To analyze the CT features of solid pseudopapillary tumor of pancreas (SPTP), and correlation with the pathological findings of the disease so as to improve the diagnostic abilities, the CT images and the clinical manifestations, we retrospectively analyzed the pathological materials of 23 cases with surgery and pathology proved SPTP. In the 23 patients, 21 cases were female (91.3%) and 2 were male (8.7%). The most common symptom was abdominal discomfort with dull pain in 12 patients (52.2%). Others included the pancreatic mass that was detected incidentally during physical examination in 9 patients (39.1%), nausea/vomiting in 2 patients (8.7%). And 1 case of female patients had 2 lesions. In the 24 tumors, 6 cases were located at the head (25.0%), 3 were at neck (12.5%), 8 cases were at body (33.3%), and 7 cases were at tail of pancreas respectively (29.2%). The long-axis diameter ranged from 2.1cm to 20.1cm (mean 6.4cm). 9 tumors were mostly solid component (37.5%), 10 tumors were contained similar proportion of solid and cystic part (41.7%), and mainly cystic components in 5 tumors (20.8%). In 9 of the 23 patients, calcification was found in the tumor (39.1%). In 2 of the 23 patients, bleeding was seen in the mass (8.7%). The dilation of intrahepatic bile duct was found in 1 patient (8.7%). Liver metastasis was showed in one patient (8.7%). On post-contrast CT scan, solid parts demonstrated mild enhancement at the arterial phase. At the portal phase, solid parts were enhanced continuously in all cases, and the enhancement degrees were lower than normal pancreatic tissue. The cystic parts of all lesions showed no enhancement. Pseudo papillary structure, hemorrhage, necrosis, or cystic degeneration were found in all patients by histological study. In a word, SPTP has comparatively characteristic CT imaging features consistent with histological features, when combined with clinical manifestations, could be correctly diagnosed and differentially diagnosed.
Objective To investigate the value of the multi-detector row spiral CT (MDCT) and 3-dimensional reconstruction technique for adult intussusception. Methods Twenty-one patients with surgically and clinical following-up confirmed intussusception were retrospectively included into this study. Three patients had plain MDCT scan, 18 received contrast enhanced MDCT scan. The original images were reconstructed with multi-planar reconstruction (MPR) technique and all the images of 21 patients were divided into original image group and original image add MPR image group. Two abdominal radiologists analyzed the MDCT imaging and recorded respectively the accuracy rate and the confidence index of the doctor about following indexes: whether or not having intussusception, the location of intussusception, finding reason caused intussusception, whether or not having bowel wall ischemia and whether or not having bowel obstruction. The accuracy rate and the confidence index of the doctor were compared using a SPSS statistics software. Results The accuracy rates about above indexes between original image group and original image add MPR image group were 90.5% (19/21) vs. 100% (21/21), 81.0% (17/21) vs. 95.2% (20/21), 85.7% (18/21) vs. 90.5% (19/21), 90.9% (10/11) vs. 90.9% (10/11) and 100% (11/11) vs. 100% (11/11) respectively, and there was no significant difference between original image group and original image add MPR image group (Pgt;0.05). For following indexes: whether or not having intussusception, the location of intussusception, finding reason caused intussusception, the confidence index of the doctor between original image add MPR image group and original image group had significant difference (5.00 vs. 4.24, 4.76 vs. 4.29, 4.29 vs. 3.71), and the confidence index of the doctor of original image add MPR image group exceeded that of original image group (Plt;0.05). Conclusions MDCT plays a valuable role in diagnosis and location of intussusception, finding the reason caused intussusception and evaluation the hemodynamic impairment of being involved in bowel wall. Compared to simple axial image, axial image combine 3-dimensional reconstructed image can increase the diagnostic confidence of the doctor.
ObjectiveTo analyze the CT features of immune checkpoint inhibitor-related pneumonia (CIP) and improve the diagnostic accuracy of CIP. MethodsAmong patients with malignant tumor treated with immune checkpoint inhibitors, those who developed pneumonia and rule out other causes of disease were identified. Chest CT Imaging were reviewed to assess special signs, distribution characteristics, severity of pneumonia and radiographic patterns of CIP. ResultsA total of 28 patients were enrolled, including 26 males and 2 females. CT features include ground-glass opacity, centrilobular nodularity, reticular opacity, consolidation, traction bronchiectasis, honeycomb, etc. The lesions predominant involved peripheral lung zone (17/28), lower lung zone (18/28) and posterior lung zone (18/28), with a diffuse distribution (23/28). In most cases the disease involved both lungs (23/28), and a few involved unilateral or single lobe. The most common affected lobes were the lower lobe of the right lung (25/28) and the lower lobe of the left lung (20/28), followed by the upper lobe of the right lung (18/28). Mean pneumonia severity score was 5.5, standard deviation was 3.8, and range was 1 - 15. The most common radiographic patterns of CIP were nonspecific interstitial pneumonia (11/28) and hypersensitivity pneumonia (10/28). The second was organizing pneumonia (6/28). ConclusionsThe CT manifestations of CIP have certain specificity. Combined with the history of drug treatment and clinical symptoms of patients, the early and correct diagnosis can be obtained.
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.
Objective To investigate multi-slice spiral CT (MSCT) and MRI features of stasis cirrhosis and the diagnostic value of MSCT and MRI. Methods MSCT and MRI findings of 35 patients with stasis cirrhosis were studied. The size of liver and spleen, the diameter of hepatic vein (HV), enhancement pattern of liver parenchyma, contrast medium reflux in inferior vena cava (IVC) and (or) HV, ascites, number of varices and correlated abnormalities were reviewed. Results The volume index of liver and spleen of 35 patients was 4434.95 cm3 and 621.92 cm3 respectively. The mean diameter of HV of 27 patients (77.1%) was 3.61 cm and HV of other 8 patients (22.9%) were too small to show. Number of patients showed waves of borderline, inhomogeneous pattern of parenchymal contrast enhancement, contrast medium reflux in IVC and (or) HV, varices and ascites was 5 (14.3%), 29 (82.9%), 20 (57.1%), 16 (45.7%), and 6 (17.1%), respectively. Correlated abnormalities included cardiac enlargement 〔4 cases (11.4%)〕, pericardium thickening 〔11 cases (31.4%)〕, and pericardial effusion 〔2 cases (5.7%)〕. Conclusions Stasis cirrhosis mainly demonstrate liver enlargement, inhomogeneous pattern of parenchymal contrast enhancement, contrast medium reflux in IVC and (or) HV, and slight portal hypertension. MSCT and MRI play invaluable roles in diagnosis, differential diagnosis and etiological diagnosis of stasis cirrhosis.
Objective To achieve threedimensional (3D) contour image of boneand articular cartilage for fabricating custommade artificial semiknee joint as segment bone allograft.Methods The distal femora of human and pig were scanned with Picker 6000 spiral X-ray computed tomography with 1.0 mm thick slice. The data obtained were treated in Voxel Q image workstation for 3D reconstruction with volume rendering technique. After being downloaded to personal computer at 0.1 mm interval, the transaxial 2D image data were converted into 2D digitized contour data by using image processing software developed by the team. The 2D digitized data were inputted into image processing software of Surfacer 9.0 (Imageware Company, USA), then the 3D wire frame and solidimages of femoral condyle were reconstructed. Subsequently， based on the clinical experience and the requirement of the design of artificial knee joint, the 3Dcontour image of bone or articular cartilage was extracted from the surrounding.Results The 3D contour image of bone or articular cartilage presented was edited and processed easily for the computer aided design(CAD) of custom-madeartificial knee joint.Conclusion The 3D contour image of boneand articular cartilage can be obtained by spiral CT scanning, and the digitized data can beapplied directly to CAD of custom-made artificial joint and subsequently rapidprototyping fabricating. In addition, the reconstruction method is simple and can be applied widely to clinical implant fabricating practice of dentistry and orthopaedics.
ObjectiveTo discuss the application value of the two kinds of three dimensional reformatting techniques of spiral CT: volume rendering (VR) and maximum intensity projection (MIP) in the evaluation of children's skeletal abnormality. MethodsEighteen children with skeletal abnormality in our hospital treated between March and June 2014 were recruited in this study, diagnosed by CT transversal images and images of multiplanar reformatting (MPR). VR and MIP were made with the raw data. All three dimensional images were independently evaluated by two doctors of the Radiology Department (a score of 1-4). Images with a score of 4 were excellent. Wilcoxon signed ranks test was done for all scores and Kappa values were calculated. ResultsImages score of VR was 3.28±0.96 and of MIP was 2.89±0.90, without statistically significant difference (Z=-1.732, P=0.125). Kappa value of VR was 0.730 and of MIP was 0.593, with good and moderate consistency. ConclusionWith the special superiority of displaying spatial configuration, VR and MIP can be used to help two dimensional CT images to evaluate children's skeletal abnormality more comprehensively.
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】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.
ObjectiveTo investigate the influence of 70 kV low-dose CT perfusion technique on brain CT perfusion parameter maps and image quality. MethodsRetrospective analysis of all patients who underwent CT perfusion of brain between October 2013 and February 2014 was carried out. The patients were randomly divided into two groups according to diTherent CT examination dose: group A (80 kV, 200 mAs) and group B (70 kV, 200 mAs). All patients were scanned on a dual-source-CT (Siemens Definition Flash). Fifteen normal subjects without brain diseases in each group were selected to be studied. Region of interest (ROI) with an area of 80 mm2 was placed in the nucleus, putamen, thalamus, periventricular white matter of the frontal lobe and temporo-occipital area, and the parameters in the ROI including cerebral blood flow, cerebral blood volume, mean transit time and time to peak were detected. The carrierto-noise ratio and signal-to-noise ratio of thalamus and periventricular white matter of the frontal lobe were contrasted. The image quality of perfusion was assessed by two senior radiologists using 5 point system for blind assessment (5=best, 1=worst). The measurement of radiation dose was studied through effective dose, volume CT dose index (CTDIVOL) and dose length product (DLP). Statistical analysis was performed by independent sample t test. ResultsThere was no significant difference between group A and group B in brain CT perfusion parameters (P>0.05). There was no significant diTherence in image quality between the two groups in the objective and subjective assessment (P>0.05). In comparison with group A, the measured effective dose, CTDIVOL and DLP for group B decreased by 35%. ConclusionThere was no significant influence on the brain CT perfusion parameters and image quality using 70 kV tube voltage, and radiation dose is decreased obviously.