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Color velocity imaging is a color sonographic technique that uses data contained in gray-scale B-mode image scan lines to determine blood flow velocity. We prospectively determined if color velocity imaging and power Doppler sonography can be used to differentiate acute from chronic cholecystitis. We analyzed the potential role of using these two color imaging techniques as an adjunct to conventional gray-scale sonography to differentiate acute from chronic cholecystitis.One hundred twenty-nine patients with acute right upper quadrant pain or clinically suspected cholecystitis underwent color velocity imaging and power Doppler sonography of the gallbladder as an adjunct to gray-scale sonography. Morphologic criteria were analyzed on gray-scale sonography, and the presence of flow within the gallbladder wall was assessed with color velocity imaging and power Doppler sonography. Imaging findings were compared with pathologic findings in the 50 patients who underwent cholecystectomy and with clinical and biologic findings in the 79 patients who did not undergo cholecystectomy.Twenty-two patients had surgically proven acute cholecystitis, 28 patients had surgically proven chronic cholecystitis, and 79 patients had no gallbladder disease. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of gray-scale sonography for revealing acute cholecystitis were 86%, 99%, 92%, 87%, and 97%, respectively. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of color velocity imaging and power Doppler sonography for revealing acute cholecystitis were 95%, 100%, 99%, 100%, and 99%, respectively.The accuracy of color velocity imaging and power Doppler sonography in revealing acute cholecystitis is significantly greater than the accuracy of gray-scale sonography.

Our objective was to determine the prevalence of nontumorous hepatic pseudolesions seen around the falciform ligament on dynamic spoiled three-dimensional (3D) gradient-recalled echo (GRE) MR imaging obtained during i.v. injection of a gadolinium chelate.The gadolinium chelate-enhanced spoiled 3D GRE examinations of the liver of 103 patients were prospectively analyzed by two readers for the presence of a nontumorous hepatic pseudolesion around the falciform ligament to determine the prevalence of this finding. For all pseudolesions, pathologic examination or follow-up imaging studies excluded true tumors.A total of 15 nontumorous hepatic pseudolesions were found on 13 (13%) of 103 examinations. The size of pseudolesions ranged from 5 to 15 mm (mean, 9 mm). Twelve pseudolesions were located in segment IV, and three were in segment III. On two MR examinations, two pseudolesions (one in segment IV and one in segment III) were found. Fourteen (93%) of 15 pseudolesions were seen during the arterial phase of the bolus injection. All pseudolesions (100%) were seen during the portal phase, and one pseudolesion (7%) remained visible during the equilibrium phase. The presence of true tumors was excluded in one case by pathologic examination and in twelve cases by follow-up imaging examinations.Nontumorous hepatic pseudolesions around the falciform ligament are not rarely seen on gadolinium chelate-enhanced spoiled 3D GRE examinations. Thus, recognition of these pseudolesions is crucial because they may be misinterpreted as true tumors.

common malignant tumor of the biliary tract and the fifth most common gastrointestinal malignancy in the alimentary tract after colorectal, pancreatic, gastric, and esophageal carcinomas. Earlystage gallbladder carcinoma is difficult to detect and is often an incidental finding on sonograms or CT scans. In addition. gallbladder carcinoma is not always detected during laparotomy or during videoscopic surgery and may be unrecognized until histologic examination has been performed. The prognosis of gallbladder carcinoma is still poor and radical surgical resection is, so far, the only potentially curative treatment. Determination of the best therapeutic option requires accurate tumor staging. The aim of this pictorial essay was to present the imaging features of gallbladder carcinoma at initial presentation and correlate the sonographic, CT, and MR imaging appearances of gallbladder carcinoma with surgical findings. The advantages and limitations of each technique for the diagnosis of gallbladder carcinoma and follow-up of patients who had surgery will be discussed.

Our objective was to compare the sensitivity of non-breath-hold T2-weighted fast spin-echo with and without fat suppression, breath-hold T2-weighted fast spin-echo without fat suppression, and spoiled gradient-recalled echo (GRE) MR imaging for detecting hepatic tumors using surgical findings as the standard of reference.Eighteen patients with 36 surgically proven hepatic tumors had non-breath-hold T2-weighted fast spin-echo (6000/117 [TR/effective TE; echo train length, 16) MR imaging with and without fat suppression, breath-hold T2-weighted fast spin-echo MR imaging (2700/105; echo train length, 20), and spoiled GRE images (10.1/1.9; flip angle, 30 degrees) obtained before and after injection of a gadolinium chelate. Images were analyzed separately by two independent readers, with disagreements resolved by consensus reading.Non-breath-hold T2-weighted fast spin-echo MR imaging with and without fat suppression depicted 22 (61%; 95% confidence interval [CI], 43-77%) and 20 (56%; 95% CI, 37-72%) of 36 hepatic tumors, respectively. Breath-hold T2-weighted fast spin-echo imaging allowed detection of 19 (53%; 95% CI, 35-69%) of 36 hepatic tumors. Unenhanced and gadolinium chelate-enhanced spoiled GRE images allowed depiction of 18 (50%; 95% CI, 33-67%) and 29 (81%; 95% CI, 63-91%) of 36 hepatic tumors, respectively. Gadolinium chelate-enhanced spoiled GRE images allowed depiction of significantly more hepatic tumors than any of the other pulse sequences.Gadolinium chelate-enhanced spoiled GRE imaging is more sensitive than T2-weighted MR imaging obtained with a breath-hold or a non-breath-hold technique.

The goal of our study was to compare a T2-weighted breath-hold fast spin-echo (BHSE) technique with T2-weighted non-breath-hold fast spin-echo techniques for imaging the liver.Thirty-three patients with hepatic lesions had T2-weighted BHSE images obtained in 22 sec and conventional T2-weighted non-breath-hold fast spin-echo images obtained in 3 min 12 sec with and without fat suppression. Images were analyzed quantitatively by measuring the lesion-liver contrast, spleen-liver contrast, and signal-to-noise ratios of lesions and qualitatively by evaluating the sharpness of hepatic contours, visibility of intrahepatic vessels and other segmental landmarks, and presence of artifacts.Quantitatively, lesion-liver contrast, spleen-liver contrast, and signal-to-noise ratios obtained with the BHSE technique were inferior to those obtained with fast spin-echo techniques with and without fat suppression (11.2 +/- 7.1 versus 15.4 +/- 10.6 and 14.5 +/- 9.8, p.001; 5.3 +/- 3.7 versus 8.7 +/- 3.5 and 7.0 +/- 3.8, p.001; 16.2 +/- 8.2 versus 20.1 +/- 10.9 and 19.7 +/- 9.5, p.01, respectively; Student's t test). Qualitatively, image artifacts and intrahepatic vessel depiction on BHSE images were similar to those obtained with the fast spin-echo techniques. The BHSE technique was superior to fat-suppressed fast spin-echo technique for showing hepatic contours (p.01; Wilcoxon signed-rank test).The BHSE technique is quantitatively inferior to non-breath-hold fast spin-echo techniques. However, further studies with a surgical standard of reference are needed to compare the three techniques in terms of sensitivity.

The pancreas is located deep within the retroperitoneum in the anterior pararenal space. The distal portion of the pancreatic tail extends along the course of the splenic artery and vein (Fig. 1) and enters the splenic hilum contained within the splenorenal ligament. Because of these anatomic relationships, the spleen and splenic vessels may be involved by pancreatitis. Although rare (frequency, 1-5%), splenic involvement by pancreatitis includes intrasplenic pseudocyst, abscess, hemorrhage, infarction, splenic rupture, and vascular injury. Because these complications can be life-threatening, the extent and course of the disease are closely monitored with CT to determine whether and when aggressive intervention is necessary to avoid catastrophic clinical outcomes. The purpose of this essay is to illustrate the spectrum of CT findings in cases of pancreatitis with splenic involvement.

The goals of this study were to describe variations in the intrahepatic portions of the hepatic and portal veins as visualized by helical CT during arterial portography (CTAP) and to examine the surgical implications of these findings.A retrospective review of 69 helical CTAP scans of 69 patients with small hepatic tumors and no evidence of vascular invasion or distortion was done. Axial helical CTAP scans were reviewed to determine the presence, number, and location of intrahepatic portions of the hepatic and portal veins.Among the 60 patients (87%) in whom the right, middle, and left hepatic veins were visualized, 19 (32%) had supernumerary hepatic veins. Right inferior hepatic veins were found in six (9%) of the 69 patients. Variations in intrahepatic portal anatomy were found in four patients (6%) and involved an immediate trifurcation of the portal vein in three patients (4%) and a left main portal vein originating from the right anterior portal branch in one patient (2%).Variations in the intrahepatic portions of the hepatic and portal veins are frequently seen on helical CTAP scans. Recognition of such variations is important in the preoperative evaluation of patients with hepatic tumors because these variations may have implications for tumor resection and for planning the operative approach.

A major role of imaging in the evaluation of hepatic tumors is to assist surgeons in the preoperative determination of the feasibility of hepatic resection. Although the segmental location of tumors is not the sole criterion for determining resectability, such knowledge is useful for preoperative planning of the type of resection. This essay illustrates the surgical segmental and subsegmental anatomy of the liver as shown by spiral CT during arterial portography (CTAP) with multiplanar reformation.

A prospective study was done to determine the influence of intraoperative sonographic findings on surgical decision making in patients with hepatic metastases.Thirty-seven consecutive patients with hepatic metastases who underwent surgery (for hepatic resection or intraarterial catheter placement) were prospectively evaluated. For each patient, the resectability of the metastases and the surgical approach were determined preoperatively on the basis of the combined results of sonography, bolus dynamic CT, and CT during arterial portography (CTAP). Those determinations were compared with the decisions made during surgery, which were based on the intraoperative sonographic findings. The surgical procedure that was actually performed was compared with the procedure decided on preoperatively.Eighty-two metastases were surgically and pathologically proved. Preoperatively, 73 (89%) of the 82 metastases were detected with a combination of sonography, bolus dynamic CT, and CTAP. Seventy-nine metastases (96%) were detected with intraoperative sonography. Six metastases in four patients were detected only with intraoperative sonography. Furthermore, in two patients, intraoperative sonography showed four additional metastases, which changed the initial surgical approach decided on preoperatively.Our study suggests that intraoperative sonography provides important data that cannot be obtained with preoperative imaging techniques and affect the surgical decision making in patients with hepatic metastases.

A retrospective study was performed to determine the influence of CT portography vs sonography and dynamic CT on the preoperative assessment of the resectability of hepatic metastases from colorectal cancer.Results of sonography, bolus dynamic CT, and CT portography in 28 patients who underwent surgical exploration (resection or intraarterial catheter placement) for hepatic metastases from colorectal cancer were retrospectively reviewed by two abdominal radiologists and one hepatic surgeon. For each patient, the resectability and surgical approach were decided on the basis of the results of combined sonography-bolus dynamic CT and compared with the decision made from the CT portographic results alone. The final approach suggested was compared retrospectively with the surgical procedure actually performed.Sixty-nine metastases were identified at surgery and pathologically proved. Combined sonography-bolus dynamic CT and CT portography showed 52 (75%) and 64 (93%) metastases, respectively. Twelve metastases in five patients were seen only with CT portography. In four patients, CT portography depicted additional metastases, which changed the surgical approach that had been chosen on the basis of results of sonography and bolus dynamic CT. In one patient, CT portography showed four additional metastases, precluding hepatic resection.Findings from CT portography provide vital data unattainable with sonography and bolus dynamic CT that improve the preoperative assessment of the resectability of liver metastases from colonic carcinoma.

The purpose of this study was to determine the effect of precontrast injection of papaverine hydrochloride into the superior mesenteric artery on the degree of contrast enhancement of the hepatic parenchyma during CT arterial portography (CTAP, CT with injection of contrast material into the superior mesenteric artery).Twenty-two patients were included in this study. All patients had a baseline unenhanced CT scan and then had CTAP performed with transcatheter injection of 150 ml of nonionic iodinated contrast material (30 g iodine/100 ml) at a rate of 2 ml/sec. Eleven patients received a precontrast injection of 40 mg of papaverine hydrochloride via catheter into the superior mesenteric artery, and 11 patients had CTAP without papaverine hydrochloride. Attenuation of the liver was measured before and after contrast administration in both groups of patients. For each CTAP section, the absolute hepatic enhancement (postcontrast attenuation--precontrast attenuation) and the relative hepatic enhancement ([absolute hepatic enhancement/precontrast attenuation] x 100) were calculated. Also, the mean absolute enhancement and the mean relative enhancement for the entire liver were calculated for each patient.The mean relative enhancement (+/- SD) of hepatic parenchyma was 192 +/- 54% with papaverine hydrochloride and 146 +/- 26% without papaverine hydrochloride. Relative enhancement was significantly higher when papaverine hydrochloride was used (p.02). The mean absolute enhancement (+/- SD) of hepatic parenchyma was 123 +/- 25 H with papaverine hydrochloride and 91 +/- 19 H without papaverine hydrochloride. Absolute enhancement was significantly higher in patients who had papaverine hydrochloride (p.01).The results show that precontrast transcatheter infusion of papaverine hydrochloride increases the degree of contrast enhancement of the liver during CTAP.