AIM: The purpose of this study was to compare the diagnostic accuracy of biphasic multi-detector row helical computed tomography (MDCT), digital subtraction angiography (DSA)and Lipiodol computed tomography (CT) in de...AIM: The purpose of this study was to compare the diagnostic accuracy of biphasic multi-detector row helical computed tomography (MDCT), digital subtraction angiography (DSA)and Lipiodol computed tomography (CT) in detection of hypervascular hepatocellular carcinoma (HCC).METHODS: Twenty-eight patients with nodular HCC underwent biphasic MDCT examination: hepatic arterial phase (HAP) 25 s and portal venous phase (PVP) 70 s after injection of the contrast medium (1.5 mL/kg). They also underwent hepatic angiography and intra-arterial infusion of iodized oil. Lipiodol CT was performed 3-4 wk after infusion. MDCT images were compared with DSA and Lipiodol CT images for detection of hepatic nodules.RESULTS: The three imaging techniques had the same sensitivity in detecting nodules ＞20 mm in diameter. There was no significant difference in the sensitivity among HAP-MDCT, Lipiodol CT and DSA for nodules of 10-20 mm in diameter. For the nodules ＜10 mm in diameter, HAP-MDCT identified 47, Lipiodol CT detected 27 (X2= 11.3, P= 0.005＜0.01, HAP-MDCT vs Lipiodol CT) and DSA detected 16(X2= 9.09, P= 0.005＜0.01 vs Lipiodol CT and X2= 29.03,P = 0.005＜0.01 vs HAP-MDCT). However, six nodules ＜10 mm in diameter were detected only by Lipiodol CT.CONCLUSION: MDCT and Lipiodol CT are two complementary modalities. At present, MDCT does not obviate the need for DSA and subsequent Lipiodol CT as a preoperative examination for HCC.展开更多
Objective To determine if multi-detector CT （MDCT） characterization of plaque is correlated with the classification of acute coronary syndrome （ACS）. Methods Altogether 1900 patients were examined by MDCT from De...Objective To determine if multi-detector CT （MDCT） characterization of plaque is correlated with the classification of acute coronary syndrome （ACS）. Methods Altogether 1900 patients were examined by MDCT from December 2007 to May 2009, of whom 95 patients fulfilled the criteria of ACS. Those patients were divided into the discrete plaque group （n=61） and diffuse plaque group （n=34） based on the findings in MDCT. The clinical diagnosis of ACS and CT results were analyzed, including segment stenosis score, segment involvement score, 3-vessel plaque score, left main score, calcification score, and remodeling index. The incidences of major adverse cardiac events in follow-up period were also recorded. Results The patients of the diffuse plaque group were older than those of the discrete plaque group （P〈0.0001）. The diffuse plaque group presented more cases of hypertension, peripheral artery disease, diabetes, and heart failure than discrete plaque group （all P〈0.05）. All the 5 patients with ST-segment elevation myocardial infarction were found in discrete plaque group. The segment stenosis score of the discrete plaque group was lower than that of the diffuse plaque group （5.15±3.55 vs. 14.91±5.37, P〈0.001）. The other four scores demonstrated signiflcant inter-group difference as well （all P〈0.05）. The remodeling index of the discrete plaque group was higher （1. 12±0.16 vs. 0.97±0.20, P〈0.05）. Follow-up data showed that major adverse cardiac events occurred more frequently in diffuse plaque group than in discrete group （29.41% vs. 11.48%, P=0.0288）. Conclusions Characteristics of discrete and diffuse plaques may be significantly different among different classes of ACS. The diffuse plaque may present higher risk, correlated to higher mortality. The diagnosis of discrete and diffuse plaques by MDCT would provide a new insight into the prognosis and treatment of ACS.展开更多
Acute intestinal ischemia is an abdominal emergency occurring in nearly 1% of patients presenting with acute abdomen. The causes can be occlusive or non occlusive. Early diagnosis is important to improve survival rate...Acute intestinal ischemia is an abdominal emergency occurring in nearly 1% of patients presenting with acute abdomen. The causes can be occlusive or non occlusive. Early diagnosis is important to improve survival rates. In most cases of late or missed diagnosis, the mortality rate from intestinal infarction is very high, with a reported value ranging from 60% to 90%. Multidetector computed tomography(MDCT) is a fundamental imaging technique that must be promptly performed in all patients with suspected bowel ischemia. Thanks to the new dedicated reconstruction program, its diagnostic potential is much improved compared to the past and currently it is superior to that of any other noninvasive technique. The increased spatial and temporal resolution, high-quality multi-planar reconstructions, maximum intensity projections, vessel probe, surface-shaded volume rending and tissue transition projections make MDCT the gold standard for the diagnosis of intestinal ischemia, with reported sensitivity, specificity, positive and negative predictive values of 64%-93%, 92%-100%, 90%-100% and 94%-98%, respectively. MDCT contributes to appropriate treatment planning and provides important prognostic informationthanks to its ability to define the nature and extent of the disease. The purpose of this review is to examine the diagnostic and prognostic role of MDCT in bowel ischemia with special regard to the state of art new reconstruction software.展开更多
Over the past several years,advances in the technical domain of computed tomography(CT) have influenced the trend of imaging modalities used in the clinical evaluation of the urinary system.Renal collecting systems ca...Over the past several years,advances in the technical domain of computed tomography(CT) have influenced the trend of imaging modalities used in the clinical evaluation of the urinary system.Renal collecting systems can be illustrated more precisely with the advent of multi-detector row CT through thinner slices,high speed acquisitions,and enhanced longitudinal spatial resolution resulting in improved reformatted coronal images.On the other hand,a significant increase in exposure to ionizing radiation,especially in the radiosensitive organs,such as the gonads,is a concern with the increased utilization of urinary tract CT.In this article,we discuss the strategies and techniques availablefor reducing radiation dose for a variety of urinary tractCT protocols with metabolic clinical examples.We also reviewed CT for hematuria evaluation and related scan parameter optimization such as,reducing the number of acquisition phases,CT angiography of renal donors and lowering tube potential,when possible.展开更多
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...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.展开更多
Pancreatic vipoma is an extremely rare tumor accounting for less than 2% of endocrine pancreatic neoplasms with a reported incidence of 0.1-0.6 per million. While cross-sectional imaging findings are usually not speci...Pancreatic vipoma is an extremely rare tumor accounting for less than 2% of endocrine pancreatic neoplasms with a reported incidence of 0.1-0.6 per million. While cross-sectional imaging findings are usually not specific, exact localization of the tumor by means of either computed tomography(CT) or magnetic resonance(MR) is pivotal for surgical planning. However, cross-sectional imaging findings are usually not specific and further characterization of the tumor may only be achieved bysomatostatin-receptor scintigraphy(SRS). We report the case of a 70 years old female with a two years history of watery diarrhoea who was found to have a solid, inhomogeneously enhancing lesion at the level of the pancreatic tail at Gadolinium-enhanced MR(Somatom Trio 3T, Siemens, Germany). The tumor had been prospectively overlooked at a contrast-enhanced multi-detector CT(Aquilion 64, Toshiba, Japan) performed after i.v. bolus injection of only 100 cc of iodinated non ionic contrast media because of a chronic renal failure(3.4 mg/mL) but it was subsequently confirmed by SRS. The patient first underwent a successful symptomatic treatment with somatostatin analogues and was then submitted to a distal pancreasectomy with splenectomy to remove a capsulated whitish tumor which turned out to be a well-differentiated vipoma at histological and immuno-histochemical analysis.展开更多
AIM: To assess the feasibility and usefulness of multi-detector CT enterography with orally administered iso-osmotic mannitol as negative contrast in demonstrating small bowel disease.METHODS: Thirteen volunteers and ...AIM: To assess the feasibility and usefulness of multi-detector CT enterography with orally administered iso-osmotic mannitol as negative contrast in demonstrating small bowel disease.METHODS: Thirteen volunteers and 38 patients with various kinds of small bowel disease were examined. We administered about 1 500 mL iso-osmotic mannitol as negative contrast agent and then proceeded with helical CT scanning on a Siemens Sensation 16 scanner. All volunteers and patients were interviewed about their tolerance of the procedure. Two radiologists postprocessed imaging data with MPR, thin MIP, VRT and INSPACE when necessary and then interpreted the scans,and adequacy of luminal distention was evaluated on a four-point scale. Demonstration of features of various kinds of small bowel disease was analyzed.RESULTS: The taste of iso-osmotic mannitol is good (slightly sweet) and acceptable by all. Small bowel distention was excellent and moderate in most volunteers and patients. CT features of many kinds of diseases such as tumors, Crohn's disease,and small bowel obstruction,etc. were clearly displayed.CONCLUSION: Multi-detector CT enterography with iso-osmotic mannitol as negative contrast to distend the small bowel is a simple, rapid, noninvasive and effective method of evaluating small bowel disease.展开更多
Objective To study pelvicaliceal anatomy using three-dimensional images derived by 16-slice multi-detector CT urography （CTU）,and to discuss the role of CTU in planning for an optimal percutaneous approach into the ...Objective To study pelvicaliceal anatomy using three-dimensional images derived by 16-slice multi-detector CT urography （CTU）,and to discuss the role of CTU in planning for an optimal percutaneous approach into the pelvicaliceal system （PCS） prior to minimally invasive percutaneous nephrolithotomy （MPCNL）.Methods Fifteen patients with complex renal calculi were collected from September 2004 to March 2005 in order to choose an optimal percutaneous approach into the PCS prior to MPCNL,展开更多
基金Supported by the Medical Science Research Fund of Sichuan Province,No. 200054
文摘AIM: The purpose of this study was to compare the diagnostic accuracy of biphasic multi-detector row helical computed tomography (MDCT), digital subtraction angiography (DSA)and Lipiodol computed tomography (CT) in detection of hypervascular hepatocellular carcinoma (HCC).METHODS: Twenty-eight patients with nodular HCC underwent biphasic MDCT examination: hepatic arterial phase (HAP) 25 s and portal venous phase (PVP) 70 s after injection of the contrast medium (1.5 mL/kg). They also underwent hepatic angiography and intra-arterial infusion of iodized oil. Lipiodol CT was performed 3-4 wk after infusion. MDCT images were compared with DSA and Lipiodol CT images for detection of hepatic nodules.RESULTS: The three imaging techniques had the same sensitivity in detecting nodules ＞20 mm in diameter. There was no significant difference in the sensitivity among HAP-MDCT, Lipiodol CT and DSA for nodules of 10-20 mm in diameter. For the nodules ＜10 mm in diameter, HAP-MDCT identified 47, Lipiodol CT detected 27 (X2= 11.3, P= 0.005＜0.01, HAP-MDCT vs Lipiodol CT) and DSA detected 16(X2= 9.09, P= 0.005＜0.01 vs Lipiodol CT and X2= 29.03,P = 0.005＜0.01 vs HAP-MDCT). However, six nodules ＜10 mm in diameter were detected only by Lipiodol CT.CONCLUSION: MDCT and Lipiodol CT are two complementary modalities. At present, MDCT does not obviate the need for DSA and subsequent Lipiodol CT as a preoperative examination for HCC.
基金Supported by the Supporting Program of the "Eleventh Five-year Plan" for Science & Technology Research of China (2006BAI01A02)
文摘Objective To determine if multi-detector CT （MDCT） characterization of plaque is correlated with the classification of acute coronary syndrome （ACS）. Methods Altogether 1900 patients were examined by MDCT from December 2007 to May 2009, of whom 95 patients fulfilled the criteria of ACS. Those patients were divided into the discrete plaque group （n=61） and diffuse plaque group （n=34） based on the findings in MDCT. The clinical diagnosis of ACS and CT results were analyzed, including segment stenosis score, segment involvement score, 3-vessel plaque score, left main score, calcification score, and remodeling index. The incidences of major adverse cardiac events in follow-up period were also recorded. Results The patients of the diffuse plaque group were older than those of the discrete plaque group （P〈0.0001）. The diffuse plaque group presented more cases of hypertension, peripheral artery disease, diabetes, and heart failure than discrete plaque group （all P〈0.05）. All the 5 patients with ST-segment elevation myocardial infarction were found in discrete plaque group. The segment stenosis score of the discrete plaque group was lower than that of the diffuse plaque group （5.15±3.55 vs. 14.91±5.37, P〈0.001）. The other four scores demonstrated signiflcant inter-group difference as well （all P〈0.05）. The remodeling index of the discrete plaque group was higher （1. 12±0.16 vs. 0.97±0.20, P〈0.05）. Follow-up data showed that major adverse cardiac events occurred more frequently in diffuse plaque group than in discrete group （29.41% vs. 11.48%, P=0.0288）. Conclusions Characteristics of discrete and diffuse plaques may be significantly different among different classes of ACS. The diffuse plaque may present higher risk, correlated to higher mortality. The diagnosis of discrete and diffuse plaques by MDCT would provide a new insight into the prognosis and treatment of ACS.
文摘Acute intestinal ischemia is an abdominal emergency occurring in nearly 1% of patients presenting with acute abdomen. The causes can be occlusive or non occlusive. Early diagnosis is important to improve survival rates. In most cases of late or missed diagnosis, the mortality rate from intestinal infarction is very high, with a reported value ranging from 60% to 90%. Multidetector computed tomography(MDCT) is a fundamental imaging technique that must be promptly performed in all patients with suspected bowel ischemia. Thanks to the new dedicated reconstruction program, its diagnostic potential is much improved compared to the past and currently it is superior to that of any other noninvasive technique. The increased spatial and temporal resolution, high-quality multi-planar reconstructions, maximum intensity projections, vessel probe, surface-shaded volume rending and tissue transition projections make MDCT the gold standard for the diagnosis of intestinal ischemia, with reported sensitivity, specificity, positive and negative predictive values of 64%-93%, 92%-100%, 90%-100% and 94%-98%, respectively. MDCT contributes to appropriate treatment planning and provides important prognostic informationthanks to its ability to define the nature and extent of the disease. The purpose of this review is to examine the diagnostic and prognostic role of MDCT in bowel ischemia with special regard to the state of art new reconstruction software.
文摘Over the past several years,advances in the technical domain of computed tomography(CT) have influenced the trend of imaging modalities used in the clinical evaluation of the urinary system.Renal collecting systems can be illustrated more precisely with the advent of multi-detector row CT through thinner slices,high speed acquisitions,and enhanced longitudinal spatial resolution resulting in improved reformatted coronal images.On the other hand,a significant increase in exposure to ionizing radiation,especially in the radiosensitive organs,such as the gonads,is a concern with the increased utilization of urinary tract CT.In this article,we discuss the strategies and techniques availablefor reducing radiation dose for a variety of urinary tractCT protocols with metabolic clinical examples.We also reviewed CT for hematuria evaluation and related scan parameter optimization such as,reducing the number of acquisition phases,CT angiography of renal donors and lowering tube potential,when possible.
文摘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.
文摘Pancreatic vipoma is an extremely rare tumor accounting for less than 2% of endocrine pancreatic neoplasms with a reported incidence of 0.1-0.6 per million. While cross-sectional imaging findings are usually not specific, exact localization of the tumor by means of either computed tomography(CT) or magnetic resonance(MR) is pivotal for surgical planning. However, cross-sectional imaging findings are usually not specific and further characterization of the tumor may only be achieved bysomatostatin-receptor scintigraphy(SRS). We report the case of a 70 years old female with a two years history of watery diarrhoea who was found to have a solid, inhomogeneously enhancing lesion at the level of the pancreatic tail at Gadolinium-enhanced MR(Somatom Trio 3T, Siemens, Germany). The tumor had been prospectively overlooked at a contrast-enhanced multi-detector CT(Aquilion 64, Toshiba, Japan) performed after i.v. bolus injection of only 100 cc of iodinated non ionic contrast media because of a chronic renal failure(3.4 mg/mL) but it was subsequently confirmed by SRS. The patient first underwent a successful symptomatic treatment with somatostatin analogues and was then submitted to a distal pancreasectomy with splenectomy to remove a capsulated whitish tumor which turned out to be a well-differentiated vipoma at histological and immuno-histochemical analysis.
文摘AIM: To assess the feasibility and usefulness of multi-detector CT enterography with orally administered iso-osmotic mannitol as negative contrast in demonstrating small bowel disease.METHODS: Thirteen volunteers and 38 patients with various kinds of small bowel disease were examined. We administered about 1 500 mL iso-osmotic mannitol as negative contrast agent and then proceeded with helical CT scanning on a Siemens Sensation 16 scanner. All volunteers and patients were interviewed about their tolerance of the procedure. Two radiologists postprocessed imaging data with MPR, thin MIP, VRT and INSPACE when necessary and then interpreted the scans,and adequacy of luminal distention was evaluated on a four-point scale. Demonstration of features of various kinds of small bowel disease was analyzed.RESULTS: The taste of iso-osmotic mannitol is good (slightly sweet) and acceptable by all. Small bowel distention was excellent and moderate in most volunteers and patients. CT features of many kinds of diseases such as tumors, Crohn's disease,and small bowel obstruction,etc. were clearly displayed.CONCLUSION: Multi-detector CT enterography with iso-osmotic mannitol as negative contrast to distend the small bowel is a simple, rapid, noninvasive and effective method of evaluating small bowel disease.
文摘Objective To study pelvicaliceal anatomy using three-dimensional images derived by 16-slice multi-detector CT urography （CTU）,and to discuss the role of CTU in planning for an optimal percutaneous approach into the pelvicaliceal system （PCS） prior to minimally invasive percutaneous nephrolithotomy （MPCNL）.Methods Fifteen patients with complex renal calculi were collected from September 2004 to March 2005 in order to choose an optimal percutaneous approach into the PCS prior to MPCNL,
