CT findings in acute gangrenous cholecystitis

UIdataGB: Multi-Class ultrasound images dataset for gallbladder disease detection

Artificial Intelligence (AI) allows computers to self-develop decision-making algorithms through huge data analysis. In medical investigations, using computers to automatically diagnose diseases is a promising area of research that could change healthcare strategies worldwide. However, it can be challenging to reproduce or/and compare various approaches due to the often-limited datasets comprising medical images. Since there is no open access dataset for the Gallbladder (GB) organ, we introduce, in this study, a large dataset that includes 10,692 GB Ultrasound Images (UI) acquired at high resolution from 1,782 individuals. These UI include many disease types related to the GB, and they are organized around nine important anatomical landmarks. The data in this collection can be used to train machine learning (ML) and deep learning (DL) models for computer-aided detection of GB diseases. It can also help academics conduct comparative studies and test out novel techniques for analyzing UI to explore the medical domain of GB diseases. The objective is then to help move medical imaging forward so that patients get better treatment.

Contrast-enhanced guided endoscopic ultrasound procedures

Contrast-enhanced endoscopic ultrasound (CH-EUS) can overcome the limitations of endoscopic ultrasound-guided acquisition by identifying microvessels inside inhomogeneous tumours and improving the characterization of these tumours. Despite the initial enthusiasm that oriented needle sampling under CH-EUS guidance could provide better diagnostic yield in pancreatic solid lesions, further studies did not confirm the supplementary values in cases of tissue acquisition guided by CH-EUS. This review details the knowledge based on the available data on contrast-guided procedures. The indications for CH-EUS tissue acquisition include isoechoic EUS lesions with poor visible delineation where CH-EUS can differentiate the lesion vascularisation from the surrounding parenchyma and also the mural nodules within biliopancreatic cystic lesions, which occur in select cases. Additionally, the roles of CH-EUS-guided therapy in patients whose pancreatic fluid collections or bile ducts that have an echogenic content have indications for drainage, and patients who have nonvisualized vessels that need to be highlighted via Doppler EUS are presented. Another indication is represented if there is a need for an immediate assessment of the post-radiofrequency ablation of pancreatic neuroendocrine tumours, in which case CH-EUS can be used to reveal the incomplete tumour destruction.

A Case of Asymptomatic Perforated Gangrenous Cholecystitis in a Diabetic Patient: A Critical Condition

Gangrenous cholecystitis (GC) is a severe form of acute cholecystitis (AC) with ischemia and necrosis of the gallbladder (GB) wall. Patients with GC are sicker than the usual AC patients, and their surgical treatment is more complex and linked with a higher risk of morbidity and mortality. Typically, the first imaging modality used to assess patients with clinically suspected AC is ultrasound. However, if the ultrasound results were inconclusive, a CT scan might help evaluate these individuals. Our study presents a 62-year-old male who presented with mild right upper quadrant discomfort. However, an abdominal computed tomography CT scan showed a pericholecystic fluid collection with a sign of GB perforation that was managed with subtotal cholecystectomy. Five days after the operation, the patient was discharged to home in excellent condition.

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.

Asymptomatic Gangrenous Acute Cholecystitis: A Life-Threatening Condition

Gangrenous gallbladder (GGB) is a life-threatening complication of acute cholecystitis, which happens due to gallbladder (GB) wall ischemia and necrosis. Delaying the diagnosis of GGB is life-threatening and may happen in asymptomatic patients. We present a case of an elderly male patient with a history of gastric carcinoid tumor, with partial gastric resection, who presented with generalized weakness and jaundice. His total bilirubin was elevated and an ultrasonography and computed tomography (CT) scan of the abdomen showed evidence of acute cholecystitis. An endoscopic retrograde cholangiopancreatography (ERCP) the day after admission showed no evidence of choledocholithiasis or cholangitis. It was during laparoscopic cholecystectomy three days later that the diagnosis of GGB was made as the GB was found to be necrotic with extensive adhesions. The patient also required intravenous antibiotics prior to discharge. This case illustrates risk factors for the development of gangrenous cholecystitis, physical findings in asymptomatic patients, and the importance of early diagnosis in order to reduce morbidity in this patient population.

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.

Distinguishing Between Gangrenous Cholecystitis and Ascending Cholangitis: A Case Study

Gangrenous cholecystitis is a potentially fatal complication of acute cholecystitis that presents with right upper quadrant pain and sepsis. Due to the overlap in clinical features with ascending cholangitis, gangrenous cholecystitis can be easily misdiagnosed, resulting in treatment delay. While the gold standard of diagnosis of gangrenous cholecystitis is direct visualization during surgery and tissue sampling to pathology, some imaging features can guide the diagnosis to appropriate early surgical treatment of gangrenous cholecystitis.

A 78-year-old female presented to the emergency department with right upper quadrant pain, sepsis, and altered mental status. Imaging findings on ultrasound and CT were suggestive of gangrenous cholecystitis. However, clinically the patient presented with ascending cholangitis symptoms. Instead of an emergent cholecystectomy, percutaneous cholecystostomy (PTC) was performed. After the PTC, the patient worsened clinically and despite surgical intervention, the patient expired due to septic shock and multiple organ failure.

Prediction of extensive necrotic change in acute gangrenous cholecystitis

PURPOSE

Gangrenous cholecystitis (GC) is a severe type of acute cholecystitis that implies higher mortality and morbidity rates than uncomplicated cholecystitis. The characteristics of GC are various for each case. However, preoperative predictors of GC with extensive necrotic change have not been investigated well.

METHODS

A total of 239 patients who were pathologically diagnosed with GC underwent laparoscopic cholecystectomy at our hospital between January 2013 and December 2021. Of these, 135 patients were included in this study and were subdivided into the extensive necrosis group (patients with necrotic change extending to the neck of the gallbladder, n = 18) and the control group (patients with necrotic change limited to the fundus or body, not extending to the neck, n = 117) according to each operation video. Patient characteristics and perioperative factors predicting extensive necrotic change were investigated.

RESULTS

Pericholecystic fat stranding (83.3 vs. 53.8%, p = 0.018) and absence of wall enhancement on preoperative CT images (50.0 vs. 24.7%, p = 0.026) were significantly associated with extensive necrosis. Seven of 18 patients in the extensive necrosis group showed necrotic changes beyond the infundibulum. The absence of wall enhancement on preoperative CT images (71.4 vs. 28.8%, p = 0.018) was significantly associated with necrotic changes beyond the infundibulum.

CONCLUSIONS

Pericholecystic fat stranding and absence of wall enhancement on preoperative enhanced CT are predictors of extensive necrotic change in patients with GC. In addition, the absence of wall enhancement also predicts the presence of necrotic changes beyond the infundibulum.

Evaluation of early sonographic predictors of gangrenous cholecystitis: mucosal discontinuity and echogenic pericholecystic fat

PURPOSE

To identify early sonographic features of gangrenous cholecystitis.

MATERIALS AND METHODS

101 patients with acute cholecystitis and a pre-operative sonogram were retrospectively reviewed by three radiologists in this IRB-approved and HIPAA-compliant study. Imaging data were correlated with histologic findings and compared using the Fisher's exact test or Student t test with p < 0.05 to determine statistical significance.

RESULTS

Forty-eight patients had gangrenous cholecystitis and 53 had non-gangrenous acute cholecystitis. Patients with gangrenous cholecystitis tended to be older (67 ± 17 vs 48 ± 18 years; p = 0.0001), male (ratio of male:female 2:1 vs 0.6:1; p = 0.005), tachycardic (60% vs 28%; p = 0.001), and diabetic (25% vs 8%; p = 0.001). Median time between pre-operative sonogram and surgery was 1 day. On imaging, patients with gangrenous cholecystitis were more likely to have echogenic pericholecystic fat (p = 0.001), mucosal discontinuity (p = 0.010), and frank perforation (p = 0.004), while no statistically significant differences were seen in the presence of sloughed mucosa (p = 0.104), pericholecystic fluid (p = 0.523) or wall striations (p = 0.839). In patients with gangrenous cholecystitis and echogenic pericholecystic fat, a smaller subset had concurrent mucosal discontinuity (57%), and a smaller subset of those had concurrent frank perforation (58%). The positive likelihood ratios for gangrenous cholecystitis with echogenic fat and mucosal discontinuity were 4.6 (95% confidence interval 1.9-11.3) and 14.4 (2.0-106), respectively.

CONCLUSION

Echogenic pericholecystic fat and mucosal discontinuity are early sonographic findings that may help identify gangrenous cholecystitis prior to late findings of frank perforation.

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.

Acute cholecystitis in recent lung transplant patients: a single-institution series of 10 cases

OBJECTIVE

To evaluate the clinical and imaging findings of acute cholecystitis in recent lung transplant patients.

METHODS

We retrospectively reviewed all abdominal ultrasounds and computed tomography (CT) scans of patients who developed acute cholecystitis in the early postoperative period following lung transplantation from November 2014 to December 2020 in a tertiary care university hospital.

RESULTS

Ten patients (4.4%) were included in this series (6 male, mean age 62.9 years ± 2.1 [standard deviation]) of a total 227 lung transplant patients performed from November 2014 to December 2020 (172 unilateral and 55 bilateral). Nine (90%) patients received a double-lung transplant and seven (70%) required extracorporeal circulation during surgery. Acute cholecystitis occurred during the initial admission for lung transplantation (average of 33 ± 25.9 days post-transplantation). Six patients (60%) died during admission with an average of 24.3 ± 21.8 days after cholecystectomy. The most frequent imaging findings were gallbladder wall discontinuity or decreased gallbladder mural enhancement (100%, 10 patients) and gallbladder distension (90%, 9 patients). All acute cholecystitis were found to be ischemic / gangrenous at surgery and/or pathology, 40% (4 patients) were hemorrhagic and 30% (3 patients) were perforated, one of them with a cholecystoduodenal fistula. Fungal cholecystitis was demonstrated at histological exam in one patient.

CONCLUSION

Acute cholecystitis in the early postoperative period after lung transplantation is an important cause of morbidity and mortality. Ischemic or gangrenous cholecystitis prevails. The key imaging findings are parietal perfusion defects and gallbladder distension, which can easily go unnoticed if not specifically looked for.

Gangrenous cholecystitis: Analysis of imaging findings in histopathologically confirmed cases

Purpose:

To study the imaging findings in gangrenous acute cholecystitis.

Materials and Methods:

Retrospective analysis of imaging findings in 31 histopathologically confirmed cases of gangrenous cholecystitis was done. The following imaging findings were analyzed: wall thickness, gallbladder distension, intraluminal membranes, mural striation, edema, wall enhancement, gallstones, gas, pericholecystic fluid, stranding, hemorrhage, hyperaemia in adjacent liver, mucosal/wall irregularity, complications.

Statistical Analysis:

Appropriate statistical tests were used using SPSS.22.0 software. The two proportions were compared using Chi-square or Fisher exact test and two means were compared using student t test.

Results:

Mean gallbladder wall thickening was 6 ± 1.93 mm. Gallstones, mural edema, mural striation, pericholecystic fluid, intraluminal membranes, gas were seen in 30, 27, 18, 20, 14 and 3 cases respectively. The mean short-axis distension of gallbladder lumen was 4.24 ± 0.91 cm. Gallbladder wall enhancement was studied in only 10 cases. Complete absence of enhancement was seen in 1, focal decreased enhancement in 8 cases. Mucosal/wall irregularity was seen in 28 cases. 74.2% cases had ≥4 cm gallbladder distension. Intraluminal membranes were present in 14 cases with mean short-axis distension of 4.6 cm and absent in 17 (P = 0.041), in 11 cases with mural striation (P = 0.036). Mean wall thickening was 6.69mm in patients with intraluminal membranes and 5.46 mm with absence of membranes (P = .078).

Conclusion:

Presence of more than one of these findings - gallbladder distension (short axis diameter of ≥4 cm), intraluminal membranes, mural striation, absent or decreased enhancement of gallbladder wall suggest high probability of gangrenous change in acute cholecystitis.

Occult Perforated Gangrenous Gallbladder Found on Magnetic Resonance Cholangiopancreatography

Acute gangrenous cholecystitis is a life-threatening disease that is most often diagnosed intraoperatively and can be missed on mildly symptomatic patients without the proper imaging modality. We present a case of a 69-year-old male with a history of hypertension, hyperlipidemia, and type 2 diabetes, and a recent right pontine infarct that arrived with 3 out of 10 right-sided abdominal pain. His liver ultrasound and computed tomography (CT) with contrast demonstrated acute cholecystitis. He was initially worked up conservatively and was scheduled for an elective cholecystectomy per surgery recommendation. However erring on the side of caution, the medical team had ordered a magnetic resonance cholangiopancreatography (MRCP), which demonstrated perforated gangrenous cholecystitis. Of note, the imaging modalities were ordered within a 24-hour window. The patient's antibiotics were promptly broadened, and he was emergently sent to the operating room. Moving forward, we will identify atypical clinical presentations of gangrenous cholecystitis and consider ordering an MRCP when clinical suspicion remains high and initial imaging is inconclusive. Perforated gangrenous cholecystitis is a severe disease and can cause rapid demise if not identified and treated early.

Complications of cholecystitis: a comprehensive contemporary imaging review

Acute cholecystitis is a common cause of right upper quadrant pain in patients presenting to the emergency department. Ultrasound, computed tomography, HIDA scans, and magnetic resonance imaging are increasingly utilized to evaluate suspected cases. The prognosis of acute cholecystitis is usually excellent with timely diagnosis and management. However, complications associated with cholecystitis pose a considerable challenge to the clinician and radiologist. Complications of acute cholecystitis may result from secondary bacterial infection or mural ischemia secondary to increased intramural pressure. The recognized subtypes of complicated cholecystitis are hemorrhagic, gangrenous, and emphysematous cholecystitis, as well as gallbladder perforation. Acute acalculous cholecystitis is a form of cholecystitis that occurs as a complication of severe illness in the absence of gallstones or without gallstone-related inflammation. Complicated cholecystitis may cause significant morbidity and mortality, and early diagnosis and recognition play a pivotal role in the management and early surgical planning. As appropriate utilization of imaging resources plays an essential role in diagnosis and management, the emergency radiologist should be aware of the spectrum of complications related to cholecystitis and the characteristic imaging features. This article aims to offer a comprehensive contemporary review of clinical and cross-sectional imaging findings of complications associated with cholecystitis. In conclusion, cross-sectional imaging is pivotal in identifying the complications related to cholecystitis. Preoperative detection of this complicated cholecystitis can help the care providers and operating surgeon to be prepared for a potentially more complicated procedure and course of recovery.

Complicated Acute Cholecystitis: The Role of C-Reactive Protein and Neutrophil-Lymphocyte Ratio as Predictive Markers of Severity

Objectives The clinical diagnosis of complicated acute cholecystitis (CAC) remains difficult with several pathological or ultrasonography criteria used to differentiate it from uncomplicated acute cholecystitis (UAC). This study aims to evaluate the use of combined inflammatory markers C-reactive protein (CRP) and neutrophil-to-lymphocyte ratio (NLR) as surrogate markers to differentiate between UAC and CAC. Methods We identified 600 consecutive patients admitted with biliary symptoms during an acute surgical take from our electronic prospectively maintained database over a period of 55 months. Only patients undergoing emergency cholecystectomy performed during the index admission were included. The primary outcome was the finding of CAC versus UAC. Results A total of 176 patients underwent emergency laparoscopic cholecystectomy (ELC) during the index admission, including 118 (67%) females with a median age of 51 years (range: 21-97 years). The proportion of UAC (130 [74%]) and CAC (46 [26%]) was determined along with demographic data. Multivariate regression analysis showed that patient's age (OR=1.047; p=0.003), higher CRP (OR=1.005; p=0.012) and NLR (OR=1.094; p=0.047) were significant independent factors associated with severity of cholecystitis. Receiver operating characteristic (ROC) analysis for CRP showed an AUC (area under the curve) of 0.773 (95% CI: 0.698- 0.849). Using a cut-off value of 55 mg/L for CRP, the sensitivity of CAC was 73.9% and specificity was 73.1% in predicting CAC. The median post-operative length of stay was four days. The conversion rate from laparoscopic cholecystectomy to open surgery was 2% (4/176), and 5% (9/176) patients suffered post-operative complications with no mortality at 30 days. Conclusion CRP, NLR and age were independent factors associated with the severity of acute cholecystitis. NLR and CRP can be used as surrogate markers to predict patients at risk of CAC during emergency admission, which can inform future guidelines. Moreover, ELC for CAC can be safely performed under the supervision of dedicated upper GI surgeons.

Preoperative Magnetic Resonance Cholangiopancreatography for Detecting Difficult Laparoscopic Cholecystectomy in Acute Cholecystitis

Previous studies have shown that signal intensity variations in the gallbladder wall on magnetic resonance imaging (MRI) are associated with necrosis and fibrosis in the gallbladder of acute cholecystitis (AC). However, the association between MRI findings and operative outcomes remains unclear. We retrospectively identified 321 patients who underwent preoperative magnetic resonance cholangiopancreatography (MRCP) and early laparoscopic cholecystectomy (LC) for AC. Based on the gallbladder wall signal intensity on MRI, these patients were divided into high signal intensity (HSI), intermediate signal intensity (ISI), and low signal intensity (LSI) groups. Comparisons of bailout procedure rates (open conversion and laparoscopic subtotal cholecystectomy) and operating times were performed. The recorded bailout procedure rates were 6.8% (7/103 cases), 26.7% (31/116 cases), and 40.2% (41/102 cases), and the median operating times were 95, 110, and 138 minutes in the HSI, ISI, and LSI groups, respectively (both p < 0.001). During the multivariate analysis, the LSI of the gallbladder wall was an independent predictor of both the bailout procedure (odds ratio [OR] 5.30; 95% CI 2.11–13.30; p < 0.001) and prolonged surgery (≥144 min) (OR 6.10, 95% CI 2.74–13.60, p < 0.001). Preoperative MRCP/MRI assessment could be a novel method for predicting surgical difficulty during LC for AC.

Diagnostic significance of the CT rim sign in cases of gangrenous cholecystitis

PURPOSE

To evaluate the association between the CT rim sign and gangrenous cholecystitis (GC) and increased surgical difficulty.

METHOD

Patients who had a contrast enhanced CT of the abdomen and pelvis, followed by non-elective cholecystectomy were analyzed. The scans were reviewed for the CT rim sign by radiologists blinded to the pathologic and clinical outcomes. Demographic and clinical characteristics were compared between patients with and without GC using t-tests or Wilcoxon ranked sum test for continuous variables, and Fishers' exact test for categorical variables, when appropriate. A logistic regression model was fitted with multiple risk factors. Odds ratios as well as 95% confidence intervals were then calculated for the risk factors. A secondary analysis predicting increased surgical difficulty, defined as an operative time of greater than 2 h or increased conversion rate to open surgery, was also examined.

RESULTS

A total of 100 patients were included; 20 of which had GC. On imaging, patients with GC were more likely to have a CT rim sign (65% vs 32.5%, OR = 3.80, 95% CI: 1.24-12.7, p = 0.011). The presence of the CT rim sign did not reach a statistically significant association with an operative time >2 h or conversion to open case (56.52% vs 33.77%, OR = 2.55, p = 0.056).

CONCLUSION

The CT rim sign can be utilized to raise the possibility of GC, however the presence of the CT rim sign does not demonstrate an association with increased surgical difficulty.

Can inflammatory biomarkers help in the diagnosis and prognosis of gangrenous acute cholecystitis? A prospective study

The diagnosis of gangrenous acute cholecystitis represents a diagnostic challenge for the physician and is rarely identified preoperatively. We report a longitudinal prospective study in 180 patients who underwent cholecystectomy for acute cholecystitis. A ROC curve was obtained to determine the preoperative cut-off for various biomarkers (neutrophil to lymphocyte ratio [NLR], C-reactive protein [CRP], platelet to lymphocyte ratio [PLR], lactate and procalcitonin) and their association with both preoperative and postoperative findings. The area under the curve (AUC) for NLR, CRP, PLR, lactate and procalcitonin was 0.75, 0.8, 0.65 and 0.6, respectively. NLR > 5 and CRP > 100 are still independent factors for gangrene (adjusted odds ratio [OR], 2 and 2.1, respectively).

Emphysematous Cholecystitis and Necrotizing Pancreatitis: Unusual Combination of Critical Pathology in a Healthy Young Patient

Emphysematous cholecystitis (EC) is a rare form of severe cholecystitis, more common among old, frail males, with comorbidities like diabetes mellitus and peripheral vascular disease. The coexistence of emphysematous cholecystitis with necrotizing pancreatitis is extremely uncommon and in the literature, though it has been reported, no case was of a young patient like the one we are describing. He was treated with laparoscopic cholecystectomy, and his pancreatitis managed conservatively.

Cholecystectomy for Complicated Gallbladder and Common Biliary Duct Stones: Current Surgical Management

Gallstone disease accounts for the vast majority of acute surgical admissions in the UK, with a major treatment being cholecystectomy. Practice varies significantly as to whether surgery is performed during the acute symptomatic phase, or after a period of recovery. Differences in practice relate to operative factors, patient factors, surgeon factors and hospital and trust wide policies. In this review we summarize recent evidence on management of gallstone disease, particularly with respect to whether cholecystectomy should occur during index presentation or following recovery. We highlight morbidity and mortality studies, cost, and patient reported outcomes. We speculate on barriers to change in service delivery. Finally, we propose potential solutions to optimize care.

Accuracy of pre-operative parameters in predicting severe cholecystitis-A systematic review

INTRODUCTION

Severity of cholecystitis can be defined by the presence of histopathological changes such as gangrene, perforation, and empyema. Severe cholecystitis correlates with higher morbidity and longer hospital stay. The present review aimed to identify the predictors of severe cholecystitis.

METHODS

Electronic databases including PubMed, Scopus, and Cochrane library were searched in the period of January 1980 to March 2019. The main outcome of this review was to assess the predictability of pre-operative parameters such as Leukocytosis, fever, tachycardia, gallbladder wall edema, gallbladder distension, serum platelet count, and gallbladder mural striation. The role of patients' characteristics including age, gender, and diabetes mellitus in predicting severe cholecystitis was also assessed.

RESULTS

A total of 8823 patients were analysed. The mean age of patients was 67.14 ± 4.17. The parameters that had the highest Odds ratio in predicting severe cholecystitis were all findings on CT scanning and included attenuation of arterial phase, mural striation of the gallbladder, and decreased gallbladder wall enhancement.

CONCLUSION

We conclude that CT findings were the most significant predictors of severe cholecystitis. Patients with clinical and laboratory predictors of severe cholecystitis should be urgently evaluated with contrast CT scan to rule out any severe complications.

Benign gallbladder diseases: Imaging techniques and tips for differentiating with malignant gallbladder diseases

Benign gallbladder diseases usually present with intraluminal lesions and localized or diffuse wall thickening. Intraluminal lesions of the gallbladder include gallstones, cholesterol polyps, adenomas, or sludge and polypoid type of gallbladder cancer must subsequently be excluded. Polyp size, stalk width, and enhancement intensity on contrast-enhanced ultrasound and degree of diffusion restriction may help differentiate cholesterol polyps and adenomas from gallbladder cancer. Localized gallbladder wall thickening is largely due to segmental or focal gallbladder adenomyomatosis, although infiltrative cancer may present similarly. Identification of Rokitansky-Aschoff sinuses is pivotal in diagnosing adenomyomatosis. The layered pattern, degree of enhancement, and integrity of the wall are imaging clues that help discriminate innocuous thickening from gallbladder cancer. High-resolution ultrasound is especially useful for analyzing the layering of gallbladder wall. A diffusely thickened wall is frequently seen in inflammatory processes of the gallbladder. Nevertheless, it is important to check for coexistent cancer in instances of acute cholecystitis. Ultrasound used alone is limited in evaluating complicated cholecystitis and often requires complementary computed tomography. In chronic cholecystitis, preservation of a two-layered wall and weak wall enhancement are diagnostic clues for excluding malignancy. Magnetic resonance imaging in conjunction with diffusion-weighted imaging helps to differentiate xathogranulomatous cholecystitis from gallbladder cancer by identifying the presence of fat and degree of diffusion restriction. Such distinctions require a familiarity with typical imaging features of various gallbladder diseases and an understanding of the roles that assorted imaging modalities play in gallbladder evaluations.

Combined hyperdense gallbladder wall-lumen sign: new computed tomography sign in acute gangrenous cholecystitis

Purpose

The objective of our study was to evaluate the combined hyperdense gallbladder wall-lumen sign on computed tomography (CT) in diagnosing gangrenous cholecystitis.

Material and methods

We retrospectively reviewed the unenhanced CT scans of surgically proven cases of acute gangrenous (GCh) and non-gangrenous cholecystitis (nonGCh). Eleven cases of pathologically proven acute gangrenous cholecystitis and 12 consecutive cases of surgically proven acute non-gangrenous cholecystitis that underwent CT at our institute were included in the study so as to have 1 : 1 control. The Hounsfield unit (HU) value of the gallbladder wall and intraluminal bile was measured. Interobserver variability for individual CT findings was also assessed.

Results

The gangrenous cholecystitis group had significantly higher HU values of wall and bile (median value of 33 HU vs. 21 HU and median value of 21 HU vs. 8.5 HU, respectively, p < 0.05). The area under the receiver operator characteristic curve for HU lumen was 0.80 (95% CI: 0.62-0.98, p = 0.014) with an ideal cut-off at 31.5 HU, where the sensitivity was 54.5% and specificity was 91.7%. HU lumen has an even better assessment for gangrenous cholecystitis with AUC of its ROC as 0.92 (95% CI: 0.80-1.00, p = 0.001) with an ideal cut-off at 12.5 HU, where the sensitivity was 81.8% and specificity was 91.7%. The combined wall-lumen cut-off is 35 HU with sensitivity of 100% and specificity of 75%.

Conclusion

A cut-off CT density value of the gallbladder wall of more than 31.5 HU, intraluminal bile more than 12.5 HU, and combined wall-lumen HU of more than 35 can predict GCh.

Risk Factors of Gangrenous Cholecystitis in General Surgery Patient Admitted for Cholecystectomy in King Abdul-Aziz University Hospital (KAUH), Saudi Arabia

Introduction

Gangrenous cholecystitis (GC) is known as perforation and necrosis of the gallbladder wall caused by ischemia ensuing to vascular insufficiency. Gangrenous cholecystitis is associated with a high risk of morbidity.

Aim

With a percentage of patients needing emergent help, our objective is to determine the risk factor of GC in KAUH.

Methods

Retrospective review of 334 patients who underwent cholecystectomy during 2016 to 2018 In king Abdul-Aziz University Hospital (KAUH). The data was gained from the medical record of KAUH. The variables are defined as follows: age, gender, AST, ALT, WBC, DM, bilirubin and stone. In order to determine the risk factors that influence (GC). the data entry done by using Google forms while the analysis was done by using SPSS version 21.

Results

Of 334 patients who underwent cholecystectomy, 57 patient (17.1%) had histologically confirmed gangrenous cholecystitis. Most of them female, 13 variables were identified that were associated with GC by univariate analysis: age 46.8 years, stone (82.5%), bilirubin is normal 9.9, mean white blood cell count 7.8, diabetes, fever, nausea, vomiting, CT finding, asparate aminotransferase, alanine aminotransferase and alkaline phosphatase.

Conclusion

Patient age was a clear factor for developing GC, male gender was a factor but no correlation was found, normal range of WBC, total bilirubin was in a normal level, vomiting and fever and nausea was less compared to other researchers, at last computed Tomography was not supportive and do not give any importance in detecting GC.

The delta neutrophil index is an early predictive marker of severe acute cholecystitis

BACKGROUND

Predicting severe acute cholecystitis (SAC) is important because the mortality rate is higher for patients with SAC than for non-SAC (NSAC) patients. We evaluated the predictive value of the delta neutrophil index (DNI), which is greater in patients with infectious and inflammatory conditions, for SAC among patients in the emergency department (ED).

METHODS

This retrospective observational study included 379 consecutive adult patients with AC admitted to the ED from January 2015 to December 2016. The included patients were classified into 2 groups (NSAC and SAC) according to the Tokyo Guidelines 2018. White blood cell (WBC) count, C-reactive protein (CRP) levels, and DNI values were assessed at ED admission.

RESULTS

The SAC group contained 28 patients (7.4%). DNI was among the early predictors of SAC and was an inflammatory marker with a significantly higher predictive value than WBC count or CRP level for detecting SAC. The predictive power of DNI was significantly higher than that of CRP when used in conjunction with WBC count, abdominal computed tomography, and clinical variables.

CONCLUSIONS

DNI measured at ED admission may serve as an early predictor of SAC.

A deceptive case of emphysematous cholecystitis complicated with retroperitoneal gangrene and emphysematous pancreatitis: clinical and computed tomography features

Purpose

Emphysematous cholecystitis (EC) is an uncommon, severe variant of acute cholecystitis caused by gas- forming bacteria – most often Clostridium perfringens and Escherichia coli. We present a deceptive case of EC associated with retroperitoneal gas gangrene and emphysematous pancreatitis.

Case report

An 86-year-old, overweight woman was admitted to the emergency department with non-specific abdominal symptoms. Admission laboratory tests showed elevated diastase levels indicating acute pancreatitis. Computed tomography (CT) demonstrated a substantial amount of gas in the retroperitoneum and peritoneal cavity, which raised a suspicion of duodenal perforation. Primary diagnosis was not confirmed during emergency laparotomy, which revealed a gangrenous gallbladder adjacent to the duodenum and surrounded by purulent fluid. The final diagnosis established after laparotomy and rereading of CT scans was that of emphysematous cholecystitis associated with gangrenous pancreatitis and retroperitoneal gangrene. After surgery, the patient was transferred to the intensive care unit in septic shock. Shortly after, the second laparotomy was undertaken on suspicion of internal bleeding. During surgery, the patient experienced cardiac arrest and died despite immediate resuscitation.

Conclusions

Emphysematous cholecystitis may be associated with a spread of infection both to the peritoneal cavity and retroperitoneum and result in a substantial amount of gas in those anatomic compartments. The knowledge of this rare complication may be helpful in establishing a correct diagnosis.

Gangrenous cholecystitis: A silent but potential fatal disease in patients with diabetic neuropathy. A case report

Gangrenous cholecystitis (GC) is a severe and potentially deadly complication of acute cholecystitis. We present a 83-year-old gentleman with a past medical history of type 2 diabetes mellitus with significant associated neuropathy, presenting to a community hospital in a major metropolitan area with 10 days nausea and vomiting and a benign abdominal exam. While the patient was admitted for hyperglycemia, he was subsequently found to have severe GC requiring urgent surgical intervention.

The impact of a rapid imaging protocol in acute cholecystitis-prospective cohort study

•

A rapid imaging protocol with defined clinical criteria for acute cholecystitis (AC) resulted in significant improvements in perioperative and quality measures.

•

Acute on chronic cholecystitis (ACC) may present with typical and/or atypical clinical features of AC, and was the most common pathology found in our specimens for the RIP.

•

HIDA and CT scan had similar performance for de novo AC. However, diagnostic performance for both studies was reduced in the setting of ACC.

•

Delayed filling of the gallbladder on HIDA in a patient with high risk features is ACC until proven otherwise, and urgent cholecystectomy should be considered.

Introduction

In this study we assess the impact of a “rapid imaging protocol” (RIP) on outcomes in patients with suspected acute cholecystitis (AC).

Methods

From January 2017 to January 2018, a prospective cohort study was implemented using a RIP with hepatoscintigraphy (HIDA) or CT scan (first available, goal within 4 h) in patients (n = 52) presenting with highly suspected AC and a clinical feature score of ≥1. For the latter, the following presenting features were scored as follows: 1 point for WBC count ≥10,000 (10⁹/L), 1.5 points for glucose ≥140 (mg/dl), and/or 1 point for age ≥50 yrs. The historical control was all patients admitted with suspected AC in a 1.5-year period (n = 117) under our previous “delayed imaging protocol” (DIP), which used US ± HIDA (post-admission) in select patients. Primary end points included: compare outcome and quality measures between the groups, evaluate diagnostic imaging performance for AC, and evaluate our proposed clinical feature score in the setting of AC.

Results

Histopathologic features consistent with AC was more frequent in patients in the RIP (64% vs 39%, p = 0.008). The pooled positive predictive value of HIDA and CT scan for AC were 85% vs 94%, respectively. The RIP was associated with a significant reduction in time to surgery, length of stay, and conversions to open (p < 0.001, respectively). A clinical feature score of 3.5 predicted the likelihood of AC in 95% of the cases (x² for linear trend = 42, p < 0.001).

Conclusion

A protocol centered around rapid identification, defined clinical criteria (i.e. clinical feature score), and confirmation with non-user dependent imaging modalities has resulted in favorable outcomes. CT may be the study of choice when the likelihood of AC is high because it is superior at identifying severity.

Atypical presentation of gangrenous cholecystitis: A case series

Gangrenous cholecystitis (GC) is a serious complication of acute cholecystitis that has been associated with increased morbidity. Patient with GC can present with a wide variety of non-specific clinical, laboratory, and imaging characteristics, making the diagnosis challenging. This disease requires emergent treatment, which is why a quick and reliable diagnosis is essential for the wellbeing of the patient. The authors herein present a case of GC in a patient whose initial complaint was intractable hiccups, and provide a thorough review of the literature of cases of GC with atypical presentations.

Frequency-selective non-linear blending for the computed tomography diagnosis of acute gangrenous cholecystitis: Pilot retrospective evaluation

Purpose

To compare the diagnostic performance of frequency-selective non-linear blending and conventional linear blending contrast-enhanced CT for the diagnosis of acute (AC) and gangrenous (GC) cholecystitis.

Materials and methods

Following local ethics committee approval for retrospective data analysis, a database search derived 39 patients (26 men, mean age 67.8 ± 14.6 years) with clinical signs of acute cholecystitis, contrast enhanced CT (CECT) evaluation, cholecystectomy, and pathological examination of the resected specimen. The interval between CECT and surgery was 4.7 ± 4.1 days. Pathological gross examination was used to categorize the cases into AC and GC. Subsequently, two radiologists categorized the CECT studies in a blinded and independent fashion into AC and GC, during two different reading sessions using linear blending and frequency-selective non-linear blending CECT.

Results

Histologic analysis diagnosed 31/39 (79.4%) cases of GC and 8/39 (20.6%) cases of AC. Image interpretation of linear blending CECT resulted in classification of 7/39 (17.9%) patients as GC and 32/39 (82.1%) as AC, whereas image interpretation of frequency-selective non-linear blending CECT resulted in classification of 29/39 (74.3%) patients as GC and 10/39 (25.7%) as AC. Sensitivity/specificity/PPV/NPV for detection of GC were 22.6%/100%/100%/25% with linear blending CECT and 80.6%/50%/86.2%/40% with frequency-selective non-linear blending CECT, respectively. Based on the histopathologic diagnosis frequency-selective non-linear blending had a significant improvement (p > 0.0001) in the diagnostic accuracy of gangrenous cholecystitis compared with linear blending.

Conclusion

Frequency-selective non-linear blending post-processing increases the diagnostic accuracy of gangrenous cholecystitis owing to improved visualization of absence of focal enhancement and mural ulcerations.

Differentiation of acute cholecystitis from chronic cholecystitis: Determination of useful multidetector computed tomography findings

The purpose of this study was to determine the diagnostic value of multidetector computed tomography (MDCT) imaging findings, to identify the most predictive findings, and to assess diagnostic performance in the diagnosis and differentiation of acute cholecystitis from chronic cholecystitis.In this retrospective study, we enrolled 382 consecutive patients with pathologically proven acute or chronic cholecystitis who underwent computed tomography (CT) within 1 month before surgery. The CT findings were compared and logistic regression analysis was used to identify significant CT findings in predicting acute cholecystitis. Diagnostic performance of each CT finding and of combined findings was also assessed.Statistically significant CT findings distinguishing acute cholecystitis from chronic cholecystitis were increased gallbladder dimension (85.5% vs 50.6%, P < .001), increased wall enhancement (61.8% vs 78.9%, P = .001), increased wall thickness (67.9% vs 31.1%, P < .001), mural striation (64.9% vs 28.3%, P < .001), pericholecystic haziness or fluid (66.4% vs 21.2%, P < .001), increased adjacent hepatic enhancement (80.0% vs 32.4%, P < .001), focal wall defect (9.2% vs 0, P < .001), and pericholecystic abscess (10.7% vs 0, P < .001). Subsequent multivariate logistic regression analysis revealed that increased adjacent hepatic enhancement [P = .006, odds ratio (OR) = 3.82], increased gallbladder dimension (P = .027, OR = 3.12), increased wall thickening or mural striation (P = .019, OR = 2.89), and pericholecystic haziness or fluid (P = .032, OR = 2.61) were significant predictors of acute cholecystitis. When 2 of these 4 CT findings were observed together, the sensitivity, specificity, and accuracy for the detection of acute cholecystitis were 83.2%, 65.7%, and 71.7%, respectively. When 3 of these 4 CT findings were observed together, the sensitivity, specificity, and accuracy were 56.5%, 84.5%, and 74.9%, respectively. When none of these 4 CT findings were observed, the negative predictive value was 96.4%.Increased adjacent hepatic enhancement, increased gallbladder dimension, increased wall thickening or mural striation, and pericholecystic fat haziness or fluid were the most discriminative MDCT findings for the diagnosis and differentiation of acute cholecystitis from chronic cholecystitis.

[Acute acalculous gangrenous cholecystitis in postoperative period after orthopedic surgery: about a case]

La cholécystite gangreneuse alithiasique postopératoire est une complication grave et sévère, surtout chez les malades hospitalisés en réanimation. Elle survient le plus souvent au décours d'une chirurgie vasculaire ou digestive majeure, d'un polytraumatisme, dans un contexte septique ou dans un contexte de choc. Nous rapportons l'observation d'un homme âgé de 74 ans opéré d'une fracture du col du fémur, au sixième jour postopératoire il a développé un tableau clinique d'une cholécystite aigue dont les explorations radiologiques ont confirmé son caractère alithiasique. Après une cholécystectomie en urgence, l'étude anatomopathologique a conclu à une cholécystite gangreneuse alithiasique.

Risk Factors for Difficult Laparoscopic Cholecystectomy in Acute Cholecystitis

Background and Objectives:

Factors that contribute to difficult laparoscopic cholecystectomy (LC) in acute cholecystitis (AC) that would affect the performance of early surgery remain unclear. The purpose of this study was to identify such risk factors.

Methods:

One hundred fifty-four patients who underwent LC for AC were retrospectively analyzed. The patients were categorized into early surgery and delayed surgery. Factors predicting difficult LC were analyzed for each group. The operation time, bleeding, and cases of difficult laparoscopic surgery (CDLS)/conversion rate were analyzed as an index of difficulty. Analyses of patients in the early group were especially focused on 3 consecutive histopathological phases: edematous cholecystitis (E), necrotizing cholecystitis (N), suppurative/subacute cholecystitis (S).

Results:

In the early group, the CDLS/conversion rate was highest in necrotizing cholecystitis. Its rate was significantly higher than that of the other 2 histopathological types (N 27.9% vs E and S 7.4%; P = .037). In the delayed-surgery group, a higher white blood cell (WBC) count and older age showed significant correlations with the CDLS/conversion rate (P = .034 and P = .004).

Conclusion:

In early surgery, histopathologic necrotizing cholecystitis is a risk factor for difficult LC in AC. A higher WBC count and older age are risk factors for delayed surgery.

Imaging of acute cholecystitis and cholecystitis-associated complications in the emergency setting

Acute cholecystitis is a common cause of right upper quadrant pain in patients presenting at the emergency department. Early diagnosis and recognition of associated complications, though challenging, are essential for timely management. Imaging studies, including ultrasonography, computed tomography and magnetic resonance imaging, are increasingly utilised for the evaluation of suspected cases of cholecystitis. These investigations help in diagnosis, identification of complications and surgical planning. Imaging features of acute cholecystitis have been described in the literature and are variable, depending on the stage of inflammation. This article discusses the spectrum of cholecystitis-associated complications and their imaging manifestations. We also suggest a checklist for the prompt and accurate identification of complications in acute cholecystitis.

Use of dynamic CT attenuation value for diagnosis of acute gangrenous cholecystitis

OBJECTIVE

To determine if the increase in transient focal enhancement of the liver adjacent to the gallbladder seen on dynamic computed tomography (CT) is greater in gangrenous cholecystitis than in nongangrenous cholecystitis by determining the CT attenuation value.

METHODS

We retrospectively reviewed the medical records of 57 patients who underwent emergency cholecystectomy for acute cholecystitis and preoperative dynamic CT scans between March 2011 and April 2016. Based on the pathology findings, patients were assigned to a gangrenous group or a nongangrenous group. The CT attenuation ratio (AR) was defined as the ratio of the maximum CT attenuation value in the region of interest in segment 5 (liver parenchyma adjacent to the gallbladder) and that in the control region of interest in segment 8. The patient characteristics and CT findings were compared between the groups. The appropriate AR of the arterial phase (ARAP) cutoff value for a diagnosis of gangrenous cholecystitis was determined using receiver operating characteristic curve analysis.

RESULTS

The ARAP was significantly higher in the gangrenous group than in the nongangrenous group (P < .001); the area under the receiver operating characteristic curve was 0.849. The ARAP cutoff value of 1.46 had a sensitivity and specificity of 84.6% and 83.9%, respectively (odds ratio, 21.17; 95% confidence interval, 4.90-118.91), and ARAP ≥1.46 was significantly correlated with a diagnosis of gangrenous cholecystitis (P < .001).

CONCLUSIONS

The increase in transient focal enhancement of the liver adjacent to the gallbladder during the arterial phase of dynamic CT was greater in gangrenous cholecystitis than in nongangrenous cholecystitis.

CT Findings for Detecting the Presence of Gangrenous Ischemia in Cholecystitis

OBJECTIVE

The objective of our study was to evaluate the diagnostic accuracy of CT in differentiating gangrenous cholecystitis from uncomplicated cholecystitis and healthy gallbladders.

MATERIALS AND METHODS

We performed a retrospective review of 308 patients with histologically proven gangrenous cholecystitis who underwent preoperative CT 1 month before gallbladder removal over a 4-year period. Two readers who were blinded to the histologic diagnosis independently recorded CT features of and overall likelihood of gangrenous cholecystitis on a 5-point scale (1, definitely absent; 5, definitely present). Ratings were dichotomized such that a diagnosis was considered present at a rating of 4 or 5 and considered absent at lower ratings. Interobserver variability for individual CT findings was also assessed.

RESULTS

Patients had gangrenous cholecystitis (n = 28), acute cholecystitis (n = 98), chronic cholecystitis (n = 118), or healthy gallbladders (n = 64). Multivariate analysis showed that CT findings of gallbladder distention greater than 4.0 cm (odds ratio [OR], 9.63; p < 0.01), mural striation (OR, 11.39; p < 0.01), and decreased mural enhancement (OR, 3.55; p < 0.05) independently predicted gangrenous cholecystitis. Using these CT features, the diagnosis of gangrenous cholecystitis was made with a specificity of 93.9% and 89.6% for readers 1 and 2, respectively, and accuracy of 90.9% and 87.0%, respectively. Good agreement was seen between the two readers with respect to gallbladder distention greater than 4.0 cm (κ = 0.77) and decreased mural enhancement (κ = 0.64).

CONCLUSION

A markedly distended gallbladder associated with decreased wall enhancement is highly specific for gangrenous cholecystitis.

Risk assessment scales and predictors for simple versus severe cholecystitis in performing laparoscopic cholecystectomy

BACKGROUND

Because acute cholecystitis has a different prognosis according to the degree of inflammation, early detection and prompt operation of severe cholecystitis are critical to the success of treatment. However, computed tomography (CT) has a low discriminative value for differentiating between simple and severe cholecystitis. Therefore, to enhance the diagnostic accuracy of CT scan, the imaging studies should be supplemented by preoperative clinical variables.

METHODS

Patients undergoing laparoscopic cholecystectomy for simple and severe cholecystitis between 2007 and 2014 were compared. Severe cholecystitis included hemorrhagic, gangrenous, emphysematous, xanthogranulomatous, and perforated cholecystitis. Prediction models for severe cholecystitis were developed based on multivariate analyses of preoperative clinical and radiologic variables.

RESULTS

Independent factors related with severe cholecystitis were age ≥65 years, male gender, body mass index (BMI) ≥25, serum leukocyte count ≥10,000/mm³, serum neutrophil fraction ≥80%, serum platelet count ≥20,000/mm³, serum alanine transaminase (ALT) level ≥40 IU/L, admission via the emergency department, and radiologic features of gallbladder wall thickening ≥4 mm, and presence of pericholecystic fluid collection (p < 0.05). A standard risk assessment scale (range: 0-77) for severe cholecystitis was developed based on the individual hazard rate of these variables. Patients scoring ≥28 on the risk assessment scale showed an 8.6 higher odds of severe cholecystitis than those scoring <28 (p < 0.01).

CONCLUSION

Standard and quick-and-easy predictive models for severe cholecystitis have been developed based on preoperative radiological and clinical variables, which is expected to help improve surgical outcome of patients with cholecystitis.

Hollow organ abdominal ischemia, part II: clinical features, etiology, imaging findings and management

Acute hollow organ ischemia commonly presents with acute pain prompting radiologic evaluation and almost always requires urgent treatment. Despite different risk factors and anatomic differences, ischemia is commonly due to low flow states but can also be due to arterial and venous occlusion. Radiologic diagnosis is critical as many present with nonspecific symptoms. Contrast-enhanced computed tomography (CT) is the modality of choice. Magnetic resonance imaging (MRI) is preferred in suspected appendicitis in pregnant patients and is superior in biliary necrosis. This article provides a pictorial review of the CT/MRI features of hollow abdominal organ ischemia while highlighting key clinical features, pathogenesis, and management.

Contrast-enhanced ultrasonography to diagnose complicated acute cholecystitis

Gangrenous cholecystitis and perforation are severe complications of acute cholecystitis, which have a challenging preoperative diagnosis. Early identification allows better surgical management. Contrast-enhanced computed tomography (ceCT) is the current diagnostic gold standard. Contrast-enhanced ultrasonography (CEUS) is a promising tool for the diagnosis of gallbladder perforation, but data from the literature concerning efficacy are sparse. The aim of the study was to evaluate CEUS findings in pathologically proven complicated cholecystitis (gangrenous, perforated gallbladder, pericholecystic abscess). A total of 8 patients submitted to preoperative CEUS, and with subsequent proven acute complicated cholecystitis at surgical inspection and pathological analysis, were retrospectively identified. The final diagnosis was gangrenous/phlegmonous cholecystitis (n. 2), phlegmonous/ulcerative changes plus pericholecystic abscess (n. 2), perforated plus pericholecystic abscess (n. 3), or perforated plus pericholecystic biliary collection (n. 1). Conventional US findings revealed irregularly thickened gallbladder walls in all 8 patients, with vaguely defined walls in 7 patients, four of whom also had striated wall thickening. CEUS revealed irregular enhancing gallbladder walls in all patients. A distinct wall defect was seen in six patients, confirmed as gangrenous/phlegmonous cholecystitis at pathology in all six, and in four as perforation at macroscopic surgical inspection. CEUS is a non-invasive easily repeatable technique that can be performed at the bedside, and is able to accurately diagnose complicated/perforated cholecystitis. Despite the limited sample size in the present case series, CEUS appears as a promising tool for the management of patients with the clinical possibility of having an acute complicated cholecystitis.

Utility of diffusion-weighted MRI for differentiating acute from chronic cholecystitis

PURPOSE

To assess the use of diffusion-weighted imaging (DWI) for differentiating acute from chronic cholecystitis, in comparison with conventional magnetic resonance imaging (MRI) features.

MATERIALS AND METHODS

Liver MRI including DWI (b-values 0/500/1000s/mm(2) ) was performed at 1.5T ≤30 days before cholecystectomy in 83 patients with abdominal pain. Two radiologists assessed cases for conventional (gallstones, wall thickening, pericholecystic fluid, pericholecystic fat changes, gallbladder distension, pericholecystic liver enhancement, mural T2 -hyperintensity, mural hyperenhancement, mural striations, abscess, intraluminal membranes, and mural defect) and DWI (increased mural signal on high b-value images, visually low apparent diffusion coefficient [ADC], and ADC values) features.

RESULTS

Acute cholecystitis was present in 43%; chronic cholecystitis was present in 57%. Nine of 12 conventional features were more frequent in acute cholecystitis for both readers (P ≤ 0.003). Increased mural signal on high b-value images was more frequent (P < 0.001) in acute than chronic cholecystitis for R1 (92% vs. 32%) and R2 (83% vs. 30%). Sensitivity and specificity of increased signal on high b-value images were: R1, 92%/68%; R2, 83%/70%. Visually low ADC was more frequent in acute cholecystitis for R2 (P < 0.001) but not R1 (P = 0.406); ADC values were not different between groups for either reader (P = 0.104-0.139). Among conventional and DWI features, only increased signal on high b-value DWI was independently associated with acute cholecystitis for both readers (P = 0.006-0.012).

CONCLUSION

Visually increased mural signal on high b-value DWI was highly sensitive and moderately specific for acute cholecystitis, being an independent predictor relative to conventional features for both readers. Although requiring larger studies, DWI (particularly the high b-value images) may have additive value relative to conventional MRI-suspected acute cholecystitis. J. Magn. Reson. Imaging 2016;44:89-97.