Ultrasound measurements of the bile ducts and gallbladder: normal ranges and effects of age, sex, cholecystectomy, and pathologic states.

OBJECTIVE: The objectives of this study were to determine the normal values and ranges for bile duct and gallbladder measurements, adjusted for demographic data, and to assess the effects of a variety of pathologic states on these values. METHODS: Four thousand one hundred nineteen abdominal ultrasounds were retrospectively analyzed. The values for the extrahepatic bile duct (EHD), left (LIHD) and right (RIHD) intrahepatic ducts, gallbladder wall thickness, and gallbladder volume in "normal" patients were evaluated with respect to age, sex, ethnicity, and cholecystectomy status. These values were compared using multivariate analysis to those in a variety of diseased states, including cirrhosis, fatty liver, gallstones, sludge, cholecystitis, and biliary obstruction. RESULTS: One thousand four hundred eighty-four of the 4119 examinations were classified as normal. The mean EHD, RIHD, LIHD, and gallbladder wall thickness and volume measurements in normal patients were 3.8 ± 1.6 mm, 1.9 ± 1.9 mm, 1.9 ± 1.1 mm, 2.6 ± 1.6 mm, and 242 ± 234 mL, respectively.There were small increases in EHD diameter with age (+0.02 ± 0.11 mm/y, P < 0.001), female sex (+0.3 ± 1.6 mm, P < 0.0001), and cholecystectomy (+1.0 ± 1.6 mm, P < 0.0001) and a small decrease with fatty liver (-0.4 ± 1.6 mm, P = 0.0003). The gallbladder wall was thicker in patients with gallstones (+0.4 ± 1.4 mm, P = 0.0049), sludge (+0.5 ± 1.4 mm, P = 0.0019), and acute cholecystitis (+3.1 ± 1.6 mm, P < 0.0001). With biliary obstruction, the mean EHD, RIHD, LIHD, and gallbladder volume measurements were 6.0 ± 2.1 mm, 4.2 ± 1.4 mm, 4.1 ± 1.4 mm, and 171 ± 207 mL, respectively (P < 0.0001 for all values). CONCLUSIONS: This study clarifies normal values and ranges for bile duct and gallbladder measurements, adjusted for demographic data, and evaluates these measurements in a variety of common pathologic states.

Tumoral calcinosis: sonographic sedimentation sign.

We present the sonographic findings of tumoral calcinosis in two patients compared with conventional radiography, CT, and MRI. Sonography in both patients demonstrated fluid-sedimentation levels, with more echogenic debris layering dependently. This appearance has been referred to as the "sedimentation sign" on conventional radiography and results from dependent layering of hydroxyapatite crystals within cystic spaces of the lesion. There are only three reported cases in the world literature of sonographic findings in patients with tumoral calcinosis. We describe the first two cases of sonography demonstrating the "sedimentation sign," which may aid in the diagnosis of tumoral calcinosis.

Color comet-tail artifact: clinical applications.

OBJECTIVE: This article explores the circumstances under which the color comet-tail artifact occurs and illustrates the clinical value of the artifact. CONCLUSION: Subtle abnormalities on gray-scale sonograms often are better appreciated and understood when the color comet-tail artifact is present. This artifact often is helpful in situations in which gray-scale imaging does not provide adequate information for a conclusive diagnosis. Visualization of the color comet-tail artifact can improve diagnostic confidence in a wide spectrum of clinical conditions encountered in sonographic practice.

Sonography of acute pancreatitis: prevalence of findings and pictorial essay.

The purpose of this article is to describe the sonographic findings of acute pancreatitis, establish their individual prevalence, and illustrate the sonographic findings in acute pancreatitis. Prevalence of findings was determined by reviewing abdominal sonograms in 48 adult patients, derived from 71 consecutive patients who had been scanned using our standard abdominal protocol, which routinely evaluates the pancreas and peripancreatic regions. The mean anteroposterior measurement of the pancreatic body at the level of the superior mesenteric artery was 21.1 mm +/- 6.4 mm with a range of 12 to 45. Decreased pancreatic echogenicity compared with the liver was noted in 21 patients (44%). A heterogeneous echo pattern was detected in 27 patients (56%). Focal intrapancreatic regions of abnormal echogenicity were seen in 11 of 48 patients (23%). Focal masses were seen in 8 of 48 patients (17%). Hypoechoic peripancreatic areas of inflammation were seen in 29 of 48 patients (60%) and acute peripancreatic fluid collections were seen in 10 of 48 patients (21%). In this study, sonography revealed abnormalities in 45 of 48 patients (91.7%). Diffuse decreased echogenicity, focal contour, and focal echogenicity changes within the pancreas are associated with extrapancreatic disease.

Ultrasound of focal liver masses.

Detecting and characterizing focal liver lesions is one of the most difficult challenges in imaging today. All standard noninvasive imaging modalities are less sensitive than generally perceived, and characterization is imperfect. Liver sonography's main strengths are its ability to definitively characterize common benign lesions (eg, cysts and hemangiomas), safety, low cost, and its ability to guide biopsy. Sonography's weaknesses include its inability to image the entire liver in many patients and its inferiority to CT as a means of detecting extrahepatic malignant disease. Sonography is less sensitive than CT or MRI in detecting focal lesions. Ultrasound contrast agents will certainly improve liver lesion detection and characterization, but their impact is not yet clear. Typical findings in common focal liver lesions are discussed, and some hints to improve sonographic diagnosis are presented. Increased color Doppler flow should bring the possibility of hepatocellular carcinoma and focal nodular hyperplasia to mind, but Doppler diagnosis is ultimately not highly specific. Sonography, including Doppler analysis, is useful to assess the resectability of malignant masses. Intraoperative ultrasound is the most sensitive imaging modality in detecting focal liver lesions.

Ultrasonography.

Diagnostic sonography is experiencing a breath-taking period of technological advancement. Ultrasound contrast agents, new imaging techniques, and handheld instruments will play a role in facilitating more diagnostic power in high-end imaging and insuring more widespread use of diagnostic sonography in medicine in general.

Sonography of diffuse liver disease.

Sonography is often the first imaging procedure performed in the evaluation of individuals with suspected liver disease. Evaluation for biliary dilatation is always performed, because bile duct obstruction can cause abnormal liver test results, raising the suspicion of liver disease. Ultrasound is a useful but imperfect tool in evaluating diffuse liver disease. We discuss the uses and limitations of sonography in evaluating parenchymal liver disease. Sonography can show hepatomegaly, fatty infiltration of the liver, and cirrhosis, all with good but imperfect sensitivity and specificity. Sonography is of limited usefulness in acute hepatitis. Increased parenchymal echogenicity is a reliable criterion for diagnosing fatty liver. Cirrhosis can be diagnosed in the correct clinical setting when the following are present: a nodular liver surface, decreased right lobe-caudate lobe ratio, and indirect evidence of portal hypertension (collateral vessels and splenomegaly). Ultrasound plays an important role in the imaging of conditions and procedures common in patients with diffuse liver disease.

Inflammatory disease of the liver.

Imaging and imaging guided intervention have revolutionized the management of hepatic inflammatory diseases. Pyogenic abscess is preferentially treated percutaneously. Radiologic techniques are crucial for the diagnosis of amebic liver abscess and infectious conditions of the liver in immunocompromised patients.

Using contrast-enhanced helical CT to visualize arterial extravasation after blunt abdominal trauma: incidence and organ distribution.

OBJECTIVE: We evaluated the incidence and organ distribution of arterial extravasation identified using contrast-enhanced helical CT in patients who had sustained abdominal visceral injuries and pelvic fractures after blunt trauma. SUBJECTS AND METHODS: Five hundred sixty-five consecutive patients from four level I trauma centers who had CT scans showing abdominal visceral injuries or pelvic fractures were included in this series. The presence or absence of arterial extravasation, as well as the anatomic sites of arterial extravasation, was noted. We obtained clinical follow-up data, including surgical or angiographic findings. RESULTS: In our series, 104 (18.4%) of 565 patients had arterial extravasation. Of the 104 patients, 81 (77.9%) underwent surgery, embolization, or both. The combined rate of surgery or embolization in patients with arterial extravasation was statistically higher than expected at all four institutions (p <0.001). The spleen was the most common organ injured, occurring in 277 (49.0%) of 565 patients, and arterial extravasation occurred in 49 (17.7%) of 277 patients with splenic injury. Several other visceral injuries were associated with arterial extravasation, including hepatic, renal, adrenal, and mesenteric injuries. CONCLUSION: Based on the limited reports of arterial extravasation in the nonhelical CT literature, the percentage (18%) of clinically stable patients in our study with CT scans showing arterial extravasation was higher than anticipated. This finding likely reflects the improved diagnostic capability of helical CT. Although the spleen and liver were the organs most commonly associated with arterial extravasation, radiologists should be aware that arterial extravasation may be associated with several other visceral injuries.