With the development of radiologic intervention, the treatments of aortic dissection are getting more and more diversified. In recent years, Debakey Ⅲ and DebakeyⅠaortic dissection has been usually treated with endovascular graft exclusion, or combined surgical and endovascular treatment. It is therefore more important to evaluate the aorta and its complications after interventional treatments. Because multidetector-row computed tomography (MDCT) has advantages, such as short examination time, high spatial resolution, and simple operation, this modality has become a first choice of non-invasive methods for the follow-up of aortic diseases after the intervention. Now the MDCT presentations and their anatomic-pathologic features of aortic dissection after endovascular graft exclusion or combined surgical and endovascular treatment are reviewed in this article.
【Abstract】ObjectiveTo evaluate the main CT features, the morbidity of CT signs and the anatomic-pathologic bases of secondary pyogenic peritonitis (SPP). MethodsTwentyfour patients of the SPP were retrospectively studied. Emphasis was placed on the spiral CT manifestations of the SPP correlating with their anatomic-pathologic bases and the occurrence as well as the signs of primary lesions which resulted in the SPP. ResultsThe main CT manifestations of SPP revealed as follows: the thickened peritoneum, 16 in 24 cases (66.7%), of which 14 cases were smooth and 2 cases were irregular; the ascites, 15 in 24 cases (62.5%); the free air within peritoneal cavity, 9 in 24 cases (37.5%); the edema and thickening involved in the greater omentum, 8 in 24 cases (33.3%); the small bowel mesentery, 5 in 24 cases (20.8%); and the bowels’ wall, 5 in 24 cases (20.8%); the adhesions of bowels, 6 in 24 cases (25.0%). The CT manifestation of the promary lesions, which caused SPP, and the complications were shown as follows: the signs of primary lesion, 13 cases (54.2%); the inflammatory changes in retroperitoneal cavity 13 cases (54.2%); the involvements of chest 13 cases (54.2%); and the abscess in peritoneal and pelvic cavity 6 cases (25.0%). ConclusionThe main significant CT signs of SPP could be concluded as follows: thickened peritoneum, ascites, free air within peritoneal cavity, edematous and thickened greater omentum, the small bowel mesentery, and the bowels’ wall, as well as the adhesions of bowels. So, the CT scan can present plenty of CT signs, which are significant and very helpful for making an appropriate diagnosis of SPP.
【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.
【Abstract】ObjectiveTo study the spiral CT features of gastrointestinal invasion by carcinoma of gallbladder. MethodsEight patients with surgical-pathologically documented gastrointestinal invasion by carcinoma of gallbladder were analyzed retrospectively. All patients underwent plain and contrast-enhanced dual-phase scanning of the abdomen. Oral contrast medium (1.2% Angiografin) was used to fill the gastrointestinal tract before CT scanning. ResultsThere were 2 cases of gastric antrum invasion, 6 duodenal invasion and 3 colonic invasion according to the surgical and pathological findings. Spiral CT correctly diagnosed 2 gastric invasion and 4 duodenal invasion based on several imaging features, like blurring of fat plane, focal wall thickening and luminal narrowing of involved gastrointestinal segments, and mass formation. However CT was unable to diagnose the 3 cases of hepatic flexure of colon invasion. ConclusionCT is valuable for diagnosing upper gastrointestinal tract invasion by carcinoma of gallbladder, yet the diagnosis of hepatic flexure of colon invasion is still difficult.
ObjectiveTo explore the value of multi-slice spiral CT (MSCT) in ycT stage and ycN stage evaluation of patients with locally advanced gastric cancer (cT4bN0-3M0) who underwent surgery after transformation therapy.MethodsClinical data of 32 patients with locally advanced gastric cancer (cT4bN0-3M0) in Affiliated Yantai Yuhuangding Hospital of Qingdao University form January 2017 to April 2019 were retrospective analyzed. All the patients underwent surgery after SOX regimen transformation therapy. Preoperative MSCT plain and enhanced scan were used to evaluate clinical T stage (ycT) and clinical N stage (ycN). The accuracy of MSCT scanning was evaluated by comparing with the gold standard for postoperative pathological ypT stage and ypN stage.ResultsThe accuracy of preoperative MSCT examination on ycT stage after transformation therapy was 78.1% (25/32), and that of ycN was 56.3% (18/32).ConclusionThe accuracy of MSCT in preoperative ycT stage and ycN stage after successful transformation therapy for locally advanced gastric cancer (cT4bN0-3M0) is relatively high.
ObjectiveTo analyze the influencing factors for image quality of 18F-deoxyglucose (FDG) positron emission tomography (PET)/CT systemic tumor imaging and explore the method of control in order to improve the PET/CT image quality. MethodsRetrospective analysis of image data from March to June 2011 collected from 1 000 18F-FDG whole body tumor imaging patients was carried out. We separated standard films from non-standard films according to PET/CT image quality criteria. Related factors for non-standard films were analyzed to explore the entire process quality control. ResultsThere were 158 cases of standard films (15.80%), and 842 of non-standard films (84.20%). Artifact was a major factor for non-standard films (93.00%, 783/842) followed by patients’ injection information recording error (2.49%, 21/842), the instrument factor (1.90%, 16/842), incomplete scanning (0.95%, 8/842), muscle and soft tissue uptake (0.83%, 7/842), radionuclide contamination (0.59%, 5/842), and drug injection (0.24%, 2/842). The waste film rate was 5.80% (58/1 000), and the redoing rate was 2.20% (22/1 000). ConclusionComplex and diverse factors affect PET/CT image quality throughout the entire process, but most of them can be controlled if doctors, nurses and technicians coordinate and cooperate with each other. The rigorous routine quality control of equipment and maintenance, patients’ full preparation, appropriate position and scan field, proper parameter settings, and post-processing technology are important factors affecting the image quality.
ObjectiveTo discuss the CT characteristics of combined hepatocellular carcinoma and cholangiocarcinoma (cHCC-CC), and analyze the reasons for its misdiagnosis. MethodWe retrospectively analyzed the CT data of 7 patients diagnosed to have combined hepatocellular carcinoma and cholangiocarcinoma by postoperative pathological analysis between January 2009 and February 2015. We analyzed such characteristics as location, shape, density, enhanced features, surrounding invasion, mediastinal lymph node metastasis, cirrhosis and pyoperitoneum of the disease. ResultsThere were 7 tumors among the 7 patients. Plain scan showed slightly lower density nodules or masses. After the enhancement of arterial phase, 5 tumors showed obvious inhomogeneous enhancement but 2 mild marginal enhancement. During the portal venous phase and the delay stage, the regional degree of tumor foci was significantly decreased, but some regions sustained annular or nodular and patchy enhancement. Among the 7 cases, the portal vein was invaded in 2, bile duct in 1, lymph node metastasis in 2, cirrhosis in 1, and peritoneal effusion in 1. Preoperative diagnosis was correct in only 2 cases and the other 5 cases were misdiagnosed by CT. ConclusionsThe cHCC-CC possesses some characteristic appearances on CT. Analyzing the characteristics carefully combining with symptom and cytological examination of hydrothorax can reduce the incidence of misdiagnosis.
ObjectiveTo investigate the radiological appearances of postoperative complications after living donor liver transplantation for patients with hepatocellular carcinoma under multi-detector row spiral computed tomography (MDCT) and magnetic resonance imaging (MRI) examination. MethodsThirty-nine imaging data in 20 patients with hepatocellular carcinoma after living donor liver transplantation from January 2008 to June 2010 in the West China Hospital were included and analyzed by two radiologists respectively. The relations between the types of complications and radiological appearances were especially recorded. ResultsAll the cases experienced complications to different extent. Common surgical complications occured in 20 cases, including pertitoneal fluid collection (14 cases), pneumoperitoneum (2 cases), swelling of peritoneum, omentum, and mesentery (1 case), abdominal wall swelling (2 cases), pleural effusion (9 cases), and pericardial fluid collection (2 cases). Hepatic vascular complications involved hepatic artery in 3 cases, portal vein in 5 cases. Biliary complications presented in 7 cases, including anastomotic stenosis of biliary duct (6 cases) and bile leak (1 case). Graft parenchymal complications included intrahepatic lymph retention (11 cases), infarction (3 cases), and infection (2 cases). Intrahepatic recurrence in 5 cases, intraperitoneal metastasis in 3 csses and pulmonary metastasis in 2 cases. ConclusionMDCT and MRI have important diagnostic values for postoperative complications after living donor liver transplantation for patients with hepatocellular carcinoma.
ObjectiveTo analyze the CT features of parotid tuberculosis, in order to increase the cognition and diagnostic level of the disease. MethodsNine cases of parotid tuberculosis confirmed by pathology and laboratory examinations between August 2009 and December 2012 were collected retrospectively, and we analyzed their CT features which were then compared with pathological findings. ResultsAll the 9 cases involved unilateral parotid, among which 7 were on the left side and 2 on the right side. Eight cases were parotid lymph node tuberculosis located in parotid superficial lobe, including 3 cases of single lesion and 5 cases of multiple lesions. There were 30 lesions in total with diameters ranging from 0.5 cm to 4.5 cm, presenting slightly lower density on CT scan. Twenty-five lesions were moderate homogeneous enhancement; four lesions were ring-like enhancement; and one lesion was lace-like enhancement. Six cases of parotid lymph node tuberculosis had thickened platysma, and subcutaneous fat and skin were at different levels. Six cases in the group were accompanied with enlargement of cervical lymph nodes. One case of parotid gland essence tuberculosis involved its superficial and deep lobe diffusely presenting heterogeneous slightly low density, in which we could see some patchy low density and nodular calcification. All the parotid gland essence presented diffuse enhancement with irregular liquefactive necrosis, mildly swelling of adjacent platysma and fat, without enlargement of cervical lymph node. ConclusionCT signs of parotid tuberculosis are closely related to its pathologic changes. For the lesions in unilateral parotid superficial lobe, we should consider the diagnosis of parotid lymph node tuberculosis with the signs of homogeneous enhancement, thickness of close platysma, subcutaneous fat and skin, and enlargement of cervical lymph node.
Objective To evaluate the capability of 64 multidetector CT in the differentiation between mucinous and nonmucinous gastric cancer. Methods From June 2006 to June 2007, 68 patients diagnosed as gastric cancer (18 mucinous and 50 nonmucinous cancer) underwent preoperative scan with a 64-slice helical CT scanner at West China Hospital. The CT images were analyzed retrospectively on tumor location (proximal/distal stomach), diameter of tumor, appearance of thickened gastric wall, contrast enhancement pattern (layered/nonlayered), degree of enhancement and serosal invasion. Results The primarily thickened layer (94% of patients) was the low attenuation middle layer in mucinous cancer and the rate was 72% with high attenuating inner layer or entire layer in nonmucinous cancer. The most common contrast enhancement pattern and degree was layered (83% of patients) and non-enhanced (89% of patients) in mucinous cancer and nonlayered (76% of patients) with enhanced (60%of patients) in nonmucinous cancer. The more common serosal invasion was shown in mucinous cancer than in nonmucinous cancer （89% vs 64%）. These findings were statistically significant (P＜0.05). Tumor location and size of gastric cancer were not correlated with operative pathologic classification. Conclusion Sixty-four multidetector CT is effective in distinguishing mucinous from nonmucinous gastric cancer, predominantly on the basis of thickened and layered gastric wall, enhancement pattern of low-attenuating middle layer.