@article { author = {Ansarinejad, Abdolkazem and Donetti, Marco and Adelaide Garella, Maria and Giordanengo, Simona and Cirio, Roberto and Marchetto, Flavio and Monaco, Vincenzo and Peroni, Cristiana and Sacchi, Roberto}, title = {Preliminary Characterization Tests of Detectors of on-Line Monitor Systems of the Italian National Center of Oncological Hadron-Therapy (CNAO)}, journal = {Iranian Journal of Medical Physics}, volume = {9}, number = {4}, pages = {225-232}, year = {2012}, publisher = {Mashhad University of Medical Sciences}, issn = {2345-3672}, eissn = {2345-3672}, doi = {10.22038/ijmp.2013.464}, abstract = {Introduction Hadron-therapy is an effective technique used to treat tumors that are located between or nearby vital organs. The Italian National Center of Oncological Hadron-therapy (CNAO) has been realized as the first facility in Italy to treat very difficult tumors with protons and Carbon ions. The on-line monitor system for CNAO has been developed by the Department of Physics of the University of Torino and Italian National Institute of Nuclear Physics (INFN). The monitoring system performs the on-line checking of the beam intensity, dimension, and beam position. Materials and Methods The monitor system is based on parallel plate ionization chambers and is composed of five ionization chambers with the anodes fully integrated or segmented in pixels or strips that are placed in two boxes. A series of measurements were performed that involve the background current and the detectors have been characterized by means of a series of preliminary testes in order to verify reproducibility and uniformity of the chambers using an X-ray source. Results The measured background currents for StripX, StripY and Pixel chambers are five orders of magnitude smaller than the nominal treatment current. The reproducibility error of chambers is less than 1%. The analysis of the uniformity showed that the monitor devices have a spread in gain that varies, but only about 2%. Conclusion The reproducibility and the uniformity values are considered as a good result, taking into account that the X-ray energy range is several orders of magnitude smaller than the particle energies used at CNAO.}, keywords = {Active Beam Delivery System,Hadron Therapy,Ionization Chamber,On-Line Detectors}, url = {https://ijmp.mums.ac.ir/article_464.html}, eprint = {https://ijmp.mums.ac.ir/article_464_4885713f2ec1e3f9bd4ef644984632c4.pdf} } @article { author = {Bahreyni Toossi, Mohammad Taghi and Bahrami, Mohammad}, title = {Assessment of Patient Dose from CT Examinations in Khorasan, Iran}, journal = {Iranian Journal of Medical Physics}, volume = {9}, number = {4}, pages = {233-238}, year = {2012}, publisher = {Mashhad University of Medical Sciences}, issn = {2345-3672}, eissn = {2345-3672}, doi = {10.22038/ijmp.2013.465}, abstract = {Introduction Computed Tomography scans are a very important tool for diagnosis and assessment of response to treatment in the practice of medicine. Ionizing radiation in medical imaging is undoubtedly one of the most powerful diagnostic tools in medicine. Yet, as with all medical interventions, there are potential risks in addition to the clear potential benefits. Materials and Methods Two reference dose quantities have been defined in order to promote the use of good technique in CT. These are weighted CT dose index (CTDIw) in (mGy) for a single slice in serial scanning or per rotation in helical scanning, and dose–length product (DLP) per complete examination (mGy.cm), All measurements were performed using a pencil shaped ionization chamber introduced into polymethyl methacrylate cylindrical brain and body phantoms. This survey was performed on 7 CT scanners in Khorasan Province-Iran. Results DLP for brain, chest, abdomen and pelvic examinations had a range of 255 - 1026, 76-1277, 48-737, 69-854 mGy.cm, respectively. Conclusion The results obtained in this study show that the DLP values obtained in this province are lower than European Commission reference dose levels (EC RDL), in other words performance of all the scanners were satisfactory.}, keywords = {DLP,CT,Ionization Chamber}, url = {https://ijmp.mums.ac.ir/article_465.html}, eprint = {https://ijmp.mums.ac.ir/article_465_7dd2b6fb16de1612b04084752cdf967a.pdf} } @article { author = {Changizi, Vahid and Angaji, Mina and Zare, Mohammad Reza and Abbasnejad, Khatoon}, title = {Evaluation of 226Ra, 232Th, 137Cs and 40K “Agaricus Bisporus” Activity in Cultivated Edible Mushroom formed in Tehran Province- Iran}, journal = {Iranian Journal of Medical Physics}, volume = {9}, number = {4}, pages = {239-244}, year = {2012}, publisher = {Mashhad University of Medical Sciences}, issn = {2345-3672}, eissn = {2345-3672}, doi = {10.22038/ijmp.2013.466}, abstract = {Introduction Natural and man made radioactive sources exist in our environment they can enter into our food chains. One of these is the soil-mushroom-human chain. High level doses of natural radiation can cause hazards to humans. Materials and Methods Samples of Agaricus bisporus cultivated edible mushroom in Tehran province- Iran were collected from 7 farms. Specific activity of 226Ra, 228Ra, 137Cs, 40K and 235U of the samples were measured by two HPGe detectors. Results Specific activity of 226Ra, 228Ra, 137Cs and 40K in the edible mushroom samples were equal to 0.06 ± 0.03 - 0.7 ± 0.2 Bq kg-1 dry, 1.4 ± 0.7 Bq kg-1 dry, 0.1 ± 0.03- 0.3 ± 0.1 Bq kg-1dry and 920 ± 400 - 1370 ± 900 Bq kg-1dry , respectively. Conclusion As the measured concentrations of the radionuclides of interest are close or lower than MDA (Minimum Detectable Activity). Consumption of the mushrooms would impose no health consequences to the consumers.}, keywords = {Edible Mushroom,Agaricus Bisporus,HPGe Detector,Tehran Province,Radionuclides}, url = {https://ijmp.mums.ac.ir/article_466.html}, eprint = {https://ijmp.mums.ac.ir/article_466_02c3903b68dce19e56357de2a70eff04.pdf} } @article { author = {U. Esen, Nsikan and Obed, Rachel. I.}, title = {Doses Received by Patients during Thorax X-Ray Examinations}, journal = {Iranian Journal of Medical Physics}, volume = {9}, number = {4}, pages = {245-251}, year = {2012}, publisher = {Mashhad University of Medical Sciences}, issn = {2345-3672}, eissn = {2345-3672}, doi = {10.22038/ijmp.2013.467}, abstract = {Introduction Radiation exposures from diagnostic medical examinations are generally low and are almost always justified by the benefits of accurate diagnosis of possible disease conditions. Therefore, entrance skin dose (ESD), body organ dose (BOD), and effective dose (ED) from adult patients undergoing routine thorax posterior-anterior (PA) and thorax right lateral (RLAT) were estimated in University Hospital, Port Harcourt, Southern Nigeria. Materials and Methods Totally, 102 patients were considered in this work. Using software packages to carry out ESD, BOD, and ED is a recent resource in dosimetry and is being widely used in hospitals. The software used in this work was  CALDose_X 5.0. The software makes use of the technical exposure parameters and the tube output of the X-ray machine. Results The estimated ESD median values were 0.96 and 1.85 mGy for thorax posterior anterior (PA) and right lateral (RLAT), respectively. The highest BOD was in the adrenals (270 µGy) for thorax PA and Liver (263 µGy) for thorax RLAT. Similarly, ED for thorax PA and RLAT examination were 0.068 and 0.107 mGy, respectively. Conclusion It could be observed that examinations that imparted the highest ESD were thorax PA when compared with the established dose level. Therefore, these results call for quality assurance program (QAP) in diagnostic X-ray units in Nigeria hospitals.}, keywords = {Entrance Skin Dose,Effective Dose,Radiography}, url = {https://ijmp.mums.ac.ir/article_467.html}, eprint = {https://ijmp.mums.ac.ir/article_467_137e4bc823b4cc679dc52b02f188e214.pdf} } @article { author = {Etrati Khosroshahi, Mohammad and Ghazanfari, Lida and Hasan-nejad, Zahra}, title = {Preliminary Results of Treating Cancerous Cells of Lung (QU-DB) by Hyperthermia using Diode Laser and Gold Coated Fe3O4/SiO2 Nano-Shells: An in-Vitro Assay}, journal = {Iranian Journal of Medical Physics}, volume = {9}, number = {4}, pages = {253-263}, year = {2012}, publisher = {Mashhad University of Medical Sciences}, issn = {2345-3672}, eissn = {2345-3672}, doi = {10.22038/ijmp.2013.469}, abstract = {Introduction In this study, we describe the results of controlled synthesis and application of gold coated Fe3O4/SiO2 nano-shells combined with the optical property of gold for enhancement of selective photothermal interaction with cancerous cells based on the surface plasmon resonance (SPR) Phenomena. Materials and Methods Magnetite Nano-Particles (MNPs) were prepared by means of co-precipitation. MNPs were modified with a thin layer of Silica using the Stober method. The amino-modified Fe3O4/SiO2 nano-shells were covered with gold colloids as a self-assembeled process. In-vitro assays were performed to determine the effect of apoptosis of the cells based on the cells morphological changes. Results The biologically inert nano-shells (85 nm) with a Magnetite/Silica core and a gold shell were optically activated. A successful laser-hyperthermia based on the thermal effect of surface plasmon resonance was performed using different gold concentrations. The thermal profile effects of laser power are presented as ideal cases of nanoshell-assisted photo-thermal therapy. The thermally-induced cell death has been shown to be dependent on NPs concentration and laser power density. The power densities of 157 and 184 W/cm2 caused complete cell death at the focal point of the laser beam.Cell damage was reduced by decreasing the power density of laser. Also, a larger area of damage on cell culture plates was observed at longer intervals of laser irradiation. Conclusion An optimized laser-(SPR) hyperthermia was obtained using a concentration of gold coated Fe3O4/SiO2 nano-shells concentration=0.1 mg/ml at intensity=157 W/cm2 at 60s.}, keywords = {Diode laser,Hyperthermia,Lung Cancerous Cell,Metallic Nano-Shells,Surface Plasmon Resonance}, url = {https://ijmp.mums.ac.ir/article_469.html}, eprint = {https://ijmp.mums.ac.ir/article_469_24aa12e410071bfae5cc84946e53f35b.pdf} } @article { author = {Ghayoumi zadeh, Hossein and Haddadnia, Javad and Hashemian, Maryam and Hassanpour, Kazem}, title = {Diagnosis of Breast Cancer using a Combination of Genetic Algorithm and Artificial Neural Network in Medical Infrared Thermal Imaging}, journal = {Iranian Journal of Medical Physics}, volume = {9}, number = {4}, pages = {265-274}, year = {2012}, publisher = {Mashhad University of Medical Sciences}, issn = {2345-3672}, eissn = {2345-3672}, doi = {10.22038/ijmp.2013.470}, abstract = {Introduction This study is an effort to diagnose breast cancer by processing the quantitative and qualitative information obtained from medical infrared imaging. The medical infrared imaging is free from any harmful radiation and it is one of the best advantages of the proposed method. By analyzing this information, the best diagnostic parameters among the available parameters are selected and its sensitivity and precision in cancer diagnosis is improved by utilizing genetic algorithm and artificial neural network. Materials and Methods In this research, the necessary information is obtained from thermal imaging of 200 people, and 8 diagnostic parameters are extracted from these images by the research team. Then these 8 parameters are used as input of our proposed combinatorial model which is formed using artificial neural network and genetic algorithm. Results Our results have revealed that comparison of the breast areas; thermal pattern and kurtosis are the most important parameters in breast cancer diagnosis from proposed medical infrared imaging. The proposed combinatorial model with a 50% sensitivity, 75% specificity and, 70% accuracy shows good precision in cancer diagnosis. Conclusion The main goal of this article is to describe the capability of infrared imaging in preliminary diagnosis of breast cancer. This method is beneficial to patients with and without symptoms. The results indicate that the proposed combinatorial model produces optimum and efficacious parameters in comparison to other parameters and can improve the capability and power of globalizing the artificial neural network. This will help physicians in more accurate diagnosis of this type of cancer.  }, keywords = {Artificial neural network,Breast Cancer,Genetic Algorithm,Thermography}, url = {https://ijmp.mums.ac.ir/article_470.html}, eprint = {https://ijmp.mums.ac.ir/article_470_506d6c77e0ebff4fd5ece319576d59a3.pdf} } @article { author = {karami, Golestan and Oghabian, Mohammad Ali and Faeghi, Fariborz and Tohidnia, Mohammad Rasoul}, title = {Effect of Phase-Encoding Reduction on Geometric Distortion and BOLD Signal Changes in fMRI}, journal = {Iranian Journal of Medical Physics}, volume = {9}, number = {4}, pages = {275-281}, year = {2012}, publisher = {Mashhad University of Medical Sciences}, issn = {2345-3672}, eissn = {2345-3672}, doi = {10.22038/ijmp.2013.473}, abstract = {Introduction Echo-planar imaging (EPI) is a group of fast data acquisition methods commonly used in fMRI studies. It acquires multiple image lines in k-space after a single excitation, which leads to a very short scan time. A well-known problem with EPI is that it is more sensitive to distortions due to the used encoding scheme. Source of distortion is inhomogeneity in the static B0 field that causes more geometric distortion in phase encoding direction. This inhomogeneity is induced mainly by the magnetic susceptibility differences between various structures within the object placed inside the scanner, often at air-tissue or bone-tissue interfaces. Methods of reducing EPI distortion are mainly based on decreasing steps of the phase encoding. Reducing steps of phase encoding can be applied by reducing field of view, slice thickness, and/or the use of parallel acquisition technique. Materials and Methods We obtained three data acquisitions with different FOVs including: conventional low resolution, conventional high resolution, and zoomed high resolution EPIs. Moreover we used SENSE technique for phase encoding reduction. All experiments were carried out on three Tesla scanners (Siemens, TIM, and Germany) equipped with 12 channel head coil. Ten subjects participated in the experiments. Results The data were processed by FSL software and were evaluated by ANOVA. Distortion was assessed by obtaining low displacement voxels map, and calculated from a field map image. Conclusion We showed that image distortion can be reduced by decreasing slice thickness and phase encoding steps. Distortion reduction in zoomed technique resulted the lowest level, but at the cost of signal-to-noise loss. Moreover, the SENSE technique was shown to decrease the amount of image distortion, efficiently.}, keywords = {fMRI,EPI,Echo Planar Imaging,BOLD Signal,Geometric Distortion}, url = {https://ijmp.mums.ac.ir/article_473.html}, eprint = {https://ijmp.mums.ac.ir/article_473_9c615fed20c59ff1d2bb6bc59b519005.pdf} } @article { author = {Shojaedini, Seyed Vahab and Kermani, Ali and Nafisi, Vahid Reza}, title = {A New Method for Sperm Detection in Human Semen: Combination of Hypothesis Testing and Local Mapping of Wavelet Sub-Bands}, journal = {Iranian Journal of Medical Physics}, volume = {9}, number = {4}, pages = {283-292}, year = {2012}, publisher = {Mashhad University of Medical Sciences}, issn = {2345-3672}, eissn = {2345-3672}, doi = {10.22038/ijmp.2013.474}, abstract = {Introduction Automated methods for sperm characterization in microscopic videos have some limitations such as: low contrast of the video frames and possibility of neighboring sperms to touch each other. In this paper a new method is introduced for detection of sperms in microscopic videos. Materials and Methods In this work, first microscopic videos are captured from specimens of human semen. Several frames of these videos are transformed to wavelet sub-bands and bit-related planes are constructed from wavelet sub-bands separately. Finally, the acquired bit planes are mapped by different local mapping functions and decision is made using continuity and discontinuity of the mapping results. Based on the above decision procedure, each region of the microscopic image is assigned to either a sperm or other parts of semen. Results Performance of the proposed method was evaluated by two sets of microscopic videos which have been captured from semen of some infertile men. The first sets belonged to semen specimens with low densities of sperms and the second set belonged to semen specimens with high densities of sperms. Conclusion The results of this study revealed that the proposed method in this work is more efficient in sperm detection and extraction compared with the current approaches in both scenarios. Furthermore, it is evident that for specimens with higher sperm densities the proposed method improved sperm detection also reduces false detection rate considerably.}, keywords = {Detection,Hypothesis Testing,Mapping,Microscopic Video,Semen,Wavelet Sub-Bands}, url = {https://ijmp.mums.ac.ir/article_474.html}, eprint = {https://ijmp.mums.ac.ir/article_474_7102290b2e85111372780fde2887576a.pdf} }