Color velocity imaging and power Doppler sonography of the gallbladder wall: a new look at sonographic diagnosis of acute cholecystitis

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Developing a Simple Score for Diagnosis of Acute Cholecystitis at the Emergency Department

We aim to develop a diagnostic score for acute cholecystitis that integrates symptoms, physical examinations, and laboratory data to help clinicians for timely detection and early treatment of this disease. We retrospectively collected data from our database from 2010 to 2020. Patients with acute abdominal pain who underwent an ultrasound or computed tomography (CT) scan at the emergency department (ED) were included. Cases were identified by pathological, CT, or ultrasound reports. Non-cases were those who did not fulfill any of these criteria. Multivariable regression analysis was conducted to identify predictors of acute cholecystitis. The model included 244 patients suspected of acute cholecystitis. Eighty-six patients (35.2%) were acute cholecystitis confirmed cases. Five final predictors remained within the reduced logistic model: age < 60, nausea and/or vomiting, right upper quadrant pain, positive Murphy’s sign, and AST ≥ two times upper limit of normal. A practical score diagnostic performance was AuROC 0.74 (95% CI, 0.67−0.81). Patients were categorized with a high probability of acute cholecystitis at score points of 9−12 with a positive likelihood ratio of 3.79 (95% CI, 1.68−8.94). ED Chole Score from these five predictors may aid in diagnosing acute cholecystitis at ED. Patients with an ED Chole Score >8 should be further investigated.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Cystic artery velocity as a predictor of acute cholecystitis

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Surgeon-performed point-of-care ultrasound for acute cholecystitis: indications and limitations: a European Society for Trauma and Emergency Surgery (ESTES) consensus statement

BACKGROUND

Acute cholecystitis (AC), frequently responsible for presentation to the emergency department, requires expedient diagnosis and definitive treatment by a general surgeon. Ultrasonography, usually performed by radiology technicians and reported by radiologists, is the first-line imaging study for the assessment of AC. Targeted point-of-care ultrasound (POCUS), particularly in the hands of the treating surgeon, may represent an evolution in surgical decision-making and may expedite care, reducing morbidity and cost.

METHODS

This consensus guideline was written under the auspices of the European Society of Trauma and Emergency Surgery (ESTES) by the POCUS working group. A systematic literature search identified relevant papers on the diagnosis and treatment of AC. Literature was critically-appraised according to the GRADE evidence-based guideline development method. Following a consensus conference at the European Congress of Trauma & Emergency Surgery (Valencia, Spain, May 2018), final recommendations were approved by the working group, using a modified e-Delphi process, and taking into account the level of evidence of the conclusion.

RECOMMENDATIONS

We strongly recommend the use of ultrasound as the first-line imaging investigation for the diagnosis of AC; specifically, we recommend that POCUS may be adopted as the primary imaging adjunct to surgeon-performed assessment of the patient with suspected AC. In line with the Tokyo guidelines, we strongly recommend Murphy's sign, in conjunction with the presence of gallstones and/or wall thickening as diagnostic of AC in the correct clinical context. We conditionally recommend US as a preoperative predictor of difficulty of cholecystectomy. There is insufficient evidence to recommend contrast-enhanced ultrasound or Doppler ultrasonography in the diagnosis of AC. We conditionally recommend the use of ultrasound to guide percutaneous cholecystostomy placement by appropriately-trained practitioners.

CONCLUSIONS

Surgeons have recently embraced POCUS to expedite diagnosis of AC and provide rapid decision-making and early treatment, streamlining the patient pathway and thereby reducing costs and morbidity.

The utility of hepatic artery velocity in diagnosing patients with acute cholecystitis

PURPOSE

To test the diagnostic performance of elevated peak systolic hepatic arterial velocity (HAv) in the diagnosis of acute cholecystitis.

METHODS

229 patients with an ultrasound (US) performed for right upper quadrant (RUQ) pain were retrospectively reviewed. 35 had cholecystectomy within 10 days of ultrasound and were included as test subjects. 47 had normal US and serology and were included as controls. Each test patient US was reviewed for the presence of gallstones, gallbladder distention, sludge, echogenic pericholecystic fat, pericholecystic fluid, gallbladder wall thickening, gallbladder wall hyperemia, and reported sonographic Murphy sign. Demographic, clinical, and hepatic artery parameters at time of original imaging were recorded. Acute cholecystitis at pathology was the primary outcome variable.

RESULTS

21 patients had acute cholecystitis and 14 had chronic cholecystitis by pathology. For patients who went to cholecystectomy, HAv ≥100 cm/s to diagnose acute cholecystitis was more accurate (69%) than the original radiology report (63%), the presence of gallstones (51%), and sonographic Murphy sign (50%). Statistically significant predictors of acute cholecystitis included HAv ≥100 cm/s (p = 0.008), older age (p = 0.012), and elevated WBC (p = 0.002), while gallstones (p = 0.077), hepatic artery resistive index (HARI) (p = 0.199), gallbladder distension (p = 0.252), sludge (p = 0.147), echogenic fat (p = 0.184), pericholecystic fluid (p = 0.357), wall thickening (p = 0.434), hyperemia (p = 0.999), and sonographic Murphy sign (p = 0.765) were not significantly correlated with acute cholecystitis compared to chronic cholecystitis.

CONCLUSION

HAv ≥100 cm/s is a useful objective parameter that may improve the performance of US in the diagnosis of acute cholecystitis.

Derivation and validation of a practical Bedside Score for the diagnosis of cholecystitis

OBJECTIVE

We sought to develop a practical Bedside Score for the diagnosis of cholecystitis and test its accuracy against the Tokyo Guidelines (TG13).

METHODS

We conducted a retrospective study of 438 patients undergoing urban, academic Emergency Department (ED) evaluation of RUQ pain. Symptoms, physical signs, ultrasound signs, and labs were scoring system candidates. A random split-sample approach was used to develop and validate a new clinical score. Multivariable regression analysis using development data was conducted to identify predictors of cholecystitis. Cutoff values were chosen to ensure positive/negative predictive values (PPV, NPV) of at least 0.95. The score was externally validated in 80 patients at a different hospital undergoing RUQ pain evaluation.

RESULTS

230 patients (53%) had cholecystitis. Five variables predicted cholecystitis and were included in the scores: gallstones, gallbladder thickening, clinical or ultrasonographic Murphy's sign, RUQ tenderness, and post-prandial symptoms. A clinical prediction score was developed. When dichotomized at 4, overall accuracy for acute cholecystitis was 90% for the development cohort, 82% and 86% for the internal and external validation cohorts; TG13 accuracy was 62%-79%.

CONCLUSIONS

A clinical prediction score for cholecystitis demonstrates accuracy equivalent to TG13. Use of this score may streamline work-up by decreasing the need for comprehensive ultrasound evaluation and CRP measurement and may shorten ED length of stay.

Added value of point shear-wave elastography in the diagnosis of acute cholecystitis

OBJECTIVE

To evaluate the added value of point shear-wave elastography (pSWE) in the diagnostic performance of conventional US for diagnosis of acute cholecystitis.

METHODS

B-mode and colour Doppler US and pSWE were performed prospectively in 216 patients with clinically suspected acute cholecystitis. The morphology and mural vascularity of the gallbladder and median shear wave velocity (SWV) of the right liver were evaluated. Two observers independently reviewed conventional US images and subsequently reviewed combined conventional US and pSWE images.

RESULTS

Mean SWVs of the acute cholecystitis group (n = 91) were significantly higher than those of the control group (n = 85) in the right liver within 2 cm lateral to the gallbladder (1.56 versus 1.03 m/s, 1.39 versus 1.04 m/s, P < 0.0001) with a cut-off value of 1.29 or 1.16 m/s. The area under the receiver operating characteristic curve of both observers in the diagnosis of acute cholecystitis improved significantly from 0.790 and 0.777 to 0.963 and 0.962, respectively, after additional review of pSWE images (P < 0.0001). Diagnostic accuracy, sensitivity, specificity, positive and negative predictive values of combined image sets were higher than those of conventional US images alone.

CONCLUSION

Adding pSWE to conventional US improves the diagnosis of acute cholecystitis when compared with conventional US alone.

KEY POINTS

• In acute cholecystitis, stiffness of the right liver increases adjacent to the gallbladder. • The cut-off value for diagnosing acute cholecystitis was 1.29 or 1.16 m/s. • Adding pSWE to conventional US improves the diagnosis of acute cholecystitis.

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.

TG13 flowchart for the management of acute cholangitis and cholecystitis

We propose a management strategy for acute cholangitis and cholecystitis according to the severity assessment. For Grade I (mild) acute cholangitis, initial medical treatment including the use of antimicrobial agents may be sufficient for most cases. For non-responders to initial medical treatment, biliary drainage should be considered. For Grade II (moderate) acute cholangitis, early biliary drainage should be performed along with the administration of antibiotics. For Grade III (severe) acute cholangitis, appropriate organ support is required. After hemodynamic stabilization has been achieved, urgent endoscopic or percutaneous transhepatic biliary drainage should be performed. In patients with Grade II (moderate) and Grade III (severe) acute cholangitis, treatment for the underlying etiology including endoscopic, percutaneous, or surgical treatment should be performed after the patient's general condition has been improved. In patients with Grade I (mild) acute cholangitis, treatment for etiology such as endoscopic sphincterotomy for choledocholithiasis might be performed simultaneously, if possible, with biliary drainage. Early laparoscopic cholecystectomy is the first-line treatment in patients with Grade I (mild) acute cholecystitis while in patients with Grade II (moderate) acute cholecystitis, delayed/elective laparoscopic cholecystectomy after initial medical treatment with antimicrobial agent is the first-line treatment. In non-responders to initial medical treatment, gallbladder drainage should be considered. In patients with Grade III (severe) acute cholecystitis, appropriate organ support in addition to initial medical treatment is necessary. Urgent or early gallbladder drainage is recommended. Elective cholecystectomy can be performed after the improvement of the acute inflammatory process. Free full-text articles and a mobile application of TG13 are available via http://www.jshbps.jp/en/guideline/tg13.html.

TG13 diagnostic criteria and severity grading of acute cholecystitis (with videos)

Since its publication in 2007, the Tokyo Guidelines for the management of acute cholangitis and cholecystitis (TG07) have been widely adopted. The validation of TG07 conducted in terms of clinical practice has shown that the diagnostic criteria for acute cholecystitis are highly reliable but that the definition of definite diagnosis is ambiguous. Discussion by the Tokyo Guidelines Revision Committee concluded that acute cholecystitis should be suspected when Murphy's sign, local inflammatory findings in the gallbladder such as right upper quadrant abdominal pain and tenderness, and fever and systemic inflammatory reaction findings detected by blood tests are present but that definite diagnosis of acute cholecystitis can be made only on the basis of the imaging of ultrasonography, computed tomography or scintigraphy (HIDA scan). These proposed diagnostic criteria provided better specificity and accuracy rates than the TG07 diagnostic criteria. As for the severity assessment criteria in TG07, there is evidence that TG07 resulted in clarification of the concept of severe acute cholecystitis. Furthermore, there is evidence that severity assessment in TG07 has led to a reduction in the mean duration of hospital stay. As for the factors used to establish a moderate grade of acute cholecystitis, such as leukocytosis, ALP, old age, diabetes, being male, and delay in admission, no new strong evidence has been detected indicating that a change in the criteria used in TG07 is needed. Therefore, it was judged that the severity assessment criteria of TG07 could be applied in the updated Tokyo Guidelines (TG13) with minor changes. TG13 presents new standards for the diagnosis, severity grading and management of acute cholecystitis. Free full-text articles and a mobile application of TG13 are available via http://www.jshbps.jp/en/guideline/tg13.html.

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

BACKGROUND

Because of an expanded role for CT in the evaluation of patients with acute abdominal pain, it is not rare that acute cholecystitis is depicted by CT. However, the sensitivity and the specificity of a given CT variable for the diagnosis of acute cholecystitis is not known.

PURPOSE

To quantitatively and qualitatively analyze acute cholecystitis at 64-section helical CT with submilimeter and isotropic voxels using a retrospective case-control study.

MATERIAL AND METHODS

The 64-section helical CT examinations obtained with submilimeter and isotropic voxels in 40 patients with acute cholecystitis (25 men; mean age, 62.2 years) were quantitatively and qualitatively analyzed and compared to those of 40 control subjects matched for age and gender. Receiver-operating characteristic (ROC) curve analysis was used to determine the most discriminating cut-off values for quantitative variables. Comparisons of qualitative variables were made using univariate analysis.

RESULTS

Pericholecystic fat stranding, mural stratification, pericholecystic hypervascularity, spontaneous hyperattenuation of gallbladder wall, short (≥ 32-mm) and long (≥ 74-mm) gallbladder axis enlargement, and gallbladder wall thickening (≥ 3.6-mm) were the most discriminating and independent variables for the diagnosis of acute cholecystitis (P < 0.0001). Using cut-off values found at ROC curve analysis, gallbladder wall thickening, and short and long gallbladder axis enlargement were the most sensitive findings (sensitivity = 92.5%; 95%CI: 79.6%-98.4%) for the diagnosis of acute cholecystitis.

CONCLUSION

Acute cholecystitis is associated with myriad suggestive findings on 64-section helical CT. It can be anticipated that familiarity with these findings would result in more confident diagnosis of acute cholecystitis at 64-section helical CT.

Acute cholecystitis: do sonographic findings and WBC count predict gangrenous changes?

OBJECTIVE

The purpose of our study was to determine, first, if gallbladder wall striations in patients with sonographic findings suspicious for acute cholecystitis are associated with gangrenous changes and certain histologic features; and, second, if WBC count or other sonographic findings are associated with gangrenous cholecystitis.

MATERIALS AND METHODS

Sixty-eight patients who underwent cholecystectomies within 48 hours of sonography comprised the study group. Sonograms and reports were reviewed for wall thickness, striations, Murphy sign, pericholecystic fluid, wall irregularity, intraluminal membranes, and luminal short-axis diameter. Medical records were reviewed for WBC count and pathology reports for the diagnosis. Histologic specimens were reviewed for pathologic changes. Statistical analyses tested for associations between nongangrenous and gangrenous cholecystitis and sonographic findings and for associations between wall striations and histologic features.

RESULTS

Ten patients had gangrenous cholecystitis and 57, nongangrenous cholecystitis. One had cholesterolosis. Thirty patients had wall striations: 60% had gangrenous and 42% nongangrenous cholecystitis. There was no association with the pathology diagnosis (p = 0.32). There was no association between any histologic feature and wall striations (p ≥ 0.19). A Murphy sign was reported in 70% of patients with gangrenous cholecystitis and in 82% with nongangrenous cholecystitis; there was no association with the pathology diagnosis (p = 0.39). Wall thickness and WBC count were greater in patients with gangrenous cholecystitis than in those with nongangrenous cholecystitis (p ≤ 0.04).

CONCLUSION

Gallbladder wall thickening and increased WBC counts were associated with gangrenous cholecystitis; however, there was considerable overlap between the two groups. Wall striations and a negative Murphy sign were not associated with gangrenous cholecystitis.

Imaging of gastrointestinal and hepatic diseases during pregnancy

Imaging of the abdomen for suspected gastrointestinal and hepatic disease during pregnancy is assuming greater importance. Like clinical evaluation, imaging of the abdomen and pelvis is challenging but is vitally important to prevent delayed diagnosis or unnecessary interventions. Also choice of imaging modality is influenced by factors which could impact on fetal safety such as the use of ionising radiation and magnetic resonance imaging. This article discusses important issues in imaging of gastrointestinal and hepatic disease in pregnancy and the puerperium.

Flowcharts for the diagnosis and treatment of acute cholangitis and cholecystitis: Tokyo Guidelines

Diagnostic and therapeutic strategies for acute biliary inflammation/infection (acute cholangitis and acute cholecystitis), according to severity grade, have not yet been established in the world. Therefore we formulated flowcharts for the management of acute biliary inflammation/infection in accordance with severity grade. For mild (grade I) acute cholangitis, medical treatment may be sufficient/appropriate. For moderate (grade II) acute cholangitis, early biliary drainage should be performed. For severe (grade III) acute cholangitis, appropriate organ support such as ventilatory/circulatory management is required. After hemodynamic stabilization is achieved, urgent endoscopic or percutaneous transhepatic biliary drainage should be performed. For patients with acute cholangitis of any grade of severity, treatment for the underlying etiology, including endoscopic, percutaneous, or surgical treatment should be performed after the patient's general condition has improved. For patients with mild (grade I) cholecystitis, early laparoscopic cholecystectomy is the preferred treatment. For patients with moderate (grade II) acute cholecystitis, early laparoscopic or open cholecystectomy is preferred. In patients with extensive local inflammation, elective cholecystectomy is recommended after initial management with percutaneous gallbladder drainage and/or cholecystostomy. For the patient with severe (grade III) acute cholecystitis, multiorgan support is a critical part of management. Biliary peritonitis due to perforation of the gallbladder is an indication for urgent cholecystectomy and/or drainage. Delayed elective cholecystectomy may be performed after initial treatment with gallbladder drainage and improvement of the patient's general medical condition.

Flowcharts for the diagnosis and treatment of acute cholangitis and cholecystitis: Tokyo Guidelines

Diagnostic and therapeutic strategies for acute biliary inflammation/infection (acute cholangitis and acute cholecystitis), according to severity grade, have not yet been established in the world. Therefore we formulated flowcharts for the management of acute biliary inflammation/infection in accordance with severity grade. For mild (grade I) acute cholangitis, medical treatment may be sufficient/appropriate. For moderate (grade II) acute cholangitis, early biliary drainage should be performed. For severe (grade III) acute cholangitis, appropriate organ support such as ventilatory/circulatory management is required. After hemodynamic stabilization is achieved, urgent endoscopic or percutaneous transhepatic biliary drainage should be performed. For patients with acute cholangitis of any grade of severity, treatment for the underlying etiology, including endoscopic, percutaneous, or surgical treatment should be performed after the patient's general condition has improved. For patients with mild (grade I) cholecystitis, early laparoscopic cholecystectomy is the preferred treatment. For patients with moderate (grade II) acute cholecystitis, early laparoscopic or open cholecystectomy is preferred. In patients with extensive local inflammation, elective cholecystectomy is recommended after initial management with percutaneous gallbladder drainage and/or cholecystostomy. For the patient with severe (grade III) acute cholecystitis, multiorgan support is a critical part of management. Biliary peritonitis due to perforation of the gallbladder is an indication for urgent cholecystectomy and/or drainage. Delayed elective cholecystectomy may be performed after initial treatment with gallbladder drainage and improvement of the patient's general medical condition.

From the RSNA refresher courses: imaging evaluation for acute pain in the right upper quadrant

Acute cholecystitis is the most common cause of acute pain in the right upper quadrant (RUQ), and urgent surgical removal of the gallbladder is the treatment of choice for uncomplicated disease. However, cross-sectional imaging is essential because more than one-third of patients with acute RUQ pain do not have acute cholecystitis. In addition, patients with complications of acute cholecystitis, such as perforation, are often best treated with supportive measures initially and elective cholecystectomy at a later date. Ultrasound (US) is the primary imaging modality for assessment of acute RUQ pain; US is both sensitive and specific in demonstrating gallstones, biliary dilatation, and features that suggest acute inflammatory disease. Occasionally, additional imaging modalities are indicated. Computed tomography is valuable, especially for confirming the extent and nature of the complications of acute cholecystitis. Magnetic resonance cholangiopancreatography is helpful in complicated ductal disease (eg, recurrent pyogenic cholangiohepatitis) when more detailed diagnostic information is required for treatment planning, whereas endoscopic retrograde cholangiopancreatography is used when biliary intervention is required (eg, treatment of choledocholithiasis). Successful imaging with all modalities requires familiarity with both the characteristic and the unusual features of a wide variety of pathologic conditions. In addition, potential pitfalls must be recognized and avoided.

[Ultrasound of acute abdomen]

Ultrasound is an important tool in the diagnosis of acute abdominal pain, which is mainly caused by gastrointestinal diseases. This article gives an overview on the important differential diagnosis related to pain localization. Sonomorphological signs and their sensitivity and specificity are discussed. In contrast to other imaging methods ultrasound is hand guided. The present article differentiates the diagnostic capability of ultrasonic diagnosis depending on technical equipment and sonographer's educational level. These facts are important to stabilize the position of ultrasound in the ensemble of other imaging methods. The use of mobile ultrasound machines and an improved training (e.g. by computer assisted sonosimulator systems) will lead to an increasing importance of ultrasound.

Imaging benign and malignant disease of the gallbladder

This article reviews the imaging of various benign and malignant diseases of the gallbladder. Clinical findings and imaging features using ultrasound, CT, and MR for the detection and evaluation of gallstones, acute cholecystitis, xanthogranulomatous cholecystitis, adenomyomatosis, and carcinoma of the gallbladder among other disorders are discussed.

[Value of power Doppler ultrasonography with intravenous contrast medium (Levograf) in the diagnosis of acute cholecystitis]

The aim of this study was to evaluate the potential capacity of color and power Doppler sonography with intravenous contrast medium in the diagnosis of acute cholecystitis. We examined 18 patients with acute cholecystitis, 5 patients with chronic cholecystitis and a control group of 11 patients without gallbladder disease. In these patients, vascularization of the gallbladder wall was evaluated by color and power Doppler sonography before and after intravenous administration of contrast medium (Levograf). Vascularization was evaluated with a 3-point scale (grades 0, 1 and 3) according to the intensity and localization of signs of color. In the diagnosis of acute cholecystitis, basal examination with power Doppler had a sensitivity of 38.8%. After administration of intravenous contrast medium, sensitivity was 100%. In conclusion, the use of sonographic contrast media in the diagnosis of acute cholecystitis showed a sensitivity and specificity of 100%. This technique represents a viable diagnostic alternative to other complementary or imaging studies.

Imaging the patient with right upper quadrant pain

A variety of high-resolution imaging techniques are currently available for the evaluation of patients with RUQ pain. In these patients, an imaging approach that is based on identifying the presence of certain clinical signs and symptoms can aid in choosing the appropriate imaging modality and establishing the diagnosis. For patients presenting with a positive Murphy sign, sonography and biliary scintigraphy are the most useful initial imaging techniques. In patients with fever and a negative Murphy sign, a combination of sonography and contrast-enhanced CT can establish the diagnosis in most cases. And finally, in patients without fever or a positive Murphy sign, CT and MR are appropriate first-line imaging techniques.

Acute cholecystitis: CT findings

Some patients with acute cholecystitis may have symptoms suggestive of an abscess or other intra-abdominal inflammation and, therefore, may be referred for a CT of the abdomen. This report reviews the pathophysiology, clinical presentation, and CT findings of acute cholecystitis (gallstones, wall thickening, distention, pericholecystic fluid, and pericholecystic stranding). Pitfalls and complications of the diagnosis are discussed. Those scenarios where CT may prove superior to ultrasound or hepatobiliary scintigraphy are highlighted.