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Embora a avaliação da viabilidade miocárdica seja comum na prática do cardiologista, muitos médicos têm dúvidas a respeito dos resultados dos métodos diagnósticos. A medicina nuclear tem papel importante nos estudos de viabilidade, mas os laudos precisam ser interpretados num contexto clínico e fisiopatológico. Este artigo teve o objetivo de revisar a origem e a evolução do conceito da viabilidade miocárdica. São expostos os métodos diagnósticos com ênfase na medicina nuclear com uma explicação funcional sobre cada tipo de exame. A partir disso, são mostradas imagens como exemplos e é proposta uma maneira de atuar nesses casos baseada na clínica, na porcentagem de miocárdio acometido e na topografia das lesões coronarianas (proximais ou distais). (AU)

Although assessing myocardial viability is a common cardiology practice, many physicians question the results of diagnostic methods. Nuclear medicine plays an important role in viability studies, but the reports require interpretation in a clinical and pathophysiological context. this article was aimed at reviewing the origin and evolution of myocardial viability. Here we present diagnostic methods by emphasizing nuclear medicine and provide a functional explanation of each test type using example images. We also propose how to act in these cases based on clinic examination findings, the percentage of affected myocardium, and coronary lesion topography (proximal or distal).(AU)

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Esta es una nueva edición del libro Control de calidad de la instrumentación en medicina nuclear: protocolo nacional es una actualización de la edición anterior, teniendo en cuenta la experiencia nacional e internacional alcanzadaen en este campo e introduciendo nuevas pruebas para el control de calidad de los epuipos multimodades como tomografía por emisión de positrones/tomografía computarizada y tomografía de emisión de fotón único/tomografía computarizada. Constituye una referencia técnica detallada para las pruebas de aceptación y para la elaboración de los programas de control de calidad de la instrumentación nuclear, disponible en cada servicio de medicina nuclear, en correspondencia con las recomendaciones internacionales.

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Se realizó un estudio descriptivo, longitudinal y transversal que incluyó a los pacientes operados de neoplasia del sistema nervioso central intracraneal en el Hospital General Docente Abel Santamaría Cuadrado de la provincia Pinar del Río, durante el período comprendido desde el 1 de enero de 2010 hasta el 31 de diciembre del mismo año. Se incluyeron todos los pacientes egresados a los que se les había realizado tomografía computarizada o resonancia magnética y poseían diagnóstico histológico posoperatorio de neoplasia primaria del sistema nervioso central (SNC) intracraneal. Se concluyó que las neoplasias primarias fueron más frecuentes en el sexo femenino y en grupo de edad de 70 años y más. Las localizaciones más frecuentes de las neoplasias primarias del sistema nervioso central fueron las masas intraaxiales y supratentoriales y el tipo histológico más prevalente fue el glioma. Todas se comportaron imagenológicamente captantes de contraste, con poca hemorragia y calcificación intermediamente con efecto de masa y hipointensas en T1 hiperintensas en T2(AU)

A descriptive, longitudinal and cross-sectional study including the patients operated on intracranial central nervous system neoplasm was carried out at Abel Santamaria Cuadrado University Hospital, Pinar del Rio during January 1, 2010 to December 31, 2010. All patients discharged from the hospital with Computerized Axial Tomography or Magnetic Resonance Imaging and having post-operative histological diagnosis of primary intracranial neoplasm of the central nervous system (CNS) were included. Primary neoplasm was the most frequent in female sex and in the age-bracket of 70 years old or older. The most repeated localizations of primary neoplasm in the CNS were in intra-axial and supratentorial masses, glioma was the most prevailing histological type. Contrast examinations could be performed in all masses, presenting not much hemorrhage, with intermediate-mass-effect calcifications and hypo-intensive in T1 and hyper-intensive in T2(AU)

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La Medicina Nuclear es una de las áreas de la Radiología que estudia al organismo dinámicamente, emplea radiofármacos y detectores externos para la obtención de la imagen, su eficacia diagnóstica depende en gran medida de la precisión con la que el Activímetro mide la actividad de un radiofármaco, lo cual está garantizado por el control de calidad diario, particularmente, mediante el cálculo de la exactitud. Por lo anterior, el objetivo general de la presente investigación es determinar el nivel de coincidencia del cálculo de exactitud teórica y práctica del Activímetro marca CAPINTEC modelo CRC-15 del centro diagnóstico PET SCAN PERU. Para el presente estudio, se recopilaron un total de 306 datos, obtenidos mediante cuadros de trabajo virtuales redactados en formatos Word y Excel para recolectar los datos de exactitud teórica y práctica del Cesio137 y Cobalto57 por cada mes a partir de Mayo de 2010 a diciembre de 2011, los cuales cumplieron con los criterios de inclusión y exclusión establecidos. De éstos, 153 (50 por ciento) fueron de Cesio137 y 153 (50 por ciento) fueron de Cobalto57. El 100 por ciento de los datos de radiación de fondo estuvieron dentro de los valores normales. Mediante la prueba estadística T de Student se demostró que existe semejanza entre los datos de exactitud teórica y práctica. Con la prueba Correlación de Pearson (R) se demostró que el nivel de coincidencia del cálculo de la exactitud teórica y práctica fue alto (95 por ciento). Sin embargo, para el Cobalto57 en el mes de agosto 2010 (0.0632) y para el Cesio137 el mes de junio de 2011 (0.158), hubo un bajo nivel de coincidencia (5 por ciento)

Nuclear medicine is one of the areas of radiology that studies the body dynamically, radiopharmaceuticals and external detectors used to obtain the image; its diagnostic efficacy depends largely on the exactness which the Activimeter measures the radiopharmaceutical activity. This is guaranteed by the daily quality control, exactly by calculating accuracy. Therefore, the overall objective of this research is to determine the level of matching accuracy of the calculation of theoretical and practical Activimeter CAPINTEC CRC-15, in the Diagnostic Center PET SCAN PERU. For the present study were collected a total of 306 data, obtained by virtual work tables written in Word and Excel to collect data on theoretical and practical accuracy of Cesio137 and Cobalto57 per month from May 2010 to December 2011, which met the inclusion criteria and exclusion set. Of these, 153 (50 per cent) were Cesio137 and 153 (50 per cent) were Cobalto57. 100 per cent of the background radiation data were within normal values. By means of the statistical test T de Student demonstrated that similarity exists between the information of theoretical and practical accuracy. With the test Pearson's Correlation (R) demonstrated that the level of coincidence of the calculation of the theoretical and practical accuracy was high (95 per cent). Nevertheless, for the Cobalto57 in August, 2010 (0.0632) and for the Cesio137 June, 2011 (0.158), there was a low level of coincidence (5 per cent)

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Several methods can be used to determine the activity of (131)I in the treatment of hyperthyroidism. However, many of them do not consider all the parameters necessary for optimum dose calculation. The relationship between the dose absorbed by the thyroid and the activity administered depends basically on three parameters: organ mass, iodine uptake and effective half-life of iodine in the thyroid. Such parameters should be individually determined for each patient in order to optimize the administered activity. The objective of this work is to develop a methodology for individualized treatment with (131)I in patients with hyperthyroidism of the Grave's Disease. A neck-thyroid phantom developed at the IRD was used to calibrate a scintillation camera and a uptake probe SCT-13004 at the Nuclear Medicine Center of the University Hospital of Rio de Janeiro and a uptake probe SCT-13002, available at the Nuclear Medicine Institute in Goiânia. The biokinetic parameters were determined based on measurements performed in eight voluntary patients. It is concluded that the use of the equipment available at the hospital (scintillation camera and uptake probe) has shown to be a suitable and feasible procedure for dose optimization in terms of effectiveness, simplicity and cost.

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Las imágenes en medicina nuclear y radiología son complementarias y su fusión permite una comprensión integrada, respondiendo a la necesidad de entregar al clínico un formato amigable y confiable de la información. Para SPECT (tomografía por emisión de fotón único) o PET (tomografía por emisión de positrones), distintos radiotrazadores (RT) administrados al paciente revelan el estado funcional de órganos y tumores. Por la relativa carencia de referentes anatómicos, SPECT y PET pueden requerir correlación morfológica dirigida. Su fusión con una tomografía computarizada (CT) o resonancia magnética (RM), constituye una pareja de imágenes de distinta modalidad; SPECT/CT, SPECT/RM, PET/ CT o PET/RM, capaz de localizar focos isotópicos en su estructura correspondiente, que puede o no estar alterada. Con el objetivo de evaluar el valor diagnostico de la Fusión de Imágenes en el Procesador de Imágenes IM512P propuesta por el autor como Protocolo a usarse en los servicios de Medicina Nuclear; se diseño un estudio Observacional, Transversal, Comparativo, Retrospectivo; en el Hospital de Policía Luis N Sáenz, durante los meses de enero a julio del 2007. Se realizo la recolección de imágenes e informes médicos, en las técnicas de Spect y Resonancia Magnética, de 38 pacientes para luego en la estación de trabajo del procesador de imágenes realizar la Fusión de las mismas, y así obtener resultados, y comparar con los valores ya establecidos de sensibilidad y especificidad. Los resultados mostraron valores de Sensibilidad de 96,55 por ciento con un índice de confiabilidad de 95 por ciento entre 88,19 por ciento y 100 por ciento, Especificidad de 77,78 por ciento con un índice de confiabilidad de 95 por ciento entre 45,06 por ciento y 100 por ciento, Valor Predictivo Positivo de 93,33 por ciento Valor Predictivo Negativo de 87,50 por ciento...

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Monitoring the quality of instrumentation used in nuclear medicine is mandatory to guarantee the clinical efficacy of medical practice. A national program for the quality control of nuclear medicine instruments was established in Cuba and was certified and approved by the regulatory authorities. The program, which establishes official regulations and audit services, sets up educational activities, distributes technical documentation, and maintains a national phantom bank, constitutes a valuable and useful tool to guarantee the quality of nuclear medicine instrumentation.

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At present, more than 75% of routine nuclear medicine diagnostic procedures use technetium-99m (99mTc). The binding between 99mTc and the drug to obtain the radiopharmaceutical needs a reducing agent, with stannous chloride (SnCl2) being one of the most used. There are controversies about the cytotoxic, genotoxic and mutagenic effects of SnCl2 in the literature. Thus, the approaches below were used to better understand the biological effects of this salt and its association in nuclear medicine kits [methylenediphosphonate (MDP) bone scintigraphy and diethylenetriaminepentaacetic acid (DTPA) kidney and brain scintigraphy]: (i) bacterial inactivation experiments; (ii) agarose gel electrophoresis of supercoiled and linear plasmid DNA and (iii) bacterial transformation assay. The Escherichia coli strains used here were AB1157 (wild type) and BW9091 (xthA mutant). Data obtained showed that both MDP and SnCl2 presented a high toxicity, but this was not observed when they were assayed together in the kit, thereby displaying a mutual protect effect. DTPA salt showed a moderate toxicity, and once more, the DTPA kit provided protection, compared to the SnCl2 effect alone. The results suggest a possible complex formation, either MDP-SnCl2 or DTPA-SnCl2, originating an atoxic compound. On the other hand, SnCl2-induced cell inactivation and the decrease in bacterial transformation generated by DTPA found in XthA mutant strain suggest that the lack of this enzyme could be responsible for the effects observed, being necessary to induce DNA damage repair.

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This paper describes the results obtained using a simulated test for administration of activity in nuclear medicine between 2002 and 2004. Measurements in the radionuclide calibrator are made during the different stages of the procedure. The test attempts to obtain supplementary information on the quality of the measurement, with the aim of evaluating in a more complete way the accuracy of the administered activity value compared with the prescribed one. The participants' performance has been assessed by means of a statistical analysis of the reported data. Dependences between several attributes of the simulated administration tests results are discussed. Specifically, the proportion of satisfactory results in the 2003-2004 period was found to be higher than in 2002. It reveals an improvement of the activity administration in the Cuban nuclear medicine departments since 2003.

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OBJETIVO: O objetivo deste trabalho foi estabelecer um padrão de trabalho para intercomparação e calibração de medidores de atividade (calibradores de dose) utilizados na maioria dos serviços de medicina nuclear, para determinação da atividade dos radionuclídeos administrados aos pacientes nos exames específicos ou nos procedimentos terapêuticos. MATERIAIS E MÉTODOS: Foi utilizado um calibrador de dose comercial, um conjunto de fontes radioativas padrões, além de seringas, frascos e ampolas contendo soluções de radionuclídeos utilizados em medicina nuclear. RESULTADOS: O calibrador de dose comercial foi calibrado com soluções de radionuclídeos utilizados em medicina nuclear. Os testes simples do instrumento, tais como o teste de linearidade e da variação da resposta com o volume da fonte a uma concentração de atividade constante, foram descritos e realizados. CONCLUSÃO: O instrumento estudado pode agora ser utilizado como sistema de referência para intercomparação e calibração de outros instrumentos medidores de atividade, como um método de controle da qualidade de calibradores de dose utilizados em serviços de medicina nuclear.

OBJECTIVE: The aim of this work was to establish a working standard for intercomparison and calibration of dose calibrators used in most of nuclear medicine facilities for the determination of the activity of radionuclides administered to patients in specific examinations or therapeutic procedures. MATERIALS AND METHODS: A commercial dose calibrator, a set of standard radioactive sources, and syringes, vials and ampoules with radionuclide solutions used in nuclear medicine were utilized in this work. RESULTS: The commercial dose calibrator was calibrated for radionuclide solutions used in nuclear medicine. Simple instrument tests, such as linearity response and variation response with the source volume at a constant source activity concentration were performed. CONCLUSION: This instrument may be used as a reference system for intercomparison and calibration of other activity meters, as a method of quality control of dose calibrators utilized in nuclear medicine facilities

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INTRODUCTION: Thanks to the technological evolution of the different imaging techniques, which are now increasingly precise, the surgical or, more specifically, neurosurgical treatment of certain brain lesions has made tremendous strides. The main challenge in stereotactic radiosurgery (SRS) was to offer greater efficacy while at the same time minimizing the risk. The emergence of approaches using various types of rays (electron, gamma, etc.) and the constant evolution of nuclear physics fostered the development of a new approach in neurosurgery stereotactic radioneurosurgery. This type of treatment consists in exposing a lesion of small volume, determined by three -dimensional imaging, to a single high dose of ionizing rays while at the same time minimizing the dose absorbed by the surrounding structures. What is unique about SRS is that it allows one to treat lesions (e.g., the destruction of tumors) without making a surgical incision. With SRS, very delicate and hard -to-reach areas can be treated (e.g., near the optic chiasma) where surgery is not possible because of the risks inherent in the surgical procedures (e.g., hemorrhage, irreversible lesions). The fact that the procedure involves less traumatic intervention conditions (local anesthesia) is the other attractive feature of this technique. The cyclotron, linear accelerator and gamma knife are the three main types of instruments used in SRS. They differ from each other by their radiation source and their mobility in relation to the patient. METHODOLOGY: A literature search was performed in the Medline, Cochrane Library, Embase and HealthStar databases, and was supplemented with reports from a number of health technology assessment agencies that had looked at SRS. Upon examining the relevant scientific data, it was observed that: -There has been a very large number of study reports on the efficacy of SRS, especially in the past ten years; -Almost all of the studies have been of the retrospective type, with no randomization or comparison; -Very few or even no comparative studies have examined the use of the gamma knife and linear accelerator (adapted or dedicated) for specific indications. Very few economic studies comparing the various instruments have been carried out, and for the most part, they are considered in the reports published by national assessment agencies. CONCLUSIONS: The efficacy of SRS has been established for a certain number of indications, including brain metastases, arteriovenous malformations, as an alternative to conventional surgery in cases of interventional difficulties, and in the prevention of the complications of the standard treatments in cases of meningioma and vestibular schwannoma. SRS is a promising approach in the treatment of pituitary adenomas, certain skull base tumors, and specific functional disorders. Given the evolution of the technologies and the costs associated with SRS, the instruments that might best meet the efficacy and safety criteria are the dedicated linear accelerator and the gamma knife. The use of an adapted linear accelerator is possible but limited in cases of lesions in very close proximity to sensitive structures, since the manipulations required to adapt the equipment in order to perform SRS can be a source of imprecision when focussing the beams. Furthermore, the need to perform quality control before each treatment lengthens the treatment time. Presently, SRS facilities are clearly needed in Québec. If we consider all the lesions eligible for SRS on the basis of the existing data and evaluations, more than 300 patients could benefit from SRS. Even if, in theory, the gamma knife and dedicated linear accelerator are both more suitable for the various indications for SRS, technological developments in the specific area of SRS (especially in the case of the dedicated linear accelerator) and the lack of randomized, controlled trials concerning a given indication do not permit us to conclude that either of these instruments is superior to the other from the standpoint of efficacy. However, the degree of precision offered by the gamma knife permits the treatment of lesions that are no more than 2 mm in size and which touch vital structures, such as the cranial nerves, optic chiasma and brainstem, without (theoretically) causing any injury to healthy tissues. Given the current knowledge about the clinical, economic, technical and epidemiological aspects and given the need to adequately fulfill the offer of SRS services and to adequately meet research needs, the Agency recommends that a specialized radiosurgery centre with a gamma knife be created at a university hospital. Where this specialized centre will be set up will depend on geographical and/or functional accessibility and well-established service pathways. The institution chosen must have the necessary logistical wherewithal (structural and professional) needed to perform this type of treatment. The mandatory presence of a multidisciplinary team (neurosurgeon, neuroradiologist, radiation therapist, radiophysicist, paramedical personnel), the need to provide continuous patient management quality and the need to promote the acquisition of new professional skills clearly warrant creating the centre at a university hospital.

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Nuclear Endocrinology was the first clinical use of radionuclides, five decades ago. From those days to the present, nuclear medicine has a definitive role in the diagnosis of a great variety of clinical situations, from the very frequent thyroid nodule to the unusual neuroendocrine tumors, including parathyroid hyperfunctioning tissue. Radioiodine I131 still remains a very effective treatment for differentiated thyroid cancer and whole body scan with I131 in conjunction with seric Tyroglobulin level are the main follow-up strategies for these tumors. New techniques, like positron emission tomography (PET) and newer radiolabeled peptides, among others, will offer a molecular approach to the 21st century clinical nuclear medicine.

Se presentan las principales indicaciones actuales de los estudios radioisotópicos en endocrinología clínica, y su situación relativa con el resto de las técnicas de imagen no invasivas disponibles en nuestro medio. Se discuten brevemente las nuevas aplicaciones terapéuticas y su potencial desarrollo.

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Bone scan, planar or Spect (single photon emission computed tomography) technique is the most frequently nuclear medicine procedures used in the osteoarticular applications. Other procedure, especially Galium 67, is also used. Bone scan is a safe, painless and cost-effective procedure to get information in a wide variety of diseases: malignancies, sports injuries, fractures, infections, inflammations, etc. Very early in the course of these diseases, it is possible to obtain a positive bone scan that reflects both: osteoblastic activity and skeletal vascular abnormalities. However the specificity is much less than the sensitivity of the bone scan procedure, but frequently the final diagnosis can be made by correlating the bone image with clinical data and radiographic findings.

La mayor parte del área osteoarticular en medicina nuclear, tiene como principal examen la cintigrafía ósea, ya sea planar o con técnica SPECT (single photon emision computed tomography). Existen algunos otros exámenes usados como el estudio con Galio-67, en el área de prótesis e infecciones. La sensibilidad, facilidad y seguridad en su realización, lo han hecho un examen altamente solicitado. Una amplia variedad de patologías (tumorales, inflamatorias, infecciosas, traumáticas, etc) producen alteraciones cintigráficas, ya sea por alteración osteoblástica o alteraciones de flujo, y aunque esto hace disminuir su especificidad, existen algunos patrones que claramente orientan a una patología u otra. Por otro lado, la interpretación del examen en el contexto clínico y en conjunto con los exámenes anatómicos del paciente, permite un excelente rendimiento diagnóstico.

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En los últimos diez años, a excepción de la cardiología nuclear, los adelantos en medicina nuclear han sido más lentos que los rápidos avances observados en otras modalidades de imagenología como el ultrasonido, la resonancia magnética y la tomografía computarizada. Estas técnicas de visualización han ampliado rápidamente su papel en la evaluación del paciente, en muchos casos a costa de procedimientos de medicina nuclear. Es difícil que las técnicas de imagenología nuclear compitan con otras modalidades de base anatómico debido a que la demostración de anormalidades anatómicas no es una de las mayores cualidades de la medicina nuclear dado que estos estudios producen un detalle visual inherentemente bajo. Sólo cuando las diferencias funcionales entre estructuras anormales pueden ser explotadas es que la medicina nuclear ofrece claras ventajas sobre otras técnicas de imágenes que sólo muestran detalles anatómicos. Los adelantos recientes en el instrumental nuclear y los nuevos productos radiofarmacéuticos están abriendo nuevas aplicaciones en la medicina nuclear que no existían o eran económicamente imprácticas hace algunos años. Este artículo trata de explicar brevemente algunas innovaciones en técnicas y equipos y sus posibles usos.

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O objetivo deste estudo foi comparar valores de captaçäo tireoidiana medidos em dois equipamentos diferentes: uma sonda própria para as medidas de captaçäo (Captus 600© - Capintec, USA) e uma mini gama-câmera (Thyrus© - Adac Laboratories). Foram estudados 122 pacientes, sendo 110 do sexo feminino e 12 do sexo masculino, com idades variando de 4 a 81 anos (média de 42,2 anos). Administraram-se, por via oral, doses de 0,74 MBq a 3,7 MBq de NaûüûI e as medidas de captaçäo tireoidiana foram realizadas cerca de 24 horas após, em ambos os equipamentos. Para o cálculo da captaçäo utilizou-se, nos dois casos, a medida de um tubo contendo soluçäo padräo devidamente colocado em um "phantom" de pescoço. Aplicou-se o teste de Wilcoxon aos valores obtidos, resultando em z calculado de -4,35, com nível de significância p < 0,001, levando-nos à conclusäo de que há significativa diferença nas medidas de captaçäo nos dois equipamentos

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Recording the chronology of nuclear medicine instrumentation poses some difficult decisions as does the determination of the "father" of nuclear medicine?. Historians can agree on well-defined dates and events, but many of them are subjective and reside in the memories of those of us who were fortunate to experience the formative years of our field. We all search for the historical truth. The highlights of this story may begin with John Lawrence and phosphorus-32 therapy at Berkeley and continue with Enrico Fermi's sustained nuclear reaction, which lead to the Manhattan Project, then the Atomic Energy Commission, and finally, Sam Seidlin's treatment of thyroid metastases with iodine-131. The rectilinear scanner came to us from Benedict Cassen and was followed by Hal O. Anger and his gamma scintillation camera, one of the most pivotal developments in the field. A plethora of cameras followed: Merrill Benders's digital autofluroscope, Dave Kuhl's efforts for tomographic imaging, and then on to single photon emission computed tomography. Finally, we come back to Hal O. Anger, who suggested and worked with the idea of a positron camera, with positron emission tomography becoming commercially available in 1985. Ours is a variegated history, and I hope that this account speaks the historical truth.

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