Significant advances in imaging technology have changed the management of pancreatic cancer. In computed tomography (CT), this has included development of multidetector row, rapid, thin-section imaging that has also f...Significant advances in imaging technology have changed the management of pancreatic cancer. In computed tomography (CT), this has included development of multidetector row, rapid, thin-section imaging that has also facilitated the advent of advanced reconstructions, which in turn has offered new perspectives from which to evaluate this disease. In magnetic resonance imaging, advances including higher field strengths, thin-section volumetric acquisitions, diffusion weighted imaging, and liver specific contrast agents have also resulted in new tools for diagnosis and staging. Endoscopic ultrasound has resulted in the ability to provide high-resolution imaging rivaling intraoperative ultrasound, along with the ability to biopsy via real time imaging suspected pancreatic lesions. Positron emission tomography with CT, while still evolving in its role, provides whole body staging as well as the unique imaging characteristic of metabolic activity to aid disease management. This article will review these modalities in the diagnosis and staging of pancreatic cancer.展开更多
Critical coronary stenosis have been shown to contribute to only a minority of acute coronary syndromes and sudden cardiac death.Autopsy studies have identified a subgroup of high-risk patients with disrupted vulnerab...Critical coronary stenosis have been shown to contribute to only a minority of acute coronary syndromes and sudden cardiac death.Autopsy studies have identified a subgroup of high-risk patients with disrupted vulnerable plaque and modest stenosis.Consequently,a clinical need exists to develop methods to identify these plaques prospectively before disruption and clinical expression of disease.Recent advances in invasive and non-invasive imaging techniques have shown the potential to identify these high-risk plaques.Non-invasive imaging with magnetic resonance imaging,computed tomography and positron emission tomography holds the potential to differentiate between low-and highrisk plaques.There have been significant technological advances in non-invasive imaging modalities,and the aim is to achieve a diagnostic sensitivity for these technologies similar to that of the invasive modalities.Molecular imaging with the use of novel targeted nanoparticles may help in detecting high-risk plaques that will ultimately cause acute myocardial infarction.Moreover,nanoparticle-based imaging may even provide non-invasive treatments for these plaques.However,at present none of these imaging modalities are able to detect vulnerable plaque nor have they been shown to definitively predict outcome.Further trials are needed to provide more information regarding the natural history of high-risk but non-flow-limiting plaque to establish patient specific targeted therapy and to refine plaque stabilizing strategies in the future.展开更多
We present a case of the right aortic arch with kommerell diverticulum (KD) and aberrant left subclavian artery in a symptomatic 50-year-old patient with a calcification in the presumed attachment site of the ligament...We present a case of the right aortic arch with kommerell diverticulum (KD) and aberrant left subclavian artery in a symptomatic 50-year-old patient with a calcification in the presumed attachment site of the ligamentum arteriosum (LA) to the KD. In another 30-year-old male patient, the entire course of a calcified LA was demonstrated using multidetector row computed tomography.展开更多
AIM: To assess and compare the image quality of 4% sorbitol and diluted iodine 2%(positive oral contrast agent) in abdomino-pelvic multi-detector computed tomography.METHODS: Two-hundred patients, referred to the Radi...AIM: To assess and compare the image quality of 4% sorbitol and diluted iodine 2%(positive oral contrast agent) in abdomino-pelvic multi-detector computed tomography.METHODS: Two-hundred patients, referred to the Radiology Department of a central educational hospital for multi-detector row abdominal-pelvic computed tomography, were randomly divided into two groups: the first group received 1500 m L of 4% sorbitol solution as a neutral contrast agent, while in the second group 1500 m L of meglumin solution as a positive contrast agent was administered in a one-way randomized prospective study. The results were independently reviewed by two radiologists. Luminal distension and mural thickness and mucosal enhancement were compared between the two groups. Statistical analysis of the results was performed by Statistical Package for the Social Sciences software version 16 and the Mann-Whitney test at a confidence level of 95%. RESULTS: Use of neutral oral contrast agent significantly improved visualization of the small bowel wall thickness and mural appearance in comparison with administration of positive contrast agent(P < 0.01). In patients who received sorbitol, the small bowel showed better distention compared with those who received iodine solution as a positive contrast agent(P < 0.05). CONCLUSION: The results of the study demonstrated that oral administration of sorbitol solution allows better luminal distention and visualization of mural features than iodine solution as a positive contrast agent.展开更多
Background： Retroperitoneal fibrosis （RPF） and lymphoma presenting as retroperitoneal mass may closely resemble each other and misdiagnosis may occur. This study investigated the differential imaging features of RP...Background： Retroperitoneal fibrosis （RPF） and lymphoma presenting as retroperitoneal mass may closely resemble each other and misdiagnosis may occur. This study investigated the differential imaging features of RPF and lymphoma which presented as a retroperitoneal soft tissue using multidetector-row computed tomography （MDCT）. Methods： The 42 consecutive patients were included in this retrospective review, including 19 RPF patients （45.2%; including 13 males and 6 females; mean age： 56.7 ± 6.2 years） and 23 patients with lymphoma （54.8%： including 14 males and 9 females： mean age： 57.4 ± 12.3 years）. An array of qualitative computed tomography （CT） features of lesions in 42 consecutive patients with newly diagnosed untreated RPF and lymphoma were retrospectively analyzed. The quantitative size of the lesion at the para-aortic region and attenuation in the precontrast, arterial, and portal phases were calculated in regions of interest and compared between the patients with newly diagnosed untreated RPF and with lymphoma. Receiver operating characteristic curve analysis was used to assess the potential diagnostic value of each quantitative parameter. Inter-reader concordance was also calculated. Results： Mean ages between patients with RPF and lymphoma were not significantly different （56.7 ±6.2 years vs. 57.4 ± 12.3 years P = 0.595）. Compared to those in patients with lymphoma, homogeneous enhancement （65.2% vs. 94.7%, P = 0.027） and pelvic extension （52.2% vs. 89.5%, P= 0.017） were significantly more common while the involvement of additional nodes （78.3% vs. 5.3%, P 〈 0.001）, suprarenal extension （60.9% vs. 15.8%, P = 0.004）, and aortic displacement （43.5% vs. 5.3%, P 0.006） were significantly less common in patients with RPF. Lesion size at the para-aorta was significantly greater in patients with lymphoma, compared with RPF patients （3.9 ± 1.2 cm vs. 1.8 ± 0.6 cm; P 〈 0.001 ）. The attenuation values in three phases were not significantly 展开更多
AIM:To distinguish acinar cell carcinoma(ACC)from pancreatic adenocarcinoma(AC)by comparing their computed tomography findings.METHODS:Patients with ACC and AC were identified on the basis of results obtained using su...AIM:To distinguish acinar cell carcinoma(ACC)from pancreatic adenocarcinoma(AC)by comparing their computed tomography findings.METHODS:Patients with ACC and AC were identified on the basis of results obtained using surgically resected pancreatectomy specimens.The preoperative computer tomographic images of 6 acinar cell carcinoma patients and 67 pancreatic adenocarcinoma patients in 4 phases(non-contrast,arterial,portal venous,and delayed phase)were compared.The scan delay times were 40,70,and 120 s for each contrast-enhanced phase.The visual pattern,tomographic attenuation value,and time attenuation curve were assessed and compared between AC and ACC cases using the 2test,Wilcoxon signed-rank test,and Mann Whitney U test.RESULTS:The adenocarcinomas tended to be hypodense in all 4 phases.The acinar cell carcinomas also tended to be hypodense in the 3 contrast-enhancedphases,although their computed tomographic attenuation values were higher.Further,5 of the 6 acinar cell carcinomas(83%)were isodense in the non-contrast phase.The time attenuation curve of the adenocarcinomas showed a gradual increase through the 4 phases,and all adenocarcinomas showed peak enhancement during the delayed phase.The time attenuation curve of the acinar cell carcinomas showed peak enhancement during the portal venous phase in 4 cases and during the arterial phase in 2 cases.None of the 6 acinar cell carcinomas showed peak enhancement during the delayed phase.CONCLUSION:The tumor density in the non-contrast phase and time attenuation curve pattern clearly differ between acinar cell carcinomas and adenocarcinomas,and multidetector-row computed tomography can thus distinguish these tumors.展开更多
Phytobezoar is the most common type of bezoar.It is composed of indigestible vegetable matter and is usually found in the stomach.Biliary phytobezoar is extremely rare and difficult to diagnose preoperatively.The path...Phytobezoar is the most common type of bezoar.It is composed of indigestible vegetable matter and is usually found in the stomach.Biliary phytobezoar is extremely rare and difficult to diagnose preoperatively.The pathogenesis is not clear,and there have been only a few reports of biliary bezoars associated with sphincteric impairmentat the ampulla of Vater.Here,we present a report of biliary bezoar that resulted in jejunal obstruction.We were unable to identifythe bezoar in the extrahepatic bile duct until it obstructed the small bowel lumen.To our knowledge,this is the first report of small bowel obstruction resulting frommigration of a biliary bezoar.展开更多
Multidetector-row computed tomography(MDCT) has become one of the major tools in diagnosing and evaluating patients with coronary artery disease in recent years.In selected patients,MDCT has been shown to provide more...Multidetector-row computed tomography(MDCT) has become one of the major tools in diagnosing and evaluating patients with coronary artery disease in recent years.In selected patients,MDCT has been shown to provide more reliable accuracy in detection of stent patency than invasive coronary angiography.Chiou et al reported a delicate infarcted myocardium at-risk score.According to their results,the MDCT-based myocardium at-risk score had a good correlation with the thallium 201 ST-segment elevation myocardial infarction-based summed difference score(r = 0.841,P < 0.001).They claimed that dual-phase MDCT is useful in detecting different patterns of obstructive lesions and the extent of myocardium at risk.In this commentary,we discuss the current status of the clinical application of MDCT in patients with myocardial infarction in relation to evaluating the myocardial perfusion defect,detecting reversible myocardial ischemia,assessing myocardial viability,estimating target lesion restenosis,and calculating of fractional flow reserve from MDCT.展开更多
文摘Significant advances in imaging technology have changed the management of pancreatic cancer. In computed tomography (CT), this has included development of multidetector row, rapid, thin-section imaging that has also facilitated the advent of advanced reconstructions, which in turn has offered new perspectives from which to evaluate this disease. In magnetic resonance imaging, advances including higher field strengths, thin-section volumetric acquisitions, diffusion weighted imaging, and liver specific contrast agents have also resulted in new tools for diagnosis and staging. Endoscopic ultrasound has resulted in the ability to provide high-resolution imaging rivaling intraoperative ultrasound, along with the ability to biopsy via real time imaging suspected pancreatic lesions. Positron emission tomography with CT, while still evolving in its role, provides whole body staging as well as the unique imaging characteristic of metabolic activity to aid disease management. This article will review these modalities in the diagnosis and staging of pancreatic cancer.
文摘Critical coronary stenosis have been shown to contribute to only a minority of acute coronary syndromes and sudden cardiac death.Autopsy studies have identified a subgroup of high-risk patients with disrupted vulnerable plaque and modest stenosis.Consequently,a clinical need exists to develop methods to identify these plaques prospectively before disruption and clinical expression of disease.Recent advances in invasive and non-invasive imaging techniques have shown the potential to identify these high-risk plaques.Non-invasive imaging with magnetic resonance imaging,computed tomography and positron emission tomography holds the potential to differentiate between low-and highrisk plaques.There have been significant technological advances in non-invasive imaging modalities,and the aim is to achieve a diagnostic sensitivity for these technologies similar to that of the invasive modalities.Molecular imaging with the use of novel targeted nanoparticles may help in detecting high-risk plaques that will ultimately cause acute myocardial infarction.Moreover,nanoparticle-based imaging may even provide non-invasive treatments for these plaques.However,at present none of these imaging modalities are able to detect vulnerable plaque nor have they been shown to definitively predict outcome.Further trials are needed to provide more information regarding the natural history of high-risk but non-flow-limiting plaque to establish patient specific targeted therapy and to refine plaque stabilizing strategies in the future.
文摘We present a case of the right aortic arch with kommerell diverticulum (KD) and aberrant left subclavian artery in a symptomatic 50-year-old patient with a calcification in the presumed attachment site of the ligamentum arteriosum (LA) to the KD. In another 30-year-old male patient, the entire course of a calcified LA was demonstrated using multidetector row computed tomography.
文摘AIM: To assess and compare the image quality of 4% sorbitol and diluted iodine 2%(positive oral contrast agent) in abdomino-pelvic multi-detector computed tomography.METHODS: Two-hundred patients, referred to the Radiology Department of a central educational hospital for multi-detector row abdominal-pelvic computed tomography, were randomly divided into two groups: the first group received 1500 m L of 4% sorbitol solution as a neutral contrast agent, while in the second group 1500 m L of meglumin solution as a positive contrast agent was administered in a one-way randomized prospective study. The results were independently reviewed by two radiologists. Luminal distension and mural thickness and mucosal enhancement were compared between the two groups. Statistical analysis of the results was performed by Statistical Package for the Social Sciences software version 16 and the Mann-Whitney test at a confidence level of 95%. RESULTS: Use of neutral oral contrast agent significantly improved visualization of the small bowel wall thickness and mural appearance in comparison with administration of positive contrast agent(P < 0.01). In patients who received sorbitol, the small bowel showed better distention compared with those who received iodine solution as a positive contrast agent(P < 0.05). CONCLUSION: The results of the study demonstrated that oral administration of sorbitol solution allows better luminal distention and visualization of mural features than iodine solution as a positive contrast agent.
文摘Background： Retroperitoneal fibrosis （RPF） and lymphoma presenting as retroperitoneal mass may closely resemble each other and misdiagnosis may occur. This study investigated the differential imaging features of RPF and lymphoma which presented as a retroperitoneal soft tissue using multidetector-row computed tomography （MDCT）. Methods： The 42 consecutive patients were included in this retrospective review, including 19 RPF patients （45.2%; including 13 males and 6 females; mean age： 56.7 ± 6.2 years） and 23 patients with lymphoma （54.8%： including 14 males and 9 females： mean age： 57.4 ± 12.3 years）. An array of qualitative computed tomography （CT） features of lesions in 42 consecutive patients with newly diagnosed untreated RPF and lymphoma were retrospectively analyzed. The quantitative size of the lesion at the para-aortic region and attenuation in the precontrast, arterial, and portal phases were calculated in regions of interest and compared between the patients with newly diagnosed untreated RPF and with lymphoma. Receiver operating characteristic curve analysis was used to assess the potential diagnostic value of each quantitative parameter. Inter-reader concordance was also calculated. Results： Mean ages between patients with RPF and lymphoma were not significantly different （56.7 ±6.2 years vs. 57.4 ± 12.3 years P = 0.595）. Compared to those in patients with lymphoma, homogeneous enhancement （65.2% vs. 94.7%, P = 0.027） and pelvic extension （52.2% vs. 89.5%, P= 0.017） were significantly more common while the involvement of additional nodes （78.3% vs. 5.3%, P 〈 0.001）, suprarenal extension （60.9% vs. 15.8%, P = 0.004）, and aortic displacement （43.5% vs. 5.3%, P 0.006） were significantly less common in patients with RPF. Lesion size at the para-aorta was significantly greater in patients with lymphoma, compared with RPF patients （3.9 ± 1.2 cm vs. 1.8 ± 0.6 cm; P 〈 0.001 ）. The attenuation values in three phases were not significantly
文摘AIM:To distinguish acinar cell carcinoma(ACC)from pancreatic adenocarcinoma(AC)by comparing their computed tomography findings.METHODS:Patients with ACC and AC were identified on the basis of results obtained using surgically resected pancreatectomy specimens.The preoperative computer tomographic images of 6 acinar cell carcinoma patients and 67 pancreatic adenocarcinoma patients in 4 phases(non-contrast,arterial,portal venous,and delayed phase)were compared.The scan delay times were 40,70,and 120 s for each contrast-enhanced phase.The visual pattern,tomographic attenuation value,and time attenuation curve were assessed and compared between AC and ACC cases using the 2test,Wilcoxon signed-rank test,and Mann Whitney U test.RESULTS:The adenocarcinomas tended to be hypodense in all 4 phases.The acinar cell carcinomas also tended to be hypodense in the 3 contrast-enhancedphases,although their computed tomographic attenuation values were higher.Further,5 of the 6 acinar cell carcinomas(83%)were isodense in the non-contrast phase.The time attenuation curve of the adenocarcinomas showed a gradual increase through the 4 phases,and all adenocarcinomas showed peak enhancement during the delayed phase.The time attenuation curve of the acinar cell carcinomas showed peak enhancement during the portal venous phase in 4 cases and during the arterial phase in 2 cases.None of the 6 acinar cell carcinomas showed peak enhancement during the delayed phase.CONCLUSION:The tumor density in the non-contrast phase and time attenuation curve pattern clearly differ between acinar cell carcinomas and adenocarcinomas,and multidetector-row computed tomography can thus distinguish these tumors.
文摘Phytobezoar is the most common type of bezoar.It is composed of indigestible vegetable matter and is usually found in the stomach.Biliary phytobezoar is extremely rare and difficult to diagnose preoperatively.The pathogenesis is not clear,and there have been only a few reports of biliary bezoars associated with sphincteric impairmentat the ampulla of Vater.Here,we present a report of biliary bezoar that resulted in jejunal obstruction.We were unable to identifythe bezoar in the extrahepatic bile duct until it obstructed the small bowel lumen.To our knowledge,this is the first report of small bowel obstruction resulting frommigration of a biliary bezoar.
文摘Multidetector-row computed tomography(MDCT) has become one of the major tools in diagnosing and evaluating patients with coronary artery disease in recent years.In selected patients,MDCT has been shown to provide more reliable accuracy in detection of stent patency than invasive coronary angiography.Chiou et al reported a delicate infarcted myocardium at-risk score.According to their results,the MDCT-based myocardium at-risk score had a good correlation with the thallium 201 ST-segment elevation myocardial infarction-based summed difference score(r = 0.841,P < 0.001).They claimed that dual-phase MDCT is useful in detecting different patterns of obstructive lesions and the extent of myocardium at risk.In this commentary,we discuss the current status of the clinical application of MDCT in patients with myocardial infarction in relation to evaluating the myocardial perfusion defect,detecting reversible myocardial ischemia,assessing myocardial viability,estimating target lesion restenosis,and calculating of fractional flow reserve from MDCT.
