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3.
Med Phys ; 50(11): 6639-6648, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37706560

RESUMO

BACKGROUND: In recent years, deep-learning models have been used to predict entire three-dimensional dose distributions. However, the usability of dose predictions to improve plan quality should be further investigated. PURPOSE: To develop a deep-learning model to predict high-quality dose distributions for volumetric modulated arc therapy (VMAT) plans for patients with gynecologic cancer and to evaluate their usability in driving plan quality improvements. METHODS: A total of 79 VMAT plans for the female pelvis were used to train (47 plans), validate (16 plans), and test (16 plans) 3D dense dilated U-Net models to predict 3D dose distributions. The models received the normalized CT scan, dose prescription, and target and normal tissue contours as inputs. Three models were used to predict the dose distributions for plans in the test set. A radiation oncologist specializing in the treatment of gynecologic cancers scored the test set predictions using a 5-point scale (5, acceptable as-is; 4, prefer minor edits; 3, minor edits needed; 2, major edits needed; and 1, unacceptable). The clinical plans for which the dose predictions indicated that improvements could be made were reoptimized with constraints extracted from the predictions. RESULTS: The predicted dose distributions in the test set were of comparable quality to the clinical plans. The mean voxel-wise dose difference was -0.14 ± 0.46 Gy. The percentage dose differences in the predicted target metrics of D 1 % ${D}_{1{\mathrm{\% }}}$ and D 98 % ${D}_{98{\mathrm{\% }}}$ were -1.05% ± 0.59% and 0.21% ± 0.28%, respectively. The dose differences in the predicted organ at risk mean and maximum doses were -0.30 ± 1.66 Gy and -0.42 ± 2.07 Gy, respectively. A radiation oncologist deemed all of the predicted dose distributions clinically acceptable; 12 received a score of 5, and four received a score of 4. Replanning of flagged plans (five plans) showed that the original plans could be further optimized to give dose distributions close to the predicted dose distributions. CONCLUSIONS: Deep-learning dose prediction can be used to predict high-quality and clinically acceptable dose distributions for VMAT female pelvis plans, which can then be used to identify plans that can be improved with additional optimization.


Assuntos
Aprendizado Profundo , Neoplasias , Radioterapia de Intensidade Modulada , Humanos , Feminino , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Órgãos em Risco
4.
Front Oncol ; 13: 1204323, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37771435

RESUMO

Purpose: Variability in contouring structures of interest for radiotherapy continues to be challenging. Although training can reduce such variability, having radiation oncologists provide feedback can be impractical. We developed a contour training tool to provide real-time feedback to trainees, thereby reducing variability in contouring. Methods: We developed a novel metric termed localized signed square distance (LSSD) to provide feedback to the trainee on how their contour compares with a reference contour, which is generated real-time by combining trainee contour and multiple expert radiation oncologist contours. Nine trainees performed contour training by using six randomly assigned training cases that included one test case of the heart and left ventricle (LV). The test case was repeated 30 days later to assess retention. The distribution of LSSD maps of the initial contour for the training cases was combined and compared with the distribution of LSSD maps of the final contours for all training cases. The difference in standard deviations from the initial to final LSSD maps, ΔLSSD, was computed both on a per-case basis and for the entire group. Results: For every training case, statistically significant ΔLSSD were observed for both the heart and LV. When all initial and final LSSD maps were aggregated for the training cases, before training, the mean LSSD ([range], standard deviation) was -0.8 mm ([-37.9, 34.9], 4.2) and 0.3 mm ([-25.1, 32.7], 4.8) for heart and LV, respectively. These were reduced to -0.1 mm ([-16.2, 7.3], 0.8) and 0.1 mm ([-6.6, 8.3], 0.7) for the final LSSD maps during the contour training sessions. For the retention case, the initial and final LSSD maps of the retention case were aggregated and were -1.5 mm ([-22.9, 19.9], 3.4) and -0.2 mm ([-4.5, 1.5], 0.7) for the heart and 1.8 mm ([-16.7, 34.5], 5.1) and 0.2 mm ([-3.9, 1.6],0.7) for the LV. Conclusions: A tool that uses real-time contouring feedback was developed and successfully used for contour training of nine trainees. In all cases, the utility was able to guide the trainee and ultimately reduce the variability of the trainee's contouring.

5.
Diagnostics (Basel) ; 13(4)2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36832155

RESUMO

Developers and users of artificial-intelligence-based tools for automatic contouring and treatment planning in radiotherapy are expected to assess clinical acceptability of these tools. However, what is 'clinical acceptability'? Quantitative and qualitative approaches have been used to assess this ill-defined concept, all of which have advantages and disadvantages or limitations. The approach chosen may depend on the goal of the study as well as on available resources. In this paper, we discuss various aspects of 'clinical acceptability' and how they can move us toward a standard for defining clinical acceptability of new autocontouring and planning tools.

6.
Pract Radiat Oncol ; 13(3): e282-e291, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36697347

RESUMO

PURPOSE: This study aimed to use deep learning-based dose prediction to assess head and neck (HN) plan quality and identify suboptimal plans. METHODS AND MATERIALS: A total of 245 volumetric modulated arc therapy HN plans were created using RapidPlan knowledge-based planning (KBP). A subset of 112 high-quality plans was selected under the supervision of an HN radiation oncologist. We trained a 3D Dense Dilated U-Net architecture to predict 3-dimensional dose distributions using 3-fold cross-validation on 90 plans. Model inputs included computed tomography images, target prescriptions, and contours for targets and organs at risk (OARs). The model's performance was assessed on the remaining 22 test plans. We then tested the application of the dose prediction model for automated review of plan quality. Dose distributions were predicted on 14 clinical plans. The predicted versus clinical OAR dose metrics were compared to flag OARs with suboptimal normal tissue sparing using a 2 Gy dose difference or 3% dose-volume threshold. OAR flags were compared with manual flags by 3 HN radiation oncologists. RESULTS: The predicted dose distributions were of comparable quality to the KBP plans. The differences between the predicted and KBP-planned D1%,D95%, and D99% across the targets were within -2.53% ± 1.34%, -0.42% ± 1.27%, and -0.12% ± 1.97%, respectively, and the OAR mean and maximum doses were within -0.33 ± 1.40 Gy and -0.96 ± 2.08 Gy, respectively. For the plan quality assessment study, radiation oncologists flagged 47 OARs for possible plan improvement. There was high interphysician variability; 83% of physician-flagged OARs were flagged by only one of 3 physicians. The comparative dose prediction model flagged 63 OARs, including 30 of 47 physician-flagged OARs. CONCLUSIONS: Deep learning can predict high-quality dose distributions, which can be used as comparative dose distributions for automated, individualized assessment of HN plan quality.


Assuntos
Aprendizado Profundo , Radioterapia de Intensidade Modulada , Humanos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Órgãos em Risco , Radioterapia de Intensidade Modulada/métodos
7.
Rev. medica electron ; 43(3): 872-878, 2021. tab, graf
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1289825

RESUMO

RESUMEN La formación de un médico de nuevo modelo en Cuba surge de forma experimental por la necesidad que tenía la población de recibir una atención médica integral. Como siempre nuestro comandante con sus ideas revolucionarias plantea la necesidad de su creación para que cada familia cubana contara con un médico y una enfermera que les brindara apoyo y cuidado desde el punto de vista clínico, epidemiológico y social. El municipio de Colón fue el primero en implementar este novedoso programa en la provincia de Matanzas. Con el objetivo de dar a conocer el surgimiento y desarrollo del mismo en esta ciudad es que se realiza el siguiente trabajo (AU).


SUMMARY The training of a new model doctor in Cuba arises experimentally because of the need of the population to receive comprehensive medical care. As always, our commander with his revolutionary ideas raised the need for its creation so that each Cuban family would have a doctor and a nurse who could provide support and care from a clinical, epidemiological and social point of view. The municipality of Colón was the first to implement this novel program in the province of Matanzas. With the aim of publicizing its emergence and development in our city, the authors wrote the following article (AU).


Assuntos
Humanos , Masculino , Feminino , Medicina de Família e Comunidade/história , História da Medicina , Médicos de Família/educação , Médicos de Família/história , Capacitação Profissional , Medicina de Família e Comunidade/educação , Medicina de Família e Comunidade/métodos , Enfermeiros de Saúde da Família/educação , Enfermeiros de Saúde da Família/história
8.
rev cuba genet comunit ; 13(2): 01-17, 2020. ilus, graf
Artigo em Espanhol | CUMED | ID: cum-79284

RESUMO

Introducción: Entre el 25 50 (percent) de todos los cromosomas marcadores supernumerarios provienen del cromosoma 15, la mayoría se identifican como una inversión duplicación del 15 (inv dup 15).Objetivos: Describir tres casos de pacientes portadores de un marcador cromosómico de inv dup (15), detectados de manera diferente, que son remitidos al laboratorio de citogenética del Centro Nacional de Genética Médica de la Habana por causas disimiles.Métodos: Los análisis citogenéticos convencionales en sangre y líquido amniótico fueron realizados por el método estandarizado en el laboratorio basándonos en los protocolos de las guías internacionales del Cytogenetics Laboratory Manual. Para los análisis mediante citogenética molecular se utilizaron sondas VYSIS, de ABBOT específicamente la sonda: LSI SRNPN spectrum green/CEP 15(D15Z1) spectrum red/ LSI PML spectrum orange u otra variante de esta sonda con LSI SRNPN spectrum orange/CEP 15(D15Z1) spectrum green/ LSI PML spectrum Orange.Resultados: El caso I, es detectado prenatalmente mediante una prueba de hibridación fluorescente in situ (FISH por sus siglas en ingles) en células en interfase, presenta una inv dup15 que incluye la región 15q11.2-q13. No se presentan anomalías ecográficas fetales. La pareja decide continuar la gestación. La niña actualmente tiene retardo psico-motor.Caso II, es detectada la inv dup 15 en niña de seis años, con espectro autista y discapacidad intelectual. El marcador incluye la región 15q11.2-q13.Caso III, el cromosoma marcador es detectado en mujer de inteligencia normal con abortos espontáneos a repetición. La inv dup del 15 se extiende desde el centrómero hasta la región 15q11.1.Conclusiones: Las implicaciones en el fenotipo de los individuos, con un marcador supernumerario de inv dup 15, están dadas por la inclusión o no de la zona crítica de los sín...(AU)


Assuntos
Humanos , Masculino , Feminino , Cromossomos , Cromossomos/genética
9.
Rev. medica electron ; 35(6)nov.-dic. 2013. ilus
Artigo em Espanhol | CUMED | ID: cum-55730

RESUMO

En un artículo publicado anteriormente se había abordado la historia de la salud en el municipio Colón en la etapa colonial. En este trabajo se realiza una reseña histórica sobre el desarrollo de la salud pública en la ciudad en la etapa neocolonial, tomando como punto de partida la importancia del conocimiento de la historia local y más específicamente en la rama de la salud pública(AU)


In an article published before, we dealt with the health care history in the municipality of Colon during the colonial period. In this work we make a historical review on the development of public health in the city in the neo-colonial period, setting as starting point the importance of local history knowledge and specifically the history of public health(AU)


Assuntos
Humanos , História do Século XX , História do Século XX , História da Medicina , Cuba
10.
Rev. medica electron ; 34(3)mayo-jun. 2012. ilus
Artigo em Espanhol | CUMED | ID: cum-51395

RESUMO

Para llegar a ser un verdadero profesional de la salud, es preciso, además de tener dominio pleno de la rama de las ciencias médicas en la que se desempeñe, conocer la historia y los antecedentes de la misma, fundamentalmente la de la localidad en que se vive. Se realizó una breve reseña sobre el surgimiento y desarrollo de la salud pública en el municipio Colón, durante la etapa colonial. Para ello se tomó como punto de partida la importancia que tiene para el hombre conocer sus raíces y tradiciones(AU)


To become a real healths professional, is necessary, apart from having a whole dominion of the branch of the medical science in which may be play to have a good knowledge of the history and the previous deeds from itself, fundamentally about the history of the area in which one lives. A brief study was made about the beginning and development of the public health in the municipality of Colón in the colonial period. Thats why it was taken as point of start the importance that it has for the mankind to know their traditions and its beginnings(AU)


Assuntos
História do Século XIX , História da Medicina
11.
Recurso na Internet em Espanhol | LIS - Localizador de Informação em Saúde | ID: lis-12483

RESUMO

Presenta orientaciones para el manejo de pacientes que requieren cuidados paliativos y de aquellas enfermedades que requieren control del dolor y cuidados relacionados con el progreso de la enfermedad y los tratamientos. Aborda algunos temas como la analgesia, principios éticos relevantes a la medicina paliativa y la comunicación con la familia del paciente terminal. Documento en formato PDF, requiere Acrobat Reader.


Assuntos
Cuidados Paliativos , Cuidados Paliativos , Analgesia , Doente Terminal
12.
Arch. venez. farmacol. ter ; 18(1): 37-38, 1999. tab
Artigo em Espanhol | LILACS | ID: lil-325668

RESUMO

Se estudiaron 24 pacientes, 22 de los cuales sufrían algun tipo de neuritis. Se trataron con una mezcla de ACELTISALICILATO de LISINA y Vitaminas B1, B6, B12 incorporadas al solvente para diluir el analgésico. Diecisiete pacientes mejoraron entre un 80 y 100 por ciento de su dolor valorado con una escala gráfica de 1 a 10, o sea que el 70,83 por ciento de los pacientes obtuvieron una respuesta analgésica satisfactoria con minimos efectos secundarios que describieron los pacientes como un ligero dolor en el sitio de la inyecci¢n. A todos los pacientes se les administró una ampolla con la mezcla cada 24 horas, por vía intramuscular profunda, durante 4 días consecutivos


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Aspirina , Lisina , Neurite (Inflamação) , Piridoxina , Tiamina , Vitamina B 12 , Medicina , Farmacologia , Venezuela
16.
Rev. venez. anestesiol ; 2(1): 13-7, ene.-jun. 1997. tab, graf
Artigo em Espanhol | LILACS | ID: lil-263237

RESUMO

Uno de los cuatro componentes del programa de control del cáncer de la Organización Mundial de la Salud (OMS) es el tratamiento del dolor asociado al cáncer y las restricciones gubernamentales con respecto aluso de opioides, constituye uno de los obstáculos de este programa. Con la idea de identificar las barreras en nuestro país se realizó este estudio para comparar las dosis recomendadas de opioides por la Asociación Internacional para el estudio del dolor (IASP) y las dosis permitidas por el Ministerio de Sanidad y Asistencia Social (MSAS) en Venezuela. Los datos fueron obtenidos de la Gaceta Oficial y del Task Force on Acute Pain de la IASP y se observó que todas las dosis permitidas de opioides por el MSAS en Venezuela se escuentran entre un 40 por ciento y 75 por ciento de las dosis recomendadas (IASP), con un menor porcentaje para la morfina, a pesar de ser este analgésico indicador de un buen tratamiento del dolor por cáncer. Sin embargo estas restricciones gubernamentales fueron modificadas y los médicos tratantes pueden aumentar las dosis si hacen un informe médico que lo justifique. La gaceta oficial no determina las dosis por vía oral ni parental de algunos opioides disponibles en el país


Assuntos
Humanos , Masculino , Feminino , Dor/patologia , Dor/terapia , Dextropropoxifeno/administração & dosagem , Posologia Homeopática , Morfina , Neoplasias/diagnóstico , Neoplasias/terapia , Entorpecentes/administração & dosagem , Entorpecentes/uso terapêutico , Venezuela
17.
Arch. venez. farmacol. ter ; 13(2): 132-4, 1994. tab, graf
Artigo em Espanhol | LILACS | ID: lil-238590

RESUMO

En un estudio simple ciego se estudió la eficiencia y tolerancia de un nuevo preparado a base de acetilsalicilato de lisina y pridinol mesilato en 56 pacientes que recibieron una dosis diaria del producto, por vía intramuscular, durante 5 días y que presentaban dolor y contractura muscular de diferentes localizaciones. Se obtuvieron buenos resultados en el 83.93 por ciento de los pacientes tratados, regulares en el 7,14 por ciento y solo hubo un 8,93 por ciento donde los resultados fueron nulos. En los pacientes que respondieron positivamente el comienzo de la acción analgésica fue rápido, pues ya desde la primera inyección se observó una franca mejoría del dolor. No se observaron efectos secundarios en ninguno de los pacientes tratados, salvo un ligero dolor moméntáneo en el sitio de la inyección en algunos pacientes


Assuntos
Humanos , Analgésicos/administração & dosagem , Lisina/administração & dosagem , Músculos/anormalidades , Dor/classificação , Relaxamento Muscular/genética
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