Small-bowel carcinoid tumors are the most common form(42%) of gastrointestinal carcinoids, which by themselves comprise 70% of neuroendocrine tumors. Although primary small bowel neoplasms are overall rare(3%-6% of al...Small-bowel carcinoid tumors are the most common form(42%) of gastrointestinal carcinoids, which by themselves comprise 70% of neuroendocrine tumors. Although primary small bowel neoplasms are overall rare(3%-6% of all gastrointestinal neoplasms), carcinoids still represent the second most common(20%-30%) primary small-bowel malignancy after small bowel adenocarcinoma. Their imaging evaluation is often challenging. State-of-the-art high-resolution multiphasic computed tomography together with advanced postprocessing methods provides an excellent tool for their depiction. The manifold interactive parameter choices however require knowledge of when to use which technique. Here, we discuss the imaging appearance and evaluation of duodenal, jejunal and ileal carcinoid tumors, including the imaging features of the primary tumor, locoregional mesenteric nodal metastases, and distant metastatic disease. A protocol for optimal lesion detection is presented, including the use of computed tomography enterography, volume acquisition, computed tomography angiography and three-dimensional mapping. Imaging findings are illustrated with a series of challenging cases which illustrate the spectrum of possible disease in the small bowel and mesentery, the range of possible appearances in the bowel itself on multiphase data and extraluminal findings such as the desmoplastic reaction in mesentery and hypervascular liver metastases. Typical imaging pitfalls and pearls are illustrated.展开更多
Recently,the simplified spherical harmonics equations(SP)model has at tracted much att entionin modeling the light propagation in small tissue ggeometriesat visible and near-infrared wave-leng ths.In this paper,we rep...Recently,the simplified spherical harmonics equations(SP)model has at tracted much att entionin modeling the light propagation in small tissue ggeometriesat visible and near-infrared wave-leng ths.In this paper,we report an eficient numerical method for fluorescence moleeular tom-ography(FMT)that combines the advantage of SP model and adaptive hp finite elementmethod(hp-FEM).For purposes of comparison,hp-FEM and h-FEM are,respectively applied tothe reconstruction pro cess with diffusion approximation and SPs model.Simulation experiments on a 3D digital mouse atlas and physical experiments on a phantom are designed to evaluate thereconstruction methods in terms of the location and the reconstructed fluorescent yield.Theexperimental results demonstrate that hp-FEM with SPy model,yield more accurate results thanh-FEM with difusion approximation model does.The phantom experiments show the potentialand feasibility of the proposed approach in FMT applications.展开更多
Pancreatic cancer(PC)remains one of the deadliest cancers worldwide,and has a poor,five-year survival rate of 5%.Although complete surgical resection is the only curative therapy for pancreatic cancer,less than20%of n...Pancreatic cancer(PC)remains one of the deadliest cancers worldwide,and has a poor,five-year survival rate of 5%.Although complete surgical resection is the only curative therapy for pancreatic cancer,less than20%of newly-diagnosed patients undergo surgical resection with a curative intent.Due to the lack of early symptoms and the tendency of pancreatic adenocarcinoma to invade adjacent structures or to metastasize at an early stage,many patients with pancreatic cancer already have advanced disease at the time of their diagnosis and,therefore,there is a high mortality rate.To improve the patient survival rate,early detection of PC is critical.The diagnosis of PC relies on computed tomography(CT)and/or magnetic resonance imaging(MRI)with magnetic resonance cholangiopancreatography(MRCP),or biopsy or fine-needle aspiration using endoscopic ultrasound(EUS).Although multi-detector row computed tomography currently has a major role in the evaluation of PC,MRI with MRCP facilitates better detection of tumors at an early stage by allowing a comprehensive analysis of the morphological changes of the pancreas parenchyma and pancreatic duct.The diagnosis could be improved using positron emission tomography techniques in special conditions in which CT and EUS are not completely diagnostic.It is essential for clinicians to understand the advantages and disadvantages of the various pancreatic imaging modalities in order to be able to make optimal treatment and management decisions.Our study investigates the current role and innovative techniques of pancreatic imaging focused on the detection of pancreatic cancer.展开更多
Esophageal squamous cell carcinoma(ESCC) is known for its rapid progression and poor outcomes. China has the highest incidence and mortality in the world. Diagnoses made at early stages and accurate staging are associ...Esophageal squamous cell carcinoma(ESCC) is known for its rapid progression and poor outcomes. China has the highest incidence and mortality in the world. Diagnoses made at early stages and accurate staging are associated with better outcomes, all of which can play a significant role in the selection of treatment protocols. ESCC is staged according to the widely accepted TNM system. Common imaging modalities used in staging ESCC before treatment include endoscopy, computed tomography(CT), positron emission tomography(PET) and magnetic resonance imaging(MRI). Endoscopic ultrasound is useful for staging tumor depth and nodal status. Narrow band imaging is valuable for early stage disease assessment. CT and PET provide additional valuable information regarding node and metastasis staging. The ability of MRI to delineate ESCC is continuously being improved and adds information regarding locoregional status to routine examinations.展开更多
文摘Small-bowel carcinoid tumors are the most common form(42%) of gastrointestinal carcinoids, which by themselves comprise 70% of neuroendocrine tumors. Although primary small bowel neoplasms are overall rare(3%-6% of all gastrointestinal neoplasms), carcinoids still represent the second most common(20%-30%) primary small-bowel malignancy after small bowel adenocarcinoma. Their imaging evaluation is often challenging. State-of-the-art high-resolution multiphasic computed tomography together with advanced postprocessing methods provides an excellent tool for their depiction. The manifold interactive parameter choices however require knowledge of when to use which technique. Here, we discuss the imaging appearance and evaluation of duodenal, jejunal and ileal carcinoid tumors, including the imaging features of the primary tumor, locoregional mesenteric nodal metastases, and distant metastatic disease. A protocol for optimal lesion detection is presented, including the use of computed tomography enterography, volume acquisition, computed tomography angiography and three-dimensional mapping. Imaging findings are illustrated with a series of challenging cases which illustrate the spectrum of possible disease in the small bowel and mesentery, the range of possible appearances in the bowel itself on multiphase data and extraluminal findings such as the desmoplastic reaction in mesentery and hypervascular liver metastases. Typical imaging pitfalls and pearls are illustrated.
基金supported by the National Natural Science Foundation of China(Grant No.61372046)the Research Fund for the Doctoral Program of Higher Education of China(New Teachers)(Grant No.20116101120018)+6 种基金the China Postdoctoral Science Foundation Funded Project(Grant Nos.2011M501467 and 2012T50814)the Natural Science Basic Research Plan in Shaanxi Province of China(Grant No.2011JQ1006)the Fundamental Research Funds for the Central Universities(Grant No.GK201302007)Science and Technology Plan Program,in Shaanxi Province of China(Grant Nos.2012 KJXX-29 and 2013K12-20-12)the Science and Technology Plan Program in Xian of China(Grant No.CXY1348(2))the.GraduateInovation Project of Northwest University(Grant No.YZZ12093)the Seience and Technology Program of Educational Committee,of Shaanxi Province of China(Grant No.12JK0729).
文摘Recently,the simplified spherical harmonics equations(SP)model has at tracted much att entionin modeling the light propagation in small tissue ggeometriesat visible and near-infrared wave-leng ths.In this paper,we report an eficient numerical method for fluorescence moleeular tom-ography(FMT)that combines the advantage of SP model and adaptive hp finite elementmethod(hp-FEM).For purposes of comparison,hp-FEM and h-FEM are,respectively applied tothe reconstruction pro cess with diffusion approximation and SPs model.Simulation experiments on a 3D digital mouse atlas and physical experiments on a phantom are designed to evaluate thereconstruction methods in terms of the location and the reconstructed fluorescent yield.Theexperimental results demonstrate that hp-FEM with SPy model,yield more accurate results thanh-FEM with difusion approximation model does.The phantom experiments show the potentialand feasibility of the proposed approach in FMT applications.
文摘Pancreatic cancer(PC)remains one of the deadliest cancers worldwide,and has a poor,five-year survival rate of 5%.Although complete surgical resection is the only curative therapy for pancreatic cancer,less than20%of newly-diagnosed patients undergo surgical resection with a curative intent.Due to the lack of early symptoms and the tendency of pancreatic adenocarcinoma to invade adjacent structures or to metastasize at an early stage,many patients with pancreatic cancer already have advanced disease at the time of their diagnosis and,therefore,there is a high mortality rate.To improve the patient survival rate,early detection of PC is critical.The diagnosis of PC relies on computed tomography(CT)and/or magnetic resonance imaging(MRI)with magnetic resonance cholangiopancreatography(MRCP),or biopsy or fine-needle aspiration using endoscopic ultrasound(EUS).Although multi-detector row computed tomography currently has a major role in the evaluation of PC,MRI with MRCP facilitates better detection of tumors at an early stage by allowing a comprehensive analysis of the morphological changes of the pancreas parenchyma and pancreatic duct.The diagnosis could be improved using positron emission tomography techniques in special conditions in which CT and EUS are not completely diagnostic.It is essential for clinicians to understand the advantages and disadvantages of the various pancreatic imaging modalities in order to be able to make optimal treatment and management decisions.Our study investigates the current role and innovative techniques of pancreatic imaging focused on the detection of pancreatic cancer.
文摘Esophageal squamous cell carcinoma(ESCC) is known for its rapid progression and poor outcomes. China has the highest incidence and mortality in the world. Diagnoses made at early stages and accurate staging are associated with better outcomes, all of which can play a significant role in the selection of treatment protocols. ESCC is staged according to the widely accepted TNM system. Common imaging modalities used in staging ESCC before treatment include endoscopy, computed tomography(CT), positron emission tomography(PET) and magnetic resonance imaging(MRI). Endoscopic ultrasound is useful for staging tumor depth and nodal status. Narrow band imaging is valuable for early stage disease assessment. CT and PET provide additional valuable information regarding node and metastasis staging. The ability of MRI to delineate ESCC is continuously being improved and adds information regarding locoregional status to routine examinations.
