Objective To clarify the thin-layer 16-slice spiral CT features of coal worker’s pneumoconiosis and the superior distribution of comorbidities in their staging and lobes and lung field anatomy. Methods Sixty-six patients with coal worker's pneumoconiosis diagnosed by the pneumoconiosis diagnosis and identification group from October 2014 to March 2015 were enrolled. All patients underwent 16-slice spiral CT and thin-layer CT reconstruction with a thickness of 1.5 mm. The thin-slice CT signs and comorbidities of coal workers’ pneumoconiosis were observed, and the superior distribution of CT signs in patients at different stage and different lobes and lung field anatomy were evaluated. Results There were 16 cases of irregular small nodules in the lungs, 22 cases of large shadow fusion, 18 cases of intraocular shadow calcification, 41 cases of emphysema, 21 cases of pulmonary bullae, 21 cases of pulmonary hypertension, and 31 cases of enlarged lymph nodes in the mediastinum and calcified. The above signs were mostly distributed in stage Ⅲ pneumoconiosis (P<0.05). There were 32 cases of regular small nodules, which were mostly distributed in stage Ⅰ pneumoconiosis. In the 16 cases of irregular small nodules, the advantage was distributed in the middle and outer lobes of the double lungs. In the 22 cases of large shadow fusion, the advantage was distributed in the upper and lower lobe of the lungs. In the 16 cases of tuberculosis, the advantage was distributed in the upper lobe of the lungs. In the 21 cases of bullous bullae, the advantage was distributed in the upper lobe of the two lungs, mostly in the right upper lung. Conclusion The thin 16-slice spiral CT signs of coal worker’s pneumoconiosis can reflect the pathological changes, and have a certain correlation with the stage of pneumoconiosis, and have obvious characteristics in the anatomical distribution of lung and lung fields.
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.
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.
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 discuss the value of 64-slice spiral CT （MSCT） in diagnosis of gastric stromal tumor （GST）. Methods Thirty-two patients proved GST by surgery and pathology from May 2010 to August 2011 in West China Hospital, Sichuan University were classified by Fletcher malignancy degree classification，the CT features including the location，size，boundary，shape，density，growth pattern，metastases，and enhancement and its relationships to GST malignancy degree were analyzed retrospectively. Results All 32 cases were single lesion，the accuracy of CT in localization was 100%. Nine cases were intra-luminal，10 were extra-luminal，and 13 were both intra- and extra-luminal growth. Nine cases were in low degree group，with diameter＜5cm，round or oval in shape，clear border, homogenous density and enhancement （7/9）；Twenty-three cases were in high degree group，with diameter ≥5cm in 19 cases，irregular in shape and indistinct bourdry （18/23），heterogeneous density （20/23） with necrosis，ulcer was seen in 6 cases. Three cases in high malignance degree group showed pancreas and spleen involvements，2 cases of left diaphragm involvement，1 of omentum metastasis，2 of liver metastases，and 1 of lymph node metastasis. Conclusions MSCT is the optimal method to exam GST，there is correlation between the CT features and malignancy degree，MSCT is helpful for analyzing malignancy degree preoperation.
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.
Objective To investigate the CT manifestation and clinical significance of the gastrointestinal tract involvement in acute pancreatitis (AP). Methods Two hundreds CT scans in 131 patients with acute pancreatitis between Jan. 1, 2009 and Jun. 30, 2009 were included into the study. Two radiologists analyzed the images retrospectively, paying attention to the CT features of the gastrointestinal tract involvement, such as the style, distribution, and so on. The correlation between gastrointestinal tract involvement and CT severity index, clinical severity grading, and turnover of acute pancreatitis were studied using a SPSS 14.0 for windows statistics software. Results The CT images in 109 (83.2%) patients showed gastrointestinal tract involvement, which distributing mainly stomach, duodenum, jejunum, and transverse colon, and showing mainly the gastrointestinal tract wall thickening and distension. The gastrointestinal tract involvement had positive correlation with CT severity index, clinical severity grading, and turnover of acute pancreatitis (r=0.689， P=0.000; r=0.584， P=0.000; r=0.346， P=0.000). Conclusions The gastrointestinal tract involvement is common complication in acute pancreatitis and concerns with severity and prognosis of the disease. As other extrapancreatic organs involvement, the gastrointestinal tract involvement has important value for severity assessment, prognosis evaluation, and therapeutic effect monitoring of acute pancreatitis.
ObjectiveTo investigate the value of rectumaerated MSCT examination in diagnosis of mesorectal infiltration of rectal cancer and lymph node metastasis staging. MethodsFrom January 2010 to July 2010, the data of 68 patients with rectal cancer confirmed by pathology were analyzed in the First Affiliated Hospital of Liaoning Medical University. All the patients underwent rectumaerated MSCT preoperatively and postoperative pathology was taken as the gold standard for evaluation of the accuracy, sensitivity, specificity, positive or negative predictive values of MSCT in diagnosis of mesorectal infiltration and lymph node metastasis.ResultsIn rectum-aerated MSCT scanning, rectum and sigmoid colon was fully expanded, perirectal fat space was clear between perirectal fat space and relatively high density rectal wall and very low density enteric cavity. For mesorectal infiltration of degree Ⅰ, Ⅱ, and Ⅲ, the accuracies were 92.6%（63/68）, 91.1%(62/68), and 95.6%(65/68), respectively; sensitivities were 91.2%(31/34), 85.0%(17/20), and 92.9%(13/14), respectively; specificities were 94.1%(32/34), 93.8%(45/48), and 96.3%(52/54), respectively; positive predictive values were 93.9%(31/33), 85.0%(17/20), and 86.7%(13/15), respectively; negative predictive values were 91.4%(32/35), 93.8%(45/48), and 98.1%(52/53), respectively. For lymph node metastasis in N0, N1, and N2, the accuracies were 92.6%(63/68）,85.3%(58/68）, and 92.6%(63/68）, respectively; sensitivities were 86.2%(25/29), 90.0%(27/30), and 66.7%(6/9), respectively; specificities were 97.4%(38/39), 81.6%(31/38), and 96.6%(57/59), respectively; positive predictive values were 96.2%(25/26), 79.4%(27/34), and 75.0%(6/8), respectively; negative predictive values were 90.5%(38/42), 92.1%(35/38), and 95.0%(57/60), respectively. ConclusionsRectumaerated MSCT scaning can clearly show the depth of rectal carcinoma infiltration in the mesorectum, and N staging of mesorectal lymph node metastasis of MSCT has a higher consistency with that of pathological staging. Rectumaerated MSCT scanning is an important referenced method for clinical preoperative staging and individualized chemotherapy regimen.
【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 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.