CT imaging of biliary enteric fistula

Background: To define the signs useful for differentiating between gallbladder–enteric fistula (GB-EF) and common bile duct–enteric fistula (CBD-EF) on computed tomography (CT) because the prognosis and management of the two are different. Methods: CT scans in 13 patients with pneumobilia, who had not had surgical biliary–enteric anastomosis and endoscopic sphincterotomy, were reviewed. The presence of fistula itself, the location of air in the biliary system, and the appearance of the gallbladder were assessed. Results: The causes of pneumobilia were GB-EF in seven patients, CBD-EF in three patients, emphysematous cholecystitis (EC) in one patient, gallbladder cancer (GBC) in one patient, and incompetent sphincter of Oddi in one patient. In three of seven GB-EF patients (43%) and in none of the three CBD-EF patients (0%), the fistula itself was detected. Air was detected in the common bile duct in four of seven GB-EF (57%) and in all three CBD-EF (100%) patients, and GBC. In six of seven GB-EF (86%) and in one of three CBD-EF (33%) patients, the gallbladder was contracted. Thus, the location of air and the contraction of gallbladder were useful signs to differentiate GB-EF from CBD-EF. Conclusion: CT can distinguish between GB-EF and CBD-EF. Received: 17 December 1996/Accepted: 5 February 1997     

Limited abdominal MRI in the evaluation of acute right upper quadrant pain

Background: We investigated whether limited abdominal magnetic resonance imaging (MRI) is as effective as transabdominal ultrasound (US) in evaluating patients presenting with acute right upper quadrant pain.Methods: Twenty-four patients underwent evaluation with a limited abdominal MRI using single-shot fast spin-echo sequences and a right upper quadrant US within 24 h. Two MRI and two US readers independently evaluated the images for gallstones, gallbladder wall thickness, pericholecystic fluid, acute cholecystitis, visualization of the common bile duct, and requests for further imaging. US and MRI findings were compared. Surgical pathology was the gold standard.Results: MRI and US demonstrated no statistically significant difference in the diagnosis of gallbladder wall thickening, the presence of gallstones or pericholecystic fluid, or the diagnosis of acute cholecystitis (p > 0.05). The sensitivity of both for acute cholecystitis was 50%, with specificities of 89% and 86% for US and MRI, respectively. US readers more frequently requested additional tests and displayed more variability in whether they could adequately see the common bile duct.Conclusion: Limited MRI is equivalent to US in diagnosing gallstones, gallbladder wall thickening, pericholecystic fluid, and acute cholecystitis in patients presenting with symptoms of acute right upper quadrant pain. Especially in sonographically challenging patients, limited MRI may provide a faster, easier method of diagnosis.     

Fascioliasis: US, CT, and MRI findings with new observations

Background: The purpose of this study is to describe the ultrasonographic (US), computed tomographic (CT), and magnetic resonance imaging (MRI) findings in fascioliasis and to emphasize the impact of radiology in diagnosis. Methods: Radiologic findings in 23 consecutive patients with fascioliasis were prospectively recorded. All patients had at least one US and CT examination, and 10 of them were studied by MRI. All diagnoses were confirmed by serologic methods. In the first three cases, initial diagnosis was reached by microscopic demonstration of the parasites' eggs in bile obtained by US-guided gallbladder aspiration. Results: In the hepatic phase of fascioliasis, multiple, confluent, linear, tractlike, hypodense, nonenhancing hepatic lesions were detected by CT. On US, the parasites could be clearly identified in the gallbladder or common bile duct as floating and nonshadowing echogenic particles. MRI showed the lesions as hypo- or isointense on T1-weighted images and as hyperintense on T2-weighted images. Conclusions: CT findings in the hepatic phase and US findings in the biliary phase are characteristic of fascioliasis. Because clinical and laboratory findings of fascioliasis may easily be confused with several diseases, radiologists should be familiar with the specific radiologic findings of the disease to shorten the usual long-lasting diagnostic process. Received: 15 December 1999/Accepted: 26 January 2000     

Segmental chronic cholecystitis: sonographic findings and clinical manifestations

Background: In chronic cholecystitis, the gallbladder (GB) wall is usually evenly involved, whereas marked segmental thickening of the GB wall (segmental cholecystitis) seldom is reported. We wanted to define its clinical manifestations and sonographic (US) findings. Methods: We reviewed the clinical and US data of 13 cases and compared these results with those of 30 patients with chronic cholecystitis with evenly thickened GB walls (usual-cholecystitis group). Results: (a) All cases of segmental cholecystitis showed the portion distal to the kinking to be markedly thickened. (b) The thickened portion corresponded to the fundus in three cases, the body and fundus in seven cases, and the fundus, body, and infundibulum in three cases; and the thickened distal portion contained many stones in 11 cases. (c) There was no difference in the maximal diameters of the GB walls between the segmental-cholecystitis group and the usual-cholecystitis group. However, there was a significant difference in the minimal diameters of the GB walls between groups. Conclusion: Knowledge of the US findings and clinical presentations of segmental cholecystitis can help in the development of appropriate diagnostic and therapeutic strategies. Received: 22 February 2001/Accepted: 21 March 2001     

Gallbladder opacification 12–24 h after angiography by CT examination: a multivariate analysis

Background: To examine the incidence and predisposing factors of gallbladder opacification in delayed computed tomography (CT) after angiography. Methods: CT examination 12–24 h after angiography was performed in 389 patients. Univariate and multivariate analyses were made. Results: Two hundred thirty-three of 389 patients (60%) revealed gallbladder opacification. Type of contrast medium (P < 0.01), total bilirubin (P < 0.01), and serum creatinine (P < 0.01) were significant and independent factors relating to gallbladder opacification. Ioxaglate (70%, relative odds = 2.86) and iohexol (63%, relative odds = 2.03) showed higher gallbladder opacification rates than that of iopamidol (45%, relative odds = 1.43) and diatrizoate (30%). Patients with a lower serum bilirubin level (relative odds = 1.67) and a raised serum creatinine level (relative odds = 2.01) showed higher incidence of gallbladder opacification. Conclusion: Gallbladder opacification after angiography is not an abnormal finding on delayed CT in patients with not only abnormal renal function but also normal hepatobiliary and normal renal function, especially for modern contrast media. Received: 13 June 1995/Accepted: 22 July 1995     

Spiral CT of the abdomen after distention of small bowel loops with transparent enema in patients with Crohn's disease

Background: To evaluate the capability of a computed tomographic (CT) technique that combines distention of the small bowel loops with a transparent enema with contrast-enhanced spiral CT of the abdomen in patients with Crohn's disease. Methods: We evaluated the abdomen with spiral CT after distention of the small bowel loops with a transparent enema of methylcellulose in 40 patients consecutively referred for radiologic evaluation of Crohn's disease of the small bowel. Fluid was infused through a nasojejunal catheter with a peristaltic pump. Ultrasonography was used to prevent bowel overdistention and detect arrival of methylcellulose to the cecum. Contrast-enhanced spiral CT of the abdomen was then performed, and the degree of contrast enhancement and the thickness of the walls of the involved loops were evaluated. A series of 10 patients with retrograde distention of the last ileal loop from large bowel water enema was used as a control. The results of the CT were compared with those of conventional radiographic small bowel studies. Results: The normal small bowel wall was 1.9–2.5 mm thick (mean = 2.1 mm); density values of the normal enhanced wall varied between 25 and 60 HU (mean = 32 HU) and presented a homogeneous structure. Bowel segments involved by the disease were 4–12.5 mm thick (mean = 9.2 mm), had density values of 75–150 HU (mean = 105 HU), and showed a multilayered appearance. Compared with conventional radiography, CT detected longer lesions or additional segments involved by the disease process in 14 cases, 11 additional fistulas, two abscesses, and mesenteric changes in 21 cases. Conclusions: The small bowel CT enema technique provides good results in the study of patients with Crohn's disease and can be used to evaluate patients with advanced lesions. Received: 24 June 1998/Revision accepted: 27 January 1999     

Dilatation of the cystic duct in patients with obstructive jaundice

Background: It is well known that obstructive jaundice causes biliary dilatation, but sonographic (US) findings of the cystic duct in patients with obstructive jaundice are rarely reported. Methods: We reviewed US findings in 25 such patients. Results: US findings of dilated cystic duct could be divided roughly into two patterns: tortuous and tubular. The former pattern was a tortuously dilated cystic duct arising from the gallbladder neck, running predominantly deeply, turning anteromedially, and then joining the posterior face of the common hepatic duct. The latter pattern was a straight dilated cystic duct running parallel with the common hepatic duct, giving the appearance of a septated bile duct. Conclusion: A better understanding of the US findings of dilated cystic duct translates into improved biliary US diagnosis.     

Contrast-enhanced ultrasonography to diagnose gallbladder perforation

Aim

The purpose of this study was to evaluate contrast-enhanced ultrasonography (CEUS) as a modality for diagnosing perforation of the gallbladder (GB) and pericholecystic hepatic abscess.

Methods

This retrospective study comprised 6 patients with acute cholecystitis and GB perforation plus pericholecystic hepatic abscess who underwent conventional US and CEUS imaging. The following sonographic features were examined: GB contour, defect in the GB wall, and pericholecystic hepatic mass. The findings of conventional US and CEUS were compared.

Results

Conventional US revealed a defect in the GB wall in 2 patients and partially obscured GB wall in 4 patients. Pericholecystic masses were visualized as isohypoechoic masses in 3 and mixed cystic-solid masses in 3 patients. Contrast-enhanced US revealed hyperenhancement of the GB wall during the early arterial phase, and a defect was seen in every patient. The pericholecystic masses showed heterogeneous enhancement with a honeycomb-like appearance during the arterial phase–interpreted abscesses.

Conclusion

Contrast-enhanced US clearly visualized defects in the GB wall and pericholecystic abscesses in patients with GB perforation. The results indicate that CEUS is a useful modality for the diagnosis of GB perforation.     

Usefulness of Ultrasound in Differentiating Xanthogranulomatous Cholecystitis from Gallbladder Carcinoma

Our study was aimed at finding the ultrasound (US) features of xanthogranulomatous cholecystitis (XGC) and evaluating the usefulness of US in differentiating XGC from gallbladder carcinoma (GBC). Through use of an electronic medical record system and the picture archiving and communication system, 31 cases of XGC and 52 cases of GBC with both sonograms and pathologic results were identified. Sonographic features of the abnormal gallbladder were evaluated. The smooth and intact interface between gallbladder lumen and mucosa was observed in most XGC cases (23/31, 74.2%) but in no GBC cases. XGC featured hyper-echoic foci, small hypo-echoic nodules and a layered appearance in the lesion, which were more frequently seen in the XGC group than in the GBC group. In conclusion, US may prove useful in the differential diagnosis of XGC and GBC, but more studies are required.     

Perforations of the rectosigmoid colon induced by cleansing enema: CT findings in 14 patients

Background: We report the computed tomographic (CT) features of colorectal perforations caused by cleansing enema. Methods: We reviewed the medical records and CT studies of all patients with colorectal perforations caused by a cleansing enema. Results: Fourteen patients (10 men, four women; average age = 80 years) were included in the study. The most common presenting symptoms were severe abdominal pain and fever. CT was performed within 48 h after the event in most patients. Extraluminal air in the perirectal fat was the most frequent finding on CT and was present in all patients. Additional findings were extraperitoneal (n = 9), intraperitoneal (n = 3) and /or subcutaneous (n = 3) air, free fluid (n = 9), extraluminal feces (n = 8), and focal bowel wall thickening (n = 4). No leak of contrast from the rectum was observed in any patient including the one patient in whom contrast was administered rectally. Ten patients were treated by surgery; five recovered and the other five died. The other four patients were treated conservatively and all four died. Conclusion: The diagnosis of colorectal perforation can be made on CT. Because the diagnosis is not always suspected by the clinician, the radiologist may be the first to suggest it. Therefore, the radiologist should be familiar with the CT features of a potentially lethal, rectally induced perforation. Received: 19 April 2001/Revision accepted: 4 July 2001     

Computed tomographic appearance of sigmoid volvulus

The computed tomographic (CT) appearance of two cases of sigmoid colon volvulus is described. Both underwent plain abdominal radiographs, contrast enema, and CT. The findings of sigmoid volvulus at CT were characteristic, having a whirl pattern of the dilated sigmoid loop around mesocolon and vessels and a bird-beak aspect of the afferent and efferent segments. CT may be valuable in a case of unusual clinical or plain film presentation as an alternative to contrast enema. Received: 24 March 1995/Accepted: 3 May 1995     

Color Doppler imaging of the gallbladder wall in acute cholecystitis: sonographic<+>–<+>pathologic correlation

Background: The purpose of this study was to evaluate the usefulness of color Doppler imaging (CDI) in suspected cases of acute cholecystitis. Methods: Twenty-two patients suspected of having acute cholecystitis were prospectively evaluated over a 12-month period using gray-scale and color Doppler technique. Gallbladder wall thickness was greater than 2 mm in all patients included in the study. Pathologic correlation was obtained in 17 patients, with clinical or sonographic follow-up in five for a period of 6<+>–/011001/months. CDI was considered positive only if the mid to fundal wall demonstrated flow. Sonographic Murphy's sign and laboratory values were recorded. Results: Eight patients had acute cholecystitis. All had positive color Doppler flow. Wall thickness in these patients ranged between 4 and 10 mm. Three patients with necrotizing acute cholecystitis had no flow within 6<+>–<+>8-mm walls. Six patients with pathologically proven chronic cholecystitis had no evidence of increased flow within thickened walls. Five patients with presumed chronic cholecystitis (thickened wall without increased color flow) were treated medically, and their symptoms resolved. CDI was more sensitive in predicting acute cholecystitis than was the sonographic Murphy's sign and/or laboratory values. Conclusion: CDI demonstrates hyperemic changes in thickened gallbladder walls and is an important adjunct in the diagnosis of acute cholecystitis. Received: 3 February 1995/Accepted: 24 March 1995     

多排螺旋CT鉴别诊断黄色肉芽肿性胆囊炎和胆囊癌

目的 探讨多排螺旋CT(MDCT)鉴别诊断黄色肉芽肿性胆囊炎和胆囊癌的价值。方法 回顾性分析经手术病理证实的11例黄色肉芽肿性胆囊炎(XGC)和20例胆囊癌(GBC)的资料,所有患者术前均接受MDCT检查,并分析两种病变的CT征象。结果 胆囊壁的增厚方式、黏膜线情况、是否有壁内低密度结节和胆道梗阻在XGC和GBC患者间差异有统计学意义(P均<0.05)。XGC与GBC患者发生邻近肝脏及周围组织改变的病例数差异无统计学意义(P>0.05),但邻近组织改变的形式不同。结论 MDCT扫描可为鉴别诊断黄色肉芽肿性胆囊炎和胆囊癌提供客观依据。     

Discrimination of gangrenous from uncomplicated acute cholecystitis: Accuracy of CT findings

In acute cholecystitis, the presence of gangrene is associated with higher morbidity and mortality and necessitates open surgical intervention rather than laparoscopic cholecystectomy. As Murphy’s sign may be absent, gangrene may not be detected ultrasonographically. This retrospective study evaluated indications of acute gangrenous cholecystitis on computed tomography (CT) in 25 patients, who were proven as having acute cholecysitis surgically and pathologically within 3 days of pre-operative CT. The CT images were reviewed by two board-certified radiologists blind to the initial CT report. Acute gangrenous cholecystitis was significantly correlated with the CT signs of perfusion defect (PD) of the gallbladder wall (P = 0.02), pericholecystic stranding (PS) (P = 0.028), and no-gallstone condition (No-ST) (P = 0.026). The presence of PD was associated with acute gangrenous cholecystitis with a relatively high accuracy (80%), a sensitivity of 70.6%, a specificity of 100%, a positive predictive value (PPV) of 100%, and a negative predictive value (NPV) of 61.5%. The combination CT signs of PD or No-ST improved the accuracy for acute gangrenous cholecystitis to 92%, with a sensitivity, specificity, PPV, and NPV of 88.2%, 100%, 100%, and 80%, respectively. Other CT signs were highly specific for acute gangrenous cholecystitis but of low sensitivity, including mucosal hemorrhage, mucosal sloughing, wall irregularity, pericholecystic abscess, gas formation, and portal venous thrombosis. CT was found to accurately diagnose acute cholecystitis, with the presence of PD, PS, or No-ST significantly correlated with that of gangrenous change. Thus, CT is useful in the preoperative detection of acute gangrenous cholecystitis.     

Gallbladder abnormalities in carcinoma of pancreatic head: findings on MR imaging

Background  Our objective is to study the gallbladder abnormalities on MR images associated with carcinoma of the pancreatic head. Methods  Thirty-six patients who had surgical resection of pancreatic head carcinoma were retrospectively analyzed regarding the appearance of the tumor and gallbladder on MR imaging performed within one month before surgery. The changes of the gallbladder wall, and the dimension of the gallbladder, cystic duct, pericholecystic region, and common bile duct (CBD) on MR imaging were noted. Results  About 92% (33/36) of patients had at least one gallbladder abnormality on MR imaging, including thickened gallbladder wall (58%), gallbladder wall striation (19%), gallbladder wall severe enhancement (44%), enlarged gallbladder (33%), gallbladder stone (19%), dilatation of cystic duct (67%), focally increased liver parenchymal enhancement adjacent to the gallbladder (19%), and pericholecystic fluid (11%). 64% of patients had dilated CBD. The diameter of the cystic duct was correlated with those of the CBD (r = 0.45, P < 0.01) and gallbladder (r = 0.56, P < 0.0001). Enlarged gallbladder, dilatation of the cystic duct, and CBD were correlated with chronic cholecystitis. Conclusion  Most patients with pancreatic head carcinoma show gallbladder abnormalities on MR imaging. Cystic duct dilatation follows CBD dilatation and is the primary cause for dilated gallbladder and chronic cholecystitis in carcinoma of pancreatic head.     

Hepatic focal nodular hyperplasia: findings on color Doppler ultrasound

Background: We assessed the color Doppler ultrasound (US) findings in focal nodular hyperplasia (FNH). Methods: Seven FNH lesions were imaged with color Doppler US and hepatic angiography. Results: In four lesions, color Doppler demonstrated a central stellate vascular appearance which correlated with central feeding artery with spoke-wheel sign angiographically. Except for one lesion, color Doppler US imaging correlated with angiographic findings. Conclusions: Color Doppler US is capable of demonstrating the typical findings of a central feeding artery and stellate vascular pattern in many cases of FNH. Received: 30 August 1995/Accepted after revision: 21 March 1996     

Spread of gallbladder carcinoma: CT evaluation with pathologic correlation

Background: To assess the accuracy of computed tomographic (CT) imaging in the detection of spread and staging of gallbladder carcinoma. Methods: CT findings of spread of gallbladder carcinoma in 59 Japanese patients who underwent radical surgery were correlated retrospectively with pathologic findings. Results: The incidence of histologically proven nodal involvement was 54% (32 patients) and the most common spread of gallbladder carcinoma. The sensitivities in CT detection of N1 and N2 nodal involvement were 36% and 47%, respectively; positive predictive values were 94% and 92%, respectively. Direct extension to the liver, extrahepatic bile duct, and gastrointestinal tract or pancreas were histologically confirmed in 24, 18, and five patients. The sensitivities in the CT detection of direct spread to the liver of less than 2 cm, more than 2 cm, the extrahepatic bile duct, and the gastrointestinal tract or pancreas were 65%, 100%, 50%, and 57%, respectively; positive predictive values were 77%, 100%, 90%, and 100%, respectively. The incidence of liver metastases and involvement of interaortocaval nodes were 7% and 16%, respectively. The sensitivities in CT detection of liver metastases and involvement of interaortocaval nodes were 75% and 21%, respectively; positive predictive values were 100% and 86%, respectively. CT could not detect direct spread to omentum and peritoneal seedings. Conclusion: For detecting the spread of gallbladder carcinoma, CT imaging has low to moderate sensitivity; however, CT imaging can help in determining resectability and in planning the treatment, especially in advanced-stage gallbladder carcinoma, because of a high positive predictive value. Received: 5 July 1995/Accepted: 8 August 1995     

Radiologically identifiable intratumoral portal vein in intrahepatic cholangiomas: a diagnostic pitfall

Background: Although intratumoral patent portal vein (ITPV) is one of the characteristic features of benign hepatic lesions, ITPVs can be demonstrated in malignant tumors. We present the spectrum of MR and CT findings of ITPV identified in intrahepatic cholangiomas with pathological correlations. Methods: The ultrasound, CT and/or MRI findings of pathologically-confirmed intrahepatic cholangiomas were reviewed and correlated with surgical specimen or autopsy findings. Results: Intratumoral patent vessels were radiographically-demonstrated in 5 patients with intrahepatic cholangiomas. All intratumoral vessels were secondary or tertiary order portal vein branches. Some wall thickening was identified on pathological examinations. Conclusion: The radiological demonstration of intratumoral portal vein is not a specific sign of benignity. In the case of a hepatic tumor with a patent portal tract, cholangioma should be considered, as well as benign tumors or lymphoma. Received: 28 February 1995/Accepted: 29 March 1995     

黄色肉芽肿性胆囊炎(附16例分析)

目的： 本文回顾性分析１６ 例黄色肉芽肿性胆囊炎 （ＸＧＣ） 的临床表现、超声特点及手术和病理结果。方法： １６ 例ＸＧＣ （男６ 例, 女１０ 例, 年龄 ４３～７８ 岁） 术前均经超声检查。结果： １６ 例ＸＧＣ 均合并胆囊结石, 胆囊壁均见增厚 ４ｍ ｍ ～１５ｍ ｍ , 其中１ 例合并肝浸润以致胆囊壁与肝实质无法分界。结论： ＸＧＣ 是一种良性慢性胆囊炎, 可能发展成胆囊癌, 尽管在组织学上具有特征, 但是在超声上无明显特异性。     

Gallstone ileus: increased diagnostic sensitivity by combining plain film and ultrasound

Background: Gallstone ileus is an uncommon cause of mechanical obstruction. Its high mortality rate can be reduced with earlier diagnosis and treatment. We wanted to determine whether ultrasound (US) performed after plain film increases the sensitivity for the preoperative diagnosis. Methods: We performed a 5-year retrospective analysis of radiologic and sonographic results of 23 patients who had surgery because of gallstone ileus. Results: Rigler's triad was identified by plain abdominal film in two patients (9%) and by US in 16 patients (69%). Plain abdominal film contributed to a definitive diagnosis in four cases and to a probable diagnosis in six cases (sensitivities of 17% for definitive diagnoses and 43% for definitive and probable diagnoses). US confirmed the diagnosis in six cases of probable gallstone ileus and provided the diagnosis in seven of 13 patients without suspected gallstone ileus based on plain abdominal film. The best results were obtained by combining plain film and US findings, with sensitivities of 74% for definitive diagnoses and 96% for definitive plus probable diagnoses. Conclusion: The preoperative diagnosis of gallstone ileus significantly increases by combining plain film and US findings. Received: 7 July 2000/Revision accepted: 4 October 2000