Acute cholecystitis: quantitative and qualitative evaluation with 64-section helical CT

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%.

Imaging of hepato-pancreato-biliary emergencies in patients with cancer

Hepato-pancreato-biliary (HPB) emergencies in patients with cancer encompass an extensive array of various conditions, including primary malignancies that require prompt treatment, associated severe complications, and life-threatening consequences arising from treatment. In patients with cancer, the liver can be affected by chemotherapy-induced hepatotoxicity, veno-occlusive disease, Budd-Chiari syndrome, liver hemorrhage, and other complications arising from cancer therapy with all these complications requiring timely diagnosis and prompt treament. Cholecystitis induced by systemic anticancer therapies can result in severe conquences if not promptly identified and treated. The application of immunotherapy in cancer therapy is associated with cholangitis. Hemobilia, often caused by medical interventions, may require arterial embolization in patients with severe bleeding and hemodynamic instability. Malignant biliary obstruction in patients with biliary cancers may necessitate palliative strategies such as biliary stenting. In pancreatic cancer, patients often miss surgical treatment due to advanced disease stages or distant metastases, leading to potential emergencies at different treatment phases. This comprehensive review underscores the complexities of diagnostic and treatment roles of medical imaging in managing HPB emergencies in patients with cancer. It illustrates the crucial role of imaging techniques, including magnetic resonance imaging, computed tomography and ultrasound, in diagnosing and managing these conditions for timely intervention. It provides essential insights into the critical nature of early diagnosis and intervention in cancer-related HPB emergencies, ultimately impacting patient outcomes and survival rates.

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.

A nomogram for clinical estimation of acute biliary pancreatitis risk among patients with symptomatic gallstones: A retrospective case-control study

Background/Purpose

Currently, there are no effective tools to accurately assess acute biliary pancreatitis (ABP) risk in patients with gallstones. This study aimed to develop an ABP risk nomogram in patients with symptomatic gallstones.

Methods

We conducted a retrospective nested case-control study and data on 816 conservatively treated patients with symptomatic gallstones admitted to The First Affiliated Hospital of Harbin Medical University between January 6, 2007 and January 22, 2016 were retrospectively collected. We conducted a propensity-score matched (PSM) analysis based on follow-up time in a ratio of 1:4 between ABP group (n=65) and non-ABP group (n=260). These matched patients were randomly divided into study cohort (n=229) and validation cohort (n=96) according to a ratio of 7:3. In the study cohort, independent risk factors for ABP occurrence identified using Cox regression were included in nomogram. Nomogram performance and discrimination were assessed using the concordance index (C-index), area under the curve (AUC), calibration curve, decision curve analysis (DCA) and clinical impact curve (CIC). The model was also validated in the validation cohort.

Results

Nomogram was based on 7 independent risk factors: age, diabetes history, gallbladder wall thickness, gallstone diameter, coexisting common bile duct (CBD) stones, direct bilirubin (DBIL), and white blood cell count (WBC). The C-index of nomogram was 0.888, and the 10-year AUCs of nomogram was 0.955. In the validation cohort, nomogram still had good discrimination (C-index, 0.857; 10-year AUC, 0.814). The calibration curve showed good homogeneity between the prediction by nomogram and the actual observation. DCA and CIC demonstrated that nomogram was clinically useful.

Conclusions

The ABP risk nomogram incorporating 7 features is useful to predict ABP risk in symptomatic gallstone patients.

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.

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.

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.

A scoring system based on computed tomography for the correct diagnosis of xanthogranulomatous cholecystitis

Background

Xanthogranulomatous cholecystitis (XGC) is an uncommon variant of chronic cholecystitis. The differential diagnoses of XGC include gallbladder cancer (GBC), adenomyomatosis, and actinomycosis of the gallbladder.

Purpose

To assess the usefulness of computed tomography (CT) findings in the diagnosis of XGC and differentiation from GBC.

Material and Methods

We retrospectively assessed the pathological and radiological records of 13 patients with pathologically proven XGC and 33 patients with GBC.

Results

Significant differences were observed for the following five CT findings: diffuse wall thickening (XGC = 85%, GBC = 15%, P < 0.01); absence of polypoid lesions (XGC = 100%, GBC = 48%, P < 0.01); intramural nodules or bands (XGC = 54%, GBC = 9%, P < 0.01); pericholecystic infiltration (XGC = 69%, GBC = 9%, P < 0.01); and pericholecystic abscess (XGC = 23%, GBC = 0%, P = 0.018). We defined the scoring system based on how many of the five CT findings were observed. Our scoring system, which included these findings, revealed that patients with three or more findings had sensitivity of 77% (95% confidence interval [CI] = 57–87) and specificity of 94% (95% CI = 86–98).

Conclusion

Our scoring system can assist in the differentiation of XGC from GBC.

The Treatment of Gallstone Disease

BACKGROUND

Gallstone disease affects up to 20% of the European population, and cholelithiasis is the most common reason for hospitalization in gastroenterology.

METHODS

This review is based on pertinent publications retrieved by a selective search of the literature, including the German clinical practice guidelines on the diagnosis and treatment of gallstones and corresponding guidelines from abroad.

RESULTS

Regular physical activity and an appropriate diet are the most important measures for the prevention of gallstone disease. Transcutaneous ultrasonography is the paramount method of diagnosing gallstones. Endoscopic retrograde cholangiography should only be carried out as part of a planned therapeutic intervention; endosonography beforehand lessens the number of endoscopic retrograde cholangiographies that need to be performed. Cholecystectomy is indicated for patients with symptomatic gallstones or sludge. This should be performed laparoscopically with a four-trocar technique, if possible. Routine perioperative antibiotic prophylaxis is not necessary. Cholecystectomy can be performed in any trimester of pregnancy, if urgently indicated. Acute cholecystitis is an indication for early laparoscopic cholecystectomy within 24 hours of admission to hospital. After successful endoscopic clearance of the biliary pathway, patients who also have cholelithiasis should undergo laparoscopic cholecystectomy within 72 hours.

CONCLUSION

The timing of treatment for gallstone disease is an essential determinant of therapeutic success.

Evaluation of the CT Scan as the First Examination for the Diagnosis and Therapeutic Strategy for Acute Cholecystitis

BACKGROUND

The CT scan has supplanted the abdominal ultrasound for emergency examinations. A comparison of CT scan and ultrasound performance for the diagnosis and management of acute cholecystitis in acute care was proposed. The hypothesis is that the CT scan may be sufficient for the diagnosis of acute cholecystitis, which would allow faster progress to surgery.

METHODS

The retrospective study of consecutive patients operated for acute cholecystitis or gallbladder distension with pre-operative imaging within 48 h in one centre.

RESULTS

Between 2015 and 2017, a total of 341 cholecystectomies were performed in our centre. The analysis involved 120 patients. Ultrasound had better sensitivity than the CT scan, respectively, 79.4% [70.5-86.6] and 52.3% [42.5-62.1], but less specificity, with 61.5% [31.6-86.1] and 92.3% [64.0-99.8], respectively. However, there was a significant difference in favour of the CT scan for the diagnosis of complicated cholecystitis (p 0.004). The positive likelihood ratio of complicated cholecystitis is better at CT scan (7.8) [2.7-23.1] than in ultrasound (1.0) [0.1-9.7]. CT scan and ultrasound are equivalent for the diagnosis of acute cholecystitis, but CT scan is more efficient for the diagnosis of complicated cases (Youden index J 0.3 vs 0.001).

CONCLUSION

It is possible to place the surgical indication of cholecystectomy on the only data of the CT scan. We propose a decision-making algorithm that uses the CT scan to make the diagnosis and decide on emergency treatment for complicated cases or that allows us to propose a delayed surgery for simple cholecystitis.

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.

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

OBJECTIVE

In 2013, a multidisciplinary group at our Veterans Administration hospital collaborated to improve the diagnosis and treatment of patients with acute cholecystitis (AC) at our facility. Our role in this project was to evaluate the diagnostic accuracies of ultrasound (US) and CT.

MATERIALS AND METHODS

AC was diagnosed in 60 patients (62 patient encounters) between July 1, 2013, and July 1, 2015. Of these patients, 56 underwent US, 48 underwent CT, and 42 underwent both. For the same time period, 60 patients without AC underwent US and 60 patients without AC underwent CT, and these imaging studies served as comparison studies. The groups were combined for a total of 182 unique patient encounters. A single radiologist reviewed the studies and tabulated the data.

RESULTS

The sensitivity of CT for detecting AC was significantly greater than that of US: 85% versus 68% (p = 0.043), respectively; however, the negative predictive values of CT and US did not differ significantly: 90% versus 77% (p = 0.24-0.26). Because there were no false-positives, the specificity and positive predictive values for both modalities were 100%. Among the 42 patients who underwent CT and US, both modalities were positive for AC in 25 patients, CT was positive and US was negative in 10 patients, and US was positive and CT was negative in two patients; in five patients, both US and CT were negative.

CONCLUSION

CT was significantly more sensitive for diagnosing AC than US. CT and US are complementary, and the other modality should be considered if there is high clinical suspicion for AC and the results of the first examination are negative.

Noninvasive Imaging of the Biliary System Relevant to Percutaneous Interventions

Clinical data such as history, physical examination, and laboratory tests are useful in identifying patients with biliary obstruction and biliary sources of infection. However, if intervention is planned, noninvasive imaging is needed to confirm the presence, location, and extent of the disease process. Currently, the most commonly available and used noninvasive modalities are ultrasound (US), computed tomography (CT), magnetic resonance (MR), and nuclear medicine hepatobiliary scintigraphy (HIDA). US is quick, portable, readily available, and is commonly the first imaging modality used when biliary pathology is suspected. It is excellent in the detection of cholelithiasis and acute cholecystitis but is limited in detecting choledocholithiasis. CT is excellent at detecting infected postoperative fluid collections, bilomas, biliary obstruction, and biliary infection but is limited in the detection of cholelithiasis. Therefore, US may be more useful than CT for the initial screening of acute biliary disease. MR has inherent advantages over CT, as it does not use ionizing radiation, can be done without intravenous contrast, and its detection of cholelithiasis is not affected by the internal composition of the stone. Magnetic resonance cholangiopancreatography can be used to determine the cause and location of biliary obstruction but is limited in the detection of small stones and the evaluation of the biliary tract near the ampulla. HIDA is used to evaluate for cholecystitis, biliary obstruction, and bile leaks. The main limitation is its lack of anatomical detail, and it is therefore frequently performed in conjunction with other described modalities.

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.

Cystic Duct Enhancement: A Useful CT Finding in the Diagnosis of Acute Cholecystitis Without Visible Impacted Gallstones

OBJECTIVE

The purpose of this study was to determine the incremental value of the presence of cystic duct enhancement for diagnosing acute cholecystitis without visible impacted gallstones.

MATERIALS AND METHODS

CT scans of 63 patients with acute cholecystitis and 63 control subjects were retrospectively and independently reviewed by two radiologists to determine the presence of cystic duct enhancement or impacted stones. Two additional radiologists were then asked to independently evaluate all CT images using a 5-point scoring system for diagnosing acute cholecystitis. They conducted the evaluations both before and after being informed that cystic duct enhancement could be substituted for a CT finding of impacted gallstones.

RESULTS

The prevalence of either cystic duct enhancement or stone impaction was observed to be significantly more common in the patient group (86-91%) than in the control group (6-14%) (p < 0.001) with good interobserver agreement (κ = 0.79). Diagnostic sensitivities increased significantly from 60.3% to 85.7% for reviewer 1 (p = 0.001) and from 71.4% to 87.3% for reviewer 2 (p = 0.028) after the reviewers were informed of the presence of cystic duct enhancement. Diagnostic accuracy increased significantly for the less experienced radiologist, from 75.4% to 87.3% (p = 0.015).

CONCLUSION

The accuracy and sensitivity of CT for the diagnosis of acute cholecystitis improved significantly when cystic duct enhancement was used as an alternative to impacted gallstones as a diagnostic criterion.

Computed Tomography Is More Sensitive than Ultrasound for the Diagnosis of Acute Cholecystitis

BACKGROUND

Ultrasound (US) is the first-line diagnostic study for evaluating gallstone disease and is considered the test of choice for diagnosing acute cholecystitis (AC). However, computed tomography (CT) is used widely for the evaluation of abdominal pain and is often obtained as a first abdominal imaging test, particularly in cases in which typical clinical signs of AC are absent or other possible diagnoses are being considered. We hypothesized that CT is more sensitive than US for diagnosing AC.

METHODS

A prospective registry of all urgent cholecystectomies performed by our acute care surgery service between June 2008 and January 2014 was searched for cases of AC. The final diagnosis was based on operative findings and pathology. Patients were classified into two groups according to pre-operative radiographic work-up: US only or CT and US. The US group was compared with the CT and US group with respect to clinical and demographic characteristics. For patients undergoing both tests the sensitivity of the two tests was compared.

RESULTS

One hundred one patients with AC underwent both US and CT. Computed tomography was more sensitive than US for the diagnosis of AC (92% versus 79%, p=0.015). Ultrasound was more sensitive than CT for identification of cholelithiasis (87% versus 60%, p<0.01). Patients undergoing both tests prior to surgery were more likely to be older, male, have medical comorbidities, and lack typical clinical signs of AC.

CONCLUSIONS

Computed tomography is more sensitive than US for the diagnosis of AC and is most often used in patients without typical clinical signs of AC.

Diagnosis of acute cholecystitis: value of contrast agent in the gallbladder and cystic duct on Gd-EOB-DTPA enhanced MR cholangiography

To evaluate value of %volume of contrast agent in gallbladder and contrast in cystic duct in diagnosis of acute cholecysititis with Gd-EOB-DTPA MRC obtained 60 min after contrast injection (T1-MRC60min). We included 16 acute cholecystitis (AC), 23 chronic cholecystitis (CC), and 40 healthy volunteers. Receiver operating characteristic analysis showed cutoff value of 30.5% as predictor of AC comparing with healthy volunteers (sensitivity 93.8%, specificity 100%, AUC 0.958) and cutoff of 0% as predictor of AC comparing CC (sensitivity 81.2%, specificity 82.6%, AUC 0.823). In AC absent or obliterated cystic duct on T1-MRC60min showed 81.3%, 100%, sensitivity and specificity, respectively. These can be helpful for diagnosis of AC.