Sparse-view helical CT reconstruction based on tensor total generalized variation minimization / 南方医科大学学报

OBJECTIVE@#We propose a sparse-view helical CT iterative reconstruction algorithm based on projection of convex set tensor total generalized variation minimization (TTGV-POCS) to reduce the X-ray dose of helical CT scanning.@*METHODS@#The three-dimensional volume data of helical CT reconstruction was viewed as the third-order tensor. The tensor generalized total variation (TTGV) was used to describe the structural sparsity of the three-dimensional image. The POCS iterative reconstruction framework was adopted to achieve a robust result of sparse-view helical CT reconstruction. The TTGV-POCS algorithm fully used the structural sparsity of first-order and second-order derivation and the correlation between the slices of helical CT image data to effectively suppress artifacts and noise in the image of sparse-view reconstruction and better preserve image edge information.@*RESULTS@#The experimental results of XCAT phantom and patient scan data showed that the TTGVPOCS algorithm had better performance in reducing noise, removing artifacts and maintaining edges than the existing reconstruction algorithms. Comparison of the sparse-view reconstruction results of XCAT phantom data with 144 exposure views showed that the TTGV-POCS algorithm proposed herein increased the PSNR quantitative index by 9.17%-15.24% compared with the experimental comparison algorithm; the FSIM quantitative index was increased by 1.27%-9.30%.@*CONCLUSIONS@#The TTGV-POCS algorithm can effectively improve the image quality of helical CT sparse-view reconstruction and reduce the radiation dose of helical CT examination to improve the clinical imaging diagnosis.

Influence of multi-slice spiral CT combined with plasma CA199,CA50 and CA242 levels detection on diagnostic accuracy of pancreatic cancer / 国际检验医学杂志

Objective To explore the influence of Multi-slice spiral CT combined with plasma carbohydrate antigen 199 (CA199) ,carbohydrate antigen 242 (CA242) ,carbohydrate antigen 50 (CA50) levels detection on diagnostic accuracy of pancreatic cancer .Methods 77 cases of patients with pancreatic lesion treated in our hospital were studied ,and all were confirmed by surgery ,there were 48 cases of pancreatic carcinoma ,29 cases of pancreatic benign diseases .All the patients were undergoing CT testing .Plasma CA199 ,CA50 and CA242 levels were detected by using Radioimmunoassay method ,and plasma CA199 ,CA50 ,CA242 levels ,CT test re-sults ,and the efficacy of single test diagnosis were contrasted .Results After CT diagnosis ,there were 8 cases positive in the benign group ,39 cases positive in the pancreatic cancer group ,with the overall positive rate of 61 .04%,and the coincidence rate was 77 .92% when compared with the operation and pathological results . Plasma CA199 ,CA50 and CA242 in the pancreatic cancer group were higher than those in the benign group , the difference was statistically significant (P＜0 .05) .Surgical pathological diagnosis was as the gold stand-ard ,the coincidence rate of CA199 was 75 .32% in the highest ,and the coincidence rate of CA242 was 45 .75%in the lowest .Compared with those in the single plasma CA199 ,CA50 ,CA242 detection ,the accuracy and sen-sitivity of combined diagnosis ,and missed diagnosis rate decreased ,the difference was statistically significant (P＜0 .05) .Those were slightly higher than those of CT detection ,but without statistically significant differ-ence (P＞0 .05) .There was no significant difference in specificity and misdiagnosis rate among different diag- nostic ways (P＞0 .05) .Conclusion The accuracy and sensitivity of multi-slice spiral CT is higher in diagnosis of pancreatic cancer ,but combined detection of plasma CA199 ,CA50 and CA242 can further improve diagnosis efficiency ,and provide a reference for clinical treatment of pancreatic cancer .

Comparison of contrast-enhanced ultrasound and contrast-enhanced helical computed tomography in diagnosis of hepatocellular carcinoma / 天津医药

Objective To compare the diagnostic value of contrast-enhanced ultrasound (CEUS) and contrast-enhanced helical computed tomography (CECT) for hepatocellular carcinoma (HCC) with liver cirrhosis. Methods Two hundreds and forty-one focal liver lesions in 207 patients with Hepatitis B virus (HBV) cirrhosis were detected with CEUS and CECT, respectively. Pathological results were used asgold standardto compare the two methods. Diagnostic results of the two methods were compared with pathological results. Differences were assessed using the McNemar test, and the Kappa test was used for consistency evaluation. Results (1) For 113 liver lesions that were ≤2 cm, the number of HCC lesions was 63, and the number of benign lesions was 50. There were no significant differences in results of CEUS and CECT compared with that of the gold standard of McNemar test results (P = 0.824, P = 0.082). Consistency of the Kappa test results of CEUS and CECT in comparison with the gold standard was general (Kappa = 0.643, Kappa = 0.421). The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of HCC diagnosed by CEUS were higher than those of CECT. The rate of arterial enhancement was better for CEUS [87.30% (55/63)] than that for CECT [69.84%(44/63),χ2=5.704, P=0.017]. (2) For 128 liver lesions that were>2 cm, the number of HCC lesions was 77, and the number of benign lesions was 51. There were no significant differences in the diagnostic results between McNemar test and CEUS and CECT tests (P = 0.481, P = 0.167). Consistency of the Kappa test results of CEUS and CECT and gold standard was general (Kappa = 0.710, Kappa = 0.697). The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of HCC were not different between two diagnostic methods. The rate of arterial enhancement was 89.61%(69/77) for CEUS and 85.71%(66/77) for CECT, and there was no significant difference between the two groups (χ2=0.540, P=0.462). Conclusion For HCC≤2 cm, the diagnostic performance of CEUS is better than that of CECT. For HCC>2 cm, the diagnostic performance is similar for the two diagnostic methods.

Spatial resolution evaluation of 64-slice helical computed tomography / 医疗卫生装备

To put forward spatial resolution detection requirements of 64-slice helical CT based on analyzing the present situation of CT spatial resolution detection. The requirements for spatial resolution in the existing industrial standards were analyzed, and some test data were used to prove the deficiency of the standards. Spatial resolu-tion detection requirements were proposed for 64-slice helical CT, and the factors affecting spatial resolution were ex-plored. The deficiencies in the original standards were eliminated. The proposed requirements may facilitate the spatial resolution detection of 64-slice CT, and thus can enhance image quality for clinical diagnosis and treatment.

Aspectos tomográficos da coluna cervical de equinos / Tomographic imaging of the cervical spine of horses

Descreveu-se a anatomia da região cervical de equinos adultos, com base em imagens obtidas no exame de tomografia computadorizada helicoidal realizado em peças anatômicas de equinos adultos. A tomografia computadorizada foi o método de imagem diagnóstica de escolha e possibilita as reconstruções de imagens tridimensionais e em outros planos anatômicos, como sagital e coronal. Todas as imagens foram adquiridas e avaliadas em filtro e janela para tecido ósseo. Observaram-se diferenças anatômicas e as particularidades normais das vértebras, principalmente da região occipitoatlantoaxial, a qual apresenta maior incidência de alterações.

The anatomy of the cervical spine of mature horses based on images obtained with a helical computed tomography examination performed on anatomic specimens was studied. Computed tomography was the diagnostic imaging method of choice and allowed three-dimensional reconstructions of images and other anatomical planes, such as coronal and sagittal. All images were acquired and evaluated in the filter and window to bone tissue. It was possible to demonstrate the anatomical differences and peculiarities of the normal vertebrae, particularly the occipito-atlantoaxial region, which has a higher incidence of changes to assist in the visualization of any change of the bone pattern on CT studies.

Predetermination of structure surrounding duodenal papilla before EST by multi-slice spiral CT / 中华消化内镜杂志

Objective To study the predetermination value of multi-slice spiral CT for showing the major blood vessels,bile and pancreatic ducts around normal duodenal papilla before EST.Methods A 16-slice spiral CT was used to perform 28s and 68s enhanced scan for normal structures surrounding duodenal papilla in 30 subjects.Post-processing was done to the raw data with thin-slice maximum intensity projection (TSMIP) and thin-slice average intensity projection (TSAIP),and then the structure of bile and pancreatic ducts,duodenal artery and pancreatic-duodenal conjunction were reconstructed.The reconstructed images were double-blind evaluated.Distances between papilla and upper,front,and behind edge of the pancreatic-duodenal conjunction,situation of the duodenal papilla artery and the distance from the papilla artery end to the papilla were recorded.Results After dual-phase enhanced scan,the post-processing results for the images of the surrounding structure of pancreatic and duodenal papilla were stable and the results of double-blind evaluation were consistent.Image scores of the arteries surrounding duodenal papilla and pancreatic duct at 28th second were significantly higher than those of 68th second,whereas bile duct and the ampulla structure image scores of 68th second were higher.TSMIP of local vascular structure could display anterior-superior pancreatic-duodenal artery (ASPDA) in 93.3％ of the subjects,posterior-superior pancreatic-duodenal artery (PSPDA) in 73.3％,inferior pancreatic-duodenal artery (IPDA) in 73.3％,duodenal-papillary artery (DPA) in 56.7％,bile duct in 96.7％,pancreatic duct in 90.0％ aud pancreatic and duodenal parenchima in 100.0％.The DPAs all started from PSPDA origin and down to papilla,with only 2 cases of 30 (6.7％) reached the upper edge of the duodenal papilla.Others showed arteries turned thin obviously at 12 mm above the papilla; the normal common bile duct can be tracked to the opening of the papilla.The Coronal Oblique TSAIP imaging showed the distance from the duodenal papilla-bile duct ending to the lower edge of the pancreatic-duodeual upper conjunction was 15.7±1.9 mm.Distance from papilla to the front edge of pancreatic-duodenal conjunction was 16.6±3.2 mm and to the behind edge was 1.7±0.4 mm.Distance (depth) from the inner edge of the papilla to the bile-pancreatic conjunction was 8.0±1.7 mm.Conclusion The 3D reconstruction of the Multi-slice spiral enhancement CT Imaging can providc high quality images of relative vascular,bile-pancreatic and obvious surrounding structures to the forthcoming operation.Massive hemorrhage and perforation risks of EST can be evaluated based on the vascular distribution and directions around duodenum and pancreas and the bile duct imaging.

The Comparison of Usefulness between MDCT Angiography and DSA in the Diagnosis of Intracranial Aneurysm / 의학물리

The purpose of this study was to compare the image between DSA and MDCT Angiography and to examine whether MDCT Angiography could be useful as a screening test for the diagnosis of cerebral aneurysm in patients who were diagnosed with cerebral aneurysm on DSA. Of patients who were diagnosed with cerebral aneurysm DSA at University Hospital, 194 patients who concomitantly underwent MDCT Angiography were enrolled in the current retrospective study. The methods for analyzing cerebral aneurysm were to analyze the presence of cerebral aneurysm on DSA and MDCT Angiography. In cases in which it exceeded 1, the corresponding cases were classified as narrow-neck aneurysms. In otherwise cases, they were classified as wide-neck aneurysms. Thus, a comparative analysis could be performed to ascertain if cases were narrow-neck or wide-neck aneurysms. As compared with DSA, the sensitivity of MDCT Angiography for cerebral aneurysm was measured to be 97.4%. The degree of consistency between narrow-neck and wide-neck aneurysms was 90.2% and the proportion of undetectable an at MDCT Angiography was 2.54%. mean size was 2.4 mm. It is expected that a non-invasive diagnostic modality for a screening test for cerebral aneurysm, MDCT Angiography might be a very useful regimen as compared with an invasive one, DSA.

Image features of helical CT in advanced schistosomiasis cirrhosis / 中国血吸虫病防治杂志

The abdominal CT findings of cirrhosis of advanced schistosomiasis in 262 cases were analyzed.All the cases had the calcification in liver in varying degrees,hypodense structure in junction areas and blood vessel in centre,calcification in portal vein system,calcification of colon and so on.The characteristics of CT performance can provide the evidence for defferential diagnosis.

Preoperative Assessment of Vascular Invasion in Pancreatic Cancer——Value of CT / 中国普外基础与临床杂志

Objective To probe CT grading criteria of vascular invasion in pancreatic cancer.Methods Retrieved articles in CNKI and PubMed about value of CT in preoperative assessment of vascular invasion in pancreatic cancer last ten years.Results Multislice helical CT is considered the best imaging method to assess the invaded peripancreatic vessels in pancreatic cancer.There are different CT criteria of vascular invasion in pancreatic cancer based on extension of hypodense tumor and its relation to blood vessels,on the degree of circumferential contiguity of tumor to vessel,on the degree of lumen stenosis,and on the degree of contiguity between tumor and vessels combined vascular caliber.Conclusion CT grading criteria are not uniform,each one has defects.

Endoscopic ultrasonOgraphy and CT in preoperative TN staging of esophageal cancer / 中华消化内镜杂志

objective To retrospectively evaluate the accuracy of endoscopic ultrasonography (EUS)and CT in preoperative tumor,and nodal metastasis(TN)staging of esophageal carcinoma.Methods TN stages of 87 cases diagnosed with preoperative EUS and CT were compared with postoperative pathological results.No patient underwent radiotherapy or chemotheraphy.The radial echoendoscope was used,and balloon dilation was required in 5 cases with stricture.Results The total accuracy of T staging with EUS was 85.1%.CT could not differentiate Tl from T2.The sensitivity of EUS for N staging was 85.0%,higher than that of CT(60.8%).However,some lymph nodes which were not detected by EUS could be revealed by CT.Accuracy of EUS plus CT in T staging is 85.1%.and that in N staging is 90.8%.Conclusion EUS is the most accurate measure in assessing the depth of tumor invasion,whereas the combination of EUS and CT is capable of an overall evaluation for TNM staging.

Multi-slice spiral CT 3D reconstruction of extrahepatic feeding arteries in hepatocellular carcinoma:its clinical applications / 介入放射学杂志

Objective To discuss the feasibility of displaying the extrahepatic feeding arteries in hepatocellular carcinoma with the help of multi-slice spiral CT 3D reconstruction and to assess the clinical value of this technique. Methods Triple-phase enhanced CT scanning with a 64-slice spiral CT scanner was performed in 89 patients with advanced primary hepatocellular carcinoma (HCC). Three-dimensional reconstruction techniques,including maximum intensity projection (MIP) and volume rendering (VR),with arterial phase images,were used to display the origination and course of both the intrahepatic and extrahepatic supplying arteries of HCC. The results were compared with the angiographic findings. Results Of 59 cases with massive type HCC,extrahepatic supplying arteries were found in 33. In 21 cases of diffuse type HCC four showed extrahepatic supplying arteries,and in nine cases of nodular type HCC only one had extra-hepatic supplying arteries. The HCC could get their extrahepatic blood supply via eight pathways. A total of 44 extrahepatic supplying arteries were detected,and 19 anomalously originated hepatic arteries were found. Conclusion The extrahepatic supplying arteries in hepatocellular carcinoma are common findings and their supplying pattern are extremely varied,which may be associated with the type and location of the tumors. Three-dimensional reconstruction technique with the help of triple-phase enhanced CT scanning on a 64-slice spiral CT scanner can provide excellent images as vivid and ideal as angiography can afford. Therefore,the times of angiography examination,the use of contrast media as well as the dose of radiation to both the patients and the physicians can be reduced as far as possible. The detailed information about extrahepatic blood supply is very useful for improving the therapeutic result of HCC.

Application of Exact Reconstruction Algorithm of Triple-source Helical CT in Dynamic Reconstruction / 航天医学与医学工程

Objective To reduce the artifacts produced by cardiac or respiratory motion,through the application of exact reconstruction algorithm with triple-source CT in dynamic reconstruction.Methods Simulation studies on two dynamic phantoms were performed with exact reconstruction algorithms of both single-source and triple-source spiral CT.The performance of triple-source spiral CT in dynamic reconstruction was evaluated with comparing the reconstruction results from triple-source and single-source configurations.Results The triple-source configuration could effectively reduce the artifact in dynamic reconstruction.Conclusion The results of this paper confirm the validity of the exact reconstruction algorithm of multi-source CT,which has the potential to improve the image quality in cardiac imaging and small animal imaging.

Clinical value of MSCT scanning and three-dimensional reconstructing well-liking shinbone prefabricating internal plate to repair catagmatic shinbone / 中国矫形外科杂志

[Objective]To explore a new technique of prefabricating internal plate.[Method]Three-dimensional reconstruction of the well-liking shinbone was performed by MSCT scanning and the length and shape of the catagmatic shinbone for operation was measured on well-liking shinbone.The shinbone curve was depicted using a self-designed skeletal curve-depicting.Then shape of the material for internal fixation was determined.[Result]The length and shape of the shinbone curve was accurately measured.The physiological curve of the shinbone was depicted.Then shape of the material for internal fixation was determined.[Conclusion]Three-dimensional well-liking shinbone reconstruction with MSCT and measurement facilitates the determination of the optimal length and shape of the internal fixation material to enhance the attachment between the material and the bone surface and consequently the therapeutic effects.One case's length and shape of internal fixation was dissatisfactory for hyperplasia of bone.But the length and shape of internal fixation has basal shape.

A Diagnostic Utility of Fitz-Hugh-Curtis Syndrome by Using Contrast Enhanced Abdominopelvic Computerized Tomo-graphy

PURPOSE: Fitz-Hugh-Curtis (FHC) syndrome is characterized by right upper quadrant pain due to perihepatitis with pelvic inflammatory disease (PID). It is diagnosed by using its typical symptoms, but final diagnosis is made by confirmation of the presence of laparoscopically visualized perihepatic violin string like adhesions. However, laparoscopy is difficult to perform in the emergency department. Recently, on computerized tomography (CT) a linear enhancement of the liver capsule was detected in a patient with FHC syndrome. We present a review of a series of 11 cases in female of FHC syndrome diagnosed by CT. METHODS: We reviewed the medical records and the CT findings of 11 cases of FHC syndrome diagnosed during 7 months in the emergency department. The clinico radiologic criteria of our hospital is as follows: First, right upper quadrant pain. Second, linear enhancement of the liver capsule in the contrast enhancement phase of CT. Third, no pathologic findings for the liver, the gallbladder and the biliary tract in CT. RESULTS: Eleven patients were diagnosed during 7 months by using criteria. The mean age was 30.2 (range: 16~46) years. Seven patients had a history of PID within 6 months. Seven of the 9 patients who take a pelvic examination were positive in C. trachomatis PCR (polymerase chain reaction), and another patient had a positive N. gonorrhoeae cervix culture. One patient who showed negative in both the C. trachomatis PCR and the N. gonorrhoeae cervix culture had cultured E. coli in urine and blood culture. CONCLUSION: CT makes easy the previously difficult diagnosis of FHC syndrome in female patients capable of pregnancy with right upper quadrant abdominal pain.

A Case of Pulmonary Artery Intimal Sarcoma Diagnosed with Multislice CT Scan with 3D Reconstruction

Pulmonary artery intimal sarcoma is a rare highly lethal disease, with additional retrograde extension to pulmonic valve and right ventricle being an extremely rare condition. It is frequently mistaken for pulmonary thromboembolism. We report a case of 64-year-old woman with progressive dyspnea initially suspected and treated for pulmonary thromboembolism. Her helical chest CT scan with 3 dimensional (3D) reconstruction combined with echocardiography revealed a compacting main pulmonary artery mass extending to the right ventricular outflow tract and the right pulmonary artery. After excision of the mass, the patient's condition improved dramatically, and the pathologic findings revealed pulmonary intimal sarcoma. This report emphasizes that helical chest CT with 3D reconstruction can be an important tool to differentiate the characteristics of pulmonary artery lesions, such as intimal sarcoma and thromboembolism.

Diagnostic value of helical CT in dissecting aneurysm of aorta / 医学研究生学报

Objective:To evaluate the diagnosis of dissecting aneurysm of aorta with helical CT. Methods:Enhanced helical CT scanning was performed on 12 patients with dissecting aneurysm of aorta. Results:On the axial images, the calcification ,the true and false channels and intimal flap、the location of the rupture and the aortic coverage were analysed. According to type of DeBakey, 3 cases were typeⅠ;2 were typeⅡ;7 were typeⅢ and According to type of A、B,10 cases were A;2 were B . Conclusion:Enhanced helical CT scan is the principal method in diagnosis of dissecting aneurysm of aorta. This examination which is very convenient、quick 、accurate and cheap has important significance in choosing therapeutic method and in evaluating therapeutic efficacy .

The Clinical Usefulness of SPIO-MRI in Detection and Staging of Hepatocellular Carcinoma / 대한간학회지

BACKGROUND/AIMS: It is still unclear whether Super Paramagnetic Iron Oxide-Magnetic Resonance Imaging (SPIO-MRI) is a clinically useful imaging modality for patients with hepatocellular carcinoma (HCC). This study searched for the clinical usefulness and limitations of SPIO-MRI with respect to tumor detection capacity, false positive and negative rate, and early recurrence rate. METHODS: From December 1999 to February 2001, 218 patients who were surgical candidates by 3-phase dynamic helical CT (3dHCT) were enrolled. We reviewed the medical records and radiologic findings, retrospectively, and postulated the post-operative pathologic findings and the early recurrences within 3 months as the standards for the true positive lesion. RESULTS: The mean number of nodules detected by SPIO-MRI was significantly more numerous than that of 3dHCT (p<0.01). Modifications of treatment strategy due to the discordant findings between SPIO-MRI and 3dHCT for tumor resectability were observed in 22 (10.1%) out of 218 patients. Early recurrences were observed in 10 patients (7.8%). The false positive and negative rates of SPIO-MRI were 6.3% and 13.3%, respectively. CONCLUSIONS: We demonstrated that the tumor detection rate of SPIO-MRI was better than that of 3dHCT. Given the relatively acceptable false positive and negative rates, SPIO-MRI could be an appropriate preoperative imaging modality for patients with HCCs.

Application on Post-processing Technique of 16-slice Helical CT Scanning for Cervical Spinal Cord Lesion / 医疗卫生装备

Objective To discuss the application values of image reconstructive technique in 16-slice helical CT scanning. Methods 32 cervical spinal cord lesion images which have processed in MPR, MIP and VR were reviewed to discover the best image reconstructive form. Results By grading, reconstruction score of MPR, MIP and VR was 4.75, 1.75 and 4.5, MPR and VR in top. Conclusion 16-slice CT scanning with MPR and VR image reconstructive of cervical spinal cord can be satisfied the clinical demands.

Study on Imaging Quality of 64-Slice Spiral CT Long Coverage Angiography in Intracranial and Cervical Arteries / 医疗卫生装备

Objective To study the value of 64-Slice Spiral CT angiography with I.V.Blous contrast medium in in- tracranial and cervical arteries. Methods 100 cases were examined with I.V.Blous of contrast medium in intracranial and cervical arteries CTA while 100 cases were not examined with I.V.Blous. The images between I.V.Blous group and contrast group were analyzed retrospectively and comparatively. Results The rate of CTA success and the image quality of I.V.Blous group were significantly higher and better than those of contrast group. There was statistically significant difference(P

Clinical Application of Lung Lesion Pathological Biopsy by CT-guided Fine Needle Aspiration / 医疗卫生装备

Objective To study the clinical application of the lung lesion biopsy through helical CT-guided fine needle aspiration. Methods 44 cases of lung lesions were pathologically biopsy diagnosed through helical CT-guided fine needle aspiration. Results All 44 lung lesions were successfully conducted biopsy through CT-guided fine needle aspiration, and the pathological confirmed diagnosis rate was 98%. Conclusion With high diagnosis rate, CT- fine needle aspiration is clinically applicable and the complication is rare. It is easily-operated, safe and economical.