Visualization of Blood Vessels in Two-Dimensional and Three-Dimensional Environments for Vascular Stereology in the Brain

2013 ◽  
pp. 139-152
Author(s):  
Zerina Lokmic
Keyword(s):  
Blood Vessels ◽  
Three Dimensional ◽  
Two Dimensional ◽  
The Brain

scholarly journals Twenty-week Brain Vascularity by Transvaginal 3D HDlive Flow

2016 ◽  
Vol 10 (3) ◽  
pp. 203-204
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Blood Vessels ◽  
Peripheral Blood ◽  
Obstet Gynecol ◽  
Three Dimensional ◽  
Flow Imaging ◽  
Functional Information ◽  
Realistic Rendering ◽  
The Brain

ABSTRACT Recent advances of three-dimensional (3D) Doppler application is HDlive flow providing a realistic rendering of fine peripheral blood vessels, such as vascularity of the lung, brain, and eyeballs. The picture of the month demonstrates an oblique– sagittal view of the brain vascularity. Flow imaging can add both angiostructural and functional information to structural findings of normal and abnormal central nervous system. How to cite this article Pooh RK. 20-week Brain Vascularity by Transvaginal 3D HDlive Flow. Donald School J Ultrasound Obstet Gynecol 2016;10(3):203-204.

A Model for Heat Transfer From Embedded Blood Vessels in Two-Dimensional Tissue Preparations

1995 ◽  
Vol 117 (1) ◽  
pp. 64-73 ◽  
Author(s):  
Liang Zhu ◽  
Sheldon Weinbaum
Keyword(s):  
Heat Transfer ◽  
Blood Vessels ◽  
Three Dimensional ◽  
Tissue Preparation ◽  
Basic Solution ◽  
Two Dimensional ◽  
Dimensional Solution ◽  
Tissue Conductivity ◽  
Thermal Equilibration ◽  
Insight Into

Two-dimensional microvascular tissue preparations have been extensively used to study blood flow in the microcirculation, and, most recently, the mechanism of thermal equilibration between thermally significant countercurrent artery-vein pairs. In this paper, an approximate three-dimensional solution for the heat transfer from a periodic array of blood vessels in a tissue preparation of uniform thickness with surface convection is constructed using a newly derived fundamental solution for a Green’s function for this flow geometry. This approximate solution is exact when the ratio K′ of the blood to tissue conductivity is unity and a highly accurate approximation when K′ ≠ 1. This basic solution is applied to develop a model for the heat transfer from a countercurrent artery-vein pair in an exteriorized rat cremaster muscle preparation. The numerical results provide important new insight into the design of microvascular experiments in which the axial variation of the thermal equilibration in microvessels can be measured for the first time. The solutions also provide new insight into the design of fluted fins and microchips that are convectively cooled by internal pores.

scholarly journals On Buckling Morphogenesis

2016 ◽  
Vol 138 (2) ◽  
Author(s):  
Celeste M. Nelson
Keyword(s):  
Three Dimensional ◽  
Mechanical Forces ◽  
Two Dimensional ◽  
One Dimensional ◽  
Epithelial Tissues ◽  
Epithelial Sheets ◽  
The Brain ◽  
Epithelial Tubes

Cell-generated mechanical forces drive many of the tissue movements and rearrangements that are required to transform simple populations of cells into the complex three-dimensional geometries of mature organs. However, mechanical forces do not need to arise from active cellular movements. Recent studies have illuminated the roles of passive forces that result from mechanical instabilities between epithelial tissues and their surroundings. These mechanical instabilities cause essentially one-dimensional epithelial tubes and two-dimensional epithelial sheets to buckle or wrinkle into complex topologies containing loops, folds, and undulations in organs as diverse as the brain, the intestine, and the lung. Here, I highlight examples of buckling and wrinkling morphogenesis, and suggest that this morphogenetic mechanism may be broadly responsible for sculpting organ form.

scholarly journals Modeling of intracranial vessels and Simulation of cerebral blood flow

2020 ◽  
Vol 185 ◽  
pp. 03030
Author(s):  
Yingying Yan ◽  
Li Ke ◽  
Qiang Du ◽  
Xiaodi Ding ◽  
Jia Chen
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Blood Vessels ◽  
Three Dimensional ◽  
Normal Operation ◽  
Automatic Regulation ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Anatomic Structure ◽  
The Brain

The stable regulation of cerebral blood flow plays an important role in the normal operation of brain function. The disturbance of cerebral blood flow automatic regulation will lead to brain injury and lead to cerebrovascular disease. Therefore, it is of practical clinical significance to study the fine modeling of intracranial blood vessels. First of all, based on the anatomic structure of the intracranial blood vessels, the above sagittal sinus vein, sigmoid sinus, superior petrosal sinus, transverse sinus and cerebral arterial circle were mainly modeled, the three-dimensional model of cerebral blood flow is constructed. Secondly, the three-dimensional model is given conductivity characteristics. Through the expansion and contraction of cerebral blood vessels to simulate the self-regulation of cerebral blood flow, the simulation method of cerebral blood flow impedance is studied. When the blood flow changes, the brain impedance is calculated. The simulation data shows that the change trend of the electric potential and the whole brain impedance of the outer layer of the brain is consistent with the theoretical analysis. The experimental results show that the impedance curves and changes calculated by the brain model in this study are consistent with the measured impedance results, which shows that the modeling method in this paper is precise and effective, and provides a theoretical basis for further study of cerebral blood flow problems.

scholarly journals Three-Dimensional Reconstruction of Two-Dimensional Cardiovascular Angiography Image Sequences by Local Threshold Segmentation Algorithm

2022 ◽  
Vol 2022 ◽  
pp. 1-10
Author(s):  
Shenming Yu
Keyword(s):  
Blood Vessel ◽  
Blood Vessels ◽  
Three Dimensional ◽  
Segmentation Algorithm ◽  
Two Dimensional ◽  
Three Dimensional Reconstruction ◽  
Gaussian Smoothing ◽  
Threshold Segmentation ◽  
Local Threshold ◽  
Dimensional Reconstruction

The study focused on the extraction of cardiovascular two-dimensional angiography sequences and the three-dimensional reconstruction based on the local threshold segmentation algorithm. Specifically, the two-dimensional cardiovascular angiography sequence was extracted first, and Gaussian smoothing was adopted for image preprocessing. Then, optimize maximum between-class variance (OSTU) was compared with the traditional two-dimensional OSTU and fast two-dimensional OSTU and applied in the segmentation of cardiovascular angiography images. It was found that the cardiovascular structure itself was continuous, the contrast agent diffused relatively evenly in the blood vessel, and the gray level of the blood vessel was also continuous. The degree of smoothness was consistent in all directions by Gaussian smoothing, avoiding the direction deviation of the smoothened image. The operation time (0.59 s) of the optimize OSTU was significantly shorter than that of traditional OSTU (35.68 s) and fast two-dimensional OSTU (6.34 s) ( P < 0.05 ). The local threshold segmentation algorithm can realize the continuous edge extraction of blood vessels and accurately reflect the stenosis of blood vessels. The results of blood vessel diameter measurement showed that the diameter from the end of blood vessel to the intersection varied linearly from 5.5 mm to 9.0 mm. In short, the optimize OSTU demonstrated good segmentation effects and fast calculation time; it successfully extracted continuous two-dimensional cardiovascular angiography images and can be used in three-dimensional reconstruction of cardiovascular images.

High Resolution Microscopy of Multi-Layered Biological Crystals

1982 ◽  
Vol 40 ◽  
pp. 80-83
Author(s):  
H.A. Cohen ◽  
T.W. Jeng ◽  
W. Chiu
Keyword(s):  
High Resolution ◽  
Low Dose ◽  
Three Dimensional ◽  
Data Interpretation ◽  
Two Dimensional ◽  
Biological Objects ◽  
Density Maps ◽  
Density Map ◽  
Complex Crystal ◽  
High Resolution Microscopy

This tutorial will discuss the methodology of low dose electron diffraction and imaging of crystalline biological objects, the problems of data interpretation for two-dimensional projected density maps of glucose embedded protein crystals, the factors to be considered in combining tilt data from three-dimensional crystals, and finally, the prospects of achieving a high resolution three-dimensional density map of a biological crystal. This methodology will be illustrated using two proteins under investigation in our laboratory, the T4 DNA helix destabilizing protein gp32*I and the crotoxin complex crystal.

Instrumentation For Quantitative Microscopy

1977 ◽  
Vol 35 ◽  
pp. 206-209
Author(s):  
B. Ralph ◽  
A.R. Jones
Keyword(s):  
Volume Fraction ◽  
Three Dimensional ◽  
Two Dimensional ◽  
Automatic Data ◽  
Phase Volume Fraction ◽  
Statistical Confidence ◽  
Resultant Data ◽  
Automatic Data Collection ◽  
Third Dimension ◽  
Evolution Of Microstructure

In all fields of microscopy there is an increasing interest in the quantification of microstructure. This interest may stem from a desire to establish quality control parameters or may have a more fundamental requirement involving the derivation of parameters which partially or completely define the three dimensional nature of the microstructure. This latter categorey of study may arise from an interest in the evolution of microstructure or from a desire to generate detailed property/microstructure relationships. In the more fundamental studies some convolution of two-dimensional data into the third dimension (stereological analysis) will be necessary.In some cases the two-dimensional data may be acquired relatively easily without recourse to automatic data collection and further, it may prove possible to perform the data reduction and analysis relatively easily. In such cases the only recourse to machines may well be in establishing the statistical confidence of the resultant data. Such relatively straightforward studies tend to result from acquiring data on the whole assemblage of features making up the microstructure. In this field data mode, when parameters such as phase volume fraction, mean size etc. are sought, the main case for resorting to automation is in order to perform repetitive analyses since each analysis is relatively easily performed.

A linearity test for thick specimens imaged by HVEM over a 180° angular range

1991 ◽  
Vol 49 ◽  
pp. 552-553
Author(s):  
Yu Liu
Keyword(s):  
Phase Contrast ◽  
Three Dimensional ◽  
Angular Range ◽  
Two Dimensional ◽  
Back Projection ◽  
Line Integral ◽  
Exponential Law ◽  
Transmission Electron ◽  
Absorption Law ◽  
Linearity Test

The image obtained in a transmission electron microscope is the two-dimensional projection of a three-dimensional (3D) object. The 3D reconstruction of the object can be calculated from a series of projections by back-projection, but this algorithm assumes that the image is linearly related to a line integral of the object function. However, there are two kinds of contrast in electron microscopy, scattering and phase contrast, of which only the latter is linear with the optical density (OD) in the micrograph. Therefore the OD can be used as a measure of the projection only for thin specimens where phase contrast dominates the image. For thick specimens, where scattering contrast predominates, an exponential absorption law holds, and a logarithm of OD must be used. However, for large thicknesses, the simple exponential law might break down due to multiple and inelastic scattering.

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