BACKGROUND Indwelling inferior vena cava(IVC)filters might cause various complications,including filter penetration,filter fracture,filter migration,and thrombosis of the IVC.Penetration and migration complications ar...BACKGROUND Indwelling inferior vena cava(IVC)filters might cause various complications,including filter penetration,filter fracture,filter migration,and thrombosis of the IVC.Penetration and migration complications are common,while a caudal migrated double-basket filter with associated infected iliac pseudoaneurysm has seldom been reported.CASE SUMMARY We report a 64-year-old female admitted for sudden onset of severe right abdominal pain after IVC filter placement for 3 mo.The patient had a history of failed endovascular IVC filter retrieval.Computed tomography showed that the retrieval hook of the filter penetrated the right common iliac artery and vein,leading to right iliac artery pseudoaneurysm accompanied by right ureteral obstruction with ipsilateral hydronephrosis,and bilateral iliac veins were occluded.Emergency open repair was performed to remove the IVC filter,the right iliac pseudoaneurysm,and the compromised segments of the iliac veins and IVC with right common iliac artery reconstruction.Staphylococcus aureus was isolated from the tissue culture.The patient was discharged on postoperative day 12 with anticoagulation therapy and antibiotic therapy after discharge.Six-month follow-up computed tomography revealed that the right common iliac artery was patent,and only mild hydronephrosis was detected.CONCLUSION An indwelling IVC filter,even‘embedded’within organized thrombus,could still cause life-threatening complications.Open procedures remain the last resort for IVC filters with severe complications.展开更多
Review of X-ray dark-field imaging under development is presented. Its goal is its application to clinical diagnosis of organs that have been invisible by the ordinary techniques. In order to clinically visualize tiss...Review of X-ray dark-field imaging under development is presented. Its goal is its application to clinical diagnosis of organs that have been invisible by the ordinary techniques. In order to clinically visualize tissues in detail one needs high contrast and high spatial resolution say ～50 μm. This X-ray optics comprises a Bragg asymmetric monochro-collimator and a Bragg case or a Laue case filter with capability of analyzing angle in a parallel position. Their diffraction index is 4,4,0 and the X-ray energy 35 keV (λ= 0.0354 nm). The filter has 0.6 mm thickness in the Bragg case or 1.075 mm or 2.15 mm thickness in the Laue case. Under this condition only the refracted X-rays from object can transmit through the filter while the beam that may receive absorption and/or phase change will not. Soft tissues at human joints thus taken show high contrast images so that the DFI is promising for clinical diagnosis. Preliminary X-ray absorption images of another clinical candidates of ear bones are also shown.展开更多
This paper presents the derivation of Gauss-Newton filter in linear cases and an analysis of its properties. Based on the minimum variance theorem, the Gauss-Newton filter is constructed and derived, including its sta...This paper presents the derivation of Gauss-Newton filter in linear cases and an analysis of its properties. Based on the minimum variance theorem, the Gauss-Newton filter is constructed and derived, including its state transition equation, observation equation and filtering process. Then, the delicate relationship between the Gauss-Aitken filter and the Kalman filter is discussed and it is verified that without process noise the two filters are equivalent. Finally, some simulations are conducted. The result shows that the Gauss-Aitken filter is superior to the Kalman filter in some aspects.展开更多
基金Supported by the Sichuan Foundation of Science and Technology,No.2020YFS0247。
文摘BACKGROUND Indwelling inferior vena cava(IVC)filters might cause various complications,including filter penetration,filter fracture,filter migration,and thrombosis of the IVC.Penetration and migration complications are common,while a caudal migrated double-basket filter with associated infected iliac pseudoaneurysm has seldom been reported.CASE SUMMARY We report a 64-year-old female admitted for sudden onset of severe right abdominal pain after IVC filter placement for 3 mo.The patient had a history of failed endovascular IVC filter retrieval.Computed tomography showed that the retrieval hook of the filter penetrated the right common iliac artery and vein,leading to right iliac artery pseudoaneurysm accompanied by right ureteral obstruction with ipsilateral hydronephrosis,and bilateral iliac veins were occluded.Emergency open repair was performed to remove the IVC filter,the right iliac pseudoaneurysm,and the compromised segments of the iliac veins and IVC with right common iliac artery reconstruction.Staphylococcus aureus was isolated from the tissue culture.The patient was discharged on postoperative day 12 with anticoagulation therapy and antibiotic therapy after discharge.Six-month follow-up computed tomography revealed that the right common iliac artery was patent,and only mild hydronephrosis was detected.CONCLUSION An indwelling IVC filter,even‘embedded’within organized thrombus,could still cause life-threatening complications.Open procedures remain the last resort for IVC filters with severe complications.
文摘Review of X-ray dark-field imaging under development is presented. Its goal is its application to clinical diagnosis of organs that have been invisible by the ordinary techniques. In order to clinically visualize tissues in detail one needs high contrast and high spatial resolution say ～50 μm. This X-ray optics comprises a Bragg asymmetric monochro-collimator and a Bragg case or a Laue case filter with capability of analyzing angle in a parallel position. Their diffraction index is 4,4,0 and the X-ray energy 35 keV (λ= 0.0354 nm). The filter has 0.6 mm thickness in the Bragg case or 1.075 mm or 2.15 mm thickness in the Laue case. Under this condition only the refracted X-rays from object can transmit through the filter while the beam that may receive absorption and/or phase change will not. Soft tissues at human joints thus taken show high contrast images so that the DFI is promising for clinical diagnosis. Preliminary X-ray absorption images of another clinical candidates of ear bones are also shown.
文摘This paper presents the derivation of Gauss-Newton filter in linear cases and an analysis of its properties. Based on the minimum variance theorem, the Gauss-Newton filter is constructed and derived, including its state transition equation, observation equation and filtering process. Then, the delicate relationship between the Gauss-Aitken filter and the Kalman filter is discussed and it is verified that without process noise the two filters are equivalent. Finally, some simulations are conducted. The result shows that the Gauss-Aitken filter is superior to the Kalman filter in some aspects.
