11 research outputs found

    Patient-specific Monte Carlo-based organ dose estimates in spiral CT via optical 3D body scanning and adaptation of a voxelized phantom dataset: proof-of-principle

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    : Objective. We present a method for personalized organ dose estimates obtained before the CT exam, via 3D optical body scanning and Monte Carlo (MC) simulations.Approach. A voxelized phantom is derived by adapting a reference phantom to the body size and shape measured with a portable 3D optical scanner, which returns the 3D silhouette of the patient. This was used as an external rigid envelope for incorporating a tailored version of the internal body anatomy derived from a phantom dataset (National Cancer Institute, NIH, USA) matched for gender, age, weight, and height. The proof-of-principle was conducted on adult head phantoms. The Geant4 MC code provided estimates of the organ doses from 3D absorbed dose maps in voxelized body phantom.Main results. We applied this approach for head CT scanning using an anthropomorphic voxelized head phantom derived from 3D optical scans of mannequins. We compared the estimates of head organ doses with those provided by the NCICT3.0 software (NCI, NIH, USA). Head organ doses differed up to 38% using the proposed personalized estimate and MC code, with respect to corresponding estimates calculated for the standard (non-personalized) reference head phantom. Preliminary application of the MC code to chest CT scans is shown. Real-time pre-exam personalized CT dosimetry is envisaged with adoption of a GPU-based fast MC code.Significance. The developed procedure for personalized organ dose estimates before the CT exam, introduces a new approach for realistic description of size and shape of patients via voxelized phantoms specific for each patient

    What is the role of the placebo effect for pain relief in neurorehabilitation? Clinical implications from the Italian consensus conference on pain in neurorehabilitation

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    Background: It is increasingly acknowledged that the outcomes of medical treatments are influenced by the context of the clinical encounter through the mechanisms of the placebo effect. The phenomenon of placebo analgesia might be exploited to maximize the efficacy of neurorehabilitation treatments. Since its intensity varies across neurological disorders, the Italian Consensus Conference on Pain in Neurorehabilitation (ICCP) summarized the studies on this field to provide guidance on its use. Methods: A review of the existing reviews and meta-analyses was performed to assess the magnitude of the placebo effect in disorders that may undergo neurorehabilitation treatment. The search was performed on Pubmed using placebo, pain, and the names of neurological disorders as keywords. Methodological quality was assessed using a pre-existing checklist. Data about the magnitude of the placebo effect were extracted from the included reviews and were commented in a narrative form. Results: 11 articles were included in this review. Placebo treatments showed weak effects in central neuropathic pain (pain reduction from 0.44 to 0.66 on a 0-10 scale) and moderate effects in postherpetic neuralgia (1.16), in diabetic peripheral neuropathy (1.45), and in pain associated to HIV (1.82). Moderate effects were also found on pain due to fibromyalgia and migraine; only weak short-term effects were found in complex regional pain syndrome. Confounding variables might have influenced these results. Clinical implications: These estimates should be interpreted with caution, but underscore that the placebo effect can be exploited in neurorehabilitation programs. It is not necessary to conceal its use from the patient. Knowledge of placebo mechanisms can be used to shape the doctor-patient relationship, to reduce the use of analgesic drugs and to train the patient to become an active agent of the therapy

    Avaliação das alterações nos atributos físicos e químicos de um latossolo vermelho-amarelo submetido à aplicação de água de reúso

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    Orientador: Prof. Dr. Claudinei Fonseca SouzaDissertação (Mestrado) - Universidade de Taubaté, Programa de Pós-graduação em Ciências Ambientais do Departamento Ciências Agrárias, Taubaté, 2008.Made available in DSpace on 2019-08-15T23:13:43Z (GMT). No. of bitstreams: 1 Antonio Claudio Testa Varallo.pdf: 966757 bytes, checksum: 16bf67208eff49c6fdb8822433544cfc (MD5) Previous issue date: 2008Resumo: A utilização do efluente de esgoto tratado para poupar os corpos d'água utilizados para irrigação tem sido de grande interesse na agricultura, e o uso não regulamentado desta prática pode acarretar mudanças no comportamento físico-químico e microbiológico do solo. Sua prática tem sido de grande interesse em vista da redução da quantidade de água retirada dos mananciais e sua preservação, evitando-se a contaminação dos corpos hídricos, normalmente receptores destes esgotos. Objetivou-se neste trabalho a avaliação dos parâmetros físico- químicos de um latossolo vermelho-amarelo distrófico após a aplicação de água de reúso. Assim, foram realizados dois experimentos: o primeiro em laboratório, onde em uma coluna de solo foram aplicados primeiramente 15L de água destilada; logo em seguida mais 15L de água de reúso proveniente de uma estação de tratamento, por leitos cultivados, de efluente doméstico. A cada 5L de cada água foi coletada amostra da água lixiviada para análises. O segundo experimento foi realizado em uma condição de casa de vegetação onde foram cultivados dois ciclos da alface crespa (Lactuca sativa, L) com 2 tratamentos com 3 repetições cada: testemunhas (Tst1, Tst2 e Tst3), com aplicação de água direta do manancial; e reúso (RsA, RsB e Rsc), proveniente de um sistema fossa filtro composto de um tanque séptico seguido de um filtro anaeróbio. Os resultados mostraram que em ambos os experimentos houve redução em alguns atributos químicos de fertilidade indicando uma possível retenção pelo solo ou pela cultura, ou pela lixiviação. Houve diminuição da condutividade hidráulica do solo, e aumento da condutividade elétrica do extrato de saturação do solo. Notou-se também uma redução do pH do solo e aumento de valores de manganês, além do aumento dos valores da Relação de Adsorção de Sódio (RAS) e Porcentagem de Sódio Trocável (PST). Desta forma pode-se concluir que a utilização de água de reúso para fins agronômicos deve ser de forma racional, monitorando-se principalmente a elevação do teor de sais no solo.Abstract: The use of treated sewage effluent to save the ponds used for irrigation has been of great interest in agriculture, and the unregulated use of this practice can cause changes in physical and chemical behavior of the soil. This practice has been of great interest in view of reducing the quantity of water withdrawal from the springs and its preservation, avoiding the contamination of water bodies, these receptors normally drains. The objective of this work is to evaluate the physical and chemical parameters of a Red-yellow dystrophic Latosol after the implementation of water reuse. Thus, two experiments were conducted: the first in the laboratory, where in a column of soil were applied first 15L of distilled water, then more 15L of water reuse from a wetland treatement for domestic sewage. In each 5L of water application a sample of the water passed throught the columm was collected for analysis. The second experiment was conducted in a condition of a greenhouse where they were grown two rounds of curly lettuce (Lactuca sativa, L) with 2 treatments with 3 repetitions each: witnesses(Tst1, Tst2 and Tst3) and reuse (RSA, RSB and RSC ). The results showed that in both experiments there were decreased in some chemical parameters of fertility indicating a possible retention by ground or by culture. There was a decline in hydraulic conductivity of soil and increase the electrical conductivity of soil saturation extract. It also noted a reduction of the soil pH and increases the values of manganese, in addition to increasing the values of SAR and ESP. Thus we can conclude that the application of water reuse on the soil for agricultural purposes should be in a rational way, and the elevation of salts in the soil must be monitored

    Attenuation coefficient in the energy range 14-36 {keV} of 3D printing materials for physical breast phantoms

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    Objective. To measure the monoenergetic x-ray linear attenuation coefficient, μ, of fused deposition modeling (FDM) colored 3D printing materials (ABS, PLAwhite, PLAorange, PET and NYLON), used as adipose, glandular or skin tissue substitutes for manufacturing physical breast phantoms. Approach. Attenuation data (at 14, 18, 20, 24, 28, 30 and 36 keV) were acquired at Elettra synchrotron radiation facility, with step-wedge objects, using the Lambert–Beer law and a CCD imaging detector. Test objects were 3D printed using the Ultimaker 3 FDM printer. PMMA, Nylon-6 and high-density polyethylene step objects were also investigated for the validation of the proposed methodology. Printing uniformity was assessed via monoenergetic and polyenergetic imaging (32 kV, W/Rh). Main results. Maximum absolute deviation of μ for PMMA, Nylon-6 and HD-PE was 5.0%, with reference to literature data. For ABS and NYLON, μ differed by less than 6.1% and 7.1% from that of adipose tissue, respectively; for PET and PLAorange the difference was less than 11.3% and 6.3% from glandular tissue, respectively. PLAorange is a good substitute of skin (differences from −9.4% to +1.2%). Hence, ABS and NYLON filaments are suitable adipose tissue substitutes, while PET and PLAorange mimick the glandular tissue. PLAwhite could be printed at less than 100% infill density for matching the attenuation of glandular tissue, using the measured density calibration curve. The printing mesh was observed for sample thicknesses less than 60 mm, imaged in the direction normal to the printing layers. Printing dimensional repeatability and reproducibility was less 1%. Significance. For the first time an experimental determination was provided of the linear attenuation coefficient of common 3D printing filament materials with estimates of μ at all energies in the range 14–36 keV, for their use in mammography, breast tomosynthesis and breast computed tomography investigations

    Mudanças nas características físico-químicas de um latossolo vermelho-amarelo distrófico após a irrigação com água de reúso na cultura da alface-crespa (Lactuca sativa, L.)

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    A utilização do efluente de esgoto tratado para poupar os corpos d'água utilizados para irrigação tem sido de grande interesse na agricultura, e o uso não regulamentado desta prática pode acarretar mudanças no comportamento físico-químico do solo. Sua prática tem sido de grande interesse em vista da redução da quantidade de água retirada dos mananciais, preservando-os. Objetivou-se, neste trabalho, a avaliação dos atributos físico-químicos de um Latossolo Vermelho-Amarelo após aplicação de água de reúso. O experimento foi realizado em uma condição de casa de vegetação onde foram cultivados dois ciclos da alface-crespa (Lactuca sativa, L) com dois tratamentos, com três repetições cada: testemunhas (água de abastecimento proveniente de poço) e reúso (proveniente de esgoto local). Os resultados mostraram que não ocorreram aumentos em alguns atributos químicos de fertilidade, como ferro, magnésio, zinco, boro, potássio, nitrato, sódio e cálcio; decréscimo nos valores de matéria orgânica e manganês, além de diminuição da condutividade hidráulica e aumento na condutividade elétrica do solo. Observou-se, ainda, redução do pH no solo, além do aumento da RAS e PST. Desta forma, concluiu-se que a utilização de água de reúso para fins agronômicos deve ser de forma racional, monitorando-se, principalmente, a elevação do teor de sais no solo

    Dataset of patient-derived digital breast phantoms for in-silico studies in breast computed tomography, digital breast tomosynthesis and digital mammography

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    Purpose To present a dataset of computational digital breast phantoms derived from high-resolution 3D clinical breast images for the use in virtual clinical trials in 2D and 3D x-ray breast imaging. Acquisition and validation methods Uncompressed computational breast phantoms for investigations in dedicated breast CT (BCT) were derived from 150 clinical 3D breast images acquired via a BCT scanner at UC Davis (California, USA). Each image voxel was classified in one out of the four main materials presented in the field of view: fibro-glandular tissue, adipose tissue, skin tissue and air. For the image classification, a semi-automatic software was developed. The semi-automatic classification was compared via manual glandular classification performed by two researchers. A total of 60 compressed computational phantoms for virtual clinical trials in digital mammography (DM) and digital breast tomosynthesis (DBT) were obtained from the corresponding uncompressed phantoms via a software algorithm simulating the compression and the elastic deformation of the breast, using the tissue's elastic coefficient. This process was evaluated in terms of glandular fraction modification introduced by the compression procedure. The generated cohort of 150 uncompressed computational breast phantoms presented a mean value of the glandular fraction by mass of 12.3%; the average diameter of the breast evaluated at the center of mass was 105 mm. Despite the slight differences between the two manual segmentations, the resulting glandular tissue segmentation did not consistently differ from that obtained via the semi-automatic classification. The difference between the glandular fraction by mass before and after the compression was 2.1% on average. The 60 compressed phantoms presented an average glandular fraction by mass of 12.1% and an average compressed thickness of 61 mm. Data format and access The generated digital breast phantoms are stored in DICOM files. Image voxels can present one out of four values representing the different classified materials: 0 for the air, 1 for the adipose tissue, 2 for the glandular tissue and 3 for the skin tissue. The generated computational phantoms datasets were stored in the Zenodo public repository for research purposes (http://doi.org/10.5281/zenodo.4529852, http://doi.org/10.5281/zenodo.4515360). Potential applications The dataset developed within the INFN AGATA project will be used for developing a platform for virtual clinical trials in x-ray breast imaging and dosimetry. In addition, they will represent a valid support for introducing new breast models for dose estimates in 2D and 3D x-ray breast imaging and as models for manufacturing anthropomorphic physical phantoms

    Causes for the underreporting of adverse drug events by health professionals: a systematic review

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    Objective: Identifying the main causes for underreporting of Adverse Drug Reaction (ADR) by health professionals. Method: A systematic review carried out in the following databases: LILACS, PAHO, SciELO, EMBASE and PubMed in the period between 1992 and 2012. Descriptors were used in the search for articles, and the identified causes of underreporting were analyzed according to the classification of Inman. Results: In total, were identified 149 articles, among which 29 were selected. Most studies were carried out in hospitals (24/29) for physicians (22/29), and pharmacists (10/29). The main causes related to underreporting were ignorance (24/29), insecurity (24/29) and indifference (23/29). Conclusion: The data show the eighth sin in underreporting, which is the lack of training in pharmacovigilance. Therefore, continuing education can increase adherence of professionals to the service and improve knowledge and communication of risks due to drug use.Objetivo: Identificar as causas de subnotificação de Reação Adversa a Medicamento (RAM) por profissionais da saúde. Método: Revisão sistemática realizada nas bases de dados LILACS, PAHO, SciELO, EMBASE e PubMed, cujo período de abrangência foi de 1992 a 2012. Foram utilizados descritores para buscar os artigos. As causas de subnotificação de RAM identificadas foram analisadas de acordo com a classificação de Inman. Resultados: Identificaram-se 149 artigos, dos quais 29 foram considerados elegíveis. A maioria dos estudos foi conduzida em hospitais (24/29), para mé- dicos (22/29) e farmacêuticos (10/29). As principais causas relacionadas à subnotificação observadas foram: a ignorância (24/29), a insegurança (24/29) e a indiferença (23/29). Conclusão: Os dados evidenciam o oitavo pecado da subnotifica- ção, que é a falta de formação em farmacovigilância. Assim, a educação permanente pode aumentar a adesão dos profissionais ao serviço e melhorar o conhecimento e a comunicação dos riscos associados ao uso de medicamentosObjetivo: Identificar as causas de subnotificação de Reação Adversa a Medicamento (RAM) por profissionais da saúde. Método: Revisão sistemática realizada nas bases de dados LILACS, PAHO, SciELO, EMBASE e PubMed, cujo período de abrangência foi de 1992 a 2012. Foram utilizados descritores para buscar os artigos. As causas de subnotificação de RAM identificadas foram analisadas de acordo com a classificação de Inman. Resultados: Identificaram-se 149 artigos, dos quais 29 foram considerados elegíveis. A maioria dos estudos foi conduzida em hospitais (24/29), para médicos (22/29) e farmacêuticos (10/29). As principais causas relacionadas à subnotificação observadas foram: a ignorância (24/29), a insegurança (24/29) e a indiferença (23/29). Conclusão: Os dados evidenciam o oitavo pecado da subnotificação, que é a falta de formação em farmacovigilância. Assim, a educação permanente pode aumentar a adesão dos profissionais ao serviço e melhorar o conhecimento e a comunicação dos riscos associados ao uso de medicamentos.

    Fabrication of 3D printed patient-derived anthropomorphic breast phantoms for mammography and digital breast tomosynthesis: Imaging assessment with clinical X-ray spectra

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    Purpose: To design, fabricate and characterize 3D printed, anatomically realistic, compressed breast phantoms for digital mammography (DM) and digital breast tomosynthesis (DBT) x-ray imaging. Materials: We realized 3D printed phantoms simulating healthy breasts, via fused deposition modeling (FDM), with a layer resolution of 0.1 mm and 100% infill density, using a dual extruder printer. The digital models were derived from a public dataset of segmented clinical breast computed tomography scans. Three physical phantoms were printed in polyethylene terephthalate (PET), acrylonitrile–butadiene–styrene (ABS), or in polylactic-acid (PLA) materials, using ABS as a substitute for adipose tissue, and PLA or PET filaments for replicating glandular and skin tissues. 3D printed phantoms were imaged at three clinical centers with DM and DBT scanners, using typical spectra. Anatomical noise of the manufactured phantoms was evaluated via the estimates of the β parameter both in DM images and in images acquired via a clinical computed tomography (CT) scanner. Results: DM and DBT phantom images showed an inner texture qualitatively similar to the images of a clinical DM or DBT exam, suitably reproducing the glandular structure of their computational phantoms. β parameters evaluated in DM images of the manufactured phantoms ranged between 2.84 and 3.79; a lower β was calculated from the CT scan. Conclusions: FDM 3D printed compressed breast phantoms have been fabricated using ABS, PLA and PET filaments. DM and DBT images with clinical x-ray spectra showed realistic textures. These phantoms appear promising for clinical applications in quality assurance, image quality and dosimetry assessments

    Alterações nos atributos de um Latossolo Vermelho-amarelo irrigado com água de reúso Alterations in attributes of a Red-yellow Latosol irrigated with reuse water

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    A reutilização do efluente de esgoto tratado para suprir a falta de fontes d'água para irrigação tem sido de grande interesse para a agricultura e o uso desta prática, se não regulamentado, pode acarretar em mudanças no comportamento físico e químico do solo. Objetivou-se, neste trabalho, a avaliação das alterações dos atributos físico-químicos de um Latossolo Vermelho amarelo, após a aplicação da água de reúso proveniente de uma estação de tratamento de efluentes por leitos cultivados. Um experimento em coluna de solo foi realizado em laboratório; 15 L de água destilada lhe foram aplicados e, logo após, mais 15 L de água de reúso e, a cada 5 L, foi coletada amostra da água lixiviada para análises. Os resultados mostraram, após a aplicação no solo, da água de reúso, redução de nitrato, potássio e valores da condutividade hidráulica saturada e aumento das concentrações de sódio, ferro, manganês, zinco e condutividade elétrica. Pode-se concluir, desta forma, que a utilização de água de reúso para fins agronômicos deve ser de forma racional, monitorando-se principalmente a elevação do teor do íon sódio.<br>The reuse of treated sewage effluent to water bodies to supply water for irrigation has been of great advantage to agriculture, and the use if not regimented could bring changes in physical and chemical properties of soil. This paper aimed the evaluation of the physical and chemical properties alteration of a Red-yellow Latosol after the application of reuse water from an effluent treatment station of wetlands. The experiment was accomplished in laboratory using a soil column. First, 15 L of distilled water were applied in the soil column and after 15 L of reuse water and at interval of 5 L of water a sample was collected for analysis. The results showed decrease of nitrate, potassium and saturated hydraulic conductivity values and an increase in sodium, iron, manganese, zinc and electrical conductivity of the soil after water application. In this way, it may be concluded that the use of waste water for agronomic activities must be used in a rational way, mainly checking the elevation of sodium
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