International Conference on Medical Physics August 03-05, 2015 Birmingham, UK

Biography:

Dr Xianfeng Fan is a senior lecturer and leads a research group with 8 members in the Institute for Materials and Processes, School of Engineering at The University of Edinburgh. He obtained a PhD degree from the University of Birmingham and then worked a Research Fellow in the Birmingham Positron Imaging Centre for 8 years. Dr Fan previously worked on colloidal and interfacial phenomena, materials separation, positron emission particle tracking and powder technology. He has authored or co-authored over 160 journal and conference publications.

Abstract:

Copper radioisotopes have been used in nuclear medicine and in positron emission particle tracking. The separation of copper radioisotopes from a nickel target has been conducted through solvent extraction or anion exchange. However, anion exchange methods consume a large amount of chemicals, and after separation the residual nickel in the radioactive products is at quite a high level which may be harmful to human health. A commonly held opinion is that cationic exchangers have very similar thermodynamic complexation constants for metallic ions with identical charges, therefore making the separation very difficult, or impossible. Our research indicates that an effective separation can be achieved by ammonium modified Chelex-100. The selectivity of Chelex-100 for Cu and Ni ions not only depends on its thermodynamic complexation constant, but also markedly varies with the concentration of mobile H+, the structure and arrangement of the polymer chains. Through controlling the intermolecular interaction of the polymer bed, over 99.9% of Ni was stripped out, but 100% of copper radioisotopes remained in the separation column. The separation is much more effective, simple and economical in comparison with the common method of anion exchange. This significant improvement will make subsequent labelling much easier, and reduce the uptake of Ni and chelating agents by patients, therefore both the stress on human body associated with clearing the chemicals from blood and tissue, and the risk of various types of acute and chronic disorder due to exposure to Ni.

Biography:

Fridon Shubitidze has completed his PhD in radio-physics at the age of 26 years from Tbilisi State University and postdoctoral studies from National Technical University of Athens. He is an associate professor at Thayer School of Engineering at Dartmouth College, leader of the electromagnetic sensing group, a premier in geophysical and biomedical applications, and the recipient of the Munitions Response Project of the Year Award given by the DoD Strategic Environmental Research and Development Program in 2011 for developing AMF technologies for subsurface targets detection and classification. He has published more than 200 papers in reputed journals and conference proceeding.

Abstract:

Magnetic nano-particle hyperthermia (MNPH) is minimally invasive thermal technique for cancer therapy. One of main characteristics of MNPs for clinical hyperthermia is a high specific absorption rate (SAR), which depends on the applied magnetic field frequency, strength and MNP properties. During MNPH therapy a coil produces alternating electric and magnetic fields. The alternating magnetic field (AMF) penetrates inside tissue and activates MNPs in cancerous tissues, where else the alternating electric field produce undesirable eddy currents within normal tissue. Since, the AMF from a coil decays rapidly (as 1/R2); therefore, to use magnetic hyperthermia for deep tumors, such as pancreatic, prostate, rectum and etc cancers, a high-magnitude transmitter current is required in the coil. High transmitter currents also produce high electric fields E and eddy currents J within normal tissue that cause non-specific heating (J.E), which limits the applicability of MNP hyperthermia for deep sitting cancers. To overcome this problem, recently we have develop next generation Dartmouth MNP, with high SAR at low AMF strength, and a new device for guiding and delivering transmitted magnetic fields to deep tumors and for minimizing undesirable eddy currents heating in normal tissues. In this presentation, first the system’s AMF delivery and focusing performance will be described and illustrated using both modelled and measured data, then temperature distributions in a conducting phantom with and without the flexible magnetic device will be shown, and finally, applicability of the device for clinically MNPH therapy will be demonstrated in combination with the next generation MNP.

Biography:

Double major in Material Science Engineering (Universidade Federal de São Carlos - Brasil - 1981) and Physics (Universidade de São Paulo - Brasil - 1981), Is PhD from MIT (1987) and Livre - Docente (1989) and Full Professor by University of São Paulo (1993). Has his activities based on two pillars: laser cooling and trapping of neutral atoms and applications of optics and biophotonics. Has published over 350 papers in international journals with over 2500 citations. Has supervised more than 50 graduate students.

Abstract:

The fundamental questions to be answered with our Biophotonics studies are: How to approach photodynamic therapy concerning dosimetry and tumor cells selectivity? This aspect shall greatly contribute to the clinical protocols. What must be done to understand the processes related to PDT that determines the amount/volume of tissue that become necrotic? Is photodynamic therapy using two-photon excitation practicable? How should wide-field and fluorescence imaging techniques be combines for better tumor diagnosis? How much influence light should exert into cells metabolic processes so that photonic techniques may contribute to metabolism reorganization? How to deal with melanoma cells intrinsic characteristics to improve its detection and treatment? How to broaden photodynamic approaches for microorganisms? How to design new photosensitizers with more specific action? Moreover, we plan to carry on clinical studies in cancer and tumor optical diagnosis, as well as new clinical protocols for the treatment of lesions and HPV (human papilloma virus) infection, and to develop and implement optical methods for detection of several tissue abnormalities. We are representing one of scientific center in Brazil with know-how in establishment of clinical partnership with several institutions, incorporating new technologies for healthcare sciences.

Biography:

Abstract:

Introduction: Breast cancer is a major public health problem in women from developed and developing countries. Early detection and treatment of breast cancer increase the cure rate and provide optimal treatment. In regularly examination, ultrasound (US) is a more convenient and safer tool than mammography. Objective: To explore diagnostic potential of computer aided texture analysis (TA) methods in differentiation benign and malignant breast cancers by ultrasound imaging and to compare the discrimination performance of the applied texture analysis methods. Materials and methods. Database consisted of ultrasound images of 91 breast patients including 35 benign and 56 malignant tumors. Two slices per patient was loaded in Mazda Software for automatic texture analysis. Regions of interests (ROIs) were defined within the abnormal part of the breast ultrasound images. Gray levels within a ROI normalized according to three normalization schemes: N1: default or original gray levels, N2: +/- 3 Sigma or dynamic intensity limited to µ+/- 3σ, and N3: present intensity limited to 1% - 99%. Up to 270 multi scale texture features parameters per ROIs per each normalization schemes were computed from well known statistical methods employed in Mazda software. From the statistical point of view, all calculated texture features parameters are not useful for texture analysis. So, the features based on maximum Fisher coefficient and minimum probability of classification error and average correlation coefficients (POE+ACC) eliminated to 10 best and most effective features per normalization schemes. We analyze this feature under two standardization states (standard (S) and nonstandard (NS)) with Principle Component Analysis (PCA), Linear Discriminant Analysis (LDA) and Non Linear Discriminant Analysis (NDA). The 1NN classifier was performed to distinguish between benign and malignant tumors. The confusion matrix and Receiver operating characteristic (ROC) curve analysis were used for formulation of more reliable criteria of the performance of employed texture analysis methods. classification method performance. Results. Significant separation between benign and malignant breast tumors was by standard feature parameters extracted by Fisher coefficient under default and 3σ normalization schemes via NDA with accuracy of 97.8%, sensitivity of 94.28%, specificity of 85.5% and the area under the ROC curve value of 0.97. While the performance of the PCA and LDA was good and more or less the same with no significant statistical differences. Conclusions: It is shown that automatic texture analysis can effectively discriminated benign and malignant breast cancers and thus has the potential to increase confidence of radiologist in correctly distinguishing US images of the breast with no need to other radiological and or pathological examination. Key words. Ultrasound; breast tumors; texture analysis; PCA; NDA; LDA; 1-NN classifier

Biography:

Dr Xianfeng Fan is a senior lecturer and leads a research group with 8 members in the Institute for Materials and Processes, School of Engineering at The University of Edinburgh. He obtained a PhD degree from the University of Birmingham and then worked a Research Fellow in the Birmingham Positron Imaging Centre for 8 years. Dr Fan previously worked on colloidal and interfacial phenomena, materials separation, positron emission particle tracking and powder technology. He has authored or co-authored over 160 journal and conference publications.

Abstract:

Copper radioisotopes have been used in nuclear medicine and in positron emission particle tracking. The separation of copper radioisotopes from a nickel target has been conducted through solvent extraction or anion exchange. However, anion exchange methods consume a large amount of chemicals, and after separation the residual nickel in the radioactive products is at quite a high level which may be harmful to human health. A commonly held opinion is that cationic exchangers have very similar thermodynamic complexation constants for metallic ions with identical charges, therefore making the separation very difficult, or impossible. Our research indicates that an effective separation can be achieved by ammonium modified Chelex-100. The selectivity of Chelex-100 for Cu and Ni ions not only depends on its thermodynamic complexation constant, but also markedly varies with the concentration of mobile H+, the structure and arrangement of the polymer chains. Through controlling the intermolecular interaction of the polymer bed, over 99.9% of Ni was stripped out, but 100% of copper radioisotopes remained in the separation column. The separation is much more effective, simple and economical in comparison with the common method of anion exchange. This significant improvement will make subsequent labelling much easier, and reduce the uptake of Ni and chelating agents by patients, therefore both the stress on human body associated with clearing the chemicals from blood and tissue, and the risk of various types of acute and chronic disorder due to exposure to Ni.

Biography:

Amir S. H. Rozatian: Assistant Professor of Condensed Matter Physics, Department of Physics, University of Isfahan, Hezar Jarib Street, Isfahan 81746-73441, Iran. Marjan Tajik: PhD Student, Department of Physics, University of Isfahan, Hezar Jarib Street, Isfahan 81746-73441, Iran. Farid Semsarha: Assistant Professor of Physics, Radiation Applications Research School, Nuclear Science and Technology Institute, P. O. Box: 11365-3486, Tehran, Iran.

Abstract:

Human awareness of ionizing radiations and their harmful effects on biological materials has a 100-year history starting with the discovery of X-rays. Radiation induced DNA damage such as single strand break (SSB), double strand break (DSB), base damage (BD), DNA–DNA and DNA–protein cross link can disrupt normal biological processes and cause chromosome aberrations, mutations or cell death. In this study, the total yields of simple SSB and DSB induced by electrons with different energies associated with the energies of the ultrasoft X-rays, between 0.28 and 4.55 keV, have been calculated in Charlton and Humm volume model using the Geant4-DNA extension of the Geant4 toolkit. A comparison between the obtained results and other experimental and theoretical data shows the suitability of this simple model of DNA for calculating the total damage with the advantages of reducing the complexity of the simulations and decreasing the computational time. Also, it has been found that in the low energy region (under 5 keV), the yield of the total SSB remains nearly independent of the initial electron energy while the DSB yield increases with decreasing energy. Moreover, a direct dependency between DSB induction, RBE value and the mean lineal energy, as a microdosimetry quantity, has been observed. Meanwhile, it has revealed that the threshold energy of 10.79 eV to calculate the total strand breaks yields results in a good agreement with the theoretical and experimental data while the other threshold energies such as 12.61 eV or 17.5 eV result in significant difference.

Biography:

Mohammad has completed his BSc in Alquds university / Medical Imaging 2010, and MSc in Nuclear Medicine and targeted therapy from Istanbul University 2015. In the same year he started to be PhD Candidate in Istanbul University / School of Medicine/Nuclear Medicine Dept. He has scientific interests in the field of internal therapy dosimetry and Molecular & Multimodality Imaging, dose- limiting tissues Protection during therapy and clinical trials using radioactive tracers .

Abstract:

Aim: Dosimetry is an alternative strategy to the traditional fixed radioactive iodine treatment in metatstatic thyroid cancer therapy.Pretherapy dosimetry is increasingly recommended to calculated the maximum tolerable Activity for each patient in order to deliver absorbed dose not exceed 2 Gy for the red bone marrow and meanwhile optimization the response level of desired targeted lesions. Materials and Methods: 14 patients (9 female ,5 Male and Mean age 44±15.84 y ,TSH 65±43 µIU/ml,HTC 38.43±3.81 ng/ml, 5 patients were prepared by rhTSH; 9 patients by thyroid withdrawal) suffering from metastatic differentiated thyroid cancer were submitted to pretherapy maximum safe activity and lesion absorbed dose protocol to establish successive therapy using OLINDA/EXM Software and five different dosimetry Methods for comparison purposes. Dual head scintillation camera was utilized to measure whole body and lesions activities by drawing region of intrest adjacent to whole body and lesion contours and performing attenuation correction Besides to Blood samples collection which were measured in well –gama counter at several time points 2.6.24.48.72.96.144hours after oral administration of Radioiodine tracer (2mCi). To verify normal back ground count rate, 1 minute acquistion was performed before each whole body scan and subtracted from the related scan’s count.The neccesssery data were collected and modified according to the parameters of the dosimetry methods adopted by OLINDA/EXM, Wessels et al,Traino et al,Siegel et al,Shen et al ,and Keizer et al . Results: According to OLINDA/EXM software mean absorbed dose from tracer activity was 3.11±1.76mGy/mCi(for thyroid withdrawal 4.02±2.06 mGy/mCi ; and rTSH patients was 1.96±0.44) ,Wessels et al was 3.27±1.9mGy/mCi,Traino et al was 2.68±1.53 mGy/mCi,Kiezure et al was 2.2±1.16mGy/mCi,Siegal et al was 2.56±1.86 mGy/mCi , and Shen et al was 4.05±3.4 mGy/mCi. mean absorbed dose to distal metastatic lesions was 3.4±4.5 Gy/mCi. The deviation between the results of OLINDA/EXM software and the other dosimetry methods was variable 5.1%, -13.8%, 30%, -17%, and -29%. Discussion: Mean absorbed dose of bone marrow in Our study using OLINDA/EXM as reference for thyroid withdrawal patients was (4.02±2.06 mGy/mCi) similar to findings reported by Hänscheid H et al inwhich Aaverage bone-marrow doses were determined as average 4.2mGy/mCi (3.2 – 8.5 mGy/mCi) .For the patients with euthyrodisim (using rTSH) the absorbed dose was significantly lower ( mean: 1.96±0.44) And also within a range reported by other publishers (2.2-7.2mGy/mCi) for euthyroid .Chiese et al reported bone marrow absorbed dose using blood –based dosimetry 1.7-6.2 mGy/mCi .in this study four patients were prepared by exogemous TSH and absorbed dose of bone marrow was (1.59-7.26mGy/mCi) which is close to Keizer et al findings (2.2-7.2mGy/mCi) for euthyroid patients dosimetry . Conclusion Our study demonstrated that there is no statistically significant difference between the results reported by Wessels et al ,Shen et al and OLINDA/EXM for estimating red bone marrow dose .The amount of activity calculated to deliver 80 Gy for some distant metastatic lesion was< 250 mCi which represent the traditional maximum fixed dose.

Biography:

Marco Dominietto is a medical physicist who completed his PhD in Biomedical Engineering at the ETH (Zurich, Switzerland). He moved to basic oncology research after five years of clinical experience. His research focuses on tumor development and images analysis both in animal models and human beings. He actually works at the Biomaterial Science Center at the University of Basel where he also develops energy harvesting strategies from human body to power artificial muscles.

Abstract:

Cancer is a multifactorial and heterogeneous disease. The corresponding complexity appears at multiple levels, from molecular to physiological behavior, and determine the different evolution of the same disease in different patients or the different response to the same therapy. Such complexity can be characterized by a set of quantitative phenotypic observables recorded in time-space resolved dimensions by using multimodal imaging approaches. These observables, called here features, measure single variables that account for single physiological processes both in tumor and hosting tissue, e.g. tumor oxygenation, vascular permeability, glucose consumption, etc. Clearly, in tumor progression all these features interact together and determine its evolution. The integration of all these information in a comprehensive framework is therefore one of the key to understand cancer disease in its entirety. Complex networks offer in this regard an ideal solution for the integration of multiple information layers at different space and time scales. Single parts of the tumor that correspond to voxel volumes on imaging readouts, constitute the nodes of the network that are linked together on the basis of the features distributions. Statistical inference on topological properties and dynamic evolution of the network allows the determination of the stage of the tumor and predicts its evolution. Moreover, treatment as chemotherapy or radiotherapy can be accounted as perturbation of the network. The advantages of this approach are in terms of a) integration of several features in a single framework, b) estimation of the interaction between tumor and hosting tissue and c) prediction of treatment efficacy.

Biography:

Kokou ADAMBOUNOU was graduated as Medical Doctor in 2007 from University of Lomé (Togo) and had his certification in Diagnostic Radiology from University of Abidjan (Ivory Coast). He has completed his Ph.D at the age of 33 years from Francois Rabelais University of Tours (France). He was the winner of Young Researcher Prize of SFR (French Society of Radiology) in 2010. He is associate Professor of Biophysics and Medical Imaging in Faculty of Health Science of University of Lomé, and the head of the Telemedicine and Radiation protection Unity of CHU Campus-Lomé. He has published more than 30 papers in reputed journals.

Abstract:

Objective: to review the level of knowledge and perception of the nuclear medicine by togolese physicians. Materials and Methods: Cross-sectional study conducted from 1st August to 30 September 2013 including 197 togolese general practitioners and specialists practicing in health facilities in Lomé, the capital of Togo. The level of physicians’ knowledge on the medical imaging technics used in nuclear medicine as well as their perception of nuclear medicine were analyzed. Results: Only 11.7% had completed an internship in apart from Togo. More than three quarters of physicians (83.8%) knew that nuclear medicine uses ionizing radiations. More than half (51.3%) disregarded that nuclear medicine is functional imaging and 61.4% thought it was more radiant than any other radiology examinations. Less than half of the physicians (47.2%) thought that the radiologist skills required to interpret a nuclear medicine examination. Only 22.8% and 3% physicians had respectively seen and prescribed nuclear medicine examination. They were 78.7% to estimate that the lack of nuclear medicine department in Togo hampers the management of patients and 68.5% to judge necessary its creation in Togo. More than half of the physicians (54.3%) wanted a radiotherapy department is created before a nuclear medical service. Conclusion: The level of knowledge of togolese physicians on nuclear medicine is acceptable and their perception of nuclear medicine is generally encouraging. Keyword: Nuclear Medicine, Medical Imaging, Togolese Physicians, Perception and level of knowledge, Medical Management. Knowledge and perception of Nuclear Medicine by Togolese physicians