Two Dimensional Laser Scanner for Blood Perfusion Imaging Through Curved Sections of Human Forearm

2015 ◽  
Vol 12 (1) ◽  
pp. 1007-1015
Author(s):  
S. Ambika ◽  
H. Archana
Keyword(s):  
Perfusion Imaging ◽  
Laser Scanner ◽  
Blood Perfusion ◽  
Two Dimensional ◽  
Human Forearm

Dynamic Contrast-Enhanced MRI and Fractal Characteristics of Percolation Clusters in Two-Dimensional Tumor Blood Perfusion

1999 ◽  
Vol 121 (5) ◽  
pp. 480-486 ◽  
Author(s):  
O. I. Craciunescu ◽  
S. K. Das ◽  
S. T. Clegg
Keyword(s):  
Tumor Tissue ◽  
Blood Perfusion ◽  
Percolation Cluster ◽  
Three Dimensions ◽  
Invasion Percolation ◽  
Two Dimensional ◽  
Tumor Perfusion ◽  
Dynamic Contrast Enhanced ◽  
Contrast Enhanced ◽  
Fractal Characteristics

Dynamic contrast-enhanced magnetic resonance imaging (DE-MRI) of the tumor blood pool is used to study tumor tissue perfusion. The results are then analyzed using percolation models. Percolation cluster geometry is depicted using the wash-in component of MRI contrast signal intensity. Fractal characteristics are determined for each two-dimensional cluster. The invasion percolation model is used to describe the evolution of the tumor perfusion front. Although tumor perfusion can be depicted rigorously only in three dimensions, two-dimensional cases are used to validate the methodology. It is concluded that the blood perfusion in a two-dimensional tumor vessel network has a fractal structure and that the evolution of the perfusion front can be characterized using invasion percolation. For all the cases studied, the front starts to grow from the periphery of the tumor (where the feeding vessel was assumed to lie) and continues to grow toward the center of the tumor, accounting for the well-documented perfused periphery and necrotic core of the tumor tissue.

A two-dimensional laser-scanner system for geotechnical processes monitoring

2018 ◽  
pp. 865-870 ◽  
Author(s):  
M.D. Valencia-Galindo ◽  
L.N. Beltrán-Rodriguez ◽  
J.A. Sánchez-Peralta ◽  
J.S. Tituaña-Puente ◽  
M.G. Trujillo-Vela ◽  
...  
Keyword(s):  
Laser Scanner ◽  
Two Dimensional

A Comparative Analysis of Thermal Blood Perfusion Measurement Techniques

1987 ◽  
Vol 109 (3) ◽  
pp. 218-225 ◽  
Author(s):  
R. Kress ◽  
R. Roemer
Keyword(s):  
Blood Flow ◽  
Steady State ◽  
Time Window ◽  
Measurement Techniques ◽  
Temperature Response ◽  
Blood Perfusion ◽  
Analytical Models ◽  
Transient Temperature ◽  
Two Dimensional ◽  
Transient Heating

The object of this study was to devise a unified method for comparing different thermal techniques for the estimation of blood perfusion rates and to perform a comparison for several common techniques. The approach used was to develop analytical models for the temperature response for all combinations of five power deposition geometries (spherical, one- and two-dimensional cylindrical, and one- and two-dimensional Gaussian) and three transient heating techniques (temperature pulse-decay, temperature step function, and constant-power heat-up) plus one steady-state heating technique. The transient models were used to determine the range of times (the time window) when a significant portion of the transient temperature response was due to blood perfusion. This time window was defined to begin when the difference between the conduction-only and the conduction-plus-blood flow transient temperature (or power) responses exceeded a specified value, and to end when the conduction-plus-blood flow transient temperature (or power) reached a specified fraction of its steady-state value. The results are summarized in dimensionless plots showing the size of the time windows for each of the transient perfusion estimation techniques. Several conclusions were drawn, in particular: (a) low perfusions are difficult to estimate because of the dominance of conduction, (b) large heated regions are better suited for estimation of low perfusions, (c) noninvasive heating techniques are superior because they have the potential to minimize conduction effects, and (d) none of the transient techniques appears to be clearly superior to the others.

Thermography as a Means of Blood Perfusion Measurement

1979 ◽  
Vol 101 (4) ◽  
pp. 246-249 ◽  
Author(s):  
J. E. Francis ◽  
R. Roggli ◽  
T. J. Love ◽  
C. P. Robinson
Keyword(s):  
Blood Flow ◽  
Skin Temperature ◽  
Strain Gage ◽  
Infrared Camera ◽  
Blood Perfusion ◽  
The Body ◽  
Perfusion Rate ◽  
Perfusion Measurement ◽  
Blood Perfusion Rate ◽  
Human Forearm

The scanning infrared camera has been used to verify an analytical model relating blood perfusion rate to skin temperature. The blood perfusion rates were measured with both the mercury strain gage and the volume plethysmograph on the human forearm. Thermograms were taken of the forearm and temperature measured using an optical densitometer. Comparison of the volume plethysmograph with the strain gage, and the thermograms with the strain gage indicate thermography to be a useful means of measuring blood flow. Thermography has the advantages of being noninvasive and can be used to measure blood perfusion in parts of the body not easily monitored with occlusive techniques.

Laser Doppler Perfusion Imaging for Assessment of Skin Blood Perfusion After Acupuncture

2008 ◽  
Vol 20 (2) ◽  
pp. 109-118 ◽  
Author(s):  
Wei-bo Zhang ◽  
Ling-ling Wang ◽  
Tao Huang ◽  
Yu-ying Tian ◽  
Yi-hui Xu ◽  
...  
Keyword(s):  
Perfusion Imaging ◽  
Blood Perfusion ◽  
Laser Doppler ◽  
Laser Doppler Perfusion Imaging ◽  
Skin Blood Perfusion

A compact two-dimensional laser scanner based on piezoelectric actuators

2015 ◽  
Vol 86 (1) ◽  
pp. 013102 ◽  
Author(s):  
Chen Wei ◽  
Chen Sihai ◽  
Luo Dong ◽  
Jiao Guohua
Keyword(s):  
Laser Scanner ◽  
Piezoelectric Actuators ◽  
Two Dimensional
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