of 1,562 surgical admission cases in 2018 were diagnosed with biliary tree disease (76 males, 87 females). A total of 419 different radiological investigations were requested in 161 of the cases evaluated: 53.7% of plain radiographs (AXR, CXR), 33.2% of US abdomen, 11.9% of CT scan, and 1.2% of MRCP/MRI. Ultrasound showed a sensitivity of 48.72% and a specificity of 100%, while CT scan sensitivity was 57.14% and a specificity of 100% when it came to detecting gallstones and gallbladder-related disease. Plain radiographs add no direct benefit to diagnosing biliary disease.  Conclusion Gallbladder disease is very prevalent with a wide array of disease entities, requiring radiological assistance in diagnosis. Ultrasound is the ideal modality for the diagnosis of biliary disease due to its ease of use and availability; it has high sensitivity and specificity, and it can be complemented by other modalities such as CT scans and MRCP/MRI when it comes to assessing for complications. On the other hand, plain radiographs have no significant value in the detection of gallbladder-related disease, and their utilization should be limited to emergency cases with high clinical suspicion.

Diagnostic performance of ultrasound in acute cholecystitis: a systematic review and meta-analysis

BACKGROUND

An updated overview of ultrasound (US) for diagnosis of acute cholecystitis (AC) remains lacking. This systematic review was conducted to evaluate the diagnostic performance of US for AC.

METHODS

A systematic review was conducted following PRISMA guidelines. We meticulously screened articles from MEDLINE, Embase, and the Cochrane Library, spanning from inception to August 2023. We employed the search strategy combining the keywords "bedside US", "emergency US" or "point-of-care US" with "AC". Two reviewers independently screened the titles and abstracts of the retrieved articles to identify suitable studies. The inclusion criteria encompassed articles investigating the diagnostic performance of US for AC. Data regarding diagnostic performance, sonographers, and sonographic findings including the presence of gallstone, gallbladder (GB) wall thickness, peri-GB fluid, or sonographic Murphy sign were extracted, and a meta-analysis was executed. Case reports, editorials, and review articles were excluded, as well as studies focused on acalculous cholecystitis. The study quality was assessed with the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool.

RESULTS

Forty studies with 8,652 patients were included. The majority of studies had a low risk of bias and applicability concerns. US had a pooled sensitivity of 71% (95% CI, 69-72%), a specificity of 85% (95% CI, 84-86%), and an accuracy of 0.83 (95% CI, 0.82-0.83) for the diagnosis of AC. The pooled sensitivity and specificity were 71% (95% CI, 67-74%) and 92% (95% CI, 90-93%) performed by emergency physicians (EPs), 79% (95% CI, 71-85%) and 76% (95% CI, 69-81%) performed by surgeons, and 68% (95% CI 66-71%) and 87% (95% CI, 86-88%) performed by radiologists, respectively. There were no statistically significant differences among the three groups.

CONCLUSION

US is a good imaging modality for the diagnosis of AC. EP-performed US has a similar diagnostic performance to radiologist-performed US. Further investigations would be needed to investigate the impact of US on expediting the management process and improving patient-centered outcomes.

Accuracy of Ultrasound and Computed Tomography in Diagnosing Acute Cholecystitis Patients in a Tertiary Care Center in Saudi Arabia

Background Acute cholecystitis (AC) is a gallbladder inflammatory disease often associated with gallbladder stones. It accounts for up to 5% of emergency department visits. The majority of patients present with pain in the right upper quadrant, Murphy's sign, and fever. Furthermore, Saudi Arabia has been noted to have a significant prevalence of AC. According to the 2018 Tokyo Guidelines, imaging is an essential element, combined with local and systemic evidence of inflammation, for a confirmed diagnosis of AC. The definitive therapy is conducted surgically by cholecystectomy either urgently or electively. However, there are insufficient studies that focus on the accuracy of imaging in diagnosing AC patients in Saudi Arabia. Objective The aim of this study is to assess the accuracy of ultrasound (US) versus computed tomography (CT) in diagnosing AC patients at King Abdulaziz University Hospital (KAUH), Jeddah, Saudi Arabia. Methods and material A retrospective record review was conducted at KAUH during the period of June to July 2022. The study included 192 patients diagnosed with AC in the emergency department or outpatient department by US or CT or both and confirmed by laparoscopic cholecystectomy and histopathology between 2016 and 2022. Results The most common modality used was US (79.7%), followed by both US and contrast CT (10.9%). For CT, sensitivity was 81.3%, specificity was 62.5%, positive predictive value (PPV) was 59.1%, and negative predictive value (NPV) was 83.3%. For US, sensitivity was 37.9%, specificity was 81.7%, PPV was 50%, and NPV was 73.1%. A significant relationship was observed between both genders and high use of US (P = 0.0001). Conclusion We found that CT is more sensitive than US, while US is more specific in diagnosing AC.

Sonographic Assessment of Acute Versus Chronic Cholecystitis: An Ultrasound Probability Stratification Model

OBJECTIVES

What sonographic variables are most predictive for acute cholecystitis? What variables differentiate acute and chronic cholecystitis?

METHODS

The surgical pathology database was reviewed to identify adult patients who underwent cholecystectomy for cholecystitis and had a preceding ultrasound of the right upper quadrant within 7 days. A total of 236 patients were included in the study. A comprehensive imaging review was performed to assess for gallstones, gallbladder wall thickening, gallbladder distension, pericholecystic fluid, gallstone mobility, the sonographic Murphy's sign, mural hyperemia, and the common hepatic artery peak systolic velocity.

RESULTS

Of 236 patients with a cholecystectomy, 119 had acute cholecystitis and 117 had chronic cholecystitis on surgical pathology. Statistical models were created for prediction. The simple model consists of three sonographic variables and has a sensitivity of 60% and specificity of 83% in predicting acute versus chronic cholecystitis. The most predictive variables for acute cholecystitis were elevated common hepatic artery peak systolic velocity, gallbladder distension, and gallbladder mural abnormalities. If a patient had all three of these findings on their preoperative ultrasound, the patient had a 96% chance of having acute cholecystitis. Two of these variables gave a 73-93% chance of having acute cholecystitis. One of the three variables gave a 40-76% chance of having acute cholecystitis. If the patient had 0 of 3 of the predictor variables, there was a 29% chance of having acute cholecystitis.

CONCLUSIONS

Gallbladder distension, gallbladder mural abnormalities, and elevated common hepatic artery peak systolic velocity are the most important sonographic variables in predicting acute versus chronic cholecystitis.

ACR Appropriateness Criteria® Right Upper Quadrant Pain: 2022 Update

Acute right upper quadrant pain is one of the most common presenting symptoms in hospital emergency departments, as well as outpatient settings. Although gallstone-related acute cholecystitis is a leading consideration in diagnosis, a myriad of extrabiliary sources including hepatic, pancreatic, gastroduodenal, and musculoskeletal should also be considered. This document focuses on the diagnostic accuracy of imaging studies performed specifically to evaluate acute right upper quadrant pain, with biliary etiologies including acute cholecystitis and its complications being the most common. An additional consideration of extrabiliary sources such as acute pancreatitis, peptic ulcer disease, ascending cholangitis, liver abscess, hepatitis, and painful liver neoplasms remain a diagnostic consideration in the right clinical setting. The use of radiographs, ultrasound, nuclear medicine, CT, and MRI for these indications are discussed. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Rapid detection of cholecystitis by serum fluorescence spectroscopy combined with machine learning

While cholecystitis is a critical public health problem, the conventional diagnostic methods for its detection are time consuming, expensive and insufficiently sensitive. This study examined the possibility of using serum fluorescence spectroscopy and machine learning for the rapid and accurate identification of patients with cholecystitis. Significant differences were observed between the fluorescence spectral intensities of the serum of cholecystitis patients (n = 74) serum and those of healthy subjects (n = 71) at 455, 480, 485, 515, 625 and 690 nm. The ratios of characteristic fluorescence spectral peak intensities were first calculated, and principal component analysis (PCA)-linear discriminant analysis (LDA) and PCA-support vector machine (SVM) classification models were then constructed using the ratios as variables. Compared with the PCA-LDA model, the PCA-SVM model displayed better diagnostic performance in differentiating cholecystitis patients from healthy subjects, with an overall accuracy of 96.55%. This exploratory study showed that serum fluorescence spectroscopy combined with the PCA-SVM algorithm has significant potential for the development of a rapid cholecystitis screening method.

Imaging acute cholecystitis, one test is enough

BACKGROUND

Patients with right upper quadrant pain are often imaged using multiple modalities with no established gold standard. A single imaging study should provide adequate information for diagnosis.

METHODS

A multicenter study of patients with acute cholecystitis was queried for patients who underwent multiple imaging studies on admission. Parameters were compared across studies including wall thickness (WT), common bile duct diameter (CBDD), pericholecystic fluid and signs of inflammation. Cutoff for abnormal values were 3 mm for WT and 6 mm for CBDD. Parameters were compared using chi-square tests and Intra-class correlation coefficients (ICC).

RESULTS

Of 861 patients with acute cholecystitis, 759 had ultrasounds, 353 had CT and 74 had MRIs. There was excellent agreement for wall thickness (ICC = 0.733) and bile duct diameter (ICC = 0.848) between imaging studies. Differences between wall thickness and bile duct diameters were small with nearly all <1 mm. Large differences (>2 mm) were rare (<5%) for WT and CBDD.

CONCLUSIONS

Imaging studies in acute cholecystitis generate equivalent results for typically measured parameters.

The use of additional imaging studies after biliary point-of-care ultrasound in the emergency department

PURPOSE

We sought to determine the test characteristics of biliary point-of-care ultrasound (POCUS) and to assess the usefulness of obtaining radiology ultrasound (RUS) or cholescintigraphy (HIDA) after biliary POCUS.

METHODS

We conducted a retrospective review of emergency department patients who underwent biliary POCUS between May 4, 2018 and November 28, 2021. To be included, patients had to have at least one of the following confirmatory evaluations (considered in this order): surgery, HIDA, RUS, or abdominal CT scan. When a discrepancy existed between the POCUS and the RUS or HIDA, they were compared to a higher criterion standard (if available).

RESULTS

Using 348 patients who had a confirmatory evaluation after biliary POCUS, we found the sensitivity and specificity of biliary POCUS for gallstones to be 97.0% (95% CI 92.6 to 99.2%) and 99.5% (95% CI 97.3 to 100%), respectively. For cholecystitis, the sensitivity and specificity were 83.8% (95% CI 72.9 to 91.6%) and 98.6% (95% CI 96.4 to 99.6%), respectively. RUS and POCUS were concordant in 72 (81.8%) of 88 cases in which the patient had both studies while HIDA and POCUS were concordant in 24 (70.6%) of 34 cases. POCUS was deemed correct in at least 50% of discrepant cases with RUS and at least 30% of discrepant cases with HIDA.

CONCLUSION

Biliary POCUS has excellent sensitivity and specificity for cholelithiasis; it has lower sensitivity for cholecystitis, but the specificity remains high. Performing a confirmatory RUS or cholescintigraphy after a positive biliary POCUS adds little value, but additional imaging may be useful when POCUS is negative for cholecystitis.

What's new in the hot gallbladder: the evolving radiologic diagnosis and management of acute cholecystitis

Acute cholecystitis (AC) is a common condition and its incidence is rising. New technologies have advanced the imaging diagnosis of AC, providing more structural and functional information as well as allowing the radiologist to distinguish AC from mimics and identify complications from both the disease and its management. Dual energy CT aids in detecting gallstones and gallbladder wall enhancement, which helps to diagnose AC and identify its complications. Similarly, contrast-enhanced and non-contrast perfusion ultrasound techniques improve detection of abnormal gallbladder wall enhancement. Advances in MR imaging including hepatobiliary contrast agents aid in characterizing post-cholecystectomy complications such as bile leaks. Newer interventional techniques have also expanded the suite of options for minimally invasive management. Lumen apposing metal stents provide more options for conservative treatment in non-surgical candidates and are compared to a standard percutaneous cholecystostomy. Radiologists should be familiar with these advanced imaging methods and intervention techniques and the value they can bring to the diagnosis and management of AC.

The gallbladder: what's new in 2022?

This review focuses mainly on the imaging diagnosis, treatment, and complications of acute cholecystitis which is the most common benign disease of the gallbladder. The American College of Radiology appropriateness criteria for the imaging evaluation of patients with right upper quadrant pain and the Tokyo Guidelines for evaluating patients with acute cholecystitis and acute cholangitis are presented. The recent articles for using US, CT, MR, and HIDA in the evaluation of patients with suspected acute cholecystitis are reviewed in detail. The clinical management and postoperative complications are described. Because gallbladder polyps and adenomyomatosis can mimic gallbladder malignancies and acute cholecystitis, their imaging findings and management are presented. Finally, due the recent literature reporting better results with CT than US in the diagnosis of acute cholecystitis, a suggested approach for imaging patients with right upper quadrant pain and possible acute cholecystitis is presented in an addendum.

Successful Management of Biliary Ascariasis in a High-Endemic Zone and Low-Resource Setting in Ethiopia

Ascariasis lumbricoides is a roundworm that causes one of the most common soil-transmitted helminth infections worldwide. Ascariasis is typically found in the jejunum and transmitted through the intake of Ascaris lumbricoides eggs through food and water. Initially, ascariasis can cause pulmonary symptoms during the first 6-8 weeks of ingestion and can progress to serious complications of intestinal obstruction and hepatobiliary manifestations. Biliary ascariasis is a complication of ascariasis migration from the jejunum to the hepatobiliary tree and can present with a variety of symptoms ranging from biliary colic to more serious features such as acute cholangitis. Though the mortality rate is low, limited resources for management can make it challenging to manage.

Focusing in on gallbladder disease. Do current imaging modalities accurately depict the severity of final pathology?

BACKGROUND

Accuracy of imaging modalities for gallbladder disease(GBD) remains questionable. We hypothesize ultrasonography(US), computed tomography(CT), and magnetic resonance imaging(MRI) poorly correlate with final pathologic analysis.

METHODS

This was a retrospective review of all patients who underwent cholecystectomy at our institution. Primary outcome was agreement between US, CT, and MRI, and final pathology report of the gallbladder. Cohen's Kappa statistic was used to describe the level of agreement (0 = agreement equivalent to chance, 0.1-0.2 = slight agreement, 0.21-0.40 = minimal/fair agreement, 0.41-0.60 = moderate agreement, 0.61-0.80 = substantial agreement, 0.81-0.99 = near perfect agreement, 1 = perfect agreement). Significance was set at p < 0.05.

RESULTS

1107 patients were enrolled. Average age was 48.6(±17.6); 64.2% were female. There was minimal agreement between the three imaging modalities and final pathology (US = 0.363; CT = 0.223; MRI = 0.351;p < 0.001).

CONCLUSION

Poor agreement exists between imaging modalities and final pathology report for GBD. Urgent surgical intervention for patients presenting with symptoms of GBD should be considered, despite imaging results.

Prevalence and Factors Associated With Post-Cholecystectomy Syndrome in Saudi Arabia

OBJECTIVES

Post-cholecystectomy syndrome (PCS) refers to the continuation or recurrence of biliary colic and any other gastrointestinal symptoms present prior to cholecystectomy. Given that PCS is rare and underestimated in Saudi Arabia, this study aimed to determine the prevalence of PCS among Saudis.

METHODS

This cross-sectional study included randomly gathered subjects who self-administered the validated European Organization for Research and Treatment of Cancer QLQ-C30 questionnaire from September 6 to October 7, 2022.

RESULTS

A total of 518 participants who underwent cholecystectomies were included; most were female (73.6%), 153 (29.5%) were 19 to 25 years old, and the vast majority were Saudi Arabian (91.1%). The average preoperative weight was 71 ± 20.7 kg (range 20 to 258), and the mean current weight was 69 ± 19.4 kg (range 30 to 257). About 137 (26.4%) had a chronic disease, most frequently hypertension (37.2%). In the past week, most participants experienced some trouble doing strenuous activities (42.9%), slight pain (37.6%), fatigue (32.2%), insomnia (37.5%), and weakness (38.2%). There were no significant associations between age, nationality, or residence with the QLQ-C30 score (P-value = 0.152, 0.262, 0.071, respectively). A significant association was observed between gender and QLQ-C30 score (P-value < 0.001), with females scoring higher than their male counterparts. Females also reported having a higher quality of life than males.

CONCLUSIONS

The prevalence of PCS was higher than reported elsewhere.

Potential Risk of Misjudgment in the Decision-making Process Based on the 2018 Tokyo Guidelines in Older Patients with Acute Cholecystitis

Objective The 2018 Tokyo Guidelines (TG18) were published to facilitate the decision-making processes (DMP), including the diagnosis and operation of acute cholecystitis (AC). However, only a few guidelines consider older adults. This study evaluated the DMP based on the TG18, focusing on older patients with AC. Methods This was a single-armed, single-center retrospective study. The primary outcome measure was the "undiagnosable" AC rate, and the secondary outcome measure was the degree of concordance of "unfit for surgery" decisions. Patients Two hundred and nine patients with AC. Results Sixty (28.7%) of 209 patients with AC were "undiagnosable" on admission based on the TG18 criteria. The numbers and rate of "undiagnosable" AC in patients ≤59, 60-79, and ≥80 years old were 4 (10.0%), 20 (24.4%), and 36 (41.4%), respectively (P<0.001). The multiple logistic regression analysis following the univariate analysis revealed that age >73 years old was the most significant risk factor for undiagnosable AC (P=0.006, odds ratio [OR]: 3.06, 95% confidence interval [CI]: 1.38-6.81). Female sex (P=0.033, OR: 2.09, 95% CI: 1.06-4.09) and severe AC (P=0.049, OR: 2.97, 95% CI: 1.01-8.76) were also significant risk factors for undiagnosable AC. The number of cases unfit for surgery based on the Charlson Comorbidity Index and American Society of Anesthesiologists physical status was 90 (43.1%) and 75 (35.9%), respectively. The κ value between these 2 indicators revealed a minimal concordance of 0.33 (95% CI: 0.20-0.47). Conclusion The DMP based on the TG18 potentially harbors a misjudgment risk, especially in older patients with AC (UMIN000047715).

Maximum Diameter of the Gallbladder Determined Presurgically Using Computed Tomography as a Risk Factor for Difficult Emergency Laparoscopic Cholecystectomy in Patients With Mild to Moderate Acute Cholecystitis

BACKGROUND

Early or emergency laparoscopic cholecystectomy (LC) was recommended in the 2018 Tokyo Guidelines for patients with mild to moderate acute cholecystitis (AC). Although surgical difficulty is frequently encountered during these surgeries, risk factors for predicting surgical difficulties have not been fully investigated, especially based on computed tomography (CT) findings.

MATERIALS AND METHODS

We investigated 72 patients who underwent emergency LC with mild (n=45) to moderate (n=27) AC. Patients who previously underwent presurgical percutaneous or endoscopic biliary drainage were excluded from this study. Difficult LC was defined using any of the following surgical factors: surgical duration ≥180 minutes, blood loss ≥300 g, or a conversion to open cholecystectomy. Subsequently, several presurgical clinical factors were analyzed, including sex, age at surgery, experience of the surgeon, interval between symptom onset and surgery, body mass index, diabetes history, presurgical white blood cell count, and C-reactive protein level. Moreover, stones in the cystic duct or perigallblader fluid and the maximum thickness and diameter of the gallbladders were evaluated via presurgical CT. Finally, logistic regression analysis was performed to compare the relationship between surgical difficulty and each clinical factor.

RESULTS

The average age at surgery of the included patients was 60.3 (range: 25 to 88 y), surgical duration was 112.2 (range: 29 to 296 min), and surgical blood loss was 55.2 (range: 0 to 530 g). Furthermore, 4 (5.6%) had to undergo open cholecystectomy, whereas postsurgical complications occurred in 5 (6.9%) patients. In addition, the mean postsurgical admission duration was 7 (range: 3 to 63 d). Thus, 12 patients experienced difficult LC, whereas 60 experienced nondifficult LC. Of the evaluated clinical factors, patients who experienced difficult LC showed higher presurgical C-reactive protein levels (10.78 vs. 6.76 mg/dL, P=0.01) and wider gallbladder diameters (48.4 vs. 41.8 mm, P<0.01) than those who experienced nondifficult LC. By univariate logistic regression analysis, results also showed that patients with a maximum gallbladder diameter had a higher risk of experiencing difficulty during emergency LC (P=0.02). Moreover, the gallbladder diameter's cutoff value was 43 mm after the receiver operating characteristic curve analysis.

CONCLUSIONS

In patients with mild to moderate AC, emergency LC can safely be performed. However, performing LC might be technically difficult in patients with AC after the identification of severe gallbladder swelling during presurgical CT.

Guidelines for Reasonable and Appropriate Care in the Emergency Department 2 (GRACE-2): Low-risk, recurrent abdominal pain in the emergency department

This second Guideline for Reasonable and Appropriate Care in the Emergency Department (GRACE-2) from the Society for Academic Emergency Medicine is on the topic "low-risk, recurrent abdominal pain in the emergency department." The multidisciplinary guideline panel applied the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to assess the certainty of evidence and strength of recommendations regarding four priority questions for adult emergency department patients with low-risk, recurrent, undifferentiated abdominal pain. The intended population includes adults with multiple similar presentations of abdominal signs and symptoms recurring over a period of months or years. The panel reached the following recommendations: (1) if a prior negative computed tomography of the abdomen and pelvis (CTAP) has been performed within 12 months, there is insufficient evidence to accurately identify populations in whom repeat CTAP imaging can be safely avoided or routinely recommended; (2) if CTAP with IV contrast is negative, we suggest against ultrasound unless there is concern for pelvic or biliary pathology; (3) we suggest that screening for depression and/or anxiety may be performed during the ED evaluation; and (4) we suggest an opioid-minimizing strategy for pain control. EXECUTIVE SUMMARY: The GRACE-2 writing group developed clinically relevant questions to address the care of adult patients with low-risk, recurrent, previously undifferentiated abdominal pain in the emergency department (ED). Four patient-intervention-comparison-outcome-time (PICOT) questions were developed by consensus of the writing group, who performed a systematic review of the literature and then synthesized direct and indirect evidence to formulate recommendations, following GRADE methodology. The writing group found that despite the commonality and relevance of these questions in emergency care, the quantity and quality of evidence were very limited, and even fundamental definitions of the population and outcomes of interest are lacking. Future research opportunities include developing precise and clinically relevant definitions of low-risk, recurrent, undifferentiated abdominal pain and determining the scope of the existing populations in terms of annual national ED visits for this complaint, costs of care, and patient and provider preferences.

Diagnostic value of endoscopic retrograde cholangiopancreatography and therapeutic value of endoscopic sphincterotomy in dogs with suspected hepatobiliary disorders

Background

Conventional diagnostic methods have some limitations in diagnosing specific causes of canine hepatobiliary disorders. In the evaluation of the hepatobiliary system in dogs, ultrasonography (US) is the first imaging method of choice. Nonetheless, endoscopic retrograde cholangiopancreatography (ERCP) has also been proven to be a practicable technique for evaluating canine hepatobiliary (endoscopic retrograde cholangiography, ERC) and pancreatic duct (endoscopic retrograde pancreatography, ERP) disorders, providing additional therapeutic options by sphincterotomy (EST). To date, the efficacy and safety of diagnostic and therapeutic ERCP has not been evaluated in veterinary medicine literature. The present study sought to report complications and outcomes of dogs undergoing ERCP and EST, and to assess the usefulness of diagnostic ERCP by comparing the findings of US, ERCP and histopathological findings in liver and pancreas.

Results

This retrospective case series comprises data collected from 15 dogs that underwent successful ERC/ERCP. Nine dogs underwent EST following ERC. US and ERC were best in agreement when assessing the common bile duct. In case of disagreement between the modalities, the ERC findings of the ductal structures were in line with the available pathology findings more often than the US findings, whereas the opposite was noted for the gallbladder. The technical success rates were 88.2% for ERC, 66.7% for ERP, and 81.8% for EST, with no major complications during or immediately after the procedure. Immediate bile flow after EST was recorded in 7/9 dogs but only four showed coinciding clinical and laboratory improvement and four dogs were euthanized within 1-6 days after EST.

Conclusions

US remains a valuable initial diagnostic imaging method for hepatobiliary disorders and allows good assessment of the gallbladder. ERC can serve as a complementary procedure for diagnostic assessment of the hepatobiliary duct disorders. However, in order to improve the outcomes of EST, careful selection of patients for the procedure would require more advanced diagnostic imaging of the hepatobiliary area.

Use of Gallbladder Width Measurement by Computed Tomography in the Diagnosis of Acute Cholecystitis

This study aimed to evaluate the diagnostic value of gallbladder width measurement with computed tomography (CT) in patients with acute cholecystitis. This retrospective case−control study was conducted between March 2016 and March 2020 at a tertiary emergency department. Of 310 patients, 254 patients with acute cholecystitis confirmed by surgery were compared with 254 patients diagnosed with other diseases (controls). In the acute cholecystitis group, the number of older patients with underlying illnesses was much higher (64% of men). Upon CT, the median (interquartile range [IQR]) gallbladder width was significantly longer in patients with acute cholecystitis (2.26 [1.82−2.78] cm vs. 3.73 [3.32−4.16] cm, p < 0.001). The optimal cut-off value of gallbladder width for differentiating acute cholecystitis was 3.12 cm, showing a sensitivity of 88% and specificity of 86%. In a multivariable analysis using a logistic regression model for diagnosing acute cholecystitis with CT findings (gallbladder width, length, stone, wall thickening, and pericholecystic fluid), a gallbladder width of ≥3.12 cm was significantly meaningful, even when adjusting for other variables (odds ratio 37.9; p < 0.001). Therefore, an increase in gallbladder width (≥3.12 cm) measured with CT can be a simple and sensitive diagnostic sign of acute cholecystitis, supporting the underlying pathophysiology of bile outflow obstruction.

Hotter Than It Looks: A Retrospective Review of Patients With Cholecystitis and With Negative Imaging

INTRODUCTION

Ultrasound is the gold standard for workup of cholecystitis in the emergency department, and findings heavily influence clinical decision-making. Patients with negative imaging for acute cholecystitis may be inappropriately sent home. The purpose of our study was to review the pathology and outcomes of patients presenting with biliary pain and negative ultrasound findings of acute cholecystitis.

MATERIALS AND METHODS

Emergency department patients who underwent laparoscopic cholecystectomy between January 2015 and February 2019 were reviewed retrospectively. Only patients with negative or equivocal imaging were included. The primary outcome was the incidence of cholecystitis on final pathology.

RESULTS

Two hundred fifty-seven patients underwent laparoscopic cholecystectomy. Pathology demonstrated cholecystitis in 84% of patients. Only 15% of patients had cholelithiasis without cholecystitis on pathology. The incidence of cholecystitis was similar in negative and equivocal imaging groups (84% versus 83%; P = 0.960). The median time from admission to the operating room was 12.1 h (interquartile range 7.1-18.3 h), and hospital length of stay was 1.2 d (interquartile range 0.8-1.7 d).

CONCLUSIONS

This study found that patients with negative or equivocal imaging had cholecystitis on pathology. On review of patient outcomes, those patients who underwent surgical intervention had a low rate of complications and short hospital stay.

Grayscale ultrasonography findings for characterization of gallbladder wall thickening in non-acute setting: a systematic review and meta-analysis

BACKGROUND

The accurate characterization of gallbladder wall thickening (GWT) into benign or malignant on ultrasound (US) is a significant challenge.

METHODS

We searched the MEDLINE and EMBASE databases for studies reporting two-dimensional grayscale US in benign and malignant GWT. The pooled prevalence was calculated using a generalized linear mixed method with a random-effects model. The pooled sensitivity and specificity were calculated using a bivariate random-effects model.

RESULTS

Of the 7309 studies screened by titles, 73 studies with 18,008 patients were included. The most common findings in xanthogranulomatous cholecystitis (XGC) were lack of wall disruption and intramural hypoechoic nodules while adenomyomatosis (ADM) was frequently associated with intramural cysts and intramural echogenic foci. Echogenic foci, lack of gallbladder wall disruption, and hypoechoic nodules had a sensitivity of 89%, 77%, and 66% and specificity of 86%, 51%, and 80%, respectively for the diagnosis of benign GWT. Focal thickening and indistinct liver interface had a sensitivity of 75% and 55% and specificity of 64% and 69%, respectively for the diagnosis of malignant GWT.

CONCLUSION

intramural features (echogenic foci, hypoechoic nodules), gallbladder wall disruption, and liver interface are useful US features for the characterization of GWT.

The imaging diagnosis of cholecystitis in the adult ED: a comparative multi-reader, multivariable analysis of CT and US image features

PURPOSE

The purposes of this study are (1) to utilize multivariable logistic regression in order to evaluate which image feature combination is most predictive in the diagnosis of cholecystitis for computed tomography (CT) and ultrasound (US) in adult ED patients and (2) to use these results to compare the accuracy of CT and US.

METHODS

For RUQ pain patients undergoing US and CT at the same visit, multiple image features were evaluated independently by 2 radiologists blinded to additional data. Inter-reader variability was measured with the Kappa statistic. Sonographic Murphy's sign (SMS) information was obtained from original reports. Multivariable logistic regression was utilized to develop optimal predictive models for each modality. For US, models with/without SMS were compared to establish its relative value.

RESULTS

446 patients met inclusion criteria. For CT, the combination of cholelithiasis, short-axis gallbladder diameter > 3 cm, pericholecystic fluid or inflammation, and mural thickening > 3 mm provided the optimal model for both readers. For US, the optimal model included cholelithiasis, short-axis diameter > 3 cm, mural heterogeneity/striation, and sludge/debris for both readers. Kappa = 0.79-0.96 for included image features. For both readers, CT and US models had equivalent diagnostic performances; the SMS did not contribute significantly to US models.

CONCLUSION

For a diagnosis of cholecystitis in the ED, (1) the optimal image feature combination for CT is cholelithiasis, short-axis diameter > 3 cm, pericholecystic fluid or inflammation, mural thickening > 3 mm; and cholelithiasis, short-axis diameter > 3 cm, mural heterogeneity/striation, sludge/debris for US; (2) CT and US have equivalent diagnostic performance; (3) inter-reader reliability is substantial to excellent for utilized image features; (4) the SMS does not affect US model accuracy.

Beyond acute cholecystitis-gallstone-related complications and what the emergency radiologist should know

The purpose of this study is to emphasize the imaging features of complications of gallstones beyond the cystic duct on ultrasound (US), enhanced and nonenhanced computed tomography (CECT and NECT), magnetic resonance imaging (MRI), magnetic resonance cholangiopancreatography (MRCP), and endoscopic retrograde cholangiopancreatography (ERCP). This article includes a brief overview of gallstone imaging and emerging trends in the detection of gallstones. This review article will highlight complications of gallstones, including choledocholithiasis, gallstone pancreatitis, acute cholangitis, Mirizzi syndrome, cholecystobiliary and cholecystoenteric fistulas, and gallstone ileus. Imaging findings and limitations of US, CT, MRI, and ERCP will be discussed. The review article will also briefly discuss the management of each disease. The presence of gallstones beyond the level of the cystic duct can lead to a spectrum of diseases, and emergency radiologists play a critical role in disease management by providing a timely diagnosis. Documenting the location of a gallstone within the common bile duct (CBD) in symptomatic cholelithiasis and the presence of acute interstitial edematous pancreatitis and/or ascending cholangitis plays a pivotal role in disease management. Establishing the presence of ectopic gallstones and biliary-enteric fistulae has a significant role in directing patient management.

CT findings and outcomes of acute cholecystitis: is additional ultrasound necessary?

BACKGROUND

While ultrasound is often the preferred imaging modality for suspected acute cholecystitis (AC), CT is often the first line study when patients are being evaluated for abdominal pain. The diagnostic value of CT in the setting of AC is controversial, given the prevalent use of additional imaging.

PURPOSE

To evaluate the positive predictive value (PPV) of CT for diagnosing acute cholecystitis (AC) when used as a first line imaging study for evaluating abdominal pain and assess if additional imaging with ultrasound studies provides additional clinically useful information.

MATERIALS AND METHODS

Abnormal gallbladder findings in CT imaging studies were queried in a retrospective study over a 25-month period within a large urban health system. Sonographic (US) studies performed within 72 h of the initial CT were also included. Outcomes were determined by surgical pathology, fluid analysis, and clinical outcomes. Cases were stratified by the interpreting radiologist's subjective confidence level of diagnosing AC, and the PPVs were compared between cases using CT without US and cases with both CT and US.

RESULTS

Of the 468 CT studies meeting criteria, 192 were read as concerning for AC. PPV of CT was 44.7% without US and 50.5% when US was positive, which amounted to an insignificant gain (p = 0.41). When subdividing by confidence level, high-confidence positive CTs demonstrated no significant difference without ultrasound (80%) compared to with ultrasound (75%). Less confident reads in CT demonstrated potential gain from ultrasound; in the case of a "probable" CT impression, PPV increased from 45% without US to 90% with a high-confidence ultrasound impression.

CONCLUSION

Based on current practice within a large health system, CT examinations with high suspicion for AC demonstrated little gain from follow-up ultrasound. However, ultrasound may be of benefit when CT interpretations are less confident but still suspicious for AC.

Acute cholecystitis: diagnostic value of dual-energy CT-derived iodine map and low-keV virtual monoenergetic images

PURPOSE

To compare conventional and dual-energy CT (DECT) for the diagnosis of acute cholecystitis and gangrene.

METHODS

Fifty-seven consecutive adult patients with abdominal pain who underwent IV contrast-enhanced abdominal DECT on a dual-layer (dlDECT) or rapid-switching (rsDECT) scanner from September, 2018 to April, 2021 with cholecystectomy and pathology-confirmed cholecystitis were retrospectively reviewed, and compared with 57 consecutive adult patients without cholecystitis from the same interval scanned with DECT. Images were reviewed independently by two abdominal radiologists with 12 and 16 years of experience in two sessions 4 weeks apart, blinded to clinical data. Initially, only blended reconstructions (simulating conventional single-energy CT images) were reviewed (CT). Subsequently, CT and DECT reconstructions including low-keV virtual monoenergetic images and iodine maps were reviewed. Gallbladder fossa hyperemia, pericholecystic fluid, subjective presence of gangrene, heterogeneous wall enhancement, sloughed membranes, intramural air, abscess, overall impression of the presence of acute cholecystitis, and intramural iodine density were assessed.

RESULTS

Gallbladder fossa hyperemia was detected with increased sensitivity on DECT (R1, 61.4%; R2, 75.4%) vs. CT (R1, 22.8%; R2, 15.8%). DECT showed increased sensitivity for gangrene (R1, 24.6%; R2, 38.6%) vs. CT (R1, 5.3%; R2, 14%), heterogeneous wall enhancement (DECT: R1, 33.3%; R2, 63.2% vs. CT: R1, 7%; R2, 31.6%), and cholecystitis (DECT: R1, 86%; R2, 89.5% vs. CT: R1, 77.2%; R2, 70.2%). In addition, DECT was more sensitive for the detection of acute cholecystitis (R1, 86%; R2, 89.5%) vs. CT (R1, 77.2%; R2, 70.2%). Iodine density threshold of 1.2 mg/ml, 0.8 mg/mL, and 0.5 mg/mL showed specificity for gangrenous cholecystitis of 78.26%, 86.96%, and 95.65%, respectively, using the rsDECT platform.

CONCLUSION

DECT showed improved sensitivity compared to conventional CT for detection of acute cholecystitis. Iodine density measurements may be helpful to diagnose gangrene.

Synchronous acute sub-serosal appendicitis and cholecystitis, in a patient with a long standing small bowel neuroendocrine tumor

We report the case of a 62-year-old retired man with a long-standing small bowel neuroendocrine tumour. He presented with right-sided abdominal pain associated with nausea and vomiting. Radiographic imaging confirmed acute appendicitis and cholecystitis. We performed a synchronous laparoscopic appendectomy and cholecystectomy in the same setting. Histopathological examination of specimens confirmed the preoperative diagnoses in both organs. Our patient recovered uneventfully. The postoperative management plan focused on continuation of the follow-up for the small bowel neuroendocrine tumour. The synchronicity of both acute cholecystitis and appendicitis is extremely uncommon. We believe that our case report is the first of its kind with synchronous inflammation of the gallbladder and appendix in a patient with neuroendocrine tumour. In this report, we aim to provide insights on managing such a condition in the background of other intra-abdominal tumours.

Cystic artery velocity as a predictor of acute cholecystitis

PURPOSE

To evaluate angle-corrected peak systolic cystic artery velocity (CAv) as a predictor of acute cholecystitis among patients presenting to the emergency department (ED) with right upper quadrant (RUQ) pain.

METHODS

In this IRB-approved and retrospective study, CAv was evaluated in 73 patients, 43 who underwent definitive treatment with cholecystectomy or percutaneous cholecystostomy and 30 control patients without clinical suspicion for cholecystitis. In addition to CAv, the following were reviewed by 3 radiologists: CBD diameter, cholelithiasis, impacted stone in the neck, sludge, gallbladder wall thickness > 3 mm, gallbladder transverse dimension ≥ 4 cm, longitudinal dimension ≥ 8 cm, tensile gallbladder fundus sign, pericholecystic fluid, pericholecystic echogenic fat, and sonographic Murphy sign.

RESULTS

Of the 43 patients who underwent definitive treatment, 25 had acute cholecystitis (34%) and 18 (25%) had chronic cholecystitis. Average CAv measurements were 50 ± 16 cm/s (acute), 28 ± 8 cm/s (chronic), and 22 ± 8 cm/s (control; p < 0.0001). In univariate analysis, among patients who underwent definitive therapy, CAv ≥ 40 cm/s, gallbladder wall thickness, stone impaction, GB long dimension ≥ 8 cm, and elevated WBC were associated with acute cholecystitis (p < 0.05). In multivariate analysis, CAv ≥ 40 cm/s was the only statistically significant variable (p = 0.016). CAv ≥ 40 cm/s alone had a PPV of 94.7% and overall accuracy of 81.4% in diagnosing acute cholecystitis.

CONCLUSION

CAv ≥ 40 cm/s is highly associated with acute cholecystitis in patients presenting to the ED with RUQ pain.

Spectral CT of the abdomen: Where are we now?

Spectral CT adds a new dimension to radiological evaluation, beyond assessment of anatomical abnormalities. Spectral data allows for detection of specific materials, improves image quality while at the same time reducing radiation doses and contrast media doses, and decreases the need for follow up evaluation of indeterminate lesions. We review the different acquisition techniques of spectral images, mainly dual-source, rapid kV switching and dual-layer detector, and discuss the main spectral results available. We also discuss the use of spectral imaging in abdominal pathologies, emphasizing the strengths and pitfalls of the technique and its main applications in general and in specific organs.

Imaging of abdominal complications of COVID-19 infection

Coronavirus disease 2019 (COVID-19) is a respiratory syndrome caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) first described in Wuhan, Hubei Province, China in the last months of 2019 and then declared as a pandemic. Typical symptoms are represented by fever, cough, dyspnea and fatigue, but SARS-CoV-2 infection can also cause gastrointestinal symptoms (vomiting, diarrhoea, abdominal pain, loss of appetite) or be totally asymptomatic. As reported in literature, many patients with COVID-19 pneumonia had a secondary abdominal involvement (bowel, pancreas, gallbladder, spleen, liver, kidneys), confirmed by laboratory tests and also by radiological features. Usually the diagnosis of COVID-19 is suspected and then confirmed by real-time reverse-transcription-polymerase chain reaction (RT-PCR), after the examination of the lung bases of patients, admitted to the emergency department with abdominal symptoms and signs, who underwent abdominal-CT. The aim of this review is to describe the typical and atypical abdominal imaging findings in patients with SARS-CoV-2 infection reported since now in literature.

Toward an evidence-based approach for cholangitis diagnosis

BACKGROUND AND AIMS

Despite improvements in imaging and laboratory medicine, consensus criteria for the diagnosis of cholangitis are lacking. Although ERCP is an effective treatment for cholangitis, it should be reserved for those patients with a high probability of the diagnosis, given the morbidity associated with the procedure.

METHODS

A comprehensive literature search of PubMed (from 1898 to present), Web of Science (1900 to July 15, 2019), Embase (1943 to July 15, 2019), and the Cochrane library (1898 to July 15, 2019) was performed to identify studies that reported on diagnostic paradigms and individual diagnostic parameters of cholangitis. This was used to identify domains associated with high probability of cholangitis.

RESULTS

We identified 23 observational studies (10,252 patients) that evaluated the performance of individual and combined criteria for the diagnosis of cholangitis. Traditional paradigms including Charcot's criteria and Ranson's criteria have inadequate sensitivity, and complexity has limited the implementation of the contemporary Tokyo criteria. Furthermore, controlled studies to validate diagnostic criteria for cholangitis are lacking. Existing literature suggests that 4 criteria, summarized by the acronym BILE, identifies those at high risk of cholangitis: Biliary imaging abnormalities or recent intervention, Inflammatory test abnormalities, Liver test abnormalities, and Exclusion of cholecystitis and acute pancreatitis.

CONCLUSIONS

There is a need for cholangitis diagnostic criteria that are supported by controlled validation studies, consistent with contemporary clinical values, and amenable to implementation. The BILE criteria are straightforward but require prospective study of their diagnostic performance and ability to avert unnecessary ERCP.

Disaster Diagnoses in Geriatric Patients with Abdominal Pain

Care of geriatric patients with abdominal pain can pose significant diagnostic and therapeutic challenges to emergency physicians. Older adults rarely present with classic signs, symptoms, and laboratory abnormalities. The incidence of life-threatening emergencies, including abdominal aortic aneurysm, mesenteric ischemia, perforated viscus, and other surgical emergencies, is high. This article explores the evaluation and management of several important causes of abdominal pain in geriatric patients with an emphasis on high-risk presentations.

Barriers to reporting guideline adherence in point-of-care ultrasound research: a cross-sectional survey of authors and journal editors

OBJECTIVE

Although the literature supporting the use of point-of-care ultrasound (POCUS) continues to grow, incomplete reporting of primary diagnostic accuracy studies has previously been identified as a barrier to translating research into practice and to performing unbiased systematic reviews. This study assesses POCUS investigator and journal editor attitudes towards barriers to adhering to the Standards for Reporting of Diagnostic Accuracy Studies (STARD) 2015 guidelines.

DESIGN, SETTING, PARTICIPANTS

Two separate surveys using a 5-point Likert scale were sent to POCUS study investigators and journal editors to assess for knowledge, attitude and behavioural barriers to the complete reporting of POCUS research. Respondents were identified based on a previous study assessing STARD 2015 adherence for POCUS studies published in emergency medicine, anaesthesia and critical care journals. Responses were anonymously linked to STARD 2015 adherence data from the previous study. Written responses were thematically grouped into the following categories: knowledge, attitude and behavioural barriers to quality reporting, or other. Likert response items are reported as median with IQRs.

MAIN OUTCOME MEASURES

The primary outcome was the median Likert score for the investigator and editor surveys assessing knowledge, attitude and behavioural beliefs about barriers to adhering to the STARD 2015 guidelines.

RESULTS

The investigator survey response rate was 18/69 (26%) and the editor response rate was 5/21 (24%). Most investigator respondents were emergency medicine practitioners (13/21, 62%). Two-thirds of investigators were aware of the STARD 2015 guidelines (12/18, 67%) and overall agreed that incomplete reporting limits generalisability and the ability to detect risk of bias (median 4 (4, 5)). Investigators felt that the STARD 2015 guidelines were useful, easy to find and easy to use (median 4 (4, 4.25); median 4 (4, 4.25) and median 4 (3, 4), respectively). There was a shared opinion held by investigators and editors that the peer review process be primarily responsible for ensuring complete research reporting (median 4 (3, 4) and median 4 (3.75, 4), respectively). Three of 18 authors (17%) felt that the English publication language of STARD 2015 was a barrier to adherence.

CONCLUSIONS

Although investigators and editors recognise the importance of completely reported research, reporting quality is still a core issue for POCUS research. The shared opinion held by investigators and editors that the peer review process be primarily responsible for reporting quality is potentially problematic; we view completely reported research as an integral part of the research process that investigators are responsible for, with the peer review process serving as another additional layer of quality control. Endorsement of reporting guidelines by journals, auditing reporting guideline adherence during the peer review process and translation of STARD 2015 guidelines into additional languages may improve reporting completeness for the acute POCUS literature.

TRIAL REGISTRATION NUMBER

Open Science Framework Registry (https://osf.io/5pzxs/).

Prospective validation of the bedside sonographic acute cholecystitis score in emergency department patients

BACKGROUND

Acute cholecystitis can be difficult to diagnose in the emergency department (ED); no single finding can rule in or rule out the disease. A prediction score for the diagnosis of acute cholecystitis for use at the bedside would be of great value to expedite the management of patients presenting with possible acute cholecystitis. The 2013 Tokyo Guidelines is a validated method for the diagnosis of acute cholecystitis but its prognostic capability is limited. The purpose of this study was to prospectively validate the Bedside Sonographic Acute Cholecystitis (SAC) Score utilizing a combination of only historical symptoms, physical exam signs, and point-of-care ultrasound (POCUS) findings for the prediction of the diagnosis of acute cholecystitis in ED patients.

METHOD

This was a prospective observational validation study of the Bedside SAC Score. The study was conducted at two tertiary referral academic centers in Boston, Massachusetts. From April 2016 to March 2019, adult patients (≥18 years old) with suspected acute cholecystitis were enrolled via convenience sampling and underwent a physical exam and a focused biliary POCUS in the ED. Three symptoms and signs (post-prandial symptoms, RUQ tenderness, and Murphy's sign) and two sonographic findings (gallbladder wall thickening and the presence of gallstones) were combined to calculate the Bedside Sonographic Acute Cholecystitis (SAC) Score. The final diagnosis of acute cholecystitis was determined from chart review or patient follow-up up to 30 days after the initial assessment. In patients who underwent operative intervention, surgical pathology was used to confirm the diagnosis of acute cholecystitis. Sensitivity, specificity, PPV and NPV of the Bedside SAC Score were calculated for various cut off points.

RESULTS

153 patients were included in the analysis. Using a previously defined cutoff of ≥ 4, the Bedside SAC Score had a sensitivity of 88.9% (95% CI 73.9%-96.9%), and a specificity of 67.5% (95% CI 58.2%-75.9%). A Bedside SAC Score of < 2 had a sensitivity of 100% (95% CI 90.3%-100%) and specificity of 35% (95% CI 26.5%-44.4%). A Bedside SAC Score of ≥ 7 had a sensitivity of 44.4% (95% CI 27.9%-61.9%) and specificity of 95.7% (95% CI 90.3%-98.6%).

CONCLUSION

A bedside prediction score for the diagnosis of acute cholecystitis would have great utility in the ED. The Bedside SAC Score would be most helpful as a rule out for patients with a low Bedside SAC Score < 2 (sensitivity of 100%) or as a rule in for patients with a high Bedside SAC Score ≥ 7 (specificity of 95.7%). Prospective validation with a larger study is required.

Utility of ultrasound after a negative CT abdomen and pelvis in the emergency department

PURPOSE

The purpose of this study is to assess the utility of an abdominal and/or pelvic ultrasound (US) performed within 24 h after a negative CT of the abdomen and pelvis (CTAP) in the emergency department (ED). The secondary endpoint is to assess whether there is a significant increase in length of stay (LOS) in the ED due to immediate US reimaging.

METHOD

We reviewed the imaging reports of 335 patients over the course of 3 years in our ED who had an US within 24 h after a negative CTAP. We then assessed type of US and whether the US showed any acute findings. We also evaluated LOS in the ED.

RESULTS

Out of 335 patients, there were only three US cases suspicious for acute surgical pathology (3/335 or 0.9%). On 30-day clinical follow-up, only one of the three cases was confirmed as cholecystitis on pathology. The most common non-surgical findings on US not initially reported on CTAP were ovarian cysts (29/83) and gallstones (9/83). Additionally, the LOS for patients who received both a CTAP and US was 119 min longer than patients who only received a CTAP.

CONCLUSION

US abdomen and/or pelvis reimaging within 24 h following a negative CTAP is unlikely to change surgical management in the acute setting. US reimaging can still be useful in diagnosing non-surgical pathology, which could serve to explain the patient's pain. US reimaging after negative CTAP is associated with an average increase in the ED LOS.

Adherence to the Standards for Reporting of Diagnostic Accuracy (STARD) 2015 Guidelines in Acute Point-of-Care Ultrasound Research

IMPORTANCE

Incomplete reporting of diagnostic accuracy research impairs assessment of risk of bias and limits generalizability. Point-of-care ultrasound has become an important diagnostic tool for acute care physicians, but studies assessing its use are of varying methodological quality.

OBJECTIVE

To assess adherence to the Standards for Reporting of Diagnostic Accuracy (STARD) 2015 guidelines in the literature on acute care point-of-care ultrasound.

EVIDENCE REVIEW

MEDLINE was searched to identify diagnostic accuracy studies assessing point-of-care ultrasound published in critical care, emergency medicine, or anesthesia journals from 2016 to 2019. Studies were evaluated for adherence to the STARD 2015 guidelines, with the following variables analyzed: journal, country, STARD citation, STARD-adopting journal, impact factor, patient population, use of supplemental material, and body region. Data analysis was performed in November 2019.

FINDINGS

Seventy-four studies were included in this systematic review for assessment. Overall adherence to STARD was moderate, with 66% (mean [SD], 19.7 [2.9] of 30 items) of STARD items reported. Items pertaining to imaging specifications, patient population, and readers of the index test were frequently reported (>66% of studies). Items pertaining to blinding of readers to clinical data and to the index or reference standard, analysis of heterogeneity, indeterminate and missing data, and time intervals between index and reference test were either moderately (33%-66%) or infrequently (<33%) reported. Studies in STARD-adopting journals (mean [SD], 20.5 [2.9] items in adopting journals vs 18.6 [2.3] items in nonadopting journals; P = .002) and studies citing STARD (mean [SD], 21.3 [0.9] items in citing studies vs 19.5 [2.9] items in nonciting studies; P = .01) reported more items. Variation by country and journal of publication were identified. No differences in STARD adherence were identified by body region imaged (mean [SD], abdominal, 20.0 [2.5] items; head and neck, 17.8 [1.6] items; musculoskeletal, 19.2 [3.1] items; thoracic, 20.2 [2.8] items; and other or procedural, 19.8 [2.7] items; P = .29), study design (mean [SD], prospective, 19.7 [2.9] items; retrospective, 19.7 [1.8] items; P > .99), patient population (mean [SD], pediatric, 20.0 [3.1] items; adult, 20.2 [2.7] items; mixed, 17.9 [1.9] items; P = .09), use of supplementary materials (mean [SD], yes, 19.2 [3.0] items; no, 19.7 [2.8] items; P = .91), or journal impact factor (mean [SD], higher impact factor, 20.3 [3.1] items; lower impact factor, 19.1 [2.4] items; P = .08).

CONCLUSIONS AND RELEVANCE

Overall, the literature on acute care point-of-care ultrasound showed moderate adherence to the STARD 2015 guidelines, with more complete reporting found in studies citing STARD and those published in STARD-adopting journals. This study has established a current baseline for reporting; however, future studies are required to understand barriers to complete reporting and to develop strategies to mitigate them.

Role of Ultrasound and CT in the Workup of Right Upper Quadrant Pain in Adults in the Emergency Department: A Retrospective Review of More Than 2800 Cases

OBJECTIVE. The purpose of this study was to compare ultrasound and CT in the diagnostic evaluation of right upper quadrant pain in adults in the emergency department. MATERIALS AND METHODS. A retrospective review was conducted of adult emergency department encounters for right upper quadrant pain over a 5-year period, excluding those for prior cholecystectomy, current pregnancy, and trauma. Imaging study reports were reviewed for gallbladder and nongallbladder explanations of right upper quadrant pain and were considered positive for cholecystitis when two or more supportive features were present. Encounter outcomes were evaluated on the basis of pathology data and clinical management. RESULTS. Among the encounters, 2859 met the study inclusion criteria, and 18% met the study definition of cholecystitis by pathologic or clinical criteria. The following metrics showed no statistically significant difference between ultrasound and CT, respectively: sensitivity, 61% and 55%; specificity, 91% and 92%; positive predictive value, 63% and 63%; and negative predictive value, 91% and 90%. Both modalities were performed in 20% of encounters. In the subgroup analysis, ultrasound showed an acute nongallbladder abnormality that was missed at a preceding CT examination in only 1 of 238 cases (0.4%). CT showed an acute nongallbladder abnormality missed at a preceding ultrasound examination in 103 of 322 cases (32%). CONCLUSION. CT is noninferior to ultrasound in both ruling in and ruling out the diagnosis of cholecystitis in adult patients undergoing emergency evaluation of right upper quadrant pain and offers the advantage of depicting acute nongallbladder abnormalities.

Nonfetal Imaging During Pregnancy: Acute Abdomen/Pelvis

Abdominal pain is a common occurrence in pregnant women and may have a variety of causes, including those that are specific to pregnancy (eg, round ligament pain in the first trimester) and the wide range of causes of abdominal pain that affect men and women who are not pregnant (eg, appendicitis, acute cholecystitis). Noncontrast magnetic resonance (MR) imaging is increasingly performed to evaluate pregnant women with abdominal pain, either as the first-line test or as a second test following ultrasonography. The imaging appearance of causes of abdominal pain in pregnant women are reviewed with an emphasis on noncontrast MR imaging.

Sonography of Acute Cholecystitis and Its Mimics

Right upper quadrant (RUQ) abdominal pain is a common complaint. Acute cholecystitis (AC) is the primary diagnostic consideration in most adults presenting with acute onset RUQ abdominal pain; however, a variety of other conditions can mimic AC. Abdominal ultrasound (US) receives the highest score for imaging appropriateness for these patients. This article reviews the sonographic findings of uncomplicated and complicated AC and provides practical technical tips. The radiologist should be familiar with conditions that can mimic AC, be able to suggest these alternative diagnoses when findings are present on US, and recommend additional tests or procedures, if needed.