Objective To investigate the CT manifestations of acute pancreatitis (AP) and its complications and to evaluate the imaging modalities for staging the severity of AP. Methods Literatures on CT manifestations of AP and its complications and severity staging of AP were reviewed.Results CT has shown an early overall detection rate of 90% for pancreatic necrosis with close to 100% sensitivity 4 days after episode. The CT severity index has shown a bly positive correlation with the development of local complications and mortality of AP.Conclusion Contrastenhanced CT is the imaging modality of choice to help detect pancreatic necrosis, stage the severity of the inflammatory processes, and depict local complications.
【Abstract】Objective To investigate the CT manifestations of chronic virus hepatitis B. Methods According to the inclusion and exclusion criteria, the clinical data and laboratory information of 120 patients with chronic virus hepatitis B were reviewed retrospectively. All patients underwent standardized contrast-enhanced spiral CT dual-phase scanning of the upper abdomen. The changes of the liver, bile duct, spleen, portal venous system, lymph node of the upper abdomen, peritoneal cavity and pleural cavity were observed and noted. Results CT manifestations of chronic virus hepatitis B were as follows: ①changes of the configuration and shape of the liver, ② changes of the density of the liver, ③intrahepatic perivascular lucency, ④thickening of gallbladder wall and edema of the gallbladder fossa, ⑤splenomegaly, ⑥enlargement of abdominal lymph nodes, ⑦ascites, ⑧abnormalities related to portal hypertension (collateral circulation), and ⑨secondary thoracic changes (pleural and pericardial effusion). Conclusion Chronic virus hepatitis B can demonstrate several abnormal findings involving the liver, gallbladder, lymph nodes, spleen, etc on contrast-enhanced CT scanning.
【Abstract】ObjectiveTo evaluate the clinical value of magnetic resonance cholangiopancreatography (MRCP) in diagnosis of extrahepatic bile duct obstruction. MethodsMRCP images of 42 patients presented clinically with obstructive jaundice were retrospectively reviewed to assess the lumen morphological abnormalities of benign versus malignant bile duct obstructions, with clinicalpathological correlation. ResultsThe bile duct of the 30 cases of benign biliary obstruction presented regular and symmetric dilation, gradual tapering,regular thickening and had a “beaklike” tip. The accuracy of MRCP for evaluating the site and the etiology of the benign biliary obstruction were 100%(30/30) and 97%(29/30) respectively. The bile duct of the 12 cases of malignant biliary obstruction presented irregular and asymmetric dilation,abrupt narrowing or iterruption,irregular thickening and had “dualduct sign”. The accuracy of MRCP for evaluating the site and the etiology of the malignant biliary obstruction were 100%(12/12) and 92%(11/12) respectively. ConclusionMRCP is the noninvasive technique of choice with excellent accuracy for the evaluation of obstructive biliary pathology.
【Abstract】Objective To investigate the appropriate reconstruction techniques of multidetectorrow spiral CT angiography (MDCTA) to depict the collateral vessels in cavernous transformation of the portal vein (CTPV) caused by tumor thrombosis of hepatocellular carcinoma (HCC). Methods MDCTA scanning was performed during the portal venous phase after intravenous contrast materials in 18 HCC patients with CTPV induced by tumor thrombosis. Raw data were reconstructed with thin slice thickness followed by 2D and 3D angiographic reconstruction methods, including maximum intensity projection(MIP), shade surface display （SSD） and volume rendering technique(VRT). Results MDCTA with MIP reconstruction accurately depicted both the tumor thrombus within the portal vein and the collateral vessels of CTPV including the biliary (cystic vein and pericholedochal veinous plexus) and the gastric (left and right gastric veins) branches. However, VRT and SSD methods did poorly in showing the tumor thrombus and the collateral vessels. Conclusion MDCTA with MIP reconstruction is the method of choice to evaluate the collateral vessels of CTPV.
Objective To retrospectively assess the importance and imaging appearance of the signal intensity， the signal noise ratio (SNR), the contrast noise ratio (CNR) and enhancement patterns of early arterial phase in diagnosis and differential diagnosis of small hepatic nodular lesions on MRI. Methods Conventional spin-echo T2W, 2D GRE T1W plain scan and Gd-enhanced 3D-VIBE multi-phasic (early arterial, late arterial and portal venous phase) acquisitions were performed for 68 consecutive patients with 102 lesions on MRI. Native T2W and 2D GRE T1W were acquired first, then 3D-VIBE fast scanning at early arterial, late arterial and portal venous phase respectively. The SNR, CNR, signal intensity and enhanced pattern of the nodular lesions appearances on plain scan and eariy arterial phase were carefully observed. Results There were hyperintense in 102 (100%) lesions in T2W and hypointense in 95 (93.1%) lesions in T1W in plain scan. There were differences among the SNR, CNR of hepatic cyst, cavernous hemangioma, neoplasm metastasis and small hepatocellular carcinoma in T2W (P＜0.05)，the highest SNR and CNR of lesions were hepatic cyst. The SNR of small hepatocellular carcinoma and the CNR of hepatic cyst were highest in all the type diseases in T1W, there was significantly difference as compared with the other type diseases (P＜0.05). The enhancement rate of small hepatic nodular lesions was 76.5% in early arterial phase. The enhancement rate of small hepatocellular carcinoma and hepatic metastasis were 100% and 87.9% respectively. The non-enhancement rate of hepatic cyst were 100%. The common enhancement patterns of early arterial phase were peripheral enhancement which were 36 lesions (35.3%). The even enhancement and uneven enhancement were 22 lesions (21.6%) and 20 lesions (19.6%) respectively. Conclusion Qualitative and quantitative evaluation of MR signal intensity combined with the enhancement patterns of early arterial phase will help for qualitation and differential diagnosis of small hepatic nodular lesions on MRI.
【Abstract】ObjectiveTo investigate the diagnostic value of the enhancement patterns for characterizing various focal hepatic lesions （FHL）. MethodsForty-seven patients (50 lesions) were included into the study. The morphologic features and the dynamic enhancement patterns of FHL were observed in the early arterial phase, late arterial phase and portal venous phase.The degree of FHL enhancement was analyzed by calculating the contrasttonoise ratio. Results70％ of the HCCs presented “fast-filling and rapid-washout” feature; 67％ of the cholangiocarcinomas showed slight enhancement in arterial phase, and 33.3％ had delayed enhancement on portal venous phase; All hemangiomas presented peripheral nodular enhancement in arterial phase, which then demonstrating centropedal “push-on” enhancement in portal venous phase; Hepatic abscesses mainly presented a slightly enhanced rim around the lesion with fibrous septa inside and an edematous zone outside. ConclusionThe enhancement pattern and the dynamic evolution of FHL enhancement had a great diagnostic value for different FHL by using MRI 3D-VIBE sequence.
【Abstract】ObjectiveTo investigate the spectrum of spiral CT imaging findings of blunt liver trauma.MethodsClinical data of 17 patients with blunt liver trauma were retrospectively collected. All patients underwent standardized spiral CT examination of the upper abdomen, which include plain scan, arterial phase and portal venous phase acquisition. The morphology, density and integrity of liver parenchyma and intrahepatic venous structures were carefully observed, as well as regions of porta hepatis, peritoneal cavity and retroperitoneal space.ResultsTwelve cases (70.6%) developed hepatic parenchymal laceration. There were 9 cases (52.9%) of traumatic hematoma, among which 5 were intraparenchymal and 4 were subcapsular. One case (5.9%) showed active bleeding within an intrahepatic hematoma, while two cases (11.8%) had injury (laceration) of hepatic veins. There were 7 patients (41.2%) who demonstrated the so-called “halo sign” around the intrahepatic portal branches. Thirteen patients were associated with peritoneal fluid (blood) collection, 3 with hematoma or hemorrhage of the right adrenal gland, 8 with plural effusion and 3 cases with rib fractures of right lower chest. ConclusionCT imaging findings of blunt liver trauma include parenchymal laceration, intraparenchymal and /or subcapsular hematomas, active hemorrhage, and tear of hepatic veins. Plain CT scan and contrastenhanced dualphase acquisition is very important for the comprehensive evaluation of patients with blunt liver trauma.
【Abstract】ObjectiveTo investigate the diagnostic value of a fast gradient-echo (GRE) three-dimensional contrastenhanced volumetric interpolated breath-hold examination (3D-VIBE) MR sequence in evaluating focal liver lesions. MethodsConventional spin-echo T2W, 2D GRE T1W plain scan and Gd-enhanced 3D-VIBE multi-phasic（early arterial, late arterial and portal venous phases） acquisitions were prospectively performed for 51 consecutive patients suspected of having focal liver lesions on CT or ultrasound imaging. Native T2W and 2D GRE T1W were acquired first, then 3D-VIBE fast scanning at early arterial, late arterial and portal venous phases respectively. The SNR and CNR of the liver lesions on plain scan and the enhancement patterns on contrast-enhanced 3D-VIBE images were carefully observed with correlation of the clinical and surgical pathological findings. ResultsThere exited certain differences in SNR, CNR, and the enhancement patterns of different kinds of focal hepatic lesions in plain scan and Gd-enhanced multi-phasic 3D-VIBE acquisitions. Conclusion3D-VIBE MR sequence is helpful in the detection and characterization of focal liver lesions.
【Abstract】Objective To investigate the imaging features of malignant invasion of major intrahepatic ductal structures (the portal and hepatic venous vasculature, the bilie duct) by primary hepatocellular carcinoma (HCC) using multidetector-row spiral CT (MDCT). Methods We retrospectively analyzed 68 documented HCC patients with tumorous invasion of the major intrahepatic ductal structures who had undergone contrast-enhanced dual-phase MDCT scanning of the upper abdomen.The morphological changes of the portal and hepatic venous vasculature, the bile duct, and the liver parenchyma at both the hepatic arterial phase and portal venous phase images were carefully observed and recorded. Results Among the 68 patients, 47 patients had malignant invasion of the intrahepatic portal venous vessels with secondary tumor thrombus formation; 12 patients had tumor involvement of the hepatic veins and intraheptic segment of the inferior vena cava; Tumor invasion of the bile duct was seen in 9 patents. The direct CT signs of tumor invasion of intrahepatic venous vessels included: ①dilatation or enlargement of the involved vein with intraluminal softtissue “filling defect”； ②enhancement of the tumor thrombus at hepatic arterial phase, the so-called “venous arterialization” phenomenon. The indirect CT signs included: ①arterial-venous shunt, ②early and heterogeneous enhancement of the hepatic parenchyma adjacent to HCC focus, ③cavernous transformation of the portal vein. The CT signs suggesting tumor invasion of the bile duct included: ①dilation of the bile ducts near or proximal to HCC lesion, ②soft-tissue nodule or mass inside the bile ducts. Conclusion Invasion of major intrahepatic ductal structures by HCC will present corresponding CT imaging features. Contrast-enhanced MDCT dualphase scanning combined with appropriate image postprocessing techniques can better evaluate the malignant invasion of major intrahepatic ductal structures.