Made available in DSpace on 2014-10-09T12:27:44Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:05:03Z (GMT). No. of bitstreams: 0 / Este trabalho apresenta um estudo exploratório do tipo transversal sobre a relação das doenças crônicas e o uso da tecnologia nuclear. O aumento na prevalência das doenças crônicas nos países em desenvolvimento é preocupante e devem ser avaliados cuidadosamente dentro das sociedades, organizações e seus indivíduos. Os avanços tecnológicos vivenciados nas últimas décadas, em especial, na área da tecnologia nuclear criam expectativas para lidar com o desafio das doenças de modo mais eficiente. Entretanto, pouco foi explorado sobre esse tema por um prisma dos agentes médicos que compõem esse sistema de relações entre a doença e a tecnologia. A necessidade de planejamentos públicos e privados para lidar com essa problemática podem se beneficiar de uma avaliação inicial sobre um tema ainda emergente, mas que deverá compor a agenda de planejamento em saúde e tecnologia nos próximos anos. Por meio de uma metodologia mista, composta por abordagem qualitativa e quantitativa buscou-se configurar e revelar as importantes dimensões sobre o tema dessa pesquisa. A pesquisa de campo foi composta tanto de entrevistas analisadas através de técnicas da teoria fundamentada e também de questionários enviados via web analisados estatisticamente através da análise fatorial exploratória. Tais empreendimentos permitiram revelar dimensões que compõem a percepção entre a doença crônica e o uso da tecnologia nuclear. Essas dimensões apresentadas na forma de um constructo teórico foram então discutidas de um ponto de vista da teoria social e de inovação tecnológica. / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Thesis (MScMedSc (Medical Imaging and Clinical Oncology. Nuclear Medicine))--University of Stellenbosch, 2010. / Thesis presented in partial fulfillment of the requirements for the degree of Master of Science in Nuclear Medicine at Stellenbosch University. / ENGLISH ABSTRACT: Introduction: There is conflicting data on the value of single photon emission tomography (SPECT) for the diagnosis of neuropsychiatric SLE (NPSLE). Visual assessment of brain SPECT scans is the standard approach in clinical practice. However the definition and identification of significant changes may be limited by a high interobserver variability, especially in centres with limited experience. This may be reduced by a more objective semi-quantitative assessment. The objectives of this study were to determine the sensitivity and specificity of SPECT for the detection of NPSLE at our institution using visual assesment, to determine the additional value of using an objective semi-quantitative diagnostic criterion, and to investigate the correlation between abnormal perfusion pattern and clinical NPSLE classification in patients with active NPSLE. Material and methods: Nineteen patients with NPSLE and 19 normal controls were studied with brain SPECT. Scans were interpreted blindly by two nuclear medicine physicians using two methods; visual and semi-quantitative assessments. In the visual method, overall visual impression was recorded for each scan using a four point scale, where A=normal, B=probably normal, C=probably abnormal, and D=abnormal. In addition, each brain region was assigned a severity score from 0=normal perfusion to 3=severe hypoperfusion. In the semi-quantitative assessment, ten-band color scale was used, and perfusion deficit was quantified on the side with the lower color intensity comparing to the contralateral side. A score was given to the region with perfusion deficit according to the difference (in color bands) between the two hemispheres. Analysis was performed for the visual assessment method (overall impression and severity scores) and the semi-quantitative assessment method using a receiver operator characteristic (ROC) curve. Optimal cut-off points were determined and the accuracy of the different techniques was also compared statistically. Finally, the correlation was determined between the SPECT perfusion pattern and the clinical pattern of disease. Results: An ROC curve analysis for the overall visual impression resulted in an area under the curve of 0.76. At a cut-off point of C (probably abnormal), brain SPECT had 89% sensitivity and 57% specificity for the diagnosis of NPSLE. The severity score which include the total severity score and the modified total severity score resulted in areas under the curve of 0.75 and 0.79 respectively. The semi-quantitative assessment resulted in areas under the ROC curve of 0.80. Statistically, there was no difference between the overall visual impression, visual severity scores, and the semi-quantitative assessment. Agreement analysis between the SPECT pattern and clinical pattern of disease showed agreement in 91.6% in the diffuse pattern, whereas agreement in the focal pattern was seen in only 42.8%. Discussion and Conclusion: In this study, we found that brain SPECT is able to diagnose active NPSLE with a high sensitivity and moderate specificity. The overall visual impression, visual severity scores, and the semi-quantitative assessment showed no significant differences between the techniques. The use of the semi-quantitative assessment described may be useful in centers with limited experience in the interpretation of brain SPECT. The correlation between the SPECT pattern and clinical disease pattern may provide some insights into the pathophysiology of NPSLE. / AFRIKAANSE OPSOMMING: Inleiding: Daar is teenstrydige inligting oor die waarde van brein enkelfoton emissie tomografie (EFET) vir die diagnose van neuropsigiatriese SLE (NPSLE). Visuele beoordeling van brein EFET flikkergramme is die standaard benadering in kliniese praktyk. Die definisie en identifisering van betekenisvolle veranderinge mag egter beperk word deur 'n hoë inte-waarnemer wisseling, veral in sentra met beperkte ondervinding. Dit mag verminder word deur 'n meer objektiewe semi-kwantitatiewe beoordeling. Die doel van hierdie studie was om 1. Die sensitiwiteit en spesifisiteit van EFET vir die opspoor van NPSLE in ons instelling te bepaal, 2. Die bykomende waarde van 'n objektiewe semi-kwantitatiewe diagnostiese kriterium vas te stel, en 3. Die korrelasie tussen 'n abnormale perfusiepatroon en 'n kliniese NPSLE klassifikasie in pasiënte met aktiewe NPSLE te ondersoek. Materiaal en Metodes: Negentien pasiënte met NPSLE en 19 normale kontroles is met brein EFET bestudeer. Flikkergramme is blind deur twee kerngeneeskundiges geïnterpreteer, deur gebruik te maak van twee metodes, 'n visuele en semi-kwantitatiewe beoordeling. Vir elke flikkergram is 'n globale visuele indruk genoteer deur gebruik te maak van 'n 4-punt skaal, waar A=normaal, B=waarskynlik normaal, C= waarskynlik abnormaal, en D=abnormaal. Bykomend is 'n ernstigheidsgraad waarde van 0=normale perfusie tot 3=erge hipoperfusie vir elke breinstreek toegeken. Vir die semi-kwantitatiewe beoordeling is 'n telling vir streke met laer intensiteit vergeleke met die kontralaterale kant toegeken, volgens die verskille in kleurbande deur gebruik te maak van 'n tienbandskaal. Die visuele metodes vir die globale indruk, visuele ernstigheidsgraad waarde, en die semi-kwantitatiewe beoordeling is geanaliseer deur 'n relatiewe funksioneringskenmerk (receiver operator characteristic (ROC)) kurwe te gebruik en optimale afsnypunte te bepaal. Die akkuraatheid van die verskillende tegnieke is ook statisties vergelyk. Laastens is die korrelasie tussen die EFET perfusiepatroon en die kliniese siektepatroon bepaal. Resultate: 'n ROC kurwe analise vir die globale visuele indruk het gelei tot 'n area onder die kurwe van 0.77. By 'n afsnypunt van (C) het brein EFET 'n sensitiwiteit van 89% en 'n spesifisiteit van 57% vir die diagnose van NPSLE gehad. Die visuele ernstigheidsgraad telling, en die semi-kwantitatiewe beoordeling het onderskeidelik tot areas onder die ROC kurwe van 0.75 en 0.79 vir die visuele ernstigheidsgraad waarde, en 0.8 vir die semi-kwantitatiewe beoordeling gelei. Statisties was daar geen verskil tussen die globale visuele indruk, die visuele ernstigheidsgraad waarde, en die semi-kwantitatiewe beoordeling nie. Ooreenstemmingsanalise tussen die EFET patroon en kliniese siektepatrone het 'n ooreenstemming van 91.6% in die diffuse patroon getoon, terwyl die fokale patroon ooreenstemming van slegs 42.8% getoon het. Bespreking en Gevolgtrekkig: In hierdie studie is gevind dat brein EFET 'n diagnose van NPSLE kan maak met 'n hoë sensitiwiteit en gemiddelde spesifisiteit. Die globale visuele indruk, visuele ernstigheidsgraad waarde, en die semi-kwantitatiewe beoordeling wat beskryf is, het geen betekenisvolle verskille tussen die tegnieke getoon nie. Die gebruik van die semi-kwantitatiewe beoordeling wat beskryf is, mag van waarde wees in sentra met beperkte ondervinding in the interpretasie van brein EFET. Die korrelasie tussen die EFET patroon en kliniese siektepatrone mag insig gee in die patofisiologie van NPSLE.

No description available.

Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.

The Biomedical Imaging Lab at the University of Manitoba is building an MR compatible PET insert system. The detectors include SensL SPM ArraySB-4 SiPMs and dual layer offset LYSO crystal blocks with 409 total crystals. The detectors’ gain varies with temperature and bias voltage. Measurements inside the MR magnet revealed that the equilibrium temperature was around 30°C. The photopeak amplitude, energy resolution and events per crystal were studied at 30°C and also at temperatures from 20°C to 40°C with a fixed overvoltage of 2.5V and with a fixed bias voltage of 27.95V. It was determined that a fixed overvoltage helps stabilize detector output but is not sufficient. A study of detector characteristics versus overvoltage was subsequently conducted and a lookup table was constructed to adjust bias voltage. A distributed network-based control system was developed in this thesis project to monitor the operating parameters of the detectors.

Thesis--University of Oklahoma. / Bibliography: leaves 92-93.

Thesis (MSc)--Stellenbosch University, 2005. / ENGLISH ABSTRACT: Introduction: Quality assurance in Nuclear Medicine is of utmost importance in order to ensure optimal scintigraphic results and correct patient management. A customised Quality Management System (QMS) should be documented and implemented by following the international guidelines set by the International Standardisation Organization (ISO). Materials & Methods: A Quality Control Manual (QCM), defining the departmental quality policy, mission, vision and objectives was customised following the framework of a tried and tested design. As ISO focuses on client satisfaction and staff harmony, the following departmental objectives were audited in working towards the accreditation of the Nuclear Medicine Department of Tygerberg Hospital: referring physician satisfaction, patient satisfaction as well as staff satisfaction and harmony. Information was collected by means of questionnaires completed by referring physicians and staff members. One-on-one interviews were executed on patients. An international ISO accredited Nuclear Medicine department was visited to establish the suggested path to follow en route to successful ISO accreditation and certification. Results: Referring physicians indicated overall satisfaction with service provision, but a need for electronic report and image transfers seemed too dominant. The patient satisfaction survey resulted into overall satisfaction with personal service providing, but the provision of written and understandable information, long waiting times and t equipment must receive attention. Staff questionnaires indicated a general lack of communication between different professional groups and the need for interpersonal loyalty and team building. Improvement measures were identified to ensure the continuous improvement of the QMS by focusing on these quality parameters. Conclusion: The department has QA procedures in place, but does not meet all criteria for external accreditation. In order to ensure departmental harmony and sustainability of client and staff satisfaction, the departmental objectives in measured and improved where needed. The successful implementation and continuous improvement of a customised QMS, following the guidelines outlined in the QCM will lead to successful accreditation. / AFRIKAANSE OPSOMMING: Inleiding: Die belangrikheid van kwaliteit versekering in Kerngeneeskunde vir die versekering van optimale flikkergrafiese resultate en korrekte pasient handtering kan nie onderskat word me. 'n Klantgerigte Kwaliteitsbeheersisteem (KBS) moet gedokumenteer en geimplimenteer word vir die Kerngeneeskunde Departement deur die riglyne te volg soos uiteengesit deur die Internationale Standardiserings Organisasie (ISO). Materiale & Metodes: 'n Kwaliteitskontrol handleiding (KB), wat die departementele kwaliteitsbeleid, die missie en visie asook die departementele doelwitte definieer is ontwerp en saamgestel vir die Kerngeneeskunde departement van Tygerberg Hospitaal. Hierdie ontwerp is gebaseer op die raamwerk van 'n aanvaarde kwalteitsbeheersisteem. ISO fokus op klante tevredenheid asook personeel harmonie en tevredenheid. Vir hierdie rede is daar 'n tevredenheidpeiling uitgevoer op die klante en personeel in die strewe na ISO akkreditasie en sertifikasie. Inligting was versamel deur vraelyste wat ingevul was deur die verwysende geneeshere, pasiente en personeel. Resultate: 'n Kwaliteitskontrole handleiding was saamgestel VIr gebruik in die Kerngeneeskunde department. Die interne audit resultate het aangedui dat die verwysende geneeshere tevrede is met die algehele dienslewering. Die behoefde aan elektronies versende verlae en beelde was dominerend. Die pasient tevredenheidspeiling het bevestig dat die pasiente tevrede is met persoonlike dienslewering, maar 'n tekort aan verstaanbare en geskrewe inligting was geidentifiseer. Die lang wagtye en stukkende apparaat is ook gebiede wat verbertering benodig. Algemene gebrek aan komminukasie tussen die verskillende beroepsgroepe, die behoefte aan interpersoonlike lojaliteit en span werk was die hoof bevindinge van die personeel tevredenheidspeiling. Verbeterings maatreels, gefokus op hierdie departementele doelwitte, was geidentifiseer ten eide te verseker dat die KBS voordurend verbeter en in stand gehou word. Samevatting: Alhoewel die departement wel KB prosedures in plek het, voldoen dit nie aan al die criteria vir eksterne akkreditasie nie. Ten einde departementele harmonie en kliente tevredenheid te verseker, met die oog op ISO sertifikasie, moet die departmenteIe doelwitte deurlopend gemeet en verbeter word.

Imaging in nuclear medicine involves the injection of a radioactive tracer into the body and subsequent detection of the radiation emanating from an organ of interest. Single-photon emission computed tomography (SPECT) is the branch of nuclear medicine that yields three-dimensional maps of the distribution of a tracer, most commonly as a series of two-dimensional slices. One major drawback to transaxial tomographic imaging in SPECT today is the rotation required of a gamma camera to collect the tomographic data set. Transaxial SPECT usually involves a large, single-crystal scintillation camera and an aperture (collimator) that together only satisfy a small portion of the spatial sampling requirements simultaneously. It would be very desirable to have a stationary data-collection apparatus that allows all spatial sampling in the data set to occur simultaneously. Aperture or detector motion (or both) is merely an inconvenience in most imaging situations where the patient is stationary. However, aperture or detector motion (or both) enormously complicate the prospect of tomograhically recording dynamic events, such as the beating heart, with radioactive pharmaceuticals. By substituting a set of small modular detectors for the large single-crystal detector, we can arrange the usable detector area in such a way as to collect all spatial samples simultaneously. The modular detectors allow for the possibility of using other types of stationary apertures. We demonstrate the capabilities of one such aperture, the pinhole array. The pinhole array is one of many kinds of collimators known as coded apertures. Coded apertures differ from conventional apertures in nuclear medicine in that they allow for overlapping projections of the object on the detector. Although overlapping projections is not a requirement when using pinhole arrays, there are potential benefits in terms of collection efficiency. There are also potential drawbacks in terms of the position uncertainty of emissions in the reconstruction object. The long-term goal of the research presented is dynamic SPECT imaging of the heart. The basic concepts and tasks involved in transaxial SPECT imaging with pinhole arrays are presented along with arguments for the combination of modular gamma cameras and pinhole arrays. We demonstrate by emulation two methods of tomographically imaging a stationary single object slice and present results for these two systems on object space grids of 10cm x 10cm and 20cm x 20cm.

No description available.