نتایج جستجو برای: tissue equivalent phantom
تعداد نتایج: 1059439 فیلتر نتایج به سال:
Background and purpose: Dual-energy mammography technique is used for improving the accuracy of breast cancer diagnosis especially in dense breast cases and also detection of micro-calcifications which are early signs of breast cancer. The purpose of this study was to investigate the automatic separation feasibility of micro-calcification images in breast tissue images and evaluating its accura...
Introduction After the publication of Task Group number 43 dose calculation formalism by the American Association of Physicists in Medicine (AAPM), this method has been known as the most common dose calculation method in brachytherapy treatment planning. In this formalism, the water phantom is introduced as the reference dosimetry phantom, while the attenuation coefficient of the sources in the...
Background: For radiotherapy of total skin including sub-cutaneous tissue up to a depth of 3 cm on the entire left leg of an adult (Angiosarcoma skin), a complex treatment with multiple stationary electron fields was planned at our clinic. The details of dosimetry, clinical dose measurements are presented. Materials and Methods: The treatment planned with 6 overlapping 9 MeV electron fields in ...
The physical basis for the measurement of Hp(10) and H*(10) in mixed high-energy electron and photon fields was developed for the general case of non-existing secondary charged particle equilibrium at the reference depth of 10 mm. Several mixed fields, with different electron fluence distributions were produced and the corresponding depth ionisation curves were measured in a Makrolon phantom. B...
Penetration and estimation of absorbed dose of electron in soft tissue is investigated in this paper. Neck phantom was simulated by MCNPX code version 2.6. The Phantom was included skin, adipose, neck tissue, neck bone and thyroid glands. Radiation source kept near to the skin surface and located in the back of the neck. Electrons were collided perpendicular to the skin surface. The curves show...
Background: The aim of this work was to establish how well gel dosimeters performed, as substitutes for brain tissue compared with standard phantom materials such as water, polymethyl-methacrylate (or PMMA), A150 plastic and TE- liquid phantom material for dosimetry of neutron beams in boron neutron capture therapy. Materials and Methods: Thermal neutron fluence, photon dose and epithermal neu...
We have begun clinical trials of optical tomography of the neonatal brain. To validate this research, we have built and imaged an anatomically realistic, tissue-equivalent neonatal head phantom that is hollow, allowing contrasting objects to be placed inside it. Images were reconstructed by use of two finite-element meshes, one generated from a computed tomography image of the phantom and the o...
Microcalcification is one of the earliest and main indicators of breast cancer. Because dual-energy digital mammography could suppress the contrast between the adipose and glandular tissues of the breast, it is considered a promising technique that will improve the detection of microcalcification. In dual-energy digital mammography, the imaged object is a human breast, while in calibration meas...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید