Iranian Journal of Medical Physics
Volume:14 Issue: 3, Summer 2017

The great use of electrical appliances in different life applications is one of the most obvious concerns because of its possible health drawbacks. These investigation reports results of electromagnetic field effect emitted from mobile phones on some biophysical parameters of human blood belonging to blood groups A, B, AB & O collected from the normal persons. The parameters observed are surface tension, volume flow rate of blood. This article displays a comparative data of the above parameters for control group and test group.
The blood samples were collected from healthy persons and stored in heparin as anticoagulant. The test samples were exposed with mobile phone up to 1 hour with the interval of 15 min. The parameters such as surface tension and volume flow rate of normal and irradiated blood samples were measured using capillary viscometer, developed at Biophysics Laboratory, Nizam College, Osmania University, Hyderabad, India.
It is interesting to note that surface tension of blood, irrespective of blood group, is increased significantly, when blood exposed to radiation produced by mobile phone. Volume flow rate decreases significantly in A, B and AB blood groups, and increases in blood group O, when blood exposed to radiation produced by mobile phone.
Mobile phone radiation has significant effect on surface tension and volume flow rate of human blood of different blood groups.

Coronary angiography is the most common angiographic procedure for diagnosis and treatment of the heart diseases. Herein, we aimed to evaluate the entrance surface dose (ESD), dose area product (DAP), as well as cancer risk in interventional cardiology procedures.
This study was conducted during July-December 2015 at Shahid Madani Heart Center in Khorramabad, Iran. A total of 225 adult patients including 122 females and 103 males regardless of the risk factors for coronary diseases were participated. Of them, 199 and 26 patients underwent diagnostic coronary angiography (CA) and percutaneous transluminal coronary angioplasty (PTCA), respectively. Each patient underwent CA or PTCA separately. All the procedures were carried out using Siemens angiography system with the pulsed fluoroscopy of 10-30 pulses/s and cine frame rate of 15 frames/s. DAP, ESD, fluoroscopy time (FT), as well as the number of sequences and frames per sequence were collected for each 199 CA and 26 PTCA procedures.
The median values of DAP were 19.77±14.88 and 57.11±33.36 Gy.cm2 in CA and PTCA, respectively. In addition, the median values of ESD were 323.12±245.39 and 1145.22±594.42 mGy in CA and PTCA, respectively. FTs were 114.59±74.33 s in CA and 424.15±292.93 s in PTCA.
The average patient dose and cancer risk estimates in both CA and PTCA were consistent with the reference levels. However, in agreement with other interventional procedures, dose levels in the interventional cardiology are influenced by staff and clinical protocols, as well as the type of equipment.

Irreversible electroporation (IRE) is a process in which the membrane of the cancer cells are irreversibly damaged with the use of high-intensity electric pulses, which in turn leads to cell death. The IRE is a non-thermal way to ablate the cancer cells. This process relies on the distribution of the electric field, which affects the pulse amplitude, width, and electrical conductivity of the tissues. The present study aimed to investigate the relationship of the pulse width and intensity with the conductivity changes during the IRE using simulation.
For the purpose of the study, the COMSOL 5 software was utilized to predict the conductivity changes during the IRE. We used 4,000 bipolar and monopolar pulses with the frequency of 5 kHz and 1 Hz, width of 100 µs, and electric fields of low and high intensity. Subsequently, we built three-dimensional numerical models for the liver tissue.
The results of our study revealed that the conductivity of tissue increased during the application of electrical pulses. Additionally, the conductivity changes increased with the elevation of the electric field intensity.
As the finding of this study indicated, the IRE with high-frequency and low electric field intensity could change the tissue conductivity. Therefore, the IRE was recommended to be applied with high frequency and low voltage.

Age-related macular degeneration (AMD) is one of the major causes of visual loss among the elderly. It causes degeneration of cells in the macula. Early diagnosis can be helpful in preventing blindness. Drusen are the initial symptoms of AMD. Since drusen have a wide variety, locating them in screening images is difficult and time-consuming. An automated digital fundus photography-based screening system help overcome such drawbacks. The main objective of this study was to suggest a novel method to classify AMD and normal retinal fundus images.
The suggested system was developed using convolutional neural networks. Several methods were adopted for increasing data such as horizontal reflection, random crop, as well as transfer and combination of such methods. The suggested system was evaluated using images obtained from STARE database and a local dataset.
The local dataset contained 3195 images (2070 images of AMD suspects and 1125 images of healthy retina) and the STARE dataset comprised of 201 images (105 images of AMD suspects and 96 images of healthy retina). According to the results, the accuracies of the local and standard datasets were 0.95 and 0.81, respectively.
Diagnosis and screening of AMD is a time-consuming task for specialists. To overcome this limitation, we attempted to design an intelligent decision support system for the diagnosis of AMD fundus using retina images. The proposed system is an important step toward providing a reliable tool for supervising patients. Early diagnosis of AMD can lead to timely access to treatment.

In radiotherapy treatment planning system (TPS), basic input is the data from computed tomography (CT) scan, which takes into account the effect of inhomogeneities in dose calculations. Measurement of CT numbers may be affected by scanner-specific parameters. Therefore, it is important to verify the effect of different CT scanning protocols on Hounsfield unit (HU) and its impact on dose calculation. This study was carried out to analyse the effect of different tube voltages on HU for various tissue substitutes in phantom and their dosimetric impact on dose calculation in TPS due to variation in HU–relative electron density (RED) calibration curves.
HU for different density materials was obtained from CT images of the phantom acquired at various tube voltages. HU-RED calibration curves were drawn from CT images with various tissue substitutes acquired at different tube voltages used to quantify the error in dose calculation for different algorithms. Doses were calculated on CT images acquired at 120 kVp and by applying CT number to RED curve obtained from 80, 100, 120, and 140 kVp voltages.
No significant variation was observed in HU of different density materials for various kVp values. Doses calculated with applying different HU-RED calibration curves were well within 1%.
Variation in doses calculated by algorithms with various HU-RED calibration curves was found to be well within 1%. Therefore, it can be concluded that clinical practice of using the standard HU-RED calibration curve by a 120 kVp CT acquisition technique is viable.

In digital radiography, radiographers tend to increase exposure factors to acquire an acceptable image quality thereby increasing radiation dose to patients. Regarding this, the present study aimed to re-evaluate the exposure parameters and to ascertain the entrance surface dose (ESD) and effective dose (ED) of posterior-anterior (PA) chest, abdomen, and anterior-posterior (AP) lumbosacral spine radiography.
This study was conducted on 180 physically able patients with age of 20-60 years and weight of 60-80 kg referred to Hospital Sultan Haji Ahmad Shah (HOSHAS) and Hospital Tengku Ampuan Afzan (HTAA).Image acquisition was performed using digital radiography. The ESD and ED were determined using CALDose_X 5.0 software.
The ESD and ED for PA chest were 0.098 mGy and 0.012 mSv in HOSHAS, while in HTAA were 0.161 mGy and 0.021 mSv respectively. Regarding the abdomen, the ESD and ED were 2.57 mGy and 0.311 mSv in HOSHAS and 2.16 mGy and 0.262 mSv in HTAA respectively. For AP lumbosacral spine, the ESD and ED for HOSHAS were 2.65 mGy and 0.222 mSv, while in HTAA were 2.357 mGy and 0.201 mSv respectively.
The findings revealed the use of high kVp, automatic exposure control, correct focus image receptor distance, tight collimation and additional filter resulted in a lower ESD. The ESD and ED obtained in this study were comparable with those reported by other studies and lower than the values recommended by the United Nations Scientific Committee on the Effects of Atomic Radiation in 2008.

There is a strong need for developing clinical technologies and instruments for prompt tissue assessment in a variety of oncological applications as smart methods. Elastic scattering spectroscopy (ESS) is a real-time, noninvasive, point-measurement, optical diagnostic technique for malignancy detection through changes at cellular and subcellular levels, especially important in early diagnosis of invasive skin cancer, melanoma. In fact, this preliminary study was conducted to provide a classification method for analyzing the ESS spectra. Elastic scattering spectra related to the normal skin and melanoma lesions, which were already confirmed pathologically, were provided as input from an ESS database.
A program was developed in MATLAB based on singular value decomposition and K-means algorithm for classification.
Accuracy and sensitivity of the proposed classifying method for normal and melanoma spectra were 87.5% and 80%, respectively.
This method can be helpful for classification of melanoma and normal spectra. However, a large body of data and modifications are required to achieve better sensitivity for clinical applications.

The ultimate goal of radiation treatment planning is to yield a high tumor control probability (TCP) with a low normal tissue complication probability (NTCP). Historically dose volume histogram (DVH) with only volumetric dose distribution was utilized as a popular tool for plan evaluation hence present study aimed to compare the radiobiological effectiveness of the cobalt-60 (Co-60) gamma photon and 6MV X-rays of linear accelerators (Linac) in the radiotherapy of head and neck tumors.
TCP and NTCP were calculated using DVH through the BIOPLAN software developed by Sanchez-Nieto and Nahum . The treatment planning was performed for all the patients using both treatment modalities (i.e., Co-60 and 6 MV Linac). The TCP was also manually calculated using a mathematical formula proposed by Brenner’s et al.
The average TCP calculated by the BIOPLAN for Co-60 and 6 MV X-rays were 44.6% and 60.8%, respectively. Furthermore, the average NTCPs obtained for the organ at risk, namely optic nerve, for Co-60 and 6 MV X-ray were 0.24 % and 0.03 %, respectively. Regarding the spinal cord, the average NTCPs for Co-60 gamma photon and 6 MV X-ray of Linac were 0.05 % and 0.002%, respectively.
As the findings of the present study indicated, Co-60 unit could provide comparable TCP along with minimal NTCP, compared to the high-cost technologies of Linac. The design of treatment plans based on the radiobiological parameters facilitated the judicious choice of physical parameters for the achievement of high TCP and low NTCP.