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1.
Radiat Environ Biophys ; 63(1): 47-57, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38194100

RESUMO

To compare treatment planning and dosimetric outcomes for hippocampal sparing whole brain radiotherapy (WBRT) with the simultaneous integrated boost (SIB) in brain metastasis (BM) patients using tumour control probability (TCP) and normal tissue complication probability (NTCP) formalism between IMRT, VMAT, and HT techniques. In this retrospective study, the treatment data of 20 BM patients who typically received whole brain radiation with SIB treatment were used. Prescription doses of 30 Gy and 36 Gy was delivered in 10 fractions for WBRT and SIB, respectively. Niemierko and LKB models were applied for calculating TCP and NTCP. All the plans were evaluated for the RTOG 0933 protocol criteria and found acceptable. Additionally, the homogeneity of the PTV boost is 0.07 ± 0.01, 0.1 ± 0.04, and 0.08 ± 0.02 for IMRT, VMAT, and HT, respectively (P < 0.05). The percentage of TCP for the PTV boost was 99.99 ± 0.003, 99.98 ± 0.004, and 99.99 ± 0.002 of IMRT, VMAT, and HT, respectively, (P < 0.005). The NTCP value of the lenses was higher with the VMAT plan as compared to IMRT and HT Plans. The hippocampal NTCP values are equal in all three planning proficiencies. The techniques like IMRT, VMAT, and HT can reduce the dose received by hippocampus to the dosimetric threshold during the delivery of WBRT with hippocampal sparing and can simultaneously boost multiple metastases. Overall, the high-quality dose distribution, TCP, and NTCP comparison between all three planning techniques show that the HT technique has better results when compared to the VMAT and IMRT techniques.


Assuntos
Neoplasias Encefálicas , Radioterapia de Intensidade Modulada , Humanos , Estudos Retrospectivos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundário , Encéfalo , Hipocampo , Órgãos em Risco
2.
Asian Pac J Cancer Prev ; 23(12): 4233-4241, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36580006

RESUMO

OBJECTIVE: The present investigation intends to identify the optimal radiotherapy treatment plan for synchronous bilateral breast cancer (SBBC) using dosimetric and radiobiological indexes for three techniques, namely, helical tomotherapy (HT), volumetric modulated arc therapy (VMAT), and intensity-modulated radiotherapy (IMRT). METHODS: Twenty SBBC treated female patients treatment planning data (average age of 52.5 years) were used as the sample for the present study. Three different plans were created using 50 Gy in a 25 fraction dose regime. Poisson, Niemierko, and LKB models were applied for calculating normal tissue complication probability (NTCP) and tumour control probability (TCP). RESULT: The target average dose comparison between IMRT with HT and VMAT with HT was highly substantial (P=0.001). The percentage of TCP for IMRT, VMAT, and HT in the Poisson model were 93.70±0.28, 94.68±0.30, and 94.34±0.57, respectively (p<0.05). The dose maximum was lower for the whole lung in the HT plan, with an average dose of 49.31Gy±3.9 (p<0.009). The NTCP values of both Niemierko and LKB models were lower for the heart, lungs, and liver for the IMRT plan. CONCLUSION: The sparing of organs at risk was higher in the HT plan dosimetrically, and the TCP was higher in the three techniques. The comparison between the three techniques shows that the IMRT and HT techniques could be considered for treating SBBC.


Assuntos
Neoplasias da Mama , Radioterapia de Intensidade Modulada , Humanos , Feminino , Pessoa de Meia-Idade , Radioterapia de Intensidade Modulada/métodos , Neoplasias da Mama/radioterapia , Dosagem Radioterapêutica , Radiometria , Planejamento da Radioterapia Assistida por Computador/métodos , Órgãos em Risco
3.
Biomed Res Int ; 2022: 9900668, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35937383

RESUMO

Cancer of the mesothelium, sometimes referred to as malignant mesothelioma (MM), is an extremely uncommon form of the illness that almost always results in death. Chemotherapy, surgery, radiation therapy, and immunotherapy are all potential treatments for multiple myeloma; however, the majority of patients are identified with the disease at an advanced stage, at which time it is resistant to these therapies. After obtaining a diagnosis of advanced multiple myeloma, the average length of time that a person lives is one year after hearing this news. There is a substantial link between asbestos exposure and mesothelioma (MM). Using an approach that enables feature selection and machine learning, this article proposes a classification and detection method for mesothelioma cancer. The CFS correlation-based feature selection approach is first used in the feature selection process. It acts as a filter, selecting just the traits that are relevant to the categorization. The accuracy of the categorization model is improved as a direct consequence of this. After that, classification is carried out with the help of naive Bayes, fuzzy SVM, and the ID3 algorithm. Various metrics have been utilized during the process of measuring the effectiveness of machine learning strategies. It has been discovered that the choice of features has a substantial influence on the accuracy of the categorization.


Assuntos
Aprendizado de Máquina , Mesotelioma , Algoritmos , Teorema de Bayes , Humanos , Mesotelioma/classificação , Mesotelioma/diagnóstico , Mesotelioma Maligno/diagnóstico , Mieloma Múltiplo/diagnóstico
4.
J Med Phys ; 46(4): 244-252, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35261494

RESUMO

Purpose: The preferred radiotherapy treatment for medulloblastoma is craniospinal irradiation (CSI). With the aim of developing the potential to reduce normal tissue dose and associated post-treatment complications with photon and proton radiotherapy techniques for CSI. This report aims to carefully compare and rank treatment planning and dosimetric outcomes for pediatric medulloblastoma patients using normal tissue complication probability (NTCP) formalism between photon (three-dimensional conformal radiotherapy, intensity-modulated radiotherapy [IMRT], volumetric-modulated arc therapy [VMAT], and HT) and proton CSI. Methods and Materials: The treatment data of eight pediatric patients who typically received CSI treatment were used in this study. The patients were 7 years of age on average, with ages ranging from 3 to 11 years. A prescription dose of 3600 cGy was delivered in 20 fractions by the established planning methods. The Niemierko's and Lyman-Kutcher-Burman models were followed to carefully estimate NTCP and compare different treatment plans. Results: The NTCP of VMAT plans in upper and middle thoracic volumes was relatively high compared to helical tomotherapy (HT) and pencil beam scanning (PBS) (all P < 0.05). PBS rather than IMRT and VMAT in the middle thoracic region (P < 0.06) could significantly reduce the NTCP of the heart. PBS significantly reduced NTCP of the lungs and liver (all P < 0.05). Conclusion: The NTCP and tumor control probability (TCP) model-based plan ranking along with dosimetric indices will help the clinical practitioner or medical physicists to choose the best treatment plan for each patient based on their anatomical or clinical challenges.

5.
Indian J Med Res ; 144(1): 11-20, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27834321

RESUMO

Undernutrition and tuberculosis (TB) are linked and have a bidirectional relationship. Undernutrition increases the risk of TB which in turn, can lead to malnutrition. Undernutrition not only is a risk factor for progression of latent TB infection to active disease, but also increases the risk of drug toxicity, relapse and death once TB develops. The dietary intake of TB patients in the country is inadequate. Nutritional supplementation in patients with TB is associated with faster sputum conversion, higher cure and treatment completion rates, significant gain in body weight and body composition as well as better performance status. The Government of India has various social support schemes (including nutrition supplementation schemes) and policies, at the Centre as well as State levels. Here we discuss some successful examples and suggest a few solutions to address this gap; like considering TB patients as a vulnerable group for "Targeted Public Distribution System" and providing extra rations for the duration of treatment. Recommendations for the research community, civil societies, government organizations, non-governmental and corporate sector on the actions needed to achieve the goals of the End TB Strategy are also provided. Ultimately, reduction of TB burden in India and its elimination will require improving the nutritional status of the community as a whole.


Assuntos
Desnutrição/epidemiologia , Tuberculose/epidemiologia , Suplementos Nutricionais , Humanos , Índia , Desnutrição/complicações , Desnutrição/fisiopatologia , Estado Nutricional , Fatores de Risco , Tuberculose/complicações , Tuberculose/fisiopatologia
6.
East Asian Arch Psychiatry ; 24(1): 16-22, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24676483

RESUMO

OBJECTIVE: Parents' positive attitudes and psychological wellbeing play an important role in the development of the children with developmental disability. This study aimed to measure the prevalence of psychological problems among mothers of children with autism disorder, intellectual disability, and Down syndrome. The second aim was to assess the differences in mothers' attitudes and psychological problems among their children with intellectual disability, autism disorder, and Down syndrome. The third aim was to identify whether negative attitude was a predictor of psychological problems in these mothers. METHODS: In this study, 112 mothers of children having mild and moderate levels of autism disorder, Down syndrome, and intellectual disability were assessed using the Parental Attitude Scale and General Health Questionnaire-28. RESULTS: Overall, mothers of children with intellectual disability were found to have the most negative attitude towards their child. Mothers of children with autism disorder exhibited higher scores on somatic symptoms, anxiety, and social dysfunction when compared with their counterparts with Down syndrome and intellectual disability. Negative attitude was a significant predictor of psychological problems. CONCLUSION: Parental attitudes and psychological problems would vary among mothers of children with different types of developmental disability.


Assuntos
Atitude , Deficiências do Desenvolvimento/psicologia , Transtornos Mentais/epidemiologia , Mães/psicologia , Adulto , Transtorno Autístico/psicologia , Criança , Síndrome de Down/psicologia , Feminino , Humanos , Deficiência Intelectual/psicologia , Malásia/epidemiologia , Masculino , Transtornos Mentais/psicologia , Prevalência
7.
J Nanosci Nanotechnol ; 13(5): 3535-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23858896

RESUMO

Ferrites are extremely important magnetic ceramics in the production of electronic components because they reduce the energy losses by the induced currents acting as electrical insulators. Similarly, the spinel-structured cobalt-based ferrites are promising materials for stress, torsion sensors and energy storage applications (anode materials in lithium batteries, fuel cells and solar cells). Therefore, many studies have focused on cobalt ferrites obtained using conventional techniques. Different sintering conditions, types and levels of substitution result in different microstructures and magnetostriction coefficients under a wide range of preparation conditions. Despite many attempts, there are no specific reports on the trivalent substitution of yttrium in cobalt ferrite to the best of our knowledge. In the present study, yttrium-doped cobalt ferrite was prepared with different concentrations to identify the crystallite size with respect to the yttrium concentration, temperature and changes in the structural and electrical properties. In addition, the resistance of the nanostructured yttrium-doped cobalt ferrites nanopowders was analyzed. The resistance was increased by the addition of yttrium to cobalt ferrites.


Assuntos
Cobalto/química , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Ítrio/química , Impedância Elétrica , Temperatura Alta , Campos Magnéticos , Teste de Materiais , Tamanho da Partícula , Transição de Fase
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