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1.
Br J Radiol ; 93(1107): 20190807, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32003574

RESUMO

After years of lethargy, studies on two non-conventional microstructures in time and space of the beams used in radiation therapy are enjoying a huge revival. The first effect called "FLASH" is based on very high dose-rate irradiation (pulse amplitude ≥106 Gy/s), short beam-on times (≤100 ms) and large single doses (≥10 Gy) as experimental parameters established so far to give biological and potential clinical effects. The second effect relies on the use of arrays of minibeams (e.g., 0.5-1 mm, spaced 1-3.5 mm). Both approaches have been shown to protect healthy tissues as an endpoint that must be clearly specified and could be combined with each other (e.g., minibeams under FLASH conditions). FLASH depends on the presence of oxygen and could proceed from the chemistry of peroxyradicals and a reduced incidence on DNA and membrane damage. Minibeams action could be based on abscopal effects, cell signalling and/or migration of cells between "valleys and hills" present in the non-uniform irradiation field as well as faster repair of vascular damage. Both effects are expected to maintain intact the tumour control probability and might even preserve antitumoural immunological reactions. FLASH in vivo experiments involving Zebrafish, mice, pig and cats have been done with electron beams, while minibeams are an intermediate approach between X-GRID and synchrotron X-ray microbeams radiation. Both have an excellent rationale to converge and be applied with proton beams, combining focusing properties and high dose rates in the beam path of pencil beams, and the inherent advantage of a controlled limited range. A first treatment with electron FLASH (cutaneous lymphoma) has recently been achieved, but clinical trials have neither been presented for FLASH with protons, nor under the minibeam conditions. Better understanding of physical, chemical and biological mechanisms of both effects is essential to optimize the technical developments and devise clinical trials.


Assuntos
Tratamentos com Preservação do Órgão/métodos , Terapia com Prótons/métodos , Animais , Gatos , Proliferação de Células , Dano ao DNA , Reparo do DNA , Fracionamento da Dose de Radiação , Linfoma Cutâneo de Células T/radioterapia , Camundongos , Órgãos em Risco/efeitos da radiação , Oxigênio , Consumo de Oxigênio , Lesões por Radiação/prevenção & controle , Tolerância a Radiação , Radiometria/métodos , Neoplasias Cutâneas/radioterapia , Análise Espaço-Temporal , Suínos , Peixe-Zebra
10.
Br J Radiol ; 93(1107): 20190845, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31904261

RESUMO

OBJECTIVES: The purpose of this study is to investigate the dosimetric effect and clinical impact of delivering a focal radiotherapy boost dose to multiparametric MRI (mp-MRI)-defined dominant intraprostatic lesions (DILs) in prostate cancer using proton therapy. METHODS: We retrospectively investigated 36 patients with pre-treatment mp-MRI and CT images who were treated using pencil beam scanning (PBS) proton radiation therapy to the whole prostate. DILs were contoured on co-registered mp-MRIs. Simultaneous integrated boost (SIB) plans using intensity-modulated proton therapy (IMPT) were created based on conventional whole-prostate-irradiation for each patient and optimized with additional DIL coverage goals and urethral constraints. DIL dose coverage and organ-at-risk (OAR) sparing were compared between conventional and SIB plans. Tumor control probability (TCP) and normal tissue complication probability (NTCP) were estimated to evaluate the clinical impact of the SIB plans. RESULTS: Optimized SIB plans significantly escalated the dose to DILs while meeting OAR constraints. SIB plans were able to achieve 125, 150 and 175% of prescription dose coverage in 74, 54 and 17% of 36 patients, respectively. This was modeled to result in an increase in DIL TCP by 7.3-13.3% depending on α/ß and DIL risk level. CONCLUSION: The proposed mp-MRI-guided DIL boost using proton radiation therapy is feasible without violating OAR constraints and demonstrates a potential clinical benefit by improving DIL TCP. This retrospective study suggested the use of IMPT-based DIL SIB may represent a strategy to improve tumor control. ADVANCES IN KNOWLEDGE: This study investigated the planning of mp-MRI-guided DIL boost in prostate proton radiation therapy and estimated its clinical impact with respect to TCP and NTCP.


Assuntos
Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Terapia com Prótons/métodos , Reirradiação/métodos , Idoso , Idoso de 80 Anos ou mais , Fracionamento da Dose de Radiação , Humanos , Masculino , Pessoa de Meia-Idade , Tratamentos com Preservação do Órgão/métodos , Órgãos em Risco/diagnóstico por imagem , Órgãos em Risco/efeitos da radiação , Próstata/diagnóstico por imagem , Próstata/efeitos da radiação , Neoplasias da Próstata/patologia , Lesões por Radiação/prevenção & controle , Dosagem Radioterapêutica , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Uretra/diagnóstico por imagem
11.
Br J Radiol ; 93(1107): 20190955, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31971818

RESUMO

Patients with squamous cell carcinoma of the oropharynx are generally treated with (chemo) radiation. Patients with oropharyngeal cancer have better survival than patients with squamous cell carcinoma of other head and neck subsites, especially when related to human papillomavirus. However, radiotherapy results in a substantial percentage of survivors suffering from significant treatment-related side-effects. Late radiation-induced side-effects are mostly irreversible and may even be progressive, and particularly xerostomia and dysphagia affect health-related quality of life. As the risk of radiation-induced side-effects highly depends on dose to healthy normal tissues, prevention of radiation-induced xerostomia and dysphagia and subsequent improvement of health-relatedquality of life can be obtained by applying proton therapy, which offers the opportunity to reduce the dose to both the salivary glands and anatomic structures involved in swallowing.This review describes the results of the first cohort studies demonstrating that proton therapy results in lower dose levels in multiple organs at risk, which translates into reduced acute toxicity (i.e. up to 3 months after radiotherapy), while preserving tumour control. Next to reducing mucositis, tube feeding, xerostomia and distortion of the sense of taste, protons can improve general well-being by decreasing fatigue and nausea. Proton therapy results in decreased rates of tube feeding dependency and severe weight loss up to 1 year after radiotherapy, and may decrease the risk of radionecrosis of the mandible. Also, the model-based approach for selecting patients for proton therapy in the Netherlands is described in this review and future perspectives are discussed.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Transtornos de Deglutição/prevenção & controle , Neoplasias Orofaríngeas/radioterapia , Terapia com Prótons/métodos , Lesões por Radiação/prevenção & controle , Xerostomia/prevenção & controle , Idoso , Transtornos de Deglutição/etiologia , Nutrição Enteral/estatística & dados numéricos , Humanos , Mandíbula/efeitos da radiação , Pessoa de Meia-Idade , Países Baixos , Órgãos em Risco/efeitos da radiação , Qualidade de Vida , Glândulas Salivares/efeitos da radiação , Xerostomia/etiologia
12.
Br J Radiol ; 93(1108): 20190792, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31939310

RESUMO

OBJECTIVES: To evaluate the feasibility and optimal restricted angle of the complete-directional-complete block (CDCB) technique in helical tomotherapy (HT) by including regional nodal irradiation (RNI) with the internal mammary node (IMN) in left-sided breast cancer. METHODS: Ten left-sided breast cancer patients treated with 50 Gy in 25 fractions were compared with five-field intensity-modulated radiation therapy (5F-IMRT) and six types of HT plans. In the HT plans, complete block (CB), organ-based directional block (OBDB) and CDCB with different restricted angles were used. RESULTS: The conformity index (CI) between the CDCB0,10,15,20 and 5F-IMRT groups was similar. Compared to CB, OBDB and 5F-IMRT, CDCB20 resulted in a decreased ipsilateral mean lung dose. The low-dose region (V5) of the ipsilateral lung in OBDB (84.0%) was the highest among all techniques (p < 0.001). The mean dose of the heart in CB was significantly reduced (by 11.5-22.4%) compared with other techniques. The V30 of the heart in CDCB20 (1.9%) was significantly lower than that of CB, OBDB and 5F-IMRT. Compared to the mean dose of the left anterior descending (LAD) artery of 5F-IMRT (27.0 Gy), CDCB0, CDCB10, CDCB15, CDCB20 and OBDB reduced the mean dose effectively by 31.7%, 38.3%, 39.6%, 42.0 and 56.2%, respectively. Considering the parameters of the organs-at-risk (OARs), CDCB10,15,20 had higher expectative values than the other techniques (p = 0.01). CONCLUSIONS: HT with the CDCB technique is feasible for treating left-sided breast cancer patients. The CDCB10-20 techniques not only achieved similar planning target volume coverage, homogeneity and dose conformity but also allowed better sparing of the heart and bilateral lungs. ADVANCES IN KNOWLEDGE: For left-sided breast cancer patients whose RNI field includes the IMN, heart avoidance is an important issue. The CDCB technique achieved good PTV coverage, homogeneity and dose conformity and allowed better sparing of the mean dose of the lung, the LAD artery, and the heart and reduced the V30 of the heart.


Assuntos
Coração/efeitos da radiação , Pulmão/efeitos da radiação , Irradiação Linfática/métodos , Órgãos em Risco/efeitos da radiação , Lesões por Radiação/prevenção & controle , Radioterapia de Intensidade Modulada/métodos , Neoplasias Unilaterais da Mama/radioterapia , Fracionamento da Dose de Radiação , Estudos de Viabilidade , Feminino , Humanos , Órgãos em Risco/diagnóstico por imagem , Planejamento da Radioterapia Assistida por Computador/métodos , Neoplasias Unilaterais da Mama/diagnóstico por imagem
13.
Br J Radiol ; 93(1107): 20190787, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31794249

RESUMO

Owing to the favorable physical and biological properties of swift ions in matter, their application to radiation therapy for highly selective cancer treatment is rapidly spreading worldwide. To date, over 90 ion therapy facilities are operational, predominantly with proton beams, and about the same amount is under construction or planning.Over the last decades, considerable developments have been achieved in accelerator technology, beam delivery and medical physics to enhance conformation of the dose delivery to complex shaped tumor volumes, with excellent sparing of surrounding normal tissue and critical organs. Nevertheless, full clinical exploitation of the ion beam advantages is still challenged, especially by uncertainties in the knowledge of the beam range in the actual patient anatomy during the fractionated course of treatment, thus calling for continued multidisciplinary research in this rapidly emerging field.This contribution will review latest developments aiming to image the patient with the same beam quality as for therapy prior to treatment, and to visualize in-vivo the treatment delivery by exploiting irradiation-induced physical emissions, with different level of maturity from proof-of-concept studies in phantoms and first in-silico studies up to clinical testing and initial clinical evaluation.


Assuntos
Neoplasias/diagnóstico por imagem , Neoplasias/radioterapia , Terapia com Prótons/tendências , Absorção de Radiação , Institutos de Câncer/estatística & dados numéricos , Institutos de Câncer/tendências , Humanos , Órgãos em Risco/efeitos da radiação , Tomografia por Emissão de Pósitrons , Terapia com Prótons/métodos , Terapia com Prótons/estatística & dados numéricos , Lesões por Radiação/prevenção & controle , Radioterapia Guiada por Imagem , Incerteza
14.
Br J Radiol ; 93(1107): 20190573, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31778315

RESUMO

OBJECTIVE: Classical robust optimization (cRO) in intensity-modulated proton therapy (IMPT) considers isocenter position and particle range uncertainties; anatomical robust optimization (aRO) aims to consider additional non-rigid positioning variations. This work compares the influence of different uncertainty sources on the robustness of cRO and aRO IMPT plans for head and neck squamous cell carcinoma (HNSCC). METHODS: Two IMPT plans were optimized for 20 HNSCC patients who received weekly control CTs (cCT): cRO, using solely the planning CT, and aRO, including 2 additional cCTs. The robustness of the plans in terms of clinical target volume (CTV) coverage and organ at risk (OAR) sparing was analyzed considering stepwise the influence of (1) non-rigid anatomical variations given by the weekly cCT, (2) with fraction-wise added rigid random setup errors and (3) additional systematic proton range uncertainties. RESULTS: cRO plans presented significantly higher nominal CTV coverage but are outperformed by aRO plans when considering non-rigid anatomical variations only, as cRO and aRO plans presented a median target coverage (D98%) decrease for the low-risk/high-risk CTV of 1.8/1.1 percentage points (pp) and -0.2 pp/-0.3 pp, respectively. Setup and range uncertainties had larger influence on cRO CTV coverage, but led to similar OAR dose changes in both plans. Considering all error sources, 10/2 cRO/aRO patients missed the CTV coverage and a limited number exceeded some OAR constraints in both plans. CONCLUSION: Non-rigid anatomical variations are mainly responsible for critical target coverage loss of cRO plans, whereas the aRO approach was robust against such variations. Both plans provide similar robustness of OAR parameters. ADVANCES IN KNOWLEDGE: The influence of different uncertainty sources was quantified for robust IMPT HNSCC plans.


Assuntos
Neoplasias de Cabeça e Pescoço/radioterapia , Terapia com Prótons/métodos , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada/métodos , Carcinoma de Células Escamosas de Cabeça e Pescoço/radioterapia , Incerteza , Humanos , Órgãos em Risco/efeitos da radiação , Posicionamento do Paciente , Lesões por Radiação/prevenção & controle , Erros de Configuração em Radioterapia , Radioterapia de Intensidade Modulada/normas , Estudos Retrospectivos
15.
Int J Radiat Oncol Biol Phys ; 106(3): 621-629, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31759074

RESUMO

PURPOSE: Preclinical research into ultrahigh dose rate (eg, ≥40 Gy/s) "FLASH"-radiation therapy suggests a decrease in side effects compared with conventional irradiation while maintaining tumor control. When FLASH is delivered using a scanning proton beam, tissue becomes subject to a spatially dependent range of dose rates. This study systematically investigates dose rate distributions and delivery times for proton FLASH plans using stereotactic lung irradiation as the paradigm. METHODS AND MATERIALS: Stereotactic lung radiation therapy FLASH-plans, using 244 MeV scanning proton transmission beams, with the Bragg peak behind the body, were made for 7 patients. Evaluated parameters were dose rate distribution within a beam, overall irradiation time, number of times tissue is irradiated, and quality of the FLASH-plans compared with the clinical volumetric-modulated arc therapy (VMAT) plans. RESULTS: Sparing of lungs, thoracic wall, and heart in the FLASH-plans was equal to or better than that in the VMAT-plans. For a spot peak dose rate (SPDR, the dose rate in the middle of the spot) of 100 Gy/s, ∼40% of dose is delivered at FLASH dose rates, and for SPDR = 360 Gy/s this increased to ∼75%. One-hundred percent FLASH dose rate cannot be achieved owing to small contributions from distant spots with lower dose rates. The total irradiation time varied between 300 to 730 ms, and around 85% of the dose-receiving body volume was irradiated by either 1 or 2 beams. CONCLUSIONS: Clinical implementation of FLASH using scanning proton beams requires multiple treatment planning considerations: dosimetric, temporal, and spatial parameters all seem important. The FLASH efficiency of a scanning proton beam increases with SPDR. The methodology proposed in this proof-of-principle study provides a framework for evaluating the FLASH characteristics of scanning proton beam plans and can be adapted as FLASH parameters are better defined. It currently seems logical to optimize plans for the shortest delivery time, maximum amount of high dose rate coverage, and maximum amount of single beam and continuous irradiation.


Assuntos
Neoplasias Pulmonares/radioterapia , Terapia com Prótons/métodos , Radiocirurgia/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Coração , Humanos , Pulmão , Tratamentos com Preservação do Órgão/métodos , Órgãos em Risco , Estudo de Prova de Conceito , Terapia com Prótons/efeitos adversos , Lesões por Radiação/prevenção & controle , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos , Medula Espinal , Parede Torácica , Fatores de Tempo
16.
Br J Radiol ; 93(1107): 20190378, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31430188

RESUMO

Radiation therapy is an essential component of treatment for locally advanced non-small cell lung cancer (NSCLC) but can be technically challenging because of the proximity of lung tumors to nearby critical organs or structures. The most effective strategy for reducing radiation-induced toxicity is to reduce unnecessary exposure of normal tissues by using advanced technology; examples from photon (X-ray) therapy have included three-dimensional conformal radiation therapy versus its predecessor, two-dimensional radiation therapy, and intensity-modulated photon radiation therapy versus its predecessor, three-dimensional conformal therapy. Using particle-beam therapy rather than photons offers the potential for further advantages because of the unique depth-dose characteristics of the particles, which can be exploited to allow still higher dose escalation to tumors with greater sparing of normal tissues, with the ultimate goal of improving local tumor control and survival while preserving quality of life by reducing treatment-related toxicity. However, the costs associated with particle therapy with protons are considerably higher than the current state of the art in photon technology, and evidence of clinical benefit from protons is increasingly being demanded to justify the higher financial burden on the healthcare system. Some such evidence is available from preclinical studies, from retrospective, single-institution clinical series, from analyses of national databases, and from single-arm prospective studies in addition to several ongoing randomized comparative trials. This review summarizes the rationale for and challenges of using proton therapy to treat thoracic cancers, reviews the current clinical experience, and suggests topics for future research.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Órgãos em Risco/efeitos da radiação , Terapia com Prótons/métodos , Lesões por Radiação/prevenção & controle , Radioterapia de Intensidade Modulada/métodos , Carcinoma Pulmonar de Células não Pequenas/patologia , Previsões , Humanos , Neoplasias Pulmonares/patologia , Tratamentos com Preservação do Órgão/métodos , Estudos Prospectivos , Terapia com Prótons/economia , Terapia com Prótons/tendências , Qualidade de Vida , Radioterapia Conformacional/métodos , Radioterapia de Intensidade Modulada/economia , Radioterapia de Intensidade Modulada/tendências , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Resultado do Tratamento
17.
Int J Radiat Oncol Biol Phys ; 106(1): 194-205, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31610250

RESUMO

PURPOSE: To develop and validate combined ion-beam with constant relative biological effectiveness (RBE) (CICR) particle therapy in single field arrangements for improved treatment efficacy, robustness, and normal tissue sparing. METHODS AND MATERIALS: The PRECISE (PaRticle thErapy using single and Combined Ion optimization StratEgies) treatment planning system was developed to investigate clinical viability of CICR treatments. Single-field uniform dose (SFUD) with a single ion (proton [p], helium [He], or carbon [C]) and CICR (C-p and C-He) treatments were generated for 3 patient cases with a clinically prescribed dose of 3 Gy (RBE) per fraction. Spread-out Bragg peak plans were irradiated in homogenous and clinical-like settings using an anthropomorphic head phantom. A dosimetric and biological verification of CICRC-p treatments using a murine glioma cell line (GL261) was performed. RESULTS: CICR treatment plans for the 3 patients presented highly uniform physical dose while reducing high dose-averaged linear energy transfer gradients compared with carbon ions alone. When considering uncertainty in tissue parameter (α/ß)x assignment and RBE modeling, the CICRC-p treatment exhibited enhanced biophysical stability within the target volume, similar to protons alone. CICR treatments reduced dose to normal tissue surrounding the target, exhibiting similar or improved dosimetric features compared with SFUDHe. For both CICRC-p and SFUD treatments, measurements verified the planned dose in the target within ∼3%. Planned versus measured target RBE values were 1.38 ± 0.02 and 1.39 ± 0.07 (<1% deviation), respectively, for the CICRC-p treatment in heterogenous settings. CONCLUSIONS: Here, we demonstrate that by combining 2 (or more) ions in a single field arrangement, more robust biological and more conformal dose distributions can be delivered compared with conventional particle therapy treatment planning. This work constitutes the first dosimetric and biological verification of multi-ion particle therapy in homogeneous as well as heterogenous settings.


Assuntos
Neoplasias Encefálicas/radioterapia , Carcinoma Adenoide Cístico/radioterapia , Cordoma/radioterapia , Glioma/radioterapia , Radioterapia com Íons Pesados/métodos , Tratamentos com Preservação do Órgão/métodos , Neoplasias da Coluna Vertebral/radioterapia , Animais , Neoplasias Encefálicas/diagnóstico por imagem , Carbono/uso terapêutico , Carcinoma Adenoide Cístico/diagnóstico por imagem , Linhagem Celular Tumoral , Cordoma/diagnóstico por imagem , Terapia Combinada/métodos , Fracionamento da Dose de Radiação , Glioma/diagnóstico por imagem , Hélio/uso terapêutico , Humanos , Transferência Linear de Energia , Camundongos , Órgãos em Risco , Imagens de Fantasmas , Terapia com Prótons/métodos , Lesões por Radiação/prevenção & controle , Planejamento da Radioterapia Assistida por Computador , Eficiência Biológica Relativa , Sacro , Neoplasias da Coluna Vertebral/diagnóstico por imagem
18.
Br J Radiol ; 93(1107): 20190578, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31868523

RESUMO

OBJECTIVES: Proton minibeam radiation therapy (pMBRT) is a novel therapeutic strategy that combines the benefits of proton therapy with the remarkable normal tissue preservation observed with the use of submillimetric spatially fractionated beams. This promising technique has been implemented at the Institut Curie-Proton therapy centre (ICPO) using a first prototype of a multislit collimator. The purpose of this work was to develop a Monte Carlo-based dose calculation engine to reliably guide preclinical studies at ICPO. METHODS: The whole "Y1"-passive beamline at the ICPO, including pMBRT implementation, was modelled using the Monte Carlo GATE v. 7.0 code. A clinically relevant proton energy (100 MeV) was used as starting point. Minibeam generation by means of the brass collimator used in the first experiments was modelled. A virtual source was modelled at the exit of the beamline nozzle and outcomes were compared with dosimetric measurements performed with EBT3 gafchromic films and a diamond detector in water. Dose distributions were recorded in a water phantom and in rat CT images (7-week-old male Fischer rats). RESULTS: The dose calculation engine was benchmarked against experimental data and was then used to assess dose distributions in CT images of a rat, resulting from different irradiation configurations used in several experiments. It reduced computational time by an order of magnitude. This allows us to speed up simulations for in vivo trials, where we obtained peak-to-valley dose ratios of 1.20 ± 0.05 and 6.1 ± 0.2 for proton minibeam irradiations targeting the tumour and crossing the rat head. Tumour eradication was observed in the 67 and 22% of the animals treated respectively. CONCLUSION: A Monte Carlo dose calculation engine for pMBRT implementation with mechanical collimation has been developed. This tool can be used to guide and interpret the results of in vivo trials. ADVANCES IN KNOWLEDGE: This is the first Monte Carlo dose engine for pMBRT that is being used to guide preclinical trials in a clinical proton therapy centre.


Assuntos
Dosimetria Fotográfica/métodos , Método de Monte Carlo , Terapia com Prótons/métodos , Animais , Benchmarking , Masculino , Órgãos em Risco , Imagens de Fantasmas , Terapia com Prótons/instrumentação , Hipofracionamento da Dose de Radiação , Lesões por Radiação/prevenção & controle , Dosagem Radioterapêutica , Ratos , Ratos Endogâmicos F344 , Espalhamento de Radiação
19.
Int. j. morphol ; 37(4): 1564-1571, Dec. 2019. tab
Artigo em Espanhol | LILACS | ID: biblio-1040170

RESUMO

Las glándulas salivales humanas pueden ser gravemente lesionadas por la radioterapia utilizada contra neoplasias de cabeza y cuello, produciendo hiposialia y xerostomía, las cuales afectan la salud oral y sistémica, mermando la calidad de vida de la persona. Los tratamientos convencionales actuales están diseñados para disminuir los síntomas, sin actuar sobre los cambios fisiopatológicos que se dan a nivel glandular. Esta revisión intenta analizar aquellas terapias preventivas y/o curativas que están desarrollándose en el campo biomolecular y que tienen un futuro prometedor por sus características innovadoras: terapia génica, terapia con células madre y terapia con factores de crecimiento. Se evidencia un aporte adicional de la nanotecnología, la cual está mejorando las vías de aplicación de los tratamientos.


Human salivary glands can be seriously injured by the radiotherapy used against head and neck neoplasms, producing hyposialia and xerostomy, which affect oral and systemic health, diminishing the person's quality of life. Current conventional treatments are designed to reduce symptoms, without acting on the pathophysiological changes that occur at the glandular level. This review attempts to analyze those preventive and /or curative therapies that are developing in the biomolecular field and that have a promising future due to their innovative features: Gene therapy, stem cell therapy and growth factor therapy. An additional contribution of nanotechnology is evident, which is improving the routes of treatment application.


Assuntos
Humanos , Radioterapia/efeitos adversos , Doenças das Glândulas Salivares/prevenção & controle , Células-Tronco/fisiologia , Terapia Genética/métodos , Peptídeos e Proteínas de Sinalização Intercelular/uso terapêutico , Lesões por Radiação/prevenção & controle , Protetores contra Radiação/uso terapêutico , Doenças das Glândulas Salivares/terapia , Glândulas Salivares/efeitos da radiação , Xerostomia/prevenção & controle , Nanotecnologia
20.
Tex Heart Inst J ; 46(3): 167-171, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31708696

RESUMO

Exposure to ionizing radiation during cardiac catheterization can have harmful consequences for patients and for the medical staff involved in the procedures. Minimizing radiation doses during the procedures is essential. We investigated whether fine-tuning the radiation protocol reduces radiation doses in the cardiac catheterization laboratory. In January 2016, we implemented a new protocol with reduced radiation doses in the Hospital de Jerez catheterization laboratory. We analyzed 170 consecutive coronary interventional procedures (85 of which were performed after the new protocol was implemented) and the personal dosimeters of the interventional cardiologists who performed the procedures. Overall, the low-radiation protocol reduced air kerma (dose of radiation) by 44.9% (95% CI, 18.4%-70.8%; P=0.001). The dose-area product decreased by 61% (95% CI, 30.2%-90.1%; P <0.001) during percutaneous coronary interventions. We also found that the annual deep (79%, P=0.026) and shallow (62.2%, P=0.035) radiation doses to which primary operators were exposed decreased significantly under the low-radiation protocol. These dose reductions were achieved without increasing the volume of contrast media, fluoroscopy time, or rates of procedural complications, and without reducing the productivity of the laboratory. Optimizing the radiation safety protocol effectively reduced radiation exposure in patients and operators during cardiac catheterization procedures.


Assuntos
Cateterismo Cardíaco/métodos , Angiografia Coronária/efeitos adversos , Fluoroscopia/efeitos adversos , Exposição Ocupacional/efeitos adversos , Exposição à Radiação/efeitos adversos , Lesões por Radiação/prevenção & controle , Medição de Risco/métodos , Idoso , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Exposição à Radiação/prevenção & controle , Lesões por Radiação/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Espanha/epidemiologia
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