
Alireza MehdizadehShiraz University of Medical Sciences | SUMS · Department of Medical Physics
Alireza Mehdizadeh
MD,PhD
About
152
Publications
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Introduction
Joined again to SUMS as Assistant professor in 2009,working for department of Medical physics,school of medicine,as deputy editor work in journal of biomedical physics and engineering(www.jbpe.org)
senior physicist at Chamran Hospital.
Since 2010,working on history of medicine and start journal of Research in history of medicine(www.rhm.ir) as editor in chief.
Additional affiliations
May 2010 - present
Education
March 2005 - April 2009
September 1991 - September 2002
Publications
Publications (152)
In a recent article, Gale et al. [1] discussed that the adaptation of living organisms to higher levels of ionizing radiation, when they moved from water to land, may be due to the translocation of hematopoietic stem cells to the bone marrow. Gale et al. explore the possibility that this translocation occurred as an evolutionary response to increas...
Multimodal image registration is a key for many clinical image‐guided interventions. However, it is a challenging task because of complicated and unknown relationships between different modalities. Currently, deep supervised learning is the state‐of‐theart method at which the registration is conducted in end‐to‐end manner and one‐shot. Therefore, a...
Objective: Detection of sensitive signs in many work environments with automated systems (aviation industry, flight safety tower, maritime industry, monitoring in the military industry, etc.) is essential and requires constant visual attention. Therefore, the aim of this study was to investigate the effect of forehead cooling on the accuracy of sta...
Background
Controlling upright posture entails acute adjustments by the neuromuscular system to keep the center of mass (COM) within the limits of a relatively small base of support. Sudden displacement of the COM triggers several strategies and balance recovery mechanisms to prevent excessive COM displacement.
New method
We have examined and quan...
In medicine, image registration is vital in image-guided interventions and other clinical applications. However, it is a difficult subject to be addressed which by the advent of machine learning, there have been considerable progress in algorithmic performance has recently been achieved for medical image registration in this area. The implementatio...
Extensive network receptive field is key for unsupervised affine registration because instead of deformable registration that takes care of local subtleties, the affine registration is global so that the last layers need to see big patches of the organ‐in‐interest. To extend the network's receptive field, we need to go for deeper networks, which ca...
Although surgery is the treatment of choice for early-stage non-small-cell lung carcinoma, almost two-thirds of patients do not have acceptable pulmonary function for extensive surgeries. The alternative approach for this large group of patients is sublobar resection along with low-dose-rate (LDR) brachytherapy (BT). However, patients with resected...
Purpose
This study aimed to compare two different concentrations of Cobalt-zinc (Co–Zn) ferrite (Co0.6 Zn0.4 Fe2O4 or CZFO) nanoparticles (NPs) included 1.5 and 2.5 mg Fe/kg coated with dimercaptosuccinic acid (DMSA) based on T2-and T2*- weighted magnetic resonance imaging (MRI) of rats liver.
Materials and methods
The structural and crystal phase...
In medicine, image registration is vital in image-guided interventions and other clinical applications. However, it is a difficult subject to be addressed which by the advent of machine learning, there have been considerable progress in algorithmic performance has recently been achieved for medical image registration in this area. The implementatio...
Background
Distal femur fracture is considered one of the most common fractures due to high-energy traumas such as car accidents or low-energy traumas such as osteoporosis. Locking plates are orthopedic implants used for stabilized femur fracture. Thus, designing a bone plate fitted exactly with the patient’s bone and correctly fixing bone segments...
Introduction: Thyroid cancer is a malignancy accounting for less than 1% of human malignancies. This study aim was to investigate the effect of Senna tablets (C-Lax®) in increasing the dose of radiation excreted in patients who underwent iodine therapy in the iodine treatment center of Namazi Hospital of Shiraz University of Medical Sciences at dis...
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Detection of red lesions in color retinal images is a critical step to prevent the development of vision loss and blindness associated with diabetic retinopathy (DR). Microaneurysms (MAs) are the most frequently observed and are usually the first lesions to appear as a consequence of DR. Therefore, their detection is necessary for mass screening of...
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Background:
Falling is a major cause of disability and death among elderly people. Therefore, a clear understanding of fall mechanism is necessary for providing preventative and treatment methods. Several fall simulation protocols have been introduced to study lost of balance in a laboratory setting.
New Method
We have explained and examined a new...
Objectives:
Our study aimed to apply the apparent diffusion coefficient (ADC) values to quantify the differences between low- and high-grade glioma tumors.
Methods:
We conducted a multicenter, retrospective study between September to December 2019. Magnetic resonance imaging (MRI) diffusion-weighted images (DWIs), and the pathologic findings of...
Abstract Retinal blood vessel segmentation and analysis is critical for the computer‐aided diagnosis of different diseases such as diabetic retinopathy. This study presents an automated unsupervised method for segmenting the retinal vasculature based on hybrid methods. The algorithm initially applies a preprocessing step using morphological operato...
The aim of this study was to synthesize and characterize the dimercaptosuccinic acid (DMSA) cobalt–zinc (Co–Zn) ferrite magnetic nanoparticles (NPs) and their efficiency as a contrast agent in in vivo MR imaging of rat liver. Co–Zn ferrite NPs were synthesized by the thermal decomposition method and stabilized by DMSA. The NPs were characterized by...
Image-guided interventions are saving the lives of a large number of patients where the image registration should indeed be considered as the most complex and complicated issue to be tackled. On the other hand, a huge progress in the field of machine learning has recently made by the possibility of implementing deep neural networks on the contempor...
In recent years, the preference for using lead-free radiation protection shields has increased because of concerns regarding lead poisoning and leakage. In medical and research laboratories, glass shields are preferred because of their transparency. In this study, various glass shields were examined and compared based on the international standards...
Background:
Cervical cancer cells are known as radioresistant cells. Current treatment methods have not improved the patients' survival efficiently; thus, new therapeutic strategies are needed to enhance the efficacy of radiotherapy. Gold nanomaterials with different shapes and sizes have been explored as radiosensitizers. The present study compar...
Background: Cervical cancer cells are known as radioresistant cells. Current treatment methods have not improved the patients’ survival efficiently; thus, new therapeutic strategies are needed to enhance the efficacy of radiotherapy. Gold nanomaterials with different shapes and sizes have been explored as radiosensitizers. The present study compa...
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- Abstract:
Although surgery is the treatment of choice for early-stage non-small-cell lung carcinoma (NSCLC), almost two-thirds of patients do not have acceptable pulmonary function for extensive surgeries such as lobectomy or pneumonectomy. The alternative approach for this large group of patients is sublobar resection along with low-dose-rate...
- Abstract:
In recent years, the preference for using lead-free radiation protection shields has increased because of lead poisoning and leakage concerns. In medical and research laboratories, glass shields are preferred because of their transparency. In this study, various glass shields were examined and compared based on international standards....
Computer-Aided Diagnosis systems are required to extract suitable information about retina and its changes. In particular, identifying objects of interest such as lesions and anatomical structures from the retinal images is a challenging and iterative process that is doable by image processing approaches. Microaneurysm (MAs) are one set of these ch...
Background:
Overuse of antibiotics is a cause of bacterial resistance. It is known that electromagnetic waves emitted from electrical devices can cause changes in biological systems. This study aimed at evaluating the effects of short-term exposure to electromagnetic fields emitted from common Wi-Fi routers on changes in antibiotic sensitivity to...
Background: Overuse of antibiotics is a cause of bacterial resistance. It is known that electromagnetic waves emitted from electrical devices can cause changes in biological systems. This study aimed at evaluating the effects of short-term exposure to electromagnetic fields emitted from common Wi-Fi routers on changes in antibiotic sensitivity to o...
Image-guided interventions are saving the lives of a large number of patients where the image registration problem should indeed be considered as the most complex and complicated issue to be tackled. On the other hand, the recently huge progress in the field of machine learning made by the possibility of implementing deep neural networks on the con...
The design of organic/inorganic polymer nanoparticles-based hybrids is promising for gamma ray sensor systems. Here, we design semiconducting nanocomposite system for efficient gamma ray harvesting system where cadmium telluride (CdTe) quantum dots act as dopant and poly(N-vinyl carbazole) (PVK) polymer acts as host. Highly crystalline 1-dodecaneth...
We have recently reported the synthesis and characterization of gold-coated iron oxide nanoparticle and demonstrated such a nanoparticle (Au@Fe2O3 NP) was able to significantly enhance the lethal effects of photo-thermo-radiotherapy. The purpose of this study was to determine the mechanisms behind such an enhancement by investigating the changes in...
A report published in the New York Times "The 5G Health Hazard, That Isn't, How one scientist and his inaccurate chart led to unwarranted fears of wireless technology" addressed the controversies over the safety of 5G technology. Unfortunately, the approach of New York Times in this report is not scientific. William J. Broad in his report published...
Early detection of microaneurysms (MAs), the first sign of Diabetic Retinopathy (DR), is an essential first step in automated detection of DR to prevent vision loss and blindness. This study presents a novel and different algorithm for automatic detection of MAs in fluorescein angiography (FA) fundus images, based on Radon transform (RT) and multi-...
Novel 3 dimensional radiation sensors using reduced graphene oxide (rGO) nanoflakes in polymethyl methacrylate matrix as sensing material were synthesized and fabricated to measure the dose rate of gamma radiation. A detailed characterization of the prepared reduced graphene oxide using X-ray diffraction (XRD), thermal gravimetric analysis (TGA), a...
The reduced graphene oxide nanosheets (rGO) were synthesized by chemical methods. A detailed characterization of the prepared reduced graphene oxide using XRD, FTIR, HRTEM and … is presented. Novel 3dimensional radiation sensors using solvent-assisted dispersion of rGO nano flakes in different matrices were fabricated to measure the dose rate of ga...
Background: Osteoporosis is a systemic skeletal disease characterized by low
bone mineral density (BMD) and micro-architectural deterioration of bone tissue,
leading to bone fragility and increased fracture risk. Since Panoramic image is a
feasible and relatively routine imaging technique in dentistry; it could provide an
opportunistic chance for s...
Background: Osteoporosis is a systemic skeletal disease characterized by low bone mineral density (BMD) and micro-architectural deterioration of bone tissue, leading to bone fragility and increased fracture risk. Since Panoramic image is a feasible and relatively routine imaging technique in dentistry; it could provide an opportunistic chance for s...
Background: Electromagnetic fields (EMF) with different intensities are widely used at home, offices and public places.Today, there is a growing global concern about the effects of human exposure to EMFs. Epilepsy is one of the most common chronic neurological diseases, affecting 50 million people of all ages worldwide. We aimed to investigate the...
The aim of this report is to present a new two-piece thyroid-neck phantom produced by
the concurrent use of epoxy resin and poly(methyl methacrylate) (PMMA: plexiglass)
soft tissue equivalent materials. Accordingly, mass attenuation coefficients of the epoxy
resin and the plexiglass compounds were obtained from simulation (NIST XCOM
3.1) and measur...
Background:
Electromagnetic fields (EMF) with different intensities are widely used at home, offices and public places.Today, there is a growing global concern about the effects of human exposure to EMFs. Epilepsy is one of the most common chronic neurological diseases, affecting 50 million people of all ages worldwide. We aimed to investigate the...
The aim of this report is to present a new two-piece thyroid-neck phantom produced by the concurrent use of epoxy resin and poly(methyl methacrylate) (PMMA: plexiglass) soft tissue equivalent materials. Accordingly, mass attenuation coefficients of the epoxy resin and the plexiglass compounds were obtained from simulation (NIST XCOM 3.1) and measur...
Mercury is a well-known toxic element that is found in various forms in nature. Recently,
dental amalgams have been recognized as a new source of mercury. This study was
carried out under in vitro condition; the amount of mercury released from teeth
restored with amalgams in the presence of Wi-Fi router radiation (non-ionizing
radiation) and X-ray...
Endotracheal tube (ETT) obstruction, either complete or partial, is a serious life threatening complication in intubated patients. Therefore, implementing a practical method to diagnose this condition is vital. Alteration in respiratory sound signals caused by ETT occlusion can be used for early detection of obstruction. This study is aimed to asse...
Context: Previous studies have reported direct relationship between tumor reduction and its platinum concentration following platinum-based (Pt-based) chemotherapy. However, quantitative data of tumor platinum concentration have not yet been reported for the most common cancers.
Aims: Determination of tumor platinum concentration of breast, lung,...
Objectives: Precise determination of dose distribution around low-energy brachytherapy sources as well as considering tissue heterogeneity is crucial for optimized treatment planning. This study is aimed at determination and mathematically formulation of American Association of Physicists in Medicine Task Group No. 43 (AAPM TG-43) dosimetry paramet...
Background
A new treatment approach for most patients who have undergone early stage non-small-cell lung carcinoma (NSCLC) is wedge resection plus permanent implant brachytherapy. However, the specification of dose to medium at low energies especially in heterogeneous lung is unclear yet.
Objective
The present study aims to modify source strength...
Persian scholars greatly influenced the advancement of medical sciences during the Middle Ages. As a review of the books surviving from that time shows, infectious diseases was one main field of interest for these scientists. Among this group of health problems, rabies was specifically described by Persian physicians, particularly by Avicenna (980...
Despite major progress in radiotherapy, exponential attenuation of initial photons due to the nature of their interaction with matter has remained as the most important challenge. Photons have no well-defined range and their doses are reduced exponentially. Therefore, tissues located before and after the tumors receive a significant dose. Today, ne...
Background & Objective: Long term exposure to ionizing radiation and its complication have always been concerned by medical physicists. Some previous studies have shown that radiation dose to urology surgeons and involved personnel during mini C-arm fluoroscopy guided surgeries exceeds the secure threshold in some cases. In this study, we intend to...
Functional significance of the neural oscillations has been debated since long. In particular, oscillations have been suggested to play a major role in formation of communication channels between brain regions. It has been previously suggested that gamma coherence increases during communication between hemispheres when subjects perceive a horizonta...
Background:
Nowadays, magnetic nanoparticles (MNPs) have received much attention because of their enormous potentials in many fields such as magnetic fluid hyperthermia (MFH). The goal of hyperthermia is to increase the temperature of malignant cells to destroy them without any lethal effect on normal tissues. To investigate the effectiveness of ca...
Background:
Clay has been used for its nutrition, cosmetic, and antibacterial properties for thousands of years. Its small particle size, large surface area, and high concentration of ions have made it an interesting subject for pharmaceutical research. There have been studies on scavenging foreign substances and antibacterial properties of clay m...
Surface plasmon resonance effect of gold nanostructures makes them good candidates for photothermal therapy (PTT) application. Herein, gold-ferrite nanocomposite (GFNC) was synthesized and characterized as a photothermal agent in PTT. The aim of this study was to investigate the effect of GFNC upon laser irradiation on treatment of cancer in mice b...
A large body of evidence now indicates that the amount of mercury released from dental amalgam fillings can be significantly accelerated by exposure to radiofrequency electromagnetic fields (RF-EMFs) such as common mobile phones and magnetic resonance imaging (MRI). Studies performed on the increased microleakage of dental amalgam restorations afte...
During the final hours of pregnancy, uterine contractions cause the foetus to move through the birth canal and leave the mother’s body. Haly Abbas (died 982-994 CE), is believed to be the first writer to explain the role of these contractions. However, this concept had in fact been described in the text titled Bab-e-Borzouyeh, written four centurie...
Background:
Nowadays, mothers are continuously exposed to different sources of electromagnetic fields before and even during pregnancy. It has recently been shown that exposure to mobile phone radiation during pregnancy may lead to adverse effects on the brain development in offspring and cause hyperactivity. Researchers have shown that behavioral...
Mobile Health (mHealth) is an evolving and rapidly developing field which has the potential to play a part in the transformation of healthcare and increase its quality and efficiency. Shiraz International mHealth Seminar brought together researchers, policy makers, information, communication and technology programmers, academics and civil society r...
Iron oxide nanoparticles, such as ferrites, offer some attractive possibilities in biomedicine, especially in MRI applications. The objective of this study is to investigate the effectiveness of dextrin-coated zinc-iron ferrite nanoparticles (IFNPs) as an MRI contrast agent in in vivo and in vitro media. IFNPs were synthesized by an aqueous precipi...
(177)Lu-ethylenediaminetetramethylene phosphonic acid (EDTMP) is presently suggested as an excellent bone seeking radionuclide for developing metastatic bone pain (MBP) palliation agent owing to its suitable nuclear decay characteristics. To find the exact dosage and its efficiency, this clinical study was performed on the human being, using (177)L...
Application of superparamagnetic iron oxide nanoparticles (NPs) as a negative contrast agent in magnetic resonance imaging (MRI) has been of widespread interest. These particles can enhance contrast of images by altering the relaxation times of the water protons. In this study, dextrin-coated zinc substituted cobalt-ferrite (Zn0.5Co0.5Fe2O4) NPs we...
The branching pattern of retinal vessels may be affected in Behçet's Disease (BD). Fractal analysis can be used as a new method to quantify the changes of the vascular branching pattern. In this study, we examined, for the first time, the relationship between retinal fractal dimension (D f) and retinal vascular changes seen in patients with BD.
We...
Objective: To ascertain the technique and volume of injection increasing the success rate of en-doscopic VUR treatment, we develop a novel method to numerically describe the relationship be-tween intramural ureter anatomy, intravesical pressure, and the theoretical mound height needed for adequate treatment. Methods: The main purpose of this study...