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1.
Diagnostics (Basel) ; 14(4)2024 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-38396480

RESUMEN

BACKGROUND: This study is a systematic review with meta-analysis comparing radioactive seed localization (RSL) versus radio-guided occult lesion localization (ROLL) and wire-guided localization (WGL) for patients with impalpable breast cancer undergoing breast-conserving surgery and evaluating efficacy, safety, and logistical outcomes. The protocol is registered in PROSPERO with the number CRD42022299726. METHODS: A search was conducted in the Embase, Lilacs, Pubmed, Scielo, Web of Science, and clinicaltrials.gov databases, in addition to a manual search in the reference list of relevant articles, for randomized clinical trials and cohort studies. Studies selected were submitted to their own data extraction forms and risk of bias analysis according to the ROB 2 and ROBINS 1 tools. A meta-analysis was performed, considering the random effect model, calculating the relative risk or the mean difference for dichotomous or continuous data, respectively. The quality of the evidence generated was analyzed by outcome according to the GRADE tool. Overall, 46 articles met the inclusion criteria and were included in this systematic review; of these, 4 studies compared RSL and ROLL with a population of 1550 women, and 43 compared RSL and WGL with a population of 19,820 women. RESULTS: The results showed that RSL is a superior method to WGL in terms of surgical efficiency in the impalpable breast lesions' intraoperative localization, and it is at least equivalent to ROLL. Regarding security, RSL obtained results equivalent to the already established technique, the WGL. In addition to presenting promising results, RSL has been proven to be superior to WGL and ROLL technologies.

2.
Preprint en Portugués | SciELO Preprints | ID: pps-5834

RESUMEN

Nuclear Medicine is crucial for the care of patients with diseases, especially oncological and cardiovascular ones. However, access to it is unequal due to the lack of equipment and producing and supplying units of inputs. Current legislation does not adequately address these aspects, and the dominance of foreign capital is a concern, as it can lead to the scrapping of the current system. National production of radiopharmaceuticals has suffered numerous setbacks, such as budget cuts, indiscriminate market opening, and delays in completing the Brazilian Multipurpose Reactor project. Public data from 2015 to 2021 were analyzed to evaluate access to Nuclear Medicine by the Brazilian Unified Health System (SUS), including the number of facilities, procedures, tariffs, and trade balance. Although Brazil has many Nuclear Medicine facilities, its geographic distribution is extremely uneven. Factors such as equipment acquisition and maintenance costs and lack of qualified personnel are real obstacles to the expansion of Nuclear Medicine in Brazil. The country is financially dependent on foreign capital for this area, which limits its expansion according to SUS guidelines. Social and economic policies are necessary to minimize SUS technological vulnerabilities, promote system sustainability, and ensure universal and equitable access to specialized healthcare services.


A Medicina Nuclear é crucial para o cuidado de pacientes com doenças, especialmente oncológicas e cardiovasculares. No entanto, o acesso a ela é desigual, devido à falta de equipamentos e unidades produtoras e fornecedoras de insumos. As legislações atuais não abordam adequadamente esses aspectos, e o domínio do capital externo é uma preocupação, pois pode levar ao sucateamento do parque atual. A produção nacional de radiofármacos tem sofrido inúmeros reveses, como cortes orçamentários, a abertura indiscriminada de mercado e o atraso na conclusão do projeto do Reator Multipropósito Brasileiro. Foram analisados dados públicos de 2015 a 2021 para avaliar o acesso à Medicina Nuclear pelo SUS, incluindo o número de instalações, procedimentos, tarifas e balança comercial. Embora o Brasil tenha muitas instalações de Medicina Nuclear, sua distribuição geográfica é extremamente desigual. Fatores como custos de aquisição e manutenção de equipamentos e falta de pessoal qualificado são obstáculos reais à expansão da MN no Brasil. O país é financeiramente dependente de capital estrangeiro para essa área, o que limita a expansão da área de acordo com as diretrizes do SUS. Políticas sociais e econômicas são necessárias para minimizar as vulnerabilidades tecnológicas do SUS, promover a sustentabilidade do sistema e garantir o acesso universal e equânime aos serviços especializados de saúde.

3.
Photochem Photobiol ; 99(2): 519-528, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36004458

RESUMEN

Several diseases or conditions cause dermatological disorders that hinder the process of skin repair. The search for novel technologies has inspired the combination of stem cell (SC) and light-based therapies to ameliorate skin wound repair. Herein, we systematically revised the impact of photobiomodulation therapy (PBM) combined with SCs in animal models of skin wounds and quantitatively evaluated this effect through a meta-analysis. For inclusion, SCs should be irradiated in vitro or in vivo, before or after being implanted in animals, respectively. The search resulted in nine eligible articles, which were assessed for risk of bias. For the meta-analysis, studies were included only when PBM was applied in vivo, five regarding wound closure, and three to wound strength. Overall, a positive influence of SC + PBM on wound closure (mean difference: 9.69; 95% CI: 5.78-13.61, P < 0.00001) and strength (standardized mean difference: 1.7, 95% CI: 0.68-2.72, P = 0.001) was detected, although studies have shown moderate to high heterogeneity and a lack of information regarding some bias domains. Altogether, PBM seems to be an enabling technology able to be applied postimplantation of SCs for cutaneous regeneration. Our findings may guide future laboratory and clinical studies in hopes of offering wound care patients a better quality of life.


Asunto(s)
Terapia por Luz de Baja Intensidad , Cicatrización de Heridas , Animales , Calidad de Vida , Piel , Tratamiento Basado en Trasplante de Células y Tejidos
4.
São Paulo; Scielo Prepints; 2023.
No convencional en Portugués | CONASS, Sec. Est. Saúde SP, SESSP-ISPROD, Sec. Est. Saúde SP | ID: biblio-1428491

RESUMEN

A Medicina Nuclear é crucial para o cuidado de pacientes com doenças, especialmente oncológicas e cardiovasculares. No entanto, o acesso a elaé desigual, devido à falta de equipamentos e unidades produtoras e fornecedoras de insumos. As legislações atuais não abordam adequadamente esses aspectos, e o domínio do capital externo é uma preocupação, pois pode levar ao sucateamento do parque atual. A produção nacional de radiofármacos tem sofrido inúmeros reveses, como cortes orçamentários, a abertura indiscriminada de mercado e o atraso na conclusão doprojeto do Reator Multipropósito Brasileiro. Foram analisados dados públicos de 2015 a 2021 para avaliar o acesso à Medicina Nuclear pelo SUS, incluindo o número de instalações, procedimentos, tarifas e balança comercial.Embora o Brasil tenha muitas instalações de Medicina Nuclear, sua distribuição geográfica é extremamente desigual. Fatores como custosde aquisiçãoemanutençãode equipamentose falta de pessoal qualificado são obstáculos reais à expansão da MN no Brasil. Opaís é financeiramente dependente de capital estrangeiro para essa área, o que limita a expansão da áreade acordo com as diretrizes do SUS. Políticas sociais e econômicas são necessárias para minimizar as vulnerabilidades tecnológicas do SUS, promover a sustentabilidade do sistema e garantir o acesso universal e equânimeaos serviços especializados de saúde.


Asunto(s)
Diagnóstico por Imagen , Radiofármacos , Medicina Nuclear , Cintigrafía , Tomografía Computarizada por Tomografía de Emisión de Positrones
5.
Rev. Bras. Cancerol. (Online) ; 69(2)abr.-jun. 2023.
Artículo en Inglés | LILACS, Sec. Est. Saúde SP | ID: biblio-1452275

RESUMEN

Introduction: Prostate cancer is the second most common cancer in men worldwide. In Brazil, regional disparities in incidences of intermediate and high-risk in late-diagnosed PC cases are expected. Objective: To investigate the clinical and demographic profiles of patients treated with metastatic castration-resistant prostate cancer (mCRPC) in Brazil, using real-world data from public databases. Method: Prostate cancer data from the Brazilian cancer registries were filtered from Brazilian public databases from 2008 to 2018. The number of health institutions and registries at a cancer public database were used to separate the Brazilian Federative Units into two comparison groups. mCRPC patients were estimated by using a combination of filters of staging and treatment (Tx, Nx and M1 + chemotherapy). The patients' median age and the number and type of treatments were evaluated. Results: A total of 325,987 patients with prostate cancer and 5,367 patients with mCRPC were identified. The median age of the mCRPC patients was 63 years. The percentage of patients who underwent one, two or three treatments was 21.0%, 43.2% and 28.1%, respectively. In addition, management differences were noticed depending on the group analyzed. Conclusion: The results revealed regional discrepancies in the distribution of registered mCRPC patients in the Brazilian territory and in their treatment. This information can be used to strengthen the recently updated treatment and improve the palliative care offered. This work presents suggestions to improve specific prostate cancer databases


Introdução: O câncer de próstata é o segundo tipo mais comum em homens ao redor do mundo. No Brasil, diferenças regionais de incidência em casos de risco intermediário e alto tardiamente diagnosticados são esperadas. Objetivo: Investigar os perfis clínico e demográfico de pacientes com câncer de próstata metastático resistente à castração (mCRPC) tratados no Brasil usando dados do mundo real de bancos de dados públicos brasileiros. Método: Os casos de câncer de próstata foram filtrados a partir dos registros brasileiros de câncer no período de 2008 a 2018. O número de instituições de saúde que registram esses casos foi usado para separar as Unidades Federativas brasileiras em dois grupos. O número de pacientes com mCRPC foi estimado usando uma combinação de filtros de estadiamento e tratamento (Tx, Nx e M1 + quimioterapia). A idade média e o número e tipos de tratamento realizados foram avaliados. Resultados: O estudo identificou 325.987 pacientes com câncer de próstata e 5.367 com mCRPC. A mediana das idades de pacientes com mCRPC foi de 63 anos. O percentual de pacientes submetidos a um, dois ou três tratamentos foi de 21,0%, 43,2% e 28,1%, respectivamente. Foram observadas diferenças de manejo nos grupos analisados. Conclusão: Os resultados revelaram diferenças regionais nas distribuições de pacientes com mCRPC no território brasileiro e no manejo da doença. Essa informação pode subsidiar decisões de incorporação de novos tratamentos e de melhoria dos cuidados paliativos oferecidos aos pacientes com mCRPC. Este trabalho apresenta sugestões para o desenvolvimento de bancos de dados específicos para câncer de próstata e aprimoramento dos já existentes


Introducción: El cáncer de próstata es el segundo tipo más común en hombres en el mundo. En el Brasil, se espera encontrar diferencias regionales en la incidencia de diagnósticos tardíos de riesgo intermedio y alto. Objetivo: Investigar los perfiles clínico y demográfico de pacientes con cáncer de próstata metastásico resistente a la castración (mCRPC) tratados en el Brasil utilizando datos del mundo real de bases de datos públicas brasileñas. Método: Los casos de cáncer de próstata fueron filtrados a partir de los registros brasileños de cáncer nel período de 2008 a 2018. El número de instituciones registradoras en la base de datos fue utilizado para separar los Estados Brasileños en dos grupos para comparación. El número de pacientes se estimó mediante una combinación de filtros de estadio y tratamiento (Tx, Nx y M1 + quimioterapia). Fueron evaluados la edad media y la cantidad y tipos de tratamiento realizados. Resultados: Se identificaron un total de 325.987 pacientes con cáncer de próstata y 5367 pacientes con mCRPC. La mediana de la edad de los pacientes con mCRPC fue de 63 años. El porcentaje de pacientes sometidos a uno, dos o tres tratamientos fue del 21,0%, 43,2% y 28,1%. Fueron observadas diferencias de manejo según el grupo analizado. Conclusión: Fueron reveladas diferencias regionales en la distribución de los pacientes con mCRPC en el Brasil y, especialmente, en el manejo de la enfermedad a partir de bases de datos públicas. Esta información puede apoyar las decisiones de incorporar nuevos tratamientos y mejorar los cuidados ofrecidos a los pacientes. Se presentan sugerencias para el desarrollo de bases de datos específicas y la mejora de las existentes


Asunto(s)
Humanos , Masculino , Femenino , Neoplasias de la Próstata Resistentes a la Castración , Reportes Públicos de Datos en Atención de Salud , Metástasis de la Neoplasia
6.
Front Neurosci ; 14: 5, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32063826

RESUMEN

Exposure to environmental tobacco smoke (ETS) is associated with high morbidity and mortality, mainly in childhood. Our aim was to evaluate the effects of postnatal ETS exposure in the brain 2-deoxy-2-[18F]-fluoro-D-glucose (18F-FDG) uptake of mice by positron emission tomography (PET) neuroimaging in a longitudinal study. C57BL/6J mice were exposed to ETS that was generated from 3R4F cigarettes from postnatal day 3 (P3) to P14. PET analyses were performed in male and female mice during infancy (P15), adolescence (P35), and adulthood (P65). We observed that ETS exposure decreased 18F-FDG uptake in the whole brain, both left and right hemispheres, and frontal cortex in both male and female infant mice, while female infant mice exposed to ETS showed decreased 18F-FDG uptake in the cerebellum. In addition, all mice showed reduced 18F-FDG uptake in infancy, compared to adulthood in all analyzed VOIs. In adulthood, ETS exposure during the early postnatal period decreased brain 18F-FDG uptake in adult male mice in the cortex, striatum, hippocampus, cingulate cortex, and thalamus when compared to control group. ETS induced an increase in 18F-FDG uptake in adult female mice when compared to control group in the brainstem and cingulate cortex. Moreover, male ETS-exposed animals showed decreased 18F-FDG uptake when compared to female ETS-exposed in the whole brain, brainstem, cortex, left amygdala, striatum, hippocampus, cingulate cortex, basal forebrain and septum, thalamus, hypothalamus, and midbrain. The present study shows that several brain regions are vulnerable to ETS exposure during the early postnatal period and these effects on 18F-FDG uptake are observed even a long time after the last exposure. This study corroborates our previous findings, strengthening the idea that exposure to tobacco smoke in a critical period interferes with brain development of mice from late infancy to early adulthood.

7.
Artif Cells Nanomed Biotechnol ; 46(sup1): 1080-1087, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29482360

RESUMEN

Cancer is responsible for more than 12% of all causes of death in the world, with an annual death rate of more than 7 million people. In this scenario melanoma is one of the most aggressive ones with serious limitation in early detection and therapy. In this direction we developed, characterized and tested in vivo a new drug delivery system based on magnetic core-mesoporous silica nanoparticle that has been doped with dacarbazine and labelled with technetium 99 m to be used as nano-imaging agent (nanoradiopharmaceutical) for early and differential diagnosis and melanoma by single photon emission computed tomography. The results demonstrated the ability of the magnetic core-mesoporous silica to be efficiently (>98%) doped with dacarbazine and also efficiently labelled with 99mTc (technetium 99 m) (>99%). The in vivo test, using inducted mice with melanoma, demonstrated the EPR effect of the magnetic core-mesoporous silica nanoparticles doped with dacarbazine and labelled with technetium 99 metastable when injected intratumorally and the possibility to be used as systemic injection too. In both cases, magnetic core-mesoporous silica nanoparticles doped with dacarbazine and labelled with technetium 99 metastable showed to be a reliable and efficient nano-imaging agent for melanoma.


Asunto(s)
Dacarbazina/química , Imanes/química , Melanoma/diagnóstico por imagen , Nanopartículas/química , Dióxido de Silicio/química , Tecnecio/química , Tomografía Computarizada de Emisión de Fotón Único/métodos , Animales , Línea Celular Tumoral , Transformación Celular Neoplásica , Diagnóstico Diferencial , Detección Precoz del Cáncer , Humanos , Marcaje Isotópico , Melanoma/patología , Ratones , Ratones Endogámicos BALB C , Metástasis de la Neoplasia , Porosidad
8.
Z Med Phys ; 27(2): 98-112, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27105765

RESUMEN

Accurate quantitation of activity provides the basis for internal dosimetry of targeted radionuclide therapies. This study investigated quantitative imaging capabilities at sites with a variety of experience and equipment and assessed levels of errors in activity quantitation in Single-Photon Emission Computed Tomography (SPECT) and planar imaging. Participants from 9 countries took part in a comparison in which planar, SPECT and SPECT with X ray computed tomography (SPECT-CT) imaging were used to quantify activities of four epoxy-filled cylinders containing 133Ba, which was chosen as a surrogate for 131I. The sources, with nominal volumes of 2, 4, 6 and 23mL, were calibrated for 133Ba activity by the National Institute of Standards and Technology, but the activity was initially unknown to the participants. Imaging was performed in a cylindrical phantom filled with water. Two trials were carried out in which the participants first estimated the activities using their local standard protocols, and then repeated the measurements using a standardized acquisition and analysis protocol. Finally, processing of the imaging data from the second trial was repeated by a single centre using a fixed protocol. In the first trial, the activities were underestimated by about 15% with planar imaging. SPECT with Chang's first order attenuation correction (Chang-AC) and SPECT-CT overestimated the activity by about 10%. The second trial showed moderate improvements in accuracy and variability. Planar imaging was subject to methodological errors, e.g., in the use of a transmission scan for attenuation correction. The use of Chang-AC was subject to variability from the definition of phantom contours. The project demonstrated the need for training and standardized protocols to achieve good levels of quantitative accuracy and precision in a multicentre setting. Absolute quantification of simple objects with no background was possible with the strictest protocol to about 6% with planar imaging and SPECT (with Chang-AC) and within 2% for SPECT-CT.


Asunto(s)
Fantasmas de Imagen/normas , Tomografía Computarizada de Emisión de Fotón Único/normas , Humanos , Procesamiento de Imagen Asistido por Computador , Radiometría , Reproducibilidad de los Resultados , Tomografía Computarizada de Emisión de Fotón Único/métodos
9.
Radiol. bras ; 47(3): 141-148, May-Jun/2014. tab, graf
Artículo en Portugués | LILACS | ID: lil-713636

RESUMEN

Objetivo: Investigar o acesso a procedimentos ambulatoriais de medicina nuclear por intermédio do Sistema Único de Saúde (SUS) do Brasil e analisar a correspondência dos dados fornecidos por este sistema com os da Comissão Nacional de Energia Nuclear (CNEN). Materiais e Métodos: Foram obtidos e avaliados os dados disponíveis no Datasus quanto a quantidade de câmaras de cintilação, procedimentos ambulatoriais de 2008 a 2012, esfera administrativa responsável por estes procedimentos, tipo de prestador de serviços e terceirização de serviços. Também foi feita comparação com os dados de estabelecimentos autorizados pela CNEN. Resultados: O estudo mostrou que ainda falta amadurecimento do sistema quanto à sua completa alimentação, especialmente no campo de equipamentos disponíveis. Foi possível elencar os procedimentos mais realizados e verificar o crescimento da especialidade no período estudado. Estabelecimentos privados são responsáveis pela maior parte dos procedimentos cobertos pelo SUS. Entretanto, muitos estabelecimentos de saúde não são autorizados pela CNEN. Conclusão: O Datasus oferece dados importantes para uma análise como a feita neste estudo, embora alguns pontos ainda demandem atenção. O trabalho mostrou, quantitativamente, a realidade brasileira quanto ao acesso a procedimentos de medicina nuclear oferecidos pelo/para o SUS. .


Objective: To investigate the outpatient access to nuclear medicine procedures by means of the Brazilian Unified Health System (SUS), analyzing the correspondence between data provided by this system and those from Comissão Nacional de Energia Nuclear (CNEN) (National Commission of Nuclear Energy). Materials and Methods: Data provided by Datasus regarding number of scintillation chambers, outpatient procedures performed from 2008 to 2012, administrative responsibility for such procedures, type of service providers and outsourced services were retrieved and evaluated. Also, such data were compared with those from institutions certified by CNEN. Results: The present study demonstrated that the system still lacks maturity in terms of correct data input, particularly regarding equipment available. It was possible to list the most common procedures and check the growth of the specialty along the study period. Private centers are responsible for most of the procedures covered and reimbursed by SUS. However, many healthcare facilities are not certified by CNEN. Conclusion: Datasus provides relevant data for analysis as done in the present study, although some issues still require attention. The present study has quantitatively depicted the Brazilian reality regarding access to nuclear medicine procedures offered by/for SUS. .

10.
Radiol Bras ; 47(3): 141-8, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25741070

RESUMEN

OBJECTIVE: To investigate the outpatient access to nuclear medicine procedures by means of the Brazilian Unified Health System (SUS), analyzing the correspondence between data provided by this system and those from Comissão Nacional de Energia Nuclear (CNEN) (National Commission of Nuclear Energy). MATERIALS AND METHODS: Data provided by Datasus regarding number of scintillation chambers, outpatient procedures performed from 2008 to 2012, administrative responsibility for such procedures, type of service providers and outsourced services were retrieved and evaluated. Also, such data were compared with those from institutions certified by CNEN. RESULTS: The present study demonstrated that the system still lacks maturity in terms of correct data input, particularly regarding equipment available. It was possible to list the most common procedures and check the growth of the specialty along the study period. Private centers are responsible for most of the procedures covered and reimbursed by SUS. However, many healthcare facilities are not certified by CNEN. CONCLUSION: Datasus provides relevant data for analysis as done in the present study, although some issues still require attention. The present study has quantitatively depicted the Brazilian reality regarding access to nuclear medicine procedures offered by/for SUS.


OBJETIVO: Investigar o acesso a procedimentos ambulatoriais de medicina nuclear por intermédio do Sistema Único de Saúde (SUS) do Brasil e analisar a correspondência dos dados fornecidos por este sistema com os da Comissão Nacional de Energia Nuclear (CNEN). MATERIAIS E MÉTODOS: Foram obtidos e avaliados os dados disponíveis no Datasus quanto a quantidade de câmaras de cintilação, procedimentos ambulatoriais de 2008 a 2012, esfera administrativa responsável por estes procedimentos, tipo de prestador de serviços e terceirização de serviços. Também foi feita comparação com os dados de estabelecimentos autorizados pela CNEN. RESULTADOS: O estudo mostrou que ainda falta amadurecimento do sistema quanto à sua completa alimentação, especialmente no campo de equipamentos disponíveis. Foi possível elencar os procedimentos mais realizados e verificar o crescimento da especialidade no período estudado. Estabelecimentos privados são responsáveis pela maior parte dos procedimentos cobertos pelo SUS. Entretanto, muitos estabelecimentos de saúde não são autorizados pela CNEN. CONCLUSÃO: O Datasus oferece dados importantes para uma análise como a feita neste estudo, embora alguns pontos ainda demandem atenção. O trabalho mostrou, quantitativamente, a realidade brasileira quanto ao acesso a procedimentos de medicina nuclear oferecidos pelo/para o SUS.

11.
Rev. imagem ; 31(3/4): 45-50, jul.-dez. 2009. ilus, graf
Artículo en Portugués | LILACS | ID: lil-613742

RESUMEN

OBJETIVO: Avaliação da correção do efeito de volume parcial pelo método iterativo de Van Cittertem medicina nuclear, usando um phantom matemático. MATERIAL E MÉTODO: Foi simulada uma imagem de quatro fontes circulares de diferentes diâmetros com intensidade igual a 255 por pixel.O algoritmo iterativo de Van Cittert foi aplicado com 20 iterações e α = 1. Foram obtidas as contagensmáximas e médias na imagem inteira e em regiões de interesse colocadas sobre cada uma das fontes. Também foram extraídos os perfis de contagem traçados ao longo do diâmetro de cada uma das fontes. RESULTADOS: A convergência local depende do tamanho da fonte estudada: quanto menor a fonte, maior o número de iterações necessário. Também depende da informação extraída: a contagem média fornece informações mais homogêneas que a contagem máxima. Há melhora significativa do contraste da imagem. CONCLUSÃO: Este estudo mostrou a possibilidade de melhora quantitativa e qualitativa ao aplicar o método bidimensional de Van Cittert em imagens de geometria simples.


OBJECTIVE: Assessment of Van Cittert partial volume effect correctionmethod in nuclear medicine images, with a mathematical phantom. MATERIAL AND METHOD: We simulated an image of four circular sources of different diameters and intensity of 255 per pixel. The iterative algorithm was applied with 20 iterations and α = 1. We obtained the maximum and average counts on the entire image and in regions of interest placed on each of the sources. We also extracted count profiles plotted along the diameter of each of the sources. RESULTS: The local convergence depends on the size of the source studied: the smaller the source, the greater the number of iterations required. It also depends on the information extracted: the use of average counts provides more homogeneous results than the maximum count. There is a significant improvement in imagecontrast. CONCLUSION: This study showed the possibility of qualitativeand quantitative improvement in applying the bidimensionaliterative Van Cittert method to images of simple geometry.


Asunto(s)
Medicina Nuclear , Fantasmas de Imagen , Estudios de Evaluación como Asunto , Tomografía de Emisión de Positrones/instrumentación
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