Objective To evaluate the prevalence rate of pulmonary malignant disease detected by low dose spiral CT in people at high risk of lung cancer. Methods Low dose spiral CT scans and chest radiographs in 300 symptom free volunteers from an on going screening study were prospectively evaluated. The study has enrolled 240 smokers, aged 45 years or older, with at least 10 pack years of cigarette smoking and 60 individuals with chronic obstructive pulmonary disease, and without previous cancer history, who were medically fit to undergo thoracic surgery. Low dose CT scans were performed with SR 7000 scanner using spiral mode, 120 kV, 50 mA, pitch 2, 5mm thickness reconstruction and Lightspeed Plus multi slice scanner using spiral mode, 120 kV, 50 mA, pitch 6 to produce 2.5 mm thick image at 2.5 mm increments. All images were assessed with cine display mode on workstation monitor. Results Non calcified nodules were detected in 56 (19%) participants by low dose CT, compared with 9 (3%) by chest radiography. Malignant disease was detected in 4 (1.3%) by CT and 3 (1%) by chest radiography. All 4 cancers were stage I. Lobar or segmental bronchial abnormalities were detected in 9 (3%) participants by CT. Among them, 3 (1%) proved to be early central lung cancer. No bronchial abnormality was detected by chest radiography. The sensitivity and specificity of cancer screening was 43% and 89%, respectively for chest radiograph, 100% and 80%, respectively for CT. The sensitivity of CT was significantly higher than that of radiograph, whereas the specificity showed no statistical difference. Conclusion Preliminary screening study indicates that low dose CT can greatly improve the likelihood of detection for small non calcified nodules and mild bronchial abnormalities, and thus of peripheral and central lung cancer at an earlier stage.

Objective To study the CT findings of early central lung cancer and correlative pathologic basis, and to evaluate the role of CT in the differential diagnosis of central lung cancer Methods Seventeen patients with early central lung cancer and 10 patients with benign lesions resembling the central lung cancer were analyzed Thin section CT was performed with a section thickness of 3 mm or 1 5 mm at Philips SR 7000 or GE Lightspeed Plus scanner The visibility of the lesions was correlated with bronchoscopic and histopathologic findings Results All 17 lesions were visualized at CT Three lesions showed focal bronchial wall thickening and internal bronchial wall irregularity, bronchial mucous coarsening, redness and swollening at bronchoscopy Fourteen lesions showed focal narrowing or obliteration of the bronchial lumen, 4 complicated with subsegmental bronchial mucoid impaction, 10 with obstructive pneumonia or atelectasis Corresponding bronchoscopic view disclosed intraluminal polypoid protrusions The epithelia were involved in 1 case, subepithelia in 5, and cartilaginous involvement in 11 according to the depth of invasion of the bronchial wall at histopathology Among 10 patients with benign lesions, 6 cases were suspected as bronchogenic carcinoma and the possibility of bronchogenic carcinoma was not excluded at CT in 4 cases There were 5 patients with uneven thickening of internal bronchial wall, 2 with lumen blood clots, 1 with lumen nodule, and no abnormalities in 2 patients at bronchoscopy Conclusion Thin section CT has been proved to be a reliable method for demonstrating the mild changes of the bronchi and to be a valuable tool for the diagnosis of early central lung cancer

Objective: To assess the accuracy of multi-slice spiral CT (MSCT) with imaging reconstruction in judging bronchial involvement from central lung cancer. Methods: MSCT was done in 30 patients who were diagnosed as central lung cancer. Images of bronchi related to lobectomy or pneumonectomy were reconstructed by means of imaging processing techniques. Then the relation between tumor and bronchus was assessed prospectively with both axial CT and CT with imaging reconstruction in comparison with subsequent pathologic and surgical findings. Results: All 30 patients underwent thoracotomy, lobectomy or pneumonectomy. Total 66 bronchi were studied. Compared with axial CT images, CT with imaging reconstruction was better in judging the relation of bronchus and tumor in comparison with subsequent pathologic and surgical findings (0.01

The B Phycoerythrin(B PE) could both be separated after crude phycobiliproteins from Porphyridium cruentum were precipitated in ammonium sulphate and dialyzed,then chromatographed on a hydroxylapatite (HA) Column and a Sephadex G 100 column respectively.The purity of B PE separated by two methods was 4.92 and 3.78 (A 545 nm/A 280 nm) respectively.When the purified B PE was electrophoresed under polyacryiamide gradient gel electrophoresis condition,only one band was observed.The B PE possessed an absorption maximum at 545nm and a room fluoresence emission at 574.5nm.

Objective To determine the value of helical CT for the follow up of patients with abdominal aortic aneurysms(AAAs) after graft implantation. Methods Twenty six patients with AAAs underwent helical CT within 3 days after graft placement. Additional follow up CT scans were obtained in 22 patients 3 months after placement. The diameter of the aneurysmal sac, complications of the procedure, position, shape, and patency of the device were recorded. Results CT scans obtained within 3 days after placement showed complete thrombosis of the aneurysm in 20 patients, and 6 patients with perigraft channels; 3 months later, of 17 thrombosed aneurysms, 9 decreased in diameter, 7 remained unchanged, and 1 increased in diameter; of 5 aneurysms with perigraft channels, 2 decreased in diameter, 2 were stable, and 1 became enlarged. 20 of 26 patients (76.92%) were successful with endovascular repaire. Conclusion Helical CT is a valuable means in follow up of the patients after endovascular repair.

Objective To demonstrate the origin of the right inferior phrenic artery(RIPA) in normal and hepatocellular carcinoma(HCC) patients and provide valuable anatomical information for angiographers before and after transcatheter arterial chemoembolization(TACE).Methods Four hundred and forty consecutive patients including 133 HCC cases who had biphase abdominal CT were assessed in this study.The routine abdominal enhanced CT scan(GE,LightSpeed16) was performed with 120 kV,200—240 mAs,10 mm collimation,1.375 pitch,and 10 mm reconstruction interval at 22—25 seconds for arterial phase triggered by timing bolus,60 seconds for portal venous phase after injection of 100 ml contrast material(300 mg I/ml) at a rate of 3.5 ml/s.Multiplanar reconstruction(MPR) and maximum intensity projection(MIP) images were generated using 1.25 mm images reconstructed with 1 mm interval in arterial phase and reviewed by two radiologists.An enhanced artery medial-posterior to the IVC,originated from aorta or its branches to the diaphragmatic dome was interpreted as the RIPA.Results The RIPA was showed in all(440 patients)(100%).Among 218(49.5%) RIPAs originated from the aorta,140 were from the right side of the aorta,22 from the left side of the aorta,56 from the anterior wall of the aorta,36 RIPAs had the same origin with the left inferior phrenic artery.Among 138(31.4%) RIPAs from the celiac artery,10 RIPAs had the same origin with the left gastric artery,and 33 RIPAs had the same origin with the left inferior phrenic artery.78(17.7%) were from the right renal artery,6(1.4%) were from the left gastric artery(the left gastric artery from aorta).The dilatation of the RIPA was demonstrated in 16 of(133 hepatocellular) carcinoma patients.Conclusion Multislice helical CT could demonstrate the origin of the RIPA in arterial phase and provide useful anatomical information for angiographer before and after TACE.

0.05) and CT values of mesenteric panniculitis on unenhanced scan were significantly higher than those of the same patients′retroperitoneal fat(-91——115 HU)(P

Objective To evaluate the efficacy of multislice helical CT(MSCT) in the diagnosis of coronary artery disease Methods 30 patients were studied with MSCT CT data were reconstructed to demonstrate the abnormalities of coronary artery and the results were compared with that of angiography Results In patients with heart rate less than 60 BPM, there was no difference to show the main branch of left coronary artery and left descending artery compared with more than 60 BPM( P =0 197 and 0 128,Fisher′exact);and obvious differences in showing left circumflex artery (? 2=5 88, P

Objective To present the multislice helical CT (MSCT) and chest radiographic findings of congenital bronchial atresia (CBA) in order to improve the diagnosis of CBA.Methods Eleven patients with CBA, who had histological results in 3 cases, bronchoscopy in 6 cases and more than 1 year follow-up in 2 cases, underwent MSCT with 10 mm slice thickness. 1.25 mm thickness images with 1 mm reconstruction interval were performed on 16-slice helical CT, and multiplanar reconstruction (MPR), maximum intensity projection (MIP) and minimum intensity projection (MinIP) were made at a dedicated workstation. The involved segment of lung, shape of bronchocele and hyperinflation around bronchocele were recorded. Results On CT findings, all 11 patients demonstrated bronchocele and peripheral emphysematous changes which were shown in 8 cases on chest radiographs. An air-fluid level within the bronchocele was seen in 3 cases by MSCT and 2 by chest radiographs. The segmental bronchus was affected in 10 cases and the subsegmental in 1 case. 3 CBAs were in the left and 8 in the right. 6 patients with CBA presented a rounded, branching opacity emanating from the hilum and 5 were seen as a peripheral nodule. Conclusion The presence of a bronchocele and surrouding emphysematous change is the typical radiologic finding of CBA. MSCT can provide more information than X-ray chest radiograph for the diagnosis of CBA.

Objective To evaluate the visualization of the anterior spinal artery (ASA) and the artery of Adamkiewicz (AKA) as well as the affecting factors for the detection rate using multidetector row CT (MDCT). Methods Ninety-nine consecutive patients (31 women and 68 men; age range, 25-90 years; average age 61.3 years) with suspicion for thoracic aortic lesions necessitating surgical intervention (31 aortic aneurysm, 45 dissection, 5 intramural hematoma, and 18 normal), underwent 16-slice MDCT angiography from the aortic arch to the aortic bifurcation. Transverse sections, multiplanar reformations (MPR) and thin maximum intensity projections (MIP) were used to assess the ASA and AKA. The level of the ASA and AKA origins and CT acquisition parameters were recorded. The contrast-to-noise ratio (CNR) of the image, an index of the mass of the T11 body (vertebral mass index), the subcutaneous fat thickness,and the CT value within the aortic arch and at the T11 level were measured. The detection of the ASA and AKA was evaluated relative to the acquisition parameters, scan characteristics, and aortic lesion type. Differences were assessed with Wilcoxon rank-sum and t tests. Results The ASA was visualized in 51 patients (52%) and the AKA in 18 patients (18 %). The ASA was identified in 36/67 (54%)patients with 1.25 mm thickness and in15/32 (47%) patients with 2.5-3.0 mm thickness. This difference did not achieve significance (P=0.13). The detection rate of the ASA and the AKA was influenced by vertebral mass index and the CNR (P＜0.05). The amount of subcutaneous fat affected the detection rate of the ASA (P＜0.05) but not the AKA. In CT scans with ASA detection, the mean CT values in the aorta at the arch and at T11 were 360 and 358 HU, respectively; whereas in CT scans without ASA detection, the CT values in the aorta at the arch and at T11 were lower (297 and 317 HU, respectively; both P＜0.05). Conclusion The ASA and AKA were less frequently detected in our cohorts than previous reports. The visualization of the ASA and AKA was significantly affected by aortic enhancement, the vertebral mass index, and the CNR.