Lim W, Ahmad Sarji S, Yik Y
… +1 more, Ramanujam T
Biomed Imaging Interv J
· 2008 Jan · PMID 21614318
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This case describes the radiological-surgical correlation of a rare case of osteosarcoma of the rib in a 15-year-old boy. Successful repair of his chest wall defect using a wire mesh following extensive surgical resectio...This case describes the radiological-surgical correlation of a rare case of osteosarcoma of the rib in a 15-year-old boy. Successful repair of his chest wall defect using a wire mesh following extensive surgical resection of the tumour is highlighted, such a procedure being the first instituted at our centre.
Rehani B, Dowdy Y, Bharija A
… +1 more, Strohmeyer P
Biomed Imaging Interv J
· 2008 Jan · PMID 21614317
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FDG-PET/CT is a widely established imaging modality for staging, restaging and monitoring therapy response in lymphoma patients. Progressive transformation of germinal centres (PTGC) is a benign condition presenting char...FDG-PET/CT is a widely established imaging modality for staging, restaging and monitoring therapy response in lymphoma patients. Progressive transformation of germinal centres (PTGC) is a benign condition presenting characteristically as asymptomatic lymphadenopathy. This paper presents a case of a 53-year-old man with a history of Hodgkin's disease (HD) whose F(18) FDG-PET/CT scan showed high uptake in left axillary lymph nodes (SUV 3.8). A subsequent, left axillary lymph node biopsy revealed PTGC. PTGC can present as a false positive finding on FDG-PET/CT in lymphoma patients and biopsy should be done in HD patients in clinical remission but have a positive FDG-PET/CT scan.
Biomed Imaging Interv J
· 2008 Jan · PMID 21614316
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Good Clinical Practice (GCP) is an international ethical and scientific quality standard for the design, conduct, performance, monitoring, auditing, recording, analyses and reporting of clinical trials. It also serves to...Good Clinical Practice (GCP) is an international ethical and scientific quality standard for the design, conduct, performance, monitoring, auditing, recording, analyses and reporting of clinical trials. It also serves to protect the rights, integrity and confidentiality of trial subjects. It is very important to understand the background of the formation of the ICH-GCP guidelines as this, in itself, explains the reasons and the need for doing so. In this paper, we address the historical background and the events that led up to the formation of these guidelines. Today, the ICH-GCP guidelines are used in clinical trials throughout the globe with the main aim of protecting and preserving human rights.
Suriyapee S, Pitaxtarnin N, Oonsiri S
… +2 more, Jumpangern C, Israngkul Na Ayuthaya I
Biomed Imaging Interv J
· 2008 Jan · PMID 21614315
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PURPOSE: To investigate the optimal sensitometric curves of extended dose range (EDR2) radiographic film in terms of depth, field size, dose range and processing conditions for dynamic intensity modulated radiation thera...PURPOSE: To investigate the optimal sensitometric curves of extended dose range (EDR2) radiographic film in terms of depth, field size, dose range and processing conditions for dynamic intensity modulated radiation therapy (IMRT) dosimetry verification with 6 MV X-ray beams. MATERIALS AND METHODS: A Varian Clinac 23 EX linear accelerator with 6 MV X-ray beam was used to study the response of Kodak EDR2 film. Measurements were performed at depths of 5, 10 and 15 cm in MedTec virtual water phantom and with field sizes of 2x2, 3x3, 10x10 and 15x15 cm(2). Doses ranging from 20 to 450 cGy were used. The film was developed with the Kodak RP X-OMAT Model M6B automatic film processor. Film response was measured with the Vidar model VXR-16 scanner. Sensitometric curves were applied to the dose profiles measured with film at 5 cm in the virtual water phantom with field sizes of 2x2 and 10x10 cm(2) and compared with ion chamber data. Scanditronix/Wellhofer OmniPro(TM) IMRT software was used for the evaluation of the IMRT plan calculated by Eclipse treatment planning. RESULTS: Investigation of the reproducibility and accuracy of the film responses, which depend mainly on the film processor, was carried out by irradiating one film nine times with doses of 20 to 450 cGy. A maximum standard deviation of 4.9% was found which decreased to 1.9% for doses between 20 and 200 cGy. The sensitometric curves for various field sizes at fixed depth showed a maximum difference of 4.2% between 2x2 and 15x15 cm(2) at 5 cm depth with a dose of 450 cGy. The shallow depth tended to show a greater effect of field size responses than the deeper depths. The sensitometric curves for various depths at fixed field size showed slightly different film responses; the difference due to depth was within 1.8% for all field sizes studied. Both field size and depth effect were reduced when the doses were lower than 450 cGy. The difference was within 2.5% in the dose range from 20 to 300 cGy for all field sizes and depths studied. Dose profiles measured with EDR2 film were consistent with those measured with an ion chamber. The optimal sensitometric curve was acquired by irradiating film at a depth of 5 cm with doses ranging from 20 to 450 cGy with a 3×3 cm(2) multileaf collimator. The optimal sensitometric curve allowed accurate determination of the absolute dose distribution. In almost 200 cases of dynamic IMRT plan verification with EDR2 film, the difference between measured and calculated dose was generally less than 3% and with 3 mm distance to agreement when using gamma value verification. CONCLUSION: EDR2 film can be used for accurate verification of composite isodose distributions of dynamic IMRT when the optimal sensitometric curve has been established.
Biomed Imaging Interv J
· 2008 Jan · PMID 21614314
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Glioblastoma multiforme (GBM) is the most aggressive form of primary brain tumours known collectively as gliomas. Gliomas are graded by their microscopic appearance. As a rule, their behaviour can be predicted from histo...Glioblastoma multiforme (GBM) is the most aggressive form of primary brain tumours known collectively as gliomas. Gliomas are graded by their microscopic appearance. As a rule, their behaviour can be predicted from histology: Grade I (pilocytic astrocytomas) and Grade II (benign astrocytomas) tumours are of low grade and grow slowly over many years. Grade IV tumours (GBM) are the most aggressive and, unfortunately, also the most common in humans, growing rapidly, invading and altering brain function. These tumours arise from the supporting glial cells of the brain during childhood and in adulthood.These growths do not spread throughout the body like other forms of cancer, but cause symptoms by invading the brain. Untreated GBMs are rapidly lethal. Most patients with GBM die of their disease in less than a year and none have long term survival.Extracranial metastases from GBM are extremely rare, with a reported frequency of only 0.44% because of the absence of lymphatics in the brain and the difficulty of tumours to penetrate blood vessels. A case of glioblastoma multiforme with the rare features of extensive liver and bone metastases is presented in this paper.
Biomed Imaging Interv J
· 2008 Jan · PMID 21614313
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Medical physics has been identified as one of the key areas that need to be developed to improve healthcare. However, the level achieved in developing countries represents a stark contrast to the level that exists in Wes...Medical physics has been identified as one of the key areas that need to be developed to improve healthcare. However, the level achieved in developing countries represents a stark contrast to the level that exists in Western Europe or North America. The challenge for developing countries is to build the required infrastructures, to acquire the equipment, to attract highly qualified professionals and to develop education and training programs and political policies for effective and accessible care within budgetary constraints. The state-of-the-art technological developments in medical physics cannot be viewed as a uniform reality all over the world. There is, of course, a wide difference in emphasis and approach when dealing with developing countries, compared to developed nations. As quality assurance and cost-benefit guidelines in the practice of radiation therapy and diagnostic imaging are being developed and debated in developed countries, the perspectives of the availability and standards of healthcare taken for granted in these countries stand in stark contrast to the level administered in developing countries. In this contribution, the overall situation of medical physics in developing countries and the barriers to improvement are discussed, and some possible solutions and ways to bridge the gap between developed and developing countries are suggested.
Biomed Imaging Interv J
· 2008 Jan · PMID 21614312
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Medical Physics and Engineering was among the first professions to develop and apply e-Learning (e-L). The profession provides excellent background for application of simulations and other e-L materials. The paper descri...Medical Physics and Engineering was among the first professions to develop and apply e-Learning (e-L). The profession provides excellent background for application of simulations and other e-L materials. The paper describes several layers for e-L development: Programming specific simulations; Building e-L modules; Development of e-L web-based programmes. The paper shows examples from these layers and outlines their specificities. At the end, the newest e-L development (project EMITEL) is briefly introduced and the necessity of a regularly updated list of e-L activities is emphasised.
Biomed Imaging Interv J
· 2008 Jan · PMID 21614310
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Postgraduate medical education and training in many specialties, including Clinical Radiology, is undergoing major changes. In part this is to ensure that shorter training periods maximise the learning opportunities but...Postgraduate medical education and training in many specialties, including Clinical Radiology, is undergoing major changes. In part this is to ensure that shorter training periods maximise the learning opportunities but it is also to bring medical education in line with broader educational theory. Learning outcomes need to be defined so that there is no doubt what knowledge, skills, attitudes and behaviours are expected of those in training. Curricula should be developed into competency or outcome based models and should state the aims, objectives, content, outcomes and processes of a training programme. They should include a description of the methods of learning, teaching, feedback and supervision. Assessment systems must be matched to the curriculum and must be fair, reliable and valid. Workplace based assessments including the use of multisource feedback need to be developed and validated for use during radiology training. These should be used in a formative and developmental way, although the overall results from a series of such assessments can be used in a more summative way to determine progress to the next phase of training. Formal standard setting processes need to be established for 'high stakes' summative assessments such as examinations. In addition the unique skills required of a radiologist in terms of image interpretation, pattern recognition, deduction and diagnosis need to be evaluated in robust, reliable and valid ways. Through a combination of these methods we can be assured that decisions about trainees' progression through training is fair and standardised and that we are protecting patients by establishing national standards for training, curricula and assessment methods.
Biomed Imaging Interv J
· 2008 Jan · PMID 21614309
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There is a significant need for high-quality medical physics education and training in all countries to support effective and safe use of modern medical technology for both diagnostic and treatment purposes. This is, and...There is a significant need for high-quality medical physics education and training in all countries to support effective and safe use of modern medical technology for both diagnostic and treatment purposes. This is, and will continue to be, achieved using appropriate technology to increase both the effectiveness and efficiency of educational activities everywhere in the world. While the applications of technology to education and training are relatively new, the successful applications are based on theories and principles of the learning process developed by two pioneers in the field, Robert Gagne and Edgar Dale.The work of Gagne defines the different levels of learning that can occur and is used to show the types and levels of learning that are required for the application of physics and engineering principles to achieve appropriate diagnostic and therapeutic results from modern technology. The learning outcomes are determined by the effectiveness of the learning activity or experience. The extensive work of Dale as formulated in his Cone of Experience relates the effectiveness to the efficiency of educational activities. A major challenge in education is the development and conduction of learning activities (classroom discussions, laboratory and applied experiences, individual study, etc) that provide an optimum balance between effectiveness and efficiency. New and evolving models of the educational process use technology as the infrastructure to support education that is both more effective and efficient.The goal is to use technology to enhance human performance for both learners (students) and learning facilitators (teachers). A major contribution to global education is the trend in the development of shared educational resources. Two models of programs to support this effort with open and free shared resources are Physical Principles of Medical Imaging Online (http://www.sprawls.org/resources) and AAPM Continuing Education Courses (http://www.aapm.org/international).
Moratal D, Vallés-Luch A, Martí-Bonmatí L
… +1 more, Brummer M
Biomed Imaging Interv J
· 2008 Jan · PMID 21614308
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A main difference between Magnetic Resonance (MR) imaging and other medical imaging modalities is the control over the data acquisition and how it can be managed to finally show the adequate reconstructed image. With som...A main difference between Magnetic Resonance (MR) imaging and other medical imaging modalities is the control over the data acquisition and how it can be managed to finally show the adequate reconstructed image. With some basic programming adjustments, the user can modify the spatial resolution, field of view (FOV), image contrast, acquisition velocity, artifacts and so many other parameters that will contribute to form the final image. The main character and agent of all this control is called k-space, which represents the matrix where the MR data will be stored previously to a Fourier transformation to obtain the desired image.This work introduces 'k-Space tutorial', a MATLAB-based educational environment to learn how the image and the k-space are related, and how the image can be affected through k-space modifications. This MR imaging educational environment has learning facilities on the basic acceleration strategies that can be encountered in almost all MR scanners: scan percentage, rectangular FOV and partial Fourier imaging. It also permits one to apply low- and high-pass filtering to the k-space, and to observe how the contrast or the details are selected in the reconstructed image. It also allows one to modify the signal-to-noise ratio of the acquisition and create some artifacts on the image as a simulated movement of the patient - with variable intensity level - and some electromagnetic spikes on k-space occurring during data acquisition.
Biomed Imaging Interv J
· 2008 Jan · PMID 21614307
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Patients expect to receive safe, predictable and high-quality care delivered by competent professionals. Thus, it has become important to provide specific training in existing and new modalities and prove on-going clinic...Patients expect to receive safe, predictable and high-quality care delivered by competent professionals. Thus, it has become important to provide specific training in existing and new modalities and prove on-going clinical expertise. Hospital credentialing is the process by which the competence of a doctor is determined by the hospital management. In Australia, radiologists participate in a mandatory program of continuing professional development and are also required to maintain a logbook of procedures. The Conjoint Committee for the Recognition of Training in Peripheral Endovascular Therapy has been established to advise the respective subspecialty groups on the requirements for accreditation. This article examines some of the issues the committee has considered in preparing the criteria to assist institutions for the purposes of credentialing and gives an Australian perspective on future trends.
Biomed Imaging Interv J
· 2008 Jan · PMID 21614306
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Medical physics is a relatively small professional community, usually with a scarcity of expertise that could greatly benefit students entering the field. However, the reach of the profession can span great geographical...Medical physics is a relatively small professional community, usually with a scarcity of expertise that could greatly benefit students entering the field. However, the reach of the profession can span great geographical distances, making the training of students a difficult task. In addition to the requirement of training new students, the evolving field of medical physics, with its many emerging advanced techniques and technologies, could benefit greatly from ongoing continuing education as well as consultation with experts.Many continuing education courses and workshops are constantly being offered, including many web-based study courses and virtual libraries. However, one mode of education and communication that has not been widely used is the real-time interactive process. Video-based conferencing systems do exist, but these usually require a substantial amount of effort and cost to set up.The authors have been working on promoting the ever-expanding capability of the Internet to facilitate the education of medical physics to students entering the field. A pilot project has been carried out for six years and reported previously. The project is a collaboration between the Department of Medical Physics at the Toronto Odette Cancer Centre in Canada and the Department of Biomedical Imaging at the University of Malaya in Malaysia. Since 2001, medical physics graduate students at the University of Malaya have been taught by lecturers from Toronto every year, using the Internet as the main tool of communication.The pilot study explored the different methods that can be used to provide real-time interactive remote education, and delivered traditional classroom lectures as well as hands-on workshops.Another similar project was started in 2007 to offer real-time teaching to a class of medical physics students at Wuhan University in Hubei, China. There are new challenges as well as new opportunities associated with this project. By building an inventory of tools and experiences, the intent is to broaden the real-time teleteaching method to serve a wide community so that future students entering the field can have efficient access to high-quality education that will benefit the profession in the long term.
Baboi L, Milot L, Lartizien C
… +4 more, Roche C, Scoazec JY, Pilleul F, Beuf O
Biomed Imaging Interv J
· 2007 Oct · PMID 21614301
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AIM: The objective of this work was to propose original synchronisation strategies based on T2-weighted sequence performed on a small animal MRI spectrometer in order to improve the image contrast and detect mouse liver...AIM: The objective of this work was to propose original synchronisation strategies based on T2-weighted sequence performed on a small animal MRI spectrometer in order to improve the image contrast and detect mouse liver lesions at high magnetic field. MATERIALS AND METHODS: The experiments were performed in vivo at 7T using a 32 mm inner diameter cylindrical volumetric coil for both RF emission and reception. A sensitive pressure sensor was used to detect external movements due to both respiration and heart beats. The pressure sensor was interfaced with a commercial ECG Trigger Unit to use dedicated functionalities (trigger levels, delays and window). To enable T2-weighted imaging with minimised T1 effects, an acquisition strategy with controlled TR spanning over several respiratory cycles was developed. With this strategy, the slices were acquired over several respiratory periods. RESULTS: The acquisition, performed over several respiratory periods, enables a longer TR than the typical mouse respiratory period. The image contrast is controllable and independent of the respiratory period. The heavily T2-weighted images obtained with the developed strategy allow better visualisation of lesions at high magnetic field. Moreover, double respiratory and cardiac synchronisation, based on a unique sensitive pressure sensor, improves image quality with less motion artifacts, especially in the ventral liver region. The total slice number is independent of respiratory period and thin slices can be acquired to cover the whole liver. CONCLUSION: The developed strategy enables high quality pure T2-weighted imaging with minimal motion artifacts. This strategy improves T2-weighted image contrast and quality, especially at high magnetic field, on animals with short respiratory periods. The strategy was demonstrated using a mouse model of liver lesions at 7T. This protocol could be used to carry out a longitudinal follow-up.
Biomed Imaging Interv J
· 2007 Oct · PMID 21614300
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Primary bone lymphoma is an uncommon tumour accounting for approximately 4-5% of extra nodal lymphoma and less than 1% of all Non-Hodgkin's lymphoma. The radiographic appearance of primary bone lymphoma is variable. As l...Primary bone lymphoma is an uncommon tumour accounting for approximately 4-5% of extra nodal lymphoma and less than 1% of all Non-Hodgkin's lymphoma. The radiographic appearance of primary bone lymphoma is variable. As lesions frequently resemble other disease processes namely chronic osteomyelitis and metastases, further imaging evaluation and histopathological examination allow early identification for appropriate treatment. The authors present a case of anaplastic large cell lymphoma of bone presenting with multifocal osseus involvement.
Biomed Imaging Interv J
· 2007 Oct · PMID 21614299
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The common presentations of lymphoma are widespread lymphadenopathy or development of constitutional symptoms. This paper presents a case of a patient who presented with a solitary mass detected on chest X-ray and underw...The common presentations of lymphoma are widespread lymphadenopathy or development of constitutional symptoms. This paper presents a case of a patient who presented with a solitary mass detected on chest X-ray and underwent FDG-PET for further evaluation of this mass. FDG-PET is a commonly utilised technique to assess solitary nodules as it not only allows characterisation of the lesion but can also detect nodal and extra-thoracic disease with greater accuracy than the standard CT. In this case, FDG-PET demonstrated abnormal activity in the lung nodule and at the gastro-oesophageal junction. Biopsies confirmed Non-Hodgkin's Lymphoma at both sites. The value of FDG-PET in this case was the determination of previous unsuspected disease in an unusual presentation of lymphoma and as a useful tool for monitoring the therapeutic effect post chemotherapy.