The aim of this study was to evaluate the physical properties of epoxy resin to be used as a phantom material to mimic the liver of human body in computed tomography (CT) protocols. The epoxy resin type of E-110I/H-9 was mixed uniformly with a ratio 2:1 of resin and hardener. The mass density, effective atomic number, linear and mass attenuation coefficients of the epoxy were calculated. The linear and mass attenuation coefficients were calculated at relevant CT photon energy 40-65keV using the FFAST database (NIST, USA). Then, the calculated measurements of fabricated epoxy were compared with the standard values of human liver. The results indicated that the mass density and effective atomic number had achieved good agreement with the liver values. The theoretical values of linear and mass attenuation coefficients were in strong agreement with the values reported in International Commission on Radiation Units and Measurements. Therefore, the results physically verify the suitability of epoxy resin E-110I/H-9 as a CT phantom material to mimic the human liver.

This study aims to evaluate the attenuation properties of epoxy resin and Rhizophora spp. particleboards bonded with epoxy resin as tissue equivalent phantom materials. The calculated linear and mass attenuation coefficients of epoxy resin and Rhizophora spp. particleboards bonded with three different weight percentages of the epoxy resin (5%, 10% and 15%) were compared with theoretical (XCOM) and experimental measurements of human liver tissue and water at the same energy levels. The 241Am and 109Cd point sources were used to measure the linear and mass attenuation coefficients of the samples at gamma energies; 26.3, 59.5 and 88.0 keV. The computed tomography (CT) scanner was employed to determine the mean attenuation values (CT number) for the fabricated samples and water at CT tube energy 120 kVp. The linear and mass attenuation coefficients of epoxy resin and fabricated Rhizophora spp. particleboard bonded with 15% of epoxy resin provided excellent agreement to the values of XCOM calculated in the human liver tissue and water, respectively. The CT number results showed that the epoxy resin and the Rhizophora spp. particleboard bonded with15% epoxy were in a good agreement with those of human liver tissue and water, respectively. Therefore, the overall attenuation measurements of this study verify the applicability of epoxy resin as a phantom material to mimic the human liver in CT examinations and the epoxy–Rhizophora spp. particleboard fabricated with 15% epoxy resin can be used as a tissue equivalent material corresponding to CT energy range.

Computed tomography (CT) employs X-ray radiation to create cross-sectional images. Dual-energy CT acquisition includes the images acquired from an alternating voltage of X-ray tube: a low- and a high-peak kilovoltage. The main objective of this study is to determine the best slice thickness that reduces image noise with adequate diagnostic information using dual energy CT head protocol. The study used the ImageJ software and statistical analyses to aid the medical image analysis of dual-energy CT. In this study, ImageJ software and F-test were utilised as the combination methods to analyse DICOM CT images. They were used to investigate the effect of slice thickness on noise and visibility in dual-energy CT head protocol images. Catphan- 600 phantom was scanned at different slice thickness values; .6, 1, 2,3,4,5 and 6 mm, then quantitative analyses were carried out. The DECT operated in helical mode with another fixed scan parameter values. Based on F-test statistical analyses, image noise at 0.6, 1, and 2 mm were significantly different compared to the other images acquired at slice thickness of 3, 4, 5, and 6 mm. However, no significant differences of image noise were observed at 3, 4, 5, and 6 mm. As a result, better diagnostic image value, image visibility, and lower image noise in dual-energy CT head protocol was observed at a slice thickness of 3 mm.

Background: Doppler technique is a technology that can raise the predictive, diagnostic, and monitoring abilities in blood flow and suitable for researchers. The application depends on Doppler shift (shift frequencies), wherein the movement of red blood cells away from the probe is determined by the decrease or increase in the ultrasound (US) frequency. Methods: In this experiment, the clinical US (Hitachi Avious [HI] model) system was used as a primary instrument for data acquisition and test the compatibility, efficacy, and validation of artificial blood (blood-mimicking fluid [BMF]) by color- and motion-mode. This BMF was prepared for use in the Doppler flow phantom. Results: The motion of BMF through the vessel-mimicking material (VMM) was parallel and the flow was laminar and in the straight form (regular flow of BMF inside the VMM). Moreover, the scale of color velocity in the normal range at that flow rate was in the normal range. Conclusion: The new BMF that is being valid and effective in utilizing for US in vitro research applications. In addition, the clinical US ([HI] model) system can be used as a suitable instrument for data acquisition and test the compatibility, efficacy, and validation at in vitro applications (BMF, flow phantom components).

A Doppler ultrasound is a noninvasive test that can be used to estimate the blood flow through the vessels. Presently, few flow phantoms are being used to be qualified for long-term utilize and storage with high physiological flow rate Doppler ultrasound. The main drawback of the two hydrogel materials items (Konjac (K) and carrageenan (C) (KC)) that it is not fit for long-term storage and easy to deteriorate. Thus, this research study focuses on the characterization and construction of a robust and elastic wall-less flow phantom with suitable acoustical properties of TMM. The mechanisms for the fabrication of a wall-less flow phantom utilizing a physically strong material such as K, C, and gelatin (bovine skin)-based TMM were explained. In addition, the clinical ultrasound (Hitachi Avius (HI)) system was used as the main instrument for data acquisition. Vessel mimicking material (VMM) with dimensions of 15.0 mm depth equal to those of human common carotid arteries (CCA) were obtained with pulsatile flow. The acoustical properties (speed of sound and attenuation were 1533±2 m/s and 0.2 dB/cm. MHz, respectively) of a new TMM were agreed with the IEC 61685 standards. Furthermore, the velocity percentages error were decreased with increase in the Doppler angle (the lowest % error (3%) it was at 53◦). The gelatin from bovine skin was a proper material to be added to KC to enhance the strength of TMM during for long-term utilize and storage of high-flow of blood mimicking Fluid (BMF). This wall-less flow phantom will be a suitable instrument for examining in-vitro research studies.

The aim of this study was to evaluate the physical properties of epoxy resin to be used as a phantom material to mimic the liver of human body in computed tomography (CT) protocols. The epoxy resin type of E-110I/H-9 was mixed uniformly with a ratio 2:1 of resin and hardener. The mass density, effective atomic number, linear and mass attenuation coefficients of the epoxy were calculated. The linear and mass attenuation coefficients were calculated at relevant CT photon energy 40-65keV using the FFAST database (NIST, USA). Then, the calculated measurements of fabricated epoxy were compared with the standard values of human liver. The results indicated that the mass density and effective atomic number had achieved good agreement with the liver values. The theoretical values of linear and mass attenuation coefficients were in strong agreement with the values reported in International Commission on Radiation Units and Measurements. Therefore, the results physically verify the suitability of epoxy resin E-110I/H-9 as a CT phantom material to mimic the human liver.

Computed tomography (CT) employs X-ray radiation to generate cross-sectional images. This article is concerning the ImageJ software and statistical analysis to aid CT image analysis. In this particular study, the ImageJ software and the Independent t-test were used as the combined methods to analyze the beam hardening artifact and image noise in dual energy images compared to the images acquired in single energy CT. High attenuation material (gypsum) had inserted in the peripheral holes of CT dose index phantom. The phantom was scanned using routine head protocol parameters for both single and dual energy CT. The quantitative analyses were carried out using the Image J software and Independent t-test. The results showed that the beam hardening artifact (p

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الكلمات المفتاحية

Beam Hardening Artifact, Computed Tomography, Statistical Analysis