scholarly journals A Blood Flow Volume Linear Inversion Model Based on Electromagnetic Sensor for Predicting the Rate of Arterial Stenosis

Sensors ◽  
2019 ◽  
Vol 19 (13) ◽  
pp. 3006
Author(s):  
Dan Yang ◽  
Yan-jun Liu ◽  
Bin Xu ◽  
Yun-hui Duo
Keyword(s):  
Magnetic Field ◽  
Finite Element ◽  
Blood Flow ◽  
Uniform Magnetic Field ◽  
Geometric Model ◽  
Arterial Stenosis ◽  
Flow Volume ◽  
Linear Inversion ◽  
Inversion Model ◽  
Blood Flow Volume

This paper presents a mathematical model of measuring blood flow based on electromagnetic induction for predicting the rate of arterial stenosis. Firstly, an electrode sensor was used to collect the induced potential differences from human skin surface in a uniform magnetic field. Then, the inversion matrix was constructed by the weight function theory and finite element method. Next, the blood flow volume inversion model was constructed by combining the induction potential differences and inversion matrix. Finally, the rate of arterial stenosis was predicted based on mathematical relationship between blood flow and the area of arterial stenosis. To verify the accuracy of the model, a uniform magnetic field distribution of Helmholtz coil and a 3D geometric model of the ulnar artery of the forearm with different rates of stenosis were established in COMSOL, a finite element analysis software. Simulation results showed that the inversion model had high accuracy in the measurement of blood flow and the prediction of rate of stenosis, and is of great significance for the early diagnosis of arterial stenosis and other vessel diseases.

Evaluation of the effects of an AC magnetic field exposure on blood flow volume by using a 2D laser speckle flowmetry．

2018 ◽  
Vol 2018.28 (0) ◽  
pp. 2206
Author(s):  
Nur Izyana Faradila Binti AZMI ◽  
Hideyuki OKANO ◽  
Tsukasa KONDO ◽  
Hiromi ISHIWATARI ◽  
Keiichi WATANUKI
Keyword(s):  
Magnetic Field ◽  
Blood Flow ◽  
Laser Speckle ◽  
Flow Volume ◽  
Field Exposure ◽  
Magnetic Field Exposure ◽  
Ac Magnetic Field ◽  
Blood Flow Volume

scholarly journals P07.04: Uterine artery blood flow volume is reduced in human pregnancies with increase utero-placental downstream impedance

2006 ◽  
Vol 28 (4) ◽  
pp. 569-569
Author(s):  
S. Boito ◽  
S. Rigano ◽  
G. Pennati ◽  
L. Mandia ◽  
A. Padoan ◽  
...  
Keyword(s):  
Blood Flow ◽  
Uterine Artery ◽  
Flow Volume ◽  
Artery Blood Flow ◽  
Blood Flow Volume

Cerebral Blood Flow Volume in Posterior Circulation Ischemic Disorders

2021 ◽  
pp. 154431672110539
Author(s):  
Anastasiya Yu. Vishnyakova ◽  
Nataliya M. Medvedeva ◽  
Alexander B. Berdalin ◽  
Svetlana E. Lelyuk ◽  
Vladimir G. Lelyuk
Keyword(s):  
Blood Flow ◽  
Healthy Volunteers ◽  
Internal Carotid ◽  
Duplex Sonography ◽  
Posterior Circulation ◽  
Control Group ◽  
Vertebrobasilar Insufficiency ◽  
Flow Volume ◽  
Blood Flow Volume ◽  
Vertebral Arteries

Objective: The aim of this study was to determine blood flow volume (BFV) in the normal state and its features in patients with acute posterior circulation ischemic strokes (PCIS) and vertebrobasilar insufficiency (VBI) using color duplex sonography (DS).Methods: The study included DS data from 96 patients with verified PCIS (66 men and 30 women, aged 64±13 years) and 29 adults with VBI (17 men and 12 women, aged 66±11 years). The control group consisted of 65 healthy male volunteers of different ages.Results: In asymptomatic healthy volunteers, there was a significant decrease in BFV in the internal carotid artery (ICA) with age (502 ml/min in young people, 465 ml/min in the older subgroup) with rS = −0.24 ( p = 0.05), and the aggregated BFV in the vertebral arteries (VAs) turned out to be almost constant (141–143 ml/min). In patients with VBI, the aggregated BFV in the VAs (144 ml/min) did not differ from that in healthy volunteers, but the BFV values in the ICAs were significantly lower (325 ml/min). In patients with PCIS, the aggregated BFV in the ICAs was also significantly lower (399 ml/min) than in the control group but did not significantly differ from that in patients with VBI. In patients with PCIS, there was a significant decrease in the aggregated BFV in the VAs (105 ml/min), which distinguished this group from other examined patients.Conclusions: A significant decrease the BFV in the VA was observed only in patients with PCIS and was associated with the presence of steno-occlusive diseases (SOD) more often in the left VA. Patients with VBI had the most pronounced decrease in BFV in the ICA.

Blood flow, volume, and transit time in the pulmonary microvasculature using laser-Doppler

1994 ◽  
Vol 76 (6) ◽  
pp. 2643-2650 ◽  
Author(s):  
T. S. Hakim ◽  
E. Gilbert ◽  
E. M. Camporesi
Keyword(s):  
Blood Flow ◽  
Blood Volume ◽  
Transit Time ◽  
Flow Rate ◽  
Venous Pressure ◽  
Laser Doppler ◽  
Flow Volume ◽  
Doppler Flowmetry ◽  
Blood Flow Volume ◽  
Wide Range

Capillary transit time is determined by the ratio of capillary volume to flow rate. Exercise-induced hypoxemia is thought to occur because of the short transit time of erythrocytes in capillaries. The effect of flow rate on capillary volume (recruitment vs. distension) is controversial. In a perfused left lower lobe preparation in canine lungs, we used laser-Doppler flowmetry (model ALF21R) to monitor changes in blood flow, volume, and transit time in the microvasculature near the subpleural surface. Changes in total flow, blood volume, and total transit time (tt) were also measured. The results showed that microvascular volume approached maximum when flow rate was at resting value (0.4 l/min) and pressure in the pulmonary artery was > 6 mmHg relative to the level of the capillaries. In contrast, the total blood volume increased gradually over a wide range of flow rates. When flow increased 4.2 times (from 155 to 650 ml/min), tt decreased from 7.32 to 3.53 s; meanwhile, microvascular flow increased from 6.0 to 12.7 units and microvascular transit time decreased from 3.14 to 1.81 units. The changes in microvascular volume and transit time were essentially independent of whether the venous pressure was higher or lower than alveolar pressure. At very high flow (6–10 times resting value), tt fell gradually to approximately 1 s. Direct monitoring of transit time with the laser-Doppler also revealed a gradual decline in microvascular transit time as flow rate increased from 2 to 10 times the normal flow. (ABSTRACT TRUNCATED AT 250 WORDS)

Sign in / Sign up

Export Citation Format

Share Document