BACKGROUND Pulsatile tinnitus(PT)is a potentially disabling symptom that has received increasing attention.Multiple causes of PT have been confirmed by targeted treatment.However,dynamic changes of related structures ...BACKGROUND Pulsatile tinnitus(PT)is a potentially disabling symptom that has received increasing attention.Multiple causes of PT have been confirmed by targeted treatment.However,dynamic changes of related structures in PT patients with multiple causes after stenting for ipsilateral transverse sinus stenosis(TSS)have not been previously reported.We report such a case and present postoperative computed tomography venography(CTV)follow-up findings to demonstrate the decreased sigmoid sinus diverticulum and bone remodeling.CASE SUMMARY A 45-year-old man suffered from left-sided PT for 15 years that was occasionally accompanied by headache and dizziness.Pre-operative CTV revealed left-sided sigmoid sinus wall anomalies(SSWAs),TSS,outflow dominance,large posterior condylar emissary vein,and an empty sella turcica.A cerebrospinal fluid pressure of 270 mmH2O was further detected.The sound disappeared immediately after stenting for ipsilateral TSS,with no recurrence during 2 years of follow-up.After the procedure,the patient underwent four consecutive CTV examinations.The diverticulum decreased 6 mo after the procedure with new bone remodeling.The density of the remodeled bone was further increased 1 year later,and a hardened edge was formed 2 years later.CONCLUSION PT associated with SSWAs,TSS,and idiopathic intracranial hypertension can be cured by stenting for TSS alone.And bone remodeling around SSWAs is a more significant finding.展开更多
BACKGROUND Pulsatile tinnitus(PT)is an annoying sound that can be eliminated with targeted treatment of the cause.However,the causes of PT have not been fully elucidated.CASE SUMMARY A 38-year-old woman with right-sid...BACKGROUND Pulsatile tinnitus(PT)is an annoying sound that can be eliminated with targeted treatment of the cause.However,the causes of PT have not been fully elucidated.CASE SUMMARY A 38-year-old woman with right-sided objective PT underwent preoperative computed tomography arteriography and venography(CTA/V).A 3.8 mm vine diploic vein(DV),which passed through the mastoid air cells posteriorly in a dehiscent canal and was continuous with the transverse-sigmoid sinus,was thought to be the causative finding.Four-dimensional flow magnetic resonance(4D flow MR)imaging showed that the blood in the DV flowed toward the transverse-sigmoid sinus.The closer the blood was to the transverse-sigmoid sinus,the higher the velocity.No vortex or turbulence was found in the DV or adjacent transverse sinus.The sound was eliminated immediately after ligation of the DV with no recurrence during a three-month follow-up.No flow signal of the DV was noted on postoperative 4D flow MR.CONCLUSION A DV may be a treatable cause of PT.CTA/V and 4D flow MR could be utilized to determine the morphological and hemodynamic characteristics of the DV.展开更多
The filtration performance of the moving bed granular filter with axial flow (MBGF-AF) is investigated through a large cold experiment. The effect of different operation parameters on the filtration performance (colle...The filtration performance of the moving bed granular filter with axial flow (MBGF-AF) is investigated through a large cold experiment. The effect of different operation parameters on the filtration performance (collection efficiency, pressure drop) of the axial-flow moving bed filter is investigated in combination with the dust deposition effect and the mechanism of trapping dust by the capturing particles. The results show that the collection efficiency of MBGF-AF is enhanced by decreasing the superficial gas velocity, increasing the inlet dust concentration properly, or decreasing the moving velocity of the capturing particles. A model covering the above operation parameters is established to calculate the collection efficiency of the moving bed granular filter. It is used in a wide range of operating parameters for the MBGFs.展开更多
To the Editor: Non-arteritic anterior ischemic optic neuropathy (NAION), characterized by a sudden onset of unilateral painless visual loss and a swollen optic disc, is the most common form of acute optic neuropathy i...To the Editor: Non-arteritic anterior ischemic optic neuropathy (NAION), characterized by a sudden onset of unilateral painless visual loss and a swollen optic disc, is the most common form of acute optic neuropathy in patients over 50 years of age.[1] The pathogenesis of NAION remains unclear, but most histopathological studies support the concept of vasculopathic occlusion in the region of the short posterior ciliary arteries.[2] Functional magnetic resonance imaging (fMRI) is one of the most widely used non-invasive techniques for measuring brain function over time in vivo. To the best of our knowledge, only one study has investigated the effects of stimulating the affected eye in the extra-visual areas in NAION in humans.[3]However, this previous study only examined task-state fMRI, and lacked a measure of resting-state fMRI (rs-fMRI). Thus, it remains unclear whether regional spontaneous brain changes are limited to the visual system.展开更多
Introduction Upper abdominal magnetic resonance(MR)imaging is appropriate for body composition analysis.111 Especially for individuals with obesity,it is of great value to quantify the hepatic proton density fat fract...Introduction Upper abdominal magnetic resonance(MR)imaging is appropriate for body composition analysis.111 Especially for individuals with obesity,it is of great value to quantify the hepatic proton density fat fraction(PDFF)and the amount of abdominal adipose tissue during clinical evaluation and for research on obesity-related risks.Analytical results may be used to determine the optimal choice of surgical procedure and evaluate treatment outcomes.Multiple artificial intelligence(Al)algorithms and systems have been developed for the automated measurement of body composition.The basis of Al development and application is to have uniform standards for clinical data acquisition and management.The uneven quality ofMR images is one ofthe major obstacles to Al system development and analytical results.A standardized process of MR scanning and clinical data management is urgently needed.展开更多
基金The Beijing Scholar 2015and the National Natural Science Foundation of China,No.61931013,No.81701644,and No.61801311.
文摘BACKGROUND Pulsatile tinnitus(PT)is a potentially disabling symptom that has received increasing attention.Multiple causes of PT have been confirmed by targeted treatment.However,dynamic changes of related structures in PT patients with multiple causes after stenting for ipsilateral transverse sinus stenosis(TSS)have not been previously reported.We report such a case and present postoperative computed tomography venography(CTV)follow-up findings to demonstrate the decreased sigmoid sinus diverticulum and bone remodeling.CASE SUMMARY A 45-year-old man suffered from left-sided PT for 15 years that was occasionally accompanied by headache and dizziness.Pre-operative CTV revealed left-sided sigmoid sinus wall anomalies(SSWAs),TSS,outflow dominance,large posterior condylar emissary vein,and an empty sella turcica.A cerebrospinal fluid pressure of 270 mmH2O was further detected.The sound disappeared immediately after stenting for ipsilateral TSS,with no recurrence during 2 years of follow-up.After the procedure,the patient underwent four consecutive CTV examinations.The diverticulum decreased 6 mo after the procedure with new bone remodeling.The density of the remodeled bone was further increased 1 year later,and a hardened edge was formed 2 years later.CONCLUSION PT associated with SSWAs,TSS,and idiopathic intracranial hypertension can be cured by stenting for TSS alone.And bone remodeling around SSWAs is a more significant finding.
基金Supported by National Natural Science Foundation of China,No.61931013 and No.61801311.
文摘BACKGROUND Pulsatile tinnitus(PT)is an annoying sound that can be eliminated with targeted treatment of the cause.However,the causes of PT have not been fully elucidated.CASE SUMMARY A 38-year-old woman with right-sided objective PT underwent preoperative computed tomography arteriography and venography(CTA/V).A 3.8 mm vine diploic vein(DV),which passed through the mastoid air cells posteriorly in a dehiscent canal and was continuous with the transverse-sigmoid sinus,was thought to be the causative finding.Four-dimensional flow magnetic resonance(4D flow MR)imaging showed that the blood in the DV flowed toward the transverse-sigmoid sinus.The closer the blood was to the transverse-sigmoid sinus,the higher the velocity.No vortex or turbulence was found in the DV or adjacent transverse sinus.The sound was eliminated immediately after ligation of the DV with no recurrence during a three-month follow-up.No flow signal of the DV was noted on postoperative 4D flow MR.CONCLUSION A DV may be a treatable cause of PT.CTA/V and 4D flow MR could be utilized to determine the morphological and hemodynamic characteristics of the DV.
基金supported by National Natural Science Foundation of China(U1862202).
文摘The filtration performance of the moving bed granular filter with axial flow (MBGF-AF) is investigated through a large cold experiment. The effect of different operation parameters on the filtration performance (collection efficiency, pressure drop) of the axial-flow moving bed filter is investigated in combination with the dust deposition effect and the mechanism of trapping dust by the capturing particles. The results show that the collection efficiency of MBGF-AF is enhanced by decreasing the superficial gas velocity, increasing the inlet dust concentration properly, or decreasing the moving velocity of the capturing particles. A model covering the above operation parameters is established to calculate the collection efficiency of the moving bed granular filter. It is used in a wide range of operating parameters for the MBGFs.
文摘To the Editor: Non-arteritic anterior ischemic optic neuropathy (NAION), characterized by a sudden onset of unilateral painless visual loss and a swollen optic disc, is the most common form of acute optic neuropathy in patients over 50 years of age.[1] The pathogenesis of NAION remains unclear, but most histopathological studies support the concept of vasculopathic occlusion in the region of the short posterior ciliary arteries.[2] Functional magnetic resonance imaging (fMRI) is one of the most widely used non-invasive techniques for measuring brain function over time in vivo. To the best of our knowledge, only one study has investigated the effects of stimulating the affected eye in the extra-visual areas in NAION in humans.[3]However, this previous study only examined task-state fMRI, and lacked a measure of resting-state fMRI (rs-fMRI). Thus, it remains unclear whether regional spontaneous brain changes are limited to the visual system.
基金supported by the National Natural Science Foundation of China(No.62171297)the Capital's Funds for Health Improvement and Research(No.2020-1-2021)the Beijing Hospitals Authority Clinical Medicine Development of Special Funding Support(No.ZYLX202101)。
文摘Introduction Upper abdominal magnetic resonance(MR)imaging is appropriate for body composition analysis.111 Especially for individuals with obesity,it is of great value to quantify the hepatic proton density fat fraction(PDFF)and the amount of abdominal adipose tissue during clinical evaluation and for research on obesity-related risks.Analytical results may be used to determine the optimal choice of surgical procedure and evaluate treatment outcomes.Multiple artificial intelligence(Al)algorithms and systems have been developed for the automated measurement of body composition.The basis of Al development and application is to have uniform standards for clinical data acquisition and management.The uneven quality ofMR images is one ofthe major obstacles to Al system development and analytical results.A standardized process of MR scanning and clinical data management is urgently needed.
