Using Voxel Count Measurements Based On X-Ray Attenuation Coefficient Principle to Estimate Organ Volume during CT Scan

2017 ◽  
pp. 653-659
Author(s):  
Issahaku Shirazu ◽  
Y. B Mensah ◽  
Cyril Schandorf ◽  
S. Y. Mensah
Keyword(s):  
Attenuation Coefficient ◽  
The Body ◽  
Linear Attenuation Coefficient ◽  
X Rays ◽  
Simple Method ◽  
Attenuation Coefficients ◽  
X Ray ◽  
Organ Volume ◽  
Count Method ◽  
Body Tissues

The study provided a simple method of using voxel count method to estimate organ volume together with x-ray attenuation coefficient principle. The aim is to discuss the role of x-ray attenuation coefficient in CT organ volume measurements using voxel count method. The method involve using the principle of linear attenuation coefficient which describes the fraction of a beam of x-rays or gamma rays that is absorbed or scattered per unit thickness of the absorber to enable tissue differentiation and hence the used of volume elements method, where the body is literally divided into 3-dimensional rectangular boxes with known size and thickness. This value basically accounts for the number of atoms within a specified distance of a material and the probability of a photon being scattered or absorbed from the nucleus or an electron of one of these atoms. A graph of linear attenuation coefficients versus radiation energy are used to separate between various body tissues. At a specific energy the difference in attenuation between two tissues is greatest at a specific radiographic contrast in an image. Hence, this variation enable a separation and subsequent measurements of varied tissues. Therefore, it is extremely useful to determine various linear attenuation coefficients of tissues to enable various variations to be determine for clinical application.

scholarly journals X-ray Shielding, Mechanical, Physical, and Water Absorption Properties of Wood/PVC Composites Containing Bismuth Oxide

Polymers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 2212
Author(s):  
Worawat Poltabtim ◽  
Ekachai Wimolmala ◽  
Teerasak Markpin ◽  
Narongrit Sombatsompop ◽  
Vichai Rosarpitak ◽  
...  
Keyword(s):  
Impact Strength ◽  
Water Absorption ◽  
Attenuation Coefficient ◽  
Bismuth Oxide ◽  
Morphological Properties ◽  
Linear Attenuation Coefficient ◽  
X Rays ◽  
Equivalent Thickness ◽  
X Ray ◽  
The Impact

The potential utilization of wood/polyvinyl chloride (WPVC) composites containing an X-ray protective filler, namely bismuth oxide (Bi2O3) particles, was investigated as novel, safe, and environmentally friendly X-ray shielding materials. The wood and Bi2O3 contents used in this work varied from 20 to 40 parts per hundred parts of PVC by weight (pph) and from 0 to 25, 50, 75, and 100 pph, respectively. The study considered X-ray shielding, mechanical, density, water absorption, and morphological properties. The results showed that the overall X-ray shielding parameters, namely the linear attenuation coefficient (µ), mass attenuation coefficient (µm), and lead equivalent thickness (Pbeq), of the WPVC composites increased with increasing Bi2O3 contents but slightly decreased at higher wood contents (40 pph). Furthermore, comparative Pbeq values between the wood/PVC composites and similar commercial X-ray shielding boards indicated that the recommended Bi2O3 contents for the 20 pph (40 ph) wood/PVC composites were 35, 85, and 40 pph (40, 100, and 45 pph) for the attenuation of 60, 100, and 150-kV X-rays, respectively. In addition, the increased Bi2O3 contents in the WPVC composites enhanced the Izod impact strength, hardness (Shore D), and density, but reduced water absorption. On the other hand, the increased wood contents increased the impact strength, hardness (Shore D), and water absorption but lowered the density of the composites. The overall results suggested that the developed WPVC composites had great potential to be used as effective X-ray shielding materials with Bi2O3 acting as a suitable X-ray protective filler.

Quantification of the void content of composite materials using soft X-ray transmittance

2016 ◽  
Vol 30 (11) ◽  
pp. 1522-1540 ◽  
Author(s):  
Takahiro Hayashi ◽  
Takayuki Kobayashi ◽  
Jun Takahashi
Keyword(s):  
Composite Materials ◽  
Attenuation Coefficient ◽  
Mass Production ◽  
Void Content ◽  
X Rays ◽  
Attenuation Coefficients ◽  
X Ray ◽  
Hydrostatic Weighing ◽  
The Difference ◽  
Reinforced Thermoplastics

Carbon fiber reinforced thermoplastics (CFRTPs) have high potential in high-cycle (1 min) molding as a weight-reducing material for the mass production of automobile components. However, residual voids in CFRTPs lead to diminished and unstable mechanical properties; therefore, the effective quantification of the void content in CFRTP products is necessary for developing an affordable system for mass production. In a previous study, we demonstrated that the X-ray attenuation coefficient decreases with increasing void content; thus, measurements of X-ray attenuation coefficients can be used to estimate the void contents of CFRTPs. In this study, we first investigated in detail the soft X-ray attenuation coefficients of completely impregnated composite materials with three different thicknesses; we observed that the attenuation coefficients decreased with increasing composite thickness, even though they should be independent of the thickness according to the Beer–Lambert law. We next demonstrated that although no correlation exists between the X-ray transmittance and the apparent attenuation coefficient of six composites with various void contents, the true attenuation coefficient modified to account for void content exhibits a good linear relationship with the X-ray transmittance, same as fully impregnated composites. Using the approximation line between the X-ray transmittance and the modified attenuation coefficient of CFRTP, we estimated the void content on the basis of the difference between the apparent and true X-ray attenuation coefficients. The average difference in void content determined by conventional hydrostatic weighing and that determined by the proposed X-ray transmittance method was 0.43%. We therefore concluded that the void content of CFRTPs of any thickness can be estimated nondestructively using soft X-rays.

scholarly journals A Mineral X-ray Linear Attenuation Coefficient Tool (MXLAC) to Assess Mineralogical Differentiation for X-ray Computed Tomography Scanning

Minerals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 441
Author(s):  
Lunga Bam ◽  
Jodie Miller ◽  
Megan Becker
Keyword(s):  
Computed Tomography ◽  
Attenuation Coefficient ◽  
Data Bank ◽  
Linear Attenuation Coefficient ◽  
Chemical Formula ◽  
Attenuation Coefficients ◽  
X Ray ◽  
Computed Tomography Scanning ◽  
X Ray Computed ◽  
Tomography Scanning

X-ray computed tomography (XCT) is becoming one of the most important techniques in the geosciences. The technique relies on linear attenuation coefficient differences in order to reveal the internal structure of the rocks. In this work, we present a new excel macro tool, called MXLAC, which is a data bank with an excel interface that uses density, X-ray energy and the mineral chemical formula to allow users to calculate mineral linear attenuation coefficients that can then be used to determine discrimination between mineral pairs. Elements within a mineral and specified by the chemical formula, determine how the X-ray beam is attenuated. Analysis of a variety of scanned mineral pairs with similar densities and attenuation coefficients indicates that an attenuation coefficient difference of greater than or equal to 6% at 45.5 keV effective X-ray energy is required for effective discrimination between two minerals using XCT with single energy scanning. This means that mineral pairs, such as quartz and pyrophyllite cannot be discriminated using the current XCT instruments due to the fact that the attenuation coefficient difference is less than 1.9% at 45.5 keV effective X-ray energy. Garnets and a variety of other minerals were used as examples to illustrate the importance of knowing the actual chemical formula of the mineral to demonstrate whether they can be partially or fully discriminated from each other.

scholarly journals Study the effect of addition Rockwool fibers on the Shielding Radiation  for the X-ray of Low Density Polyethylene (LDPE): دراسة تأثير إضافة ألياف الصوف الصخري على الحجب الإشعاعي للأشعة السينية للبولي اثيلين واطىئ الكثافة

2020 ◽  
Vol 4 (2) ◽  
Author(s):  
Shaymaa H. Jasim, Wisam A. Radhi, Riyadh M. Ramadhan, Raed M
Keyword(s):  
Free Path ◽  
Attenuation Coefficient ◽  
Mean Free Path ◽  
Weight Percent ◽  
Linear Attenuation Coefficient ◽  
X Rays ◽  
X Ray ◽  
Minimum Value ◽  
Maximum Value ◽  
The Mean

The extinction of X-rays (radiation attenuation) was studied using the low-density samples of polyethylene polymer to which the rockwool fibers powder is added as filled filler. This latter was blended with (weight percent) and with a micro-filler (filler particle) the sizes equal to or less than<212 μm. Furthermore, the free path average and linear attenuation coefficient were calculated.  Experimental results showed that the rockwool fibers powder act to reduce the spaces between polymer chains particularly when the weight percent is more than (10%), which implies the capability of the polymer/filler to make, the X-rays applied to the samples; disappear at these rates used in this study. The experimental work was conducted by applying a radiation beam having an energy of 30 kV based on the use of the X-ray unit with two tubes which are; X-ray generating tube and G-M detector with an energy of VG.M =600. The magnitudes of the mean free path are inversely proportional to the weight percent of the compound material whereas the proportionality of these percentages which are particularly the high ones which occur at experimental values of the linear attenuation coefficient. The value of the mean free path of 1.28 cm is the maximum value obtained at a weight percent of 1 %, whereas the minimum value of the mean path was 0.877 cm at a weight percent of 10 %. In addition, the maximum value of the attenuation coefficient obtained is 4.754 cm-1 at a weight percent of 10% and its minimum value at a weight percent of 1% was 0.7 cm-1. The maximum value of transmittance and the minimum value of absorbance were obtained at a weight percent of 10%, are (31.8) and (68.2) respectively. Through the practical results that we obtained that are better suited to high percentages more additive proportions can be used than the percentages used in this research to shielding X-rays more.

Study on gamma ray shielding performance of concretes doped with natural sepiolite mineral

2018 ◽  
Vol 106 (12) ◽  
pp. 1009-1016 ◽  
Author(s):  
Osman Agar
Keyword(s):  
Attenuation Coefficient ◽  
Gamma Ray ◽  
Morphological Structure ◽  
Mean Free Path ◽  
Mass Attenuation Coefficient ◽  
Linear Attenuation Coefficient ◽  
Attenuation Coefficients ◽  
X Ray ◽  
Edx Analyses ◽  
Gamma Ray Attenuation

Abstract Gamma ray attenuation coefficients for various concrete types containing natural sepiolite mineral and B4C have been experimentally investigated at different gamma energies. In order to obtain the gamma rays, the four radioactive point-isotropic sources 133Ba, 137Cs, 60Co and 22Na which energies ranged from 80.9 to 1332.5 keV have been utilized. The measurements have been carried out by using HPGe detector and MCA equipped with a personal computer. The morphological structure and elemental compositions of the concretes have been measured with scanning electron microscope (SEM) and energy-dispersive X-ray (EDX) analyses. Linear attenuation coefficient (μ), mass attenuation coefficient (μm), half value layer (HVL) and mean free path (MFP) have been calculated for all concretes. The obtained results have been compared to the other materials such as Pb and Al.

scholarly journals Determination of the mass attenuation coefficient for Aluminum element using (Cu,Mo) X-rays tubes

2019 ◽  
Vol 24 (1) ◽  
pp. 82
Author(s):  
Ahmad Mohamed Kheder ◽  
Muhsin Hasan Ali
Keyword(s):  
Experimental Data ◽  
Attenuation Coefficient ◽  
Cross Sections ◽  
Mass Attenuation Coefficient ◽  
X Rays ◽  
Attenuation Coefficients ◽  
X Ray ◽  
Mass Attenuation Coefficients ◽  
Mass Attenuation

In this study the value of linear  and mass  attenuation coefficients of Aluminum element (Al) were determinated by using x-ray Cu-tube of energies CuKα (8.048) KeV, CuKβ (8.906) KeV, and Mo-tube of energies MoKα (17.480) KeV and MoKβ (19.609) KeV.the voltage between the two electrodes are up to 35 KV.The measured  values are compared with other experimental data showing a general agreement within a precision of 0.2% - 0.8%. The mass attenuation cross-sections were thus derived and compared with other experimental data available on database of x-ray attenuation cross-sections. The agreement is always within ±7%.   http://dx.doi.org/10.25130/tjps.24.2019.013

X-ray micro tomography in the scanning electron microscope

1978 ◽  
Vol 36 (1) ◽  
pp. 106-107 ◽  
Author(s):  
W. Brünger
Keyword(s):  
Electron Beam ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Target Surface ◽  
The Body ◽  
X Rays ◽  
Cross Sectional ◽  
X Ray ◽  
Micro Tomography ◽  
Scanning Electron

Reconstructive tomography is a new technique in diagnostic radiology for imaging cross-sectional planes of the human body /1/. A collimated beam of X-rays is scanned through a thin slice of the body and the transmitted intensity is recorded by a detector giving a linear shadow graph or projection (see fig. 1). Many of these projections at different angles are used to reconstruct the body-layer, usually with the aid of a computer. The picture element size of present tomographic scanners is approximately 1.1 mm2.Micro tomography can be realized using the very fine X-ray source generated by the focused electron beam of a scanning electron microscope (see fig. 2). The translation of the X-ray source is done by a line scan of the electron beam on a polished target surface /2/. Projections at different angles are produced by rotating the object.During the registration of a single scan the electron beam is deflected in one direction only, while both deflections are operating in the display tube.

Synthesis of Y2O3: Eu Luminescent Phosphor with Increased Dispersion for Use in Medical Purposes

2021 ◽  
Vol 1040 ◽  
pp. 61-67
Author(s):  
Anna B. Vlasenko ◽  
Vadim V. Bakhmetyev ◽  
Sergey V. Mjakin
Keyword(s):  
Particle Size ◽  
Photodynamic Therapy ◽  
Visible Light ◽  
Modern Method ◽  
The Body ◽  
Hydrothermal Processing ◽  
X Ray ◽  
Microwave Annealing ◽  
Body Tissues ◽  
Pyrogenic Silica

Photodynamic therapy (PDT) is a promising modern method for treatment of oncological, bacterial, fungal and viral diseases. However, its application is limited to diseases with superficial localization since the body tissues are not transparent for visible light. To address this problem and extend PDT application to abdominal diseases, an enhanced method of X-ray photodynamic therapy (XRPDT) is suggested, involving X-ray radiation easily penetrating the body tissues. The implementation of this approach requires the development of a pharmacological drug including a photosensitizer stimulated by visible light to yield active oxygen and a nanosized phosphor converting X-ray radiation into visible light with the wavelength required for the photosensitizer activation. This study is aimed at obtaining X-ray stimulated phosphors with nanosized particles suitable for XRPDT application. For this purpose, Y2O3:Eu phosphors were synthesized via hydrothermal processing of the corresponding mixed acetate followed by annealing. To prevent from the undesirable agglomeration of the particles in the course of hydrothermal synthesis and subsequent annealing, different techniques were used, including rapid thermal annealing (RTA), microwave annealing and addition of finely dispersed pyrogenic silica (aerosil) to the phosphor. The microwave annealing was carried out using a special installation including a resonance chamber for maintaining a standing wave of microwave radiation. The performed research allowed the determination of hydrothermal processing optimal duration affording the synthesis of phosphors with the highest luminescence brightness. The application of microwave annealing is found to provide phosphors with a more perfect crystal structure compared with RTA. The developed method of Y2O3:Eu phosphor synthesis involving pyrogenic silica addition to the autoclave allowed the preparation of samples with the amorphous structure and significantly reduced the particle size without a considerable decrease in the luminescence brightness. The particle size of the phosphor synthesized with aerosil addition is less than 100 nm that allows its implementation in pharmacological drugs for XRPDT.

Electron Density and Effective Atomic Number Measurement by Using a Newly Developing Photon Counting CT System

2020 ◽  
Vol 38 ◽  
pp. 93-99
Author(s):  
Hiroshi Sakurai ◽  
Kazushi Hoshi ◽  
Yosuke Harasawa ◽  
Daiki Ono ◽  
Kun Zhang ◽  
...  
Keyword(s):  
Electron Density ◽  
Atomic Number ◽  
Photon Counting ◽  
Effective Atomic Number ◽  
Image Data ◽  
Detector Response ◽  
Simple Method ◽  
Attenuation Coefficients ◽  
X Ray ◽  
Ct System

We developed the photon counting CT system by using a conventional laboratory X-ray source and a CdTe line sensor. Attenuation coefficients were obtained from the measured CT image data. Our suggested method for deriving the electron density and effective atomic number from the measured attenuation coefficients was tested experimentally. The accuracy of the electron densities and effective atomic numbers are about <5 % (the averages of absolute values are 2.6 % and 3.1 %, respectively) for material of 6< Z and Zeff <13. Our suggested simple method, in which we do not need the exact source X-ray spectrum and detector response function, achieves comparable accuracy to the previous reports.

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