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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
561

Comparação da técnica de radioterapia em arco modulada volumetricamente (VMAT) em relação à técnica de radioterapia de intensidade modulada (IMRT) para tumores de próstata e cabeça e pescoço / Volumetric modulated arc therapy (VMAT) and intensity modulated radiotherapy (IMRT) techniques comparison for prostate and head and neck tumors

Érika Yumi Watanabe 12 January 2016 (has links)
As técnicas de radioterapia vem sendo constantemente modificadas com a implementação de novas tecnologias visando aumentar a eficiência e diminuir a toxicidade dos tratamentos com radiação ionizante. Esse trabalho visa comparar as técnicas de radioterapia de intensidade modulada (IMRT) e a radioterapia em arco modulada volumetricamente (VMAT) em termos dosimétricos para o alvo e órgãos em risco além de avaliar a diferença do tempo de tratamento utilizando cada técnica. Para assegurar que os planejamentos seguiriam um padrão aceitável para ambas as técnicas, realizou-se primeiramente os planejamentos sugeridos pelo TG 119 da Associação Americana de Física Médica e compatibilidade dos resultados obtidos comparados com os dados da literatura. Tal comparação permitiu prosseguir para uma próxima etapa que consistiu da utilização de imagens de pacientes reais que foram submetidos a tratamentos de próstata e cabeça e pescoço, para a realização dos planejamentos utilizando as técnicas de IMRT e VMAT. A qualidade dosimétrica dos planejamentos utilizando ambas as técnicas foi avaliada em termos de conformidade e homogeneidade da dose no alvo e para os casos de pacientes com câncer de próstata, foram investigados os limites de dose em reto, bexiga e cabeça de fêmur, sendo avaliada a associação entre o volume de intersecção de reto e bexiga com o alvo. Para os   casos de pacientes com câncer de cabeça e pescoço, em termos dos limites de dose em medula, tronco cerebral e parótidas. Os planejamentos nos quais fez se uso da técnica de VMAT apresentaram valores semelhantes aos dos planos de IMRT. A análise dos tempos de tratamento para cada técnica avaliada mostrou que a VMAT reduz significativamente o tempo, até 67% para os casos de pacientes com câncer de próstata e até 36% para os casos de pacientes com câncer de cabeça e pescoço / The goal of this study was to compare the dosimetric aspects of volumetric-modulated arc therapy (VMAT) with those of intensity-modulated radiotherapy (IMRT) and to evaluate the delivery time and monitor unit differences between the two techniques, for applications in prostate and head and neck cancer treatment. First of all, to assure an acceptable pattern of treatment planning using both techniques, the TG119 of American Association of Medical Physics instructions were followed and the results of plans were compared to TG119 published data. The next step consisted of using real patients\' images, whose underwent prostate radiotherapy or head and neck radiotherapy, to planning IMRT and VMAT. The dosimetric quality of plans using both techniques was evaluated in terms of target dose conformity and target dose homogeneity The dose constraints for rectum, bladder and femoral head were analyzed and the association between the rectum intersection volume and bladder intersection volume to the target volume were evaluated for the prostate cases. The dose constraints for spinal cord, brainstem and parotids were investigated for the head and neck cases. Best or similar values were obtained for the VMAT plans in relation to IMRT plans. The analysis of treatment time indicated a significant reduction using VMAT, until 67% to the prostate cases and 36% to the head and neck cases
562

Hierarchical neuropsychological functioning in pediatric survivors of acute lymphoblastic leukemia.

Larery, Angela R. D. 08 1900 (has links)
Acute lymphocytic leukemia (ALL) is one of the most common types of pediatric cancers. Improvements in treatment within the last 20 years have resulted in reduced mortality and a greater focus upon quality of life. Several researchers have documented neuropsychological impairments in children following treatment for ALL; however, there have not been any comparative studies documenting differences in neuropsychological functioning based upon treatment modality despite the documented effects of radiation therapy and combined radiation/chemotherapy upon the developing brain. In addition, past studies have focused on unitary measures, ignoring the hierarchical relationship between basic cognitive functions and more abstract skills. This study examined the neuropsychological functioning of 81 children who were treated for ALL at a metropolitan children's hospital. All children were tested a minimum of two years after the final treatment session and were administered the NEPSY. Results do not support any interactions or main effects with the exception of the age of the child at diagnosis. Children diagnosed prior to the age of 5 showed greater impairments on tasks measuring attention, memory, and visuospatial reasoning in comparison to peers diagnosed after age 6.
563

Improvements in 3D breast treatment plan quality and efficiency through computer automation of tangential breast radiotherapy treatment plans

Gibbs, Jacob M. 15 June 2023 (has links)
No description available.
564

Knowledge-based IMRT treatment planning for prostate cancer.

Chanyavanich, V, Das, SK, Lee, WR, Lo, JY 05 1900 (has links)
PURPOSE: To demonstrate the feasibility of using a knowledge base of prior treatment plans to generate new prostate intensity modulated radiation therapy (IMRT) plans. Each new case would be matched against others in the knowledge base. Once the best match is identified, that clinically approved plan is used to generate the new plan. METHODS: A database of 100 prostate IMRT treatment plans was assembled into an information-theoretic system. An algorithm based on mutual information was implemented to identify similar patient cases by matching 2D beam's eye view projections of contours. Ten randomly selected query cases were each matched with the most similar case from the database of prior clinically approved plans. Treatment parameters from the matched case were used to develop new treatment plans. A comparison of the differences in the dose-volume histograms between the new and the original treatment plans were analyzed. RESULTS: On average, the new knowledge-based plan is capable of achieving very comparable planning target volume coverage as the original plan, to within 2% as evaluated for D98, D95, and D1. Similarly, the dose to the rectum and dose to the bladder are also comparable to the original plan. For the rectum, the mean and standard deviation of the dose percentage differences for D20, D30, and D50 are 1.8% +/- 8.5%, -2.5% +/- 13.9%, and -13.9% +/- 23.6%, respectively. For the bladder, the mean and standard deviation of the dose percentage differences for D20, D30, and D50 are -5.9% +/- 10.8%, -12.2% +/- 14.6%, and -24.9% +/- 21.2%, respectively. A negative percentage difference indicates that the new plan has greater dose sparing as compared to the original plan. CONCLUSIONS: The authors demonstrate a knowledge-based approach of using prior clinically approved treatment plans to generate clinically acceptable treatment plans of high quality. This semiautomated approach has the potential to improve the efficiency of the treatment planning process while ensuring that high quality plans are developed. / Dissertation
565

Comparação dosimétrica 3D de tratamentos de câncer de mama com técnica conformacional 3D usando filtros e com IMRT direto e inverso na presença do movimento respiratório / 3D dosimetric comparison of breast cancer treatments with 3D conformational technique using filters and with direct and inverse IMRT in the presence of respiratory movement

Lizar, Jéssica Caroline 03 April 2017 (has links)
A radioterapia externa pós-operatória em mulheres diagnosticadas com câncer de mama em estágio inicial é tido como um procedimento padrão, no entanto durante o planejamento para irradiação do volume alvo as possíveis incertezas dosimétricas introduzidas dado o movimento respiratório intrínseco da paciente são desconsideradas. Este estudo avalia não apenas a influência da respiração na distribuição tridimensional da dose, mas como essa distribuição se modifica dado a técnica radioterápica empregada para o tratamento. Três técnicas de planejamento foram analisadas: a radioterapia conformacional tridimensional (3D-RT) com filtros, a radioterapia com intensidade modulada (IMRT) usando planejamento direto e o IMRT inverso. A fim de simular o movimento de contração e expansão da caixa torácica, utilizou-se uma plataforma com amplitudes de oscilação pré-determinadas, sendo a frequência de oscilação provida por uma fonte de tensão variável. Para simular a mama usou-se objetos simuladores semiesféricos preenchidos com gel dosimétrico (MAGIC-f). Os planejamentos para cada técnica foram realizados sobre a mesma tomografia computadorizada (CT) do objeto simulador preenchido com água no modo estático. Foram produzidos três lotes de dosímetro gel para o projeto, cada lote foi irradiado com uma técnica radioterápica diferente, sendo que cada lote inclui cinco objetos simuladores e um conjunto de nove tubos de calibração preenchidos com gel MAGIC-f. O primeiro dos objetos simuladores é utilizado como referência, o segundo é irradiado no modo estático, os demais são irradiados em diferentes amplitudes, respectivamente: 0,34 cm, 0,88 cm e 1,22 cm. A informação volumétrica de dose foi obtida utilizando imagens por ressonância magnética nuclear (IRMN), para cada lote foram adquiridos IRMN com sequência multi spin echo e os mapas de relaxometria, que são associados à dose, foram extraídos em um software desenvolvido e aprimorado pelo nosso grupo de pesquisa. A comparação quantitativa dos mapas de relaxometria dos objetos simuladores em movimento em relação ao modo estático foi realizado pelo índice gamma tridimensional (3% / 3mm / 15% Threshold). Para o 3D-RT a porcentagem de pontos aprovados do objeto estático em relação ao oscilante na amplitude de 0,34 cm foi de 96,44%, para amplitude de 0,88 cm foi de 93,23% e para amplitude de 1,22 cm foi de 91,65%. Para o IMRT direto a porcentagem de pontos aprovados do objeto estático em relação ao oscilante na amplitude de 0,34 cm foi de 98,42%, para amplitude de 0,88 cm foi de 95,66% e para amplitude de 1,22 cm foi de 94,31%. Para o IMRT inverso a porcentagem de pontos aprovados do objeto estático em relação ao oscilante na amplitude de 0,34 cm foi de 94,49%, para amplitude de 0,88 cm foi de 93,51% e para amplitude de 1,22 cm foi de 86,62%. A partir dos resultados, infere-se que a movimentação respiratória de baixa amplitude, para tratamentos de câncer de mama, não é um fator preocupante para a rotina clínica, porém o aumento da amplitude da oscilação aumenta a inomogeneidade de dose e pode afetar os parâmetros dosimétricos da cobertura do volume alvo em relação ao planejamento do tratamento. Observou-se em conjunto que a distribuição de dose se modifica claramente com a técnica em uso e no caso do IMRT inverso para amplitude de oscilação de 1,22 cm a aprovação no índice gamma foi menor que 90% / External postoperative radiotherapy in women diagnosed with early stage breast cancer is considered as a standard procedure, however during planning for target volume irradiation as possible dosimetric uncertainties reabsorption of the patient\'s intrinsic respiratory movement are disregarded. This study evaluates not only the influence of respiration on the three-dimensional distribution of the dose but how this distribution is modified due to the radiotherapy technique used for treatment. Three planning techniques were analyzed: three-dimensional conformational radiotherapy (3D-RT) with filters, intensity-modulated radiotherapy (IMRT) using direct planning and inverse IMRT. In order to simulate the movement of contraction and expansion of the chest wall, a platform with predetermined oscillation amplitudes was used, the oscillation frequency was provided by a variable voltage source. To simulate the breast, semi-spherical simulator objects filled with dosimetric gel (MAGIC-f) were used. The plannnings for each technique were performed on the computerized tomography (CT) of the simulator object filled with water in static mode. Three batches of gel dosimeters were prepared for the project, each batch was irradiated with a different radiothermic technique and comprised five simulator objects and a set of nine calibration tubes filled with MAGIC-f gel. The first simulator objects is used as reference, the second is irradiated in the static mode, the others are irradiated using different amplitudes, respectively: 0,34 cm, 0,88 cm and 1,22 cm. Volumetric dose information was obtained using Nuclear Magnetic Resonance Imaging, each batch was scanned with a multi spin echo sequence and the dose-related relaxometry maps were extracted in a software developed and improved by our Group of research. The quantitative comparison of the relaxometry maps of the moving simulator objects with respect to the static mode was performed by the three-dimensional gamma index (3% / 3mm / 15% threshold). For the 3D-RT, the percentage of approved points of the static object with respect to the oscillator in the amplitude of 0.34 cm was 96.44%, for amplitude of 0.88 cm was 93.23% and for amplitude of 1.22 cm was 91.65%. For the direct IMRT the percentage of approved points of the static object in relation to the oscillator in the amplitude of 0.34 cm was 98.42%, for amplitude of 0.88 cm was 95.66% and for amplitude of 1.22 cm was 94.31%. For the inverse IMRT, the percentage of approved points of the static object in relation to the oscillator in the amplitude of 0.34 cm was 94.49%, for amplitude of 0.88 cm was 93.51% and for amplitude of 1.22 cm was 86.62%. From the results, it is inferred that a low-amplitude respiratory movement, for breast cancer treatments, is not a worrying factor for clinical routine, however, increasing the amplitude of the oscillation increases the inomogeneity of the dose and this affects the dosimetry parameters of the target volume coverage. It was observed that the dose distribution changes with the technique in use and in the case of the inverse IMRT for amplitude of oscillation of 1.22 cm, less than 90% of points were approved in the gamma index evaluation
566

Feasibility of an educational intervention program on managing the nutrition impact symptom cluster in patients with nasopharyngeal carcinoma during radiotherapy

January 2016 (has links)
"Background: Nasopharyngeal carcinoma (NPC) is endemic in southern China. Despite the improvement in radiotherapy (RT) technology, NPC patients still suffer from numerous and simultaneous distressing symptoms. / Aims: The aim of the study was to explore the feasibility of an intervention program (an educational intervention program) in managing the most distressing symptom cluster (nutrition impact symptom cluster) in NPC patients during RT. / Methods: The study was carried out in two parts. Part I consisted of groundwork research (n = 130) using a cross-sectional design to identify the most distressing symptom cluster. An instrument validation was also conducted at this point. Part II covered the development process and pilot testing of an educational intervention program, guided by the Medical Research Council (MRC) framework, to manage the nutrition impact symptom cluster identified in Part I. First, to inform development of the intervention, a systematic review was conducted to evaluate the effectiveness of psychoeducational intervention (PEI), which includes the educational intervention, in managing symptom clusters in patients with generic cancers. Second, a descriptive qualitative study was conducted through face-to-face semi-structured interviews with 25 NPC patients and 16 health professionals, separately, to provide further help in developing the intervention by investigating patients’ self-care experience and current clinical practice in managing the nutrition impact symptom cluster. Third, the feasibility and estimated effectiveness of the educational intervention program was explored in a pilot randomized controlled trial (RCT) (n = 40). Outcome measures, including severity of the nutrition impact symptom cluster, body weight, functional performance and quality of life (QOL), were assessed at baseline, week 3 of RT and at the end of RT. Inferential statistics, such as independent t-test, Chi-square test, Fisher’s exact test and the generalized estimating equation (GEE) model, were used to compare the baseline and various outcome variables between groups. / Results: In Part I, the Chinese version of the MD Anderson Symptom Inventory - Head and Neck Module (MDASI-HN-C) was found to be a reliable and valid instrument. The same dataset then revealed four symptom clusters in NPC patients during RT; the nutrition impact cluster was identified as the most distressing, and was thus chosen as the target outcome of the intervention. In Part II, the systematic review found that PEI, in particular, patient education, was a promising intervention to manage cancer symptom clusters. Then, the findings of the qualitative study further informed and guided the development of an educational intervention program. The pilot RCT found that the conducting the program in a clinical setting was feasible and well received by patients. It also had some favorable effects on managing the nutrition impact symptom cluster, in terms of relieving the cluster itself (Cohen’s d = -0.37), and improving the physical well-being (Cohen’s d = -0.15) and head and neck cancer (HNC) specific QOL (Cohen’s d = -0.05). / Conclusion: The implementation of the educational intervention program appears to be feasible with NPC patients during RT, showing some effect in improving the nutrition impact symptom cluster. A future full-scale study with an adequate sample is warranted." / 研究背景:鼻咽癌在中國南部高發。儘管放療技術在進步,鼻咽癌病人在接受放療期間仍然存在著各種同時出現的症狀困擾。 / 研究目的:本研究旨在測試一個健康教育干預項目在管理鼻咽癌病人放療期間最嚴重的營養相關症狀群的可行性。 / 研究方法:本研究分為兩個部分。第一部分採用橫斷面的研究方法(n = 130),目的是為了找出最嚴重的症狀群,包括檢驗一個量表的信效度。第二部分包括健康教育干預專案的設計和預實驗。首先,研究者做了一個系統評價來評估心理及健康教育干預對管理癌症病人症狀群的效果。然後,研究者又做了一個質性研究,通過與25名鼻咽癌放療病人和16名醫護人員面對面訪談來瞭解目前營養相關症狀群的管理現狀,以便為干預的設計提供進一步線索。最後,研究者做了一個隨機對照試驗的預實驗(n = 40),來評價本研究所設計的健康教育干預專案的可行性。研究指標包括營養相關症狀群的嚴重性、體重、功能水準以及生活品質,並於干預前、放療第3周以及放療結束進行測量。統計推斷方法包括獨立樣本t檢驗、卡方檢驗、Fisher確切概率法和廣義估計方程模型,用以比較組間差異。 / 研究結果:第一部分的研究結果表明,中文版的M. D. Anderson症狀調查表(頭頸)的信效度良好。此外,四個症狀群被發現,其中以營養相關症狀群最為嚴重,因此被選為本研究的干預目標。第二部分,通過系統評價,研究者發現心理及健康教育干預,尤其是健康教育對管理癌症病人的症狀群有一定效果。接著,質性研究的結果進一步提示了健康教育干預項目的必要性,並為該專案的設計提供了具體方案。最後,預實驗表明本研究所設計的健康教育干預專案是可行的並受病人歡迎。該項目在減輕營養相關症狀群(Cohen’s d = -0.37)以及提高與身體(Cohen’s d = -0.15)和頭頸癌相關(Cohen’s d = -0.05)的生活品質上有一定效果。 / 研究結論:本研究所設計的健康教育干預專案是可行的,並對管理鼻咽癌病人放療期間的營養相關症狀群有一定效果。將來需要做一個大規模的研究來驗證該項目的有效性。" / Xiao, Wenli. / Thesis Ph.D. Chinese University of Hong Kong 2016. / Includes bibliographical references (leaves 226-250). / Abstracts also in Chinese. / Title from PDF title page (viewed on 01, February, 2018). / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only.
567

Clinical application of intensity and energy modulated radiotherapy with photon and electron beams

Mu, Xiangkui January 2005 (has links)
In modern, advanced radiotherapy (e.g. intensity modulated photon radiotherapy, IMXT) the delivery time for each fraction becomes prolonged to 10-20 minutes compared with the conventional, commonly 2-5 minutes. The biological effect of this prolongation is not fully known. The large number of beam directions in IMXT commonly leads to a large integral dose in the patient. Electrons would reduce the integral dose but are not suitable for treating deep-seated tumour, due to their limited penetration in tissues. By combining electron and photon beams, the dose distributions may be improved compared with either used alone. One obstacle for using electron beams in clinical routine is that there is no available treatment planning systems that optimise electron beam treatments in a similar way as for IMXT. Protons have an even more pronounced dose fall-off, larger penetration depth and less penumbra widening than electrons and are therefore more suitable for advanced radiotherapy. However, proton facilities optimised for advanced radiotherapy are not commonly available. In some instances electron beams may be an acceptable surrogate. The first part of this study is an experimental in vitro study where the situation in a tumour during fractionated radiotherapy is simulated. The effect of the prolonged fraction time is compared with the predictions by radiobiological models. The second part is a treatment planning study to analyse the mixing of electron and photon beams for at complex target volume in comparison with IMXT. In the next step a research version of an electron beam optimiser was used for the improvement of treatment plans. The aim was to develop a method for translating crude energy and intensity matrices for optimised electrons into a deliverable treatment plan without destroying the dose distribution. In the final part, different methods of treating the spinal canal in medulloblastoma were explored in a treatment planning study that was evaluated with biological models for estimating risks for late radiation effects. The effect on cell survival of prolonging fraction time at conventional doses/fraction is significant in an in vitro system. This effect is underestimated by biological models. Prolonging the fraction time will spare tissues with a fast DNA repair. Thus, there is a risk for sparing tumours. The mixed electron and photon beam technique has the potential to treat deep-seated tumours. Compared with IMXT the number of beams can be reduced and as a consequence, the time for each fraction could be kept shorter. The integral dose in the patient will also be lower. The mixed beam technique could potentially be further improved if automatic optimisation for electrons was available. The results suggest that optimisation and segmentation can be automated, and a deliverable treatment plan can be obtained with simple procedures without destroying the quality of the dose distribution. The integral dose in patients may lead to late radiation side effects. In childhood cancers the risk for development of radiation induced cancers is a reality and the integral dose outside the target volume should be minimised. Based on models for cancer induction, protons show the lowest risk while electrons have some benefit compared with different photon techniques. All methods are able to similarly well treat the target volume.
568

Exact minimisation of treatment time for the delivery of intensity modulated radiation therapy

Wake, Giulia M. G. H. January 2009 (has links)
This thesis investigates the exact minimisation of treatment delivery time for Intensity Modulated Radiation Therapy (IMRT) for the treatment of cancer using Multileaf Collimators (MLC). Although patients are required to remain stationary during the delivery of IMRT, inevitably some patient movement will occur, particularly if treatment times are longer than necessary. Therefore minimising the treatment delivery time of IMRT may result in less patient movement, less inaccuracy in the dosage received and a potentially improved outcome for the patient. When IMRT is delivered using multileaf collimators in 'step and shoot' mode, it consists of a sequence of multileaf collimator configurations, or shape matrices; for each, time is needed to set up the configuration, and in addition the patient is exposed to radiation for a specified time, or beam-on time. The 'step and shoot leaf sequencing' problems for minimising treatment time considered in this thesis are the constant set-up time Total Treatment Time (TTT) problem and the Beam-on Time Constrained Minimum Cardinality (BTCMC) problem. The TTT problem minimises a weighted sum of total beam-on time and total number of shape matrices used, whereas the BTCMC problem lexicographically minimises the total beam-on time then the number of shape matrices used in a solution. The vast majority of approaches to these strongly NP-hard problems are heuristics; of the few exact approaches, the formulations either have excessive computation times or their solution methods do not easily incorporate multileaf collimator mechanical constraints (which are present in most currently used MLC systems). In this thesis, new exact mixed integer and integer programming formulations for solving the TTT and BTCMC problems are developed. The models and solution methods considered can be applied to the unconstrained and constrained versions of the problems, where 'constrained' refers to the modelling of additional MLC mechanical constraints. Within the context of integer programming formulations, new and existing methods for improving the computational efficiency of the models presented are investigated. Numerical results for all variations considered are provided. This thesis demonstrates that significant computational improvement can be achieved for the exact mixed integer and integer programming models investigated, via solution approaches based on an idea of systematically 'stepping-up' through the number of shape matrices used in a formulation, via additional constraints (particularly symmetry breaking constraints) and via the application of improved bounds on variables. This thesis also makes a contribution to the wider field of integer programming through the examination of an interesting substructure of an exact integer programming model. In summary, this thesis presents a thorough analysis of possible integer programming models for the strongly NP-hard 'step and shoot' leaf sequencing problems and investigates and applies methods for improving the computational efficiency of such formulations. In this way, this thesis contributes to the field of leaf sequencing for the application of Intensity Modulated Radiation Therapy using Multileaf Collimators.
569

Metodologia para avaliação dos benefícios clínicos e socioeconômicos do uso da técnica de IMRT em tumores da próstata

Nunes, Isabella Paziam Fernandes. January 2018 (has links)
Orientador: Marco Antônio Rodrigues Fernandes / Resumo: O presente estudo consiste na análise da viabilidade econômica e financeira da implantação da radioterapia de intensidade modulada (IMRT) no tratamento do câncer de próstata e comparar seus benefícios clínicos frente aos procedimentos similares custeados pelos sistemas de saúde públicos e privados. Para tanto, foram analisadas as distribuições de dose de radiação preconizadas nos planejamentos radioterápicos com as técnicas de radioterapia conformacional tridimensional (3D-CRT) e de intensidade modulada (IMRT), prescrita para 20 pacientes com câncer de próstata tratados em um serviço de radioterapia privado. Para verificação da qualidade da distribuição de dose de radiação no volume de tratamento, foram analisados os índices de homogeneidade (IH) e de conformidade (IC) de cada um dos planos radioterápicos estudados. Em comparação com a técnica 3D-CRT, a técnica de IMRT permitiu uma melhor cobertura e conformação da dose prescrita no volume alvo de planejamento (PTV), porém distribuída de forma mais heterogênea. Além disso, avaliou-se os custos financeiros para aquisição dos equipamentos de irradiação e manutenção dos tratamentos, bem como os valores de repasses feitos pelos sistemas de saúde para os procedimentos de radioterapia em próstata. / Mestre
570

Metodologia para avaliação dos benefícios clínicos e socioeconômicos do uso da técnica de IMRT em tumores da próstata / Methodology for the evaluation of the clinical and socioeconomic benefits of IMRT technique in prostate tumors

Nunes, Isabella Paziam Fernandes [UNESP] 23 February 2018 (has links)
Submitted by ISABELLA PAZIAM FERNANDES NUNES null (ipaziam@me.com) on 2018-03-14T12:47:35Z No. of bitstreams: 1 dissertacao - nunes ipf.pdf: 3167962 bytes, checksum: bd9df494a7b84197900f4be8d90cd090 (MD5) / Approved for entry into archive by Luciana Pizzani null (luciana@btu.unesp.br) on 2018-03-19T11:47:25Z (GMT) No. of bitstreams: 1 nunes_ipf_me_bot.pdf: 3167962 bytes, checksum: bd9df494a7b84197900f4be8d90cd090 (MD5) / Made available in DSpace on 2018-03-19T11:47:25Z (GMT). No. of bitstreams: 1 nunes_ipf_me_bot.pdf: 3167962 bytes, checksum: bd9df494a7b84197900f4be8d90cd090 (MD5) Previous issue date: 2018-02-23 / O presente estudo consiste na análise da viabilidade econômica e financeira da implantação da radioterapia de intensidade modulada (IMRT) no tratamento do câncer de próstata e comparar seus benefícios clínicos frente aos procedimentos similares custeados pelos sistemas de saúde públicos e privados. Para tanto, foram analisadas as distribuições de dose de radiação preconizadas nos planejamentos radioterápicos com as técnicas de radioterapia conformacional tridimensional (3D-CRT) e de intensidade modulada (IMRT), prescrita para 20 pacientes com câncer de próstata tratados em um serviço de radioterapia privado. Para verificação da qualidade da distribuição de dose de radiação no volume de tratamento, foram analisados os índices de homogeneidade (IH) e de conformidade (IC) de cada um dos planos radioterápicos estudados. Em comparação com a técnica 3D-CRT, a técnica de IMRT permitiu uma melhor cobertura e conformação da dose prescrita no volume alvo de planejamento (PTV), porém distribuída de forma mais heterogênea. Além disso, avaliou-se os custos financeiros para aquisição dos equipamentos de irradiação e manutenção dos tratamentos, bem como os valores de repasses feitos pelos sistemas de saúde para os procedimentos de radioterapia em próstata. / The present study consists in analyzing the economic and financial viability to establish the intensity modulated radiotherapy (IMRT) in the treatment for prostate cancer and compare its clinical benefits to similar procedures funded by public and private health systems. In order to do so, the radiation absorbed-dose distributions recommended in the radiotherapy plans with three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT) techniques, prescribed for 20 patients with prostate cancer treated in a private radiotherapy clinic, were evaluated. To verify the quality of the radiation dose distribution in the treatment volume, the homogeneity index (HI) and the conformity index (CI) of each radiotherapy plans studied were analyzed. In contrast to the 3D-CRT technique, the IMRT technique allowed a better coverage and conformation of the radiation dose prescribed in the planning target volume (PTV), but distributed in a more heterogeneous way. It was also evaluated the financial costs for the acquisition of the irradiation equipment and for the maintenance of the treatments, as well as the values of the on-lending made by the health systems for the radiotherapy procedures for the prostate.

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