Adaptive ultrasonic measurement of blood vessel diameter and wall thickness: theory and experimental results

1998 ◽  
Vol 45 (3) ◽  
pp. 593-603 ◽  
Author(s):  
K. Rafii ◽  
J.S. Jaffe
Keyword(s):  
Blood Vessel ◽  
Wall Thickness ◽  
Vessel Diameter ◽  
Ultrasonic Measurement ◽  
Experimental Results

scholarly journals Supportive or information-processing functions of the mature protoplasmic astrocyte in the mammalian CNS? A critical appraisal

2007 ◽  
Vol 3 (3) ◽  
pp. 181-189 ◽  
Author(s):  
Harold K. Kimelberg
Keyword(s):  
Information Processing ◽  
Blood Vessel ◽  
Critical Appraisal ◽  
Vessel Diameter ◽  
Synaptic Activity ◽  
Metabolic Substrates ◽  
Processing Properties ◽  
New Evidence ◽  
The Brain ◽  
Domain Concept

AbstractIt has been proposed that astrocytes should no longer be viewed purely as support cells for neurons, such as providing a constant environment and metabolic substrates, but that they should also be viewed as being involved in affecting synaptic activity in an active way and, therefore, an integral part of the information-processing properties of the brain. This essay discusses the possible differences between a support and an instructive role, and concludes that any distinction has to be blurred. In view of this, and a brief overview of the nature of the data, the new evidence seems insufficient to conclude that the physiological roles of mature astrocytes go beyond a general support role. I propose a model of mature protoplasmic astrocyte function that is drawn from the most recent data on their structure, the domain concept and their syncytial characteristics, of an independent rather than integrative functioning of the ends of each process where the activities that affect synaptic activity and blood vessel diameter will be concentrated.

Towards Non-Invasive Pressure Assessment

2010 ◽  
Author(s):  
Nathalie Bijnens ◽  
Bart Beulen ◽  
Peter Brands ◽  
Marcel Rutten ◽  
Frans van de Vosse
Keyword(s):  
Wall Thickness ◽  
Vessel Wall ◽  
Biomechanical Properties ◽  
Vessel Diameter ◽  
Local Pressure ◽  
Vessel Wall Thickness ◽  
Non Invasive ◽  
Vascular Impedance ◽  
Vessel Wall Properties ◽  
Invasive Techniques

In clinical practice, ultrasound is frequently applied to non-invasively assess blood velocity, blood volume flow and blood vessel wall properties such as vessel wall thickness and vessel diameter waveforms. To convert these properties into relevant biomechanical properties that are related to cardiovascular disease (CVD), such as elastic modulus and compliance of the vessel wall, local pressure has to be assessed simultaneously with vessel wall thickness and vessel diameter waveforms. Additionally, accurate estimates of vascular impedance (transfer function between pressure and blood flow) can be a valuable tool for the estimation of the condition of the vessel, e.g., to diagnose stenosis. Studies of arterial impedance in humans, however, are hampered by the lack of reliable non-invasive techniques to simultaneously record pressure and flow locally as a function of time. Local pressure assessment together with flow has great potential for improving the ability to diagnose and monitor CVD.

scholarly journals FAU-Net: Fixup Initialization Channel Attention Neural Network for Complex Blood Vessel Segmentation

2020 ◽  
Vol 10 (18) ◽  
pp. 6280
Author(s):  
Dongjin Huang ◽  
Liwen Yin ◽  
Hao Guo ◽  
Wen Tang ◽  
Tao Ruan Wan
Keyword(s):  
Blood Vessel ◽  
Medical Image Segmentation ◽  
Experimental Results ◽  
Data Sets ◽  
Central Research ◽  
Attention Network ◽  
Multiple Feature ◽  
Network Flexibility ◽  
Crucial Information ◽  
Residual Block

Medical image segmentation based on deep learning is a central research issue in the field of computer vision. Many existing segmentation networks can achieve accurate segmentation using fewer data sets. However, they have disadvantages such as poor network flexibility and do not adequately consider the interdependence between feature channels. In response to these problems, this paper proposes a new de-normalized channel attention network, which uses an improved de-normalized residual block structure and a new channel attention module in the network for the segmentation of sophisticated vessels. The de-normalized network sends the extracted rough features to the channel attention network. The channel attention module can explicitly model the interdependence between channels and pay attention to the correlation with crucial information in multiple feature channels. It can focus on the channels with the most association with vital information among multiple feature channels, and get more detailed feature results. Experimental results show that the network proposed in this paper is feasible, is robust, can accurately segment blood vessels, and is particularly suitable for complex blood vessel structures. Finally, we compared and verified the network proposed in this paper with the state-of-the-art network and obtained better experimental results.

Ultrasonic measurement of post-mastectomy chest wall thickness

1970 ◽  
Vol 43 (511) ◽  
pp. 458-461 ◽  
Author(s):  
S. M. Jackson ◽  
G. P. Naylor ◽  
I. J. Kerby
Keyword(s):  
Chest Wall ◽  
Wall Thickness ◽  
Ultrasonic Measurement

Experimental and finite element study on the single-layer reticulated composite joints

2020 ◽  
Vol 23 (10) ◽  
pp. 2174-2187
Author(s):  
Liang Zheng ◽  
Cheng Qin ◽  
Hong Guo ◽  
Dapeng Zhang ◽  
Mingtan Zhou ◽  
...  
Keyword(s):  
Finite Element ◽  
Bearing Capacity ◽  
Axial Compression ◽  
Wall Thickness ◽  
Great Influence ◽  
Single Layer ◽  
Experimental Results ◽  
Steel Pipe ◽  
Cover Plate ◽  
Element Analysis

In this article, a new type of reticulated joint, named the steel–concrete composite reticulated shell joint, is proposed. The proposed reticulated shell joint consists of an inner circular steel pipe, an outer circular steel pipe, a steel cover plate, and internal concrete. Five test specimens were tested under axial compression. The variable study included the wall thickness of the inner and outer circular steel pipes and the radius of the inner circular steel pipe. The test specimens exhibited a high bearing capacity and good plastic deformation ability under axial compression. The test results show that the wall thickness of the outer circular steel pipe and the radius of the inner circular steel pipe have a great influence on the bearing capacity of the steel–concrete composite reticulated shell joint, while the wall thickness of the inner circular steel pipe has little influence on the bearing capacity of the steel–concrete composite reticulated shell joint. Based on the test of the steel–concrete composite reticulated shell joints under axial load, the three-dimensional nonlinear finite element model was used to analyze the mechanical properties of the steel–concrete composite reticulated shell joints under axial compression. The results of the finite element analysis showed good agreement with the experimental results. The formula for calculating the bearing capacity of the joint is derived. By comparing with the experimental results, the calculated results are basically consistent with the experimental results.

Associations Between Cardio–Ankle Vascular Index and Aortic Structure and Sclerosis Using Multidetector Computed Tomography

Angiology ◽  
2016 ◽  
Vol 68 (4) ◽  
pp. 330-338 ◽  
Author(s):  
Shigeo Horinaka ◽  
Hiroshi Yagi ◽  
Hiromichi Fukushima ◽  
Yoshimasa Shibata ◽  
Hiroshi Takeshima ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Multidetector Computed Tomography ◽  
Wall Thickness ◽  
Vessel Diameter ◽  
Aortic Pulse Wave Velocity ◽  
Aortic Atherosclerosis ◽  
Cross Sectional ◽  
Descending Aorta ◽  
Simple Index ◽  
Multiple Stepwise Regression Analysis

Aortic pulse wave velocity (PWV) has been accepted as the gold standard for arterial stiffness measurement. However, PWV depends on blood pressure (BP). To eliminate the BP dependency of PWV, the cardio–ankle vascular index (CAVI) was developed. This study aimed to define the relationship between CAVI and aortic atherosclerosis or structure on multidetector computed tomography (MDCT). Patients with (n = 49) or without (n = 49) coronary artery disease were studied. The lumen and vessel diameters and wall thickness were calculated from the cross-sectional area at the pulmonary bifurcation level by 64-slice MDCT. The CAVI was measured within 3 days before MDCT. Multivariate analysis showed that the vessel diameter of the ascending and descending aorta on MDCT depends on age, body surface area, and diastolic BP. The CAVI significantly correlated with the vessel diameter ( r = .453) and wall thickness ( r = .387) of the thoracic descending aorta ( P < .001, respectively). The CAVI was an independent predictor of the descending aortic wall thickness on multiple stepwise regression analysis. These data suggest that CAVI, a simple index, is useful for evaluating thoracic aortic atherosclerosis.

Potential of Tissue Engineered Blood Vessel as Model to Study Effect of Flow and Wall Thickness on Cellular Communication

2013 ◽  
Vol 3 (1) ◽  
pp. 39-46 ◽  
Author(s):  
V. M. Ragaseema ◽  
Soumya Columbus ◽  
Renu Ramesh ◽  
Lissy Krishnan
Keyword(s):  
Blood Vessel ◽  
Wall Thickness ◽  
Cellular Communication
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