Gastric schwannomas are rare mesenchymal tumors of the gastrointestinal tract.They are usually misdiagnosed as other submucosal tumors preoperatively.Experience of the imaging features of gastric schwannomas is extrem...Gastric schwannomas are rare mesenchymal tumors of the gastrointestinal tract.They are usually misdiagnosed as other submucosal tumors preoperatively.Experience of the imaging features of gastric schwannomas is extremely limited.In this report,we summarize the features of a series of endoscopic ultrasound(EUS) images of gastric schwannomas in an effort to improve the diagnosis and differential diagnosis rate.We retrospectively reviewed the endosonographic features of four patients with gastric schwannomas and their computed tomography imaging results.Gastric schwannomas had heterogeneous hypoechogenicity or isoechogenicity,and a well-demarcated margin.The tumors originated from the fourth layer.Cystic changes and calcification were uncommon.Marginal hypoechoic haloes were observed in two patients.The results described here were different from those of previous studies.In the EUS evaluation,the internal echogenicity of gastric schwannomas was heterogeneous and low,but slightly higher than that of muscularis pro-pria.These features might help us differentiate gastric schwannomas from other submucosal tumors.Further investigation is needed to differentiate these mesenchymal tumors.展开更多
Presents a study that examined the application of an overlapping domain decomposition method to the solution of time-dependent convection-diffusion problems. Background on the Schwartz alternating procedure; Applicati...Presents a study that examined the application of an overlapping domain decomposition method to the solution of time-dependent convection-diffusion problems. Background on the Schwartz alternating procedure; Application of two kinds of Schwartz alternating procedure to solve the numerical approximation problem; Numerical results.展开更多
文摘Gastric schwannomas are rare mesenchymal tumors of the gastrointestinal tract.They are usually misdiagnosed as other submucosal tumors preoperatively.Experience of the imaging features of gastric schwannomas is extremely limited.In this report,we summarize the features of a series of endoscopic ultrasound(EUS) images of gastric schwannomas in an effort to improve the diagnosis and differential diagnosis rate.We retrospectively reviewed the endosonographic features of four patients with gastric schwannomas and their computed tomography imaging results.Gastric schwannomas had heterogeneous hypoechogenicity or isoechogenicity,and a well-demarcated margin.The tumors originated from the fourth layer.Cystic changes and calcification were uncommon.Marginal hypoechoic haloes were observed in two patients.The results described here were different from those of previous studies.In the EUS evaluation,the internal echogenicity of gastric schwannomas was heterogeneous and low,but slightly higher than that of muscularis pro-pria.These features might help us differentiate gastric schwannomas from other submucosal tumors.Further investigation is needed to differentiate these mesenchymal tumors.
基金Project supported by the Natural Science Foundation of China Grant No. 19771050, No. 10171052 by the Foundation of National Key Laboratory of Computational Physics.
文摘Presents a study that examined the application of an overlapping domain decomposition method to the solution of time-dependent convection-diffusion problems. Background on the Schwartz alternating procedure; Application of two kinds of Schwartz alternating procedure to solve the numerical approximation problem; Numerical results.