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1.
Journal of Southern Medical University ; (12): 1035-1040, 2023.
Artículo en Chino | WPRIM | ID: wpr-987019

RESUMEN

OBJECTIVE@#To identify the problems in clinical radiotherapy planning for cervical cancer through quantitative evaluation of the radiotherapy plans to improve the quality of the plans and the radiotherapy process.@*METHODS@#We selected the clinically approved and administered radiotherapy plans for 227 cervical cancer patients undergoing external radiotherapy at Sun Yat-sen University Cancer Center from May, 2019 to January, 2022. These plans were transferred from the treatment planning system to the Plan IQTM workstation. The plan quality metrics were determined based on the guidelines of ICRU83 report, the GEC-ESTRO Working Group, and the clinical requirements of our center and were approved by a senior clinician. The problems in the radiotherapy plans were summarized and documented, and those with low scores were re-planned and the differences were analyzed.@*RESULTS@#We identified several problems in the 277 plans by quantitative evaluation. Inappropriate target volume selection (with scores < 60) in terms of GTV, PGTV (CI) and PGTV (V66 Gy) was found in 10.6%, 65.2%, and 1% of the plans, respectively; and the PGTV (CI), GTV, and PCTV (D98%, HI) had a score of 0 in 0.4%, 10.1%, 0.4%, 0.4% of the plans, respectively. The problems in the organs at risk (OARs) involved mainly the intestines (the rectum, small intestine, and colon), found in 20.7% of the plans, and in occasional cases, the rectum, small intestine, colon, kidney, and the femoral head had a score of 0. Senior planners showed significantly better performance than junior planners in PGTV (V60 Gy, D98%), PCTV (CI), and CTV (D98%) (P≤0.046) especially in terms of spinal cord and small intestine protection (P≤0.034). The bowel (the rectum, small intestine and colon) dose was significantly lower in the prone plans than supine plans (P < 0.05), and targets coverage all met clinical requirements. Twenty radiotherapy plans with low scores were selected for re-planning. The re-planned plans had significantly higher GTV (Dmin) and PTV (V45 Gy, D98%) (P < 0.05) with significantly reduced doses of the small intestines (V40 Gy vs V30 Gy), the colon (V40 Gy vs V30 Gy), and the bladder (D35%) (P < 0.05).@*CONCLUSION@#Quantitative evaluation of the radiotherapy plans can not only improve the quality of radiotherapy plan, but also facilitate risk management of the radiotherapy process.


Asunto(s)
Humanos , Femenino , Neoplasias del Cuello Uterino/radioterapia , Recto , Colon , Riñón , Órganos en Riesgo
2.
Chinese Journal of Medical Instrumentation ; (6): 132-136, 2022.
Artículo en Chino | WPRIM | ID: wpr-928873

RESUMEN

CT image based organ segmentation is essential for radiotherapy treatment planning, and it is laborious and time consuming to outline the endangered organs and target areas before making radiation treatment plans. This study proposes a fully automated segmentation method based on fusion convolutional neural network to improve the efficiency of physicians in outlining the endangered organs and target areas. The CT images of 170 postoperative cervical cancer stage IB and IIA patients were selected for network training and automatic outlining of bladder, rectum, femoral head and CTV, and the neural network was used to localize easily distinguishable vessels around the target area to achieve more accurate outlining of CTV.


Asunto(s)
Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Redes Neurales de la Computación , Órganos en Riesgo , Pelvis , Tomografía Computarizada por Rayos X , Neoplasias del Cuello Uterino/cirugía
3.
Chinese Journal of Medical Instrumentation ; (6): 108-113, 2022.
Artículo en Chino | WPRIM | ID: wpr-928869

RESUMEN

To study an automatic plan(AP) method for radiotherapy after breast-conserving surgery based on TiGRT system and and compare with manual plan (MP). The dosimetry parameters of 10 patients and the evaluation of scoring table were analyzed, it was found that the targets dose of AP were better than that of MP, but there was no statistical difference except for CI, The V5, V20 and V30 of affected lungs and whole lungs in AP were lower than all that in MP, the Dmean of hearts was slightly higher than that of MP, but the difference was not statistically significant, the MU of AP was increase by 16.1% compared with MP, the score of AP evaluation was increase by 6.1% compared with MP. So the AP could be programmed and automated while ensuring the quality of the plan, and can be used to design the plans for radiotherapy after breast-conserving surgery.


Asunto(s)
Femenino , Humanos , Neoplasias de la Mama/cirugía , Mastectomía Segmentaria , Órganos en Riesgo , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Radioterapia de Intensidad Modulada
5.
Journal of Biomedical Engineering ; (6): 311-316, 2020.
Artículo en Chino | WPRIM | ID: wpr-828165

RESUMEN

When applying deep learning to the automatic segmentation of organs at risk in medical images, we combine two network models of Dense Net and V-Net to develop a Dense V-network for automatic segmentation of three-dimensional computed tomography (CT) images, in order to solve the problems of degradation and gradient disappearance of three-dimensional convolutional neural networks optimization as training samples are insufficient. This algorithm is applied to the delineation of pelvic endangered organs and we take three representative evaluation parameters to quantitatively evaluate the segmentation effect. The clinical result showed that the Dice similarity coefficient values of the bladder, small intestine, rectum, femoral head and spinal cord were all above 0.87 (average was 0.9); Jaccard distance of these were within 2.3 (average was 0.18). Except for the small intestine, the Hausdorff distance of other organs were less than 0.9 cm (average was 0.62 cm). The Dense V-Network has been proven to achieve the accurate segmentation of pelvic endangered organs.


Asunto(s)
Humanos , Algoritmos , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Redes Neurales de la Computación , Órganos en Riesgo , Pelvis , Tomografía Computarizada por Rayos X
6.
Journal of Southern Medical University ; (12): 491-498, 2020.
Artículo en Chino | WPRIM | ID: wpr-828099

RESUMEN

OBJECTIVE@#To establish an algorithm based on 3D convolution neural network to segment the organs at risk (OARs) in the head and neck on CT images.@*METHODS@#We propose an automatic segmentation algorithm of head and neck OARs based on V-Net. To enhance the feature expression ability of the 3D neural network, we combined the squeeze and exception (SE) module with the residual convolution module in V-Net to increase the weight of the features that has greater contributions to the segmentation task. Using a multi-scale strategy, we completed organ segmentation using two cascade models for location and fine segmentation, and the input image was resampled to different resolutions during preprocessing to allow the two models to focus on the extraction of global location information and local detail features respectively.@*RESULTS@#Our experiments on segmentation of 22 OARs in the head and neck indicated that compared with the existing methods, the proposed method achieved better segmentation accuracy and efficiency, and the average segmentation accuracy was improved by 9%. At the same time, the average test time was reduced from 33.82 s to 2.79 s.@*CONCLUSIONS@#The 3D convolution neural network based on multi-scale strategy can effectively and efficiently improve the accuracy of organ segmentation and can be potentially used in clinical setting for segmentation of other organs to improve the efficiency of clinical treatment.


Asunto(s)
Humanos , Cabeza , Procesamiento de Imagen Asistido por Computador , Cuello , Redes Neurales de la Computación , Órganos en Riesgo , Tomografía Computarizada por Rayos X
7.
Journal of Southern Medical University ; (12): 1579-1586, 2020.
Artículo en Chino | WPRIM | ID: wpr-880792

RESUMEN

OBJECTIVE@#To investigate the accuracy of automatic segmentation of organs at risk (OARs) in radiotherapy for nasopharyngeal carcinoma (NPC).@*METHODS@#The CT image data of 147 NPC patients with manual segmentation of the OARs were randomized into the training set (115 cases), validation set (12 cases), and the test set (20 cases). An improved network based on three-dimensional (3D) Unet was established (named as AUnet) and its efficiency was improved through end-to-end training. Organ size was introduced as a priori knowledge to improve the performance of the model in convolution kernel size design, which enabled the network to better extract the features of different organs of different sizes. The adaptive histogram equalization algorithm was used to preprocess the input CT images to facilitate contour recognition. The similarity evaluation indexes, including Dice Similarity Coefficient (DSC) and Hausdorff Distance (HD), were calculated to verify the validity of segmentation.@*RESULTS@#DSC and HD of the test dataset were 0.86±0.02 and 4.0±2.0 mm, respectively. No significant difference was found between the results of AUnet and manual segmentation of the OARs (@*CONCLUSIONS@#AUnet, an improved deep learning neural network, is capable of automatic segmentation of the OARs in radiotherapy for NPC based on CT images, and for most organs, the results are comparable to those of manual segmentation.


Asunto(s)
Humanos , Bases de Datos Factuales , Procesamiento de Imagen Asistido por Computador , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Órganos en Riesgo , Tomografía Computarizada por Rayos X
8.
Rev. medica electron ; 41(3): 641-654, mayo.-jun. 2019. tab, graf
Artículo en Español | LILACS, CUMED | ID: biblio-1094073

RESUMEN

RESUMEN Introducción: la toxicidad de los fármacos es compleja y difícilmente valorable, por la cantidad de factores que intervienen en su producción, como modo de aparición, duración y gravedad de las reacciones adversas. La importancia de estas reacciones está dada por la frecuencia y gravedad con que un fármaco o familia de fármacos las producen. Objetivo: caracterizar las principales reacciones adversas que provocan los medicamentos, los grupos de edades con más riesgos, los sistemas de órganos que se afectan, la frecuencia, imputabilidad y la intensidad de las mismas. Materiales y métodos: estudio observacional, descriptivo, de serie de casos en farmacovigilancia. El universo fue las reacciones adversas de los 10 fármacos más notificados por la Unidad Coordinadora Provincial de Farmacovigilancia en Matanzas, en el periodo 2014-2017. Se estudiaron las variables: medicamentos, grupo farmacológico, datos demográficos, nivel de atención, tipo de efecto adverso, intensidad, imputabilidad y frecuencia. Resultados: se notificaron 10 fármacos con 2 216 reacciones. La vacuna pentavalente fue la más notificada, con un 17,6 %, seguido por la amoxicilina y las penicilinas. Predominó el sexo femenino con 1 279 reportes, (59,1 %) y los adultos, con 1 010 notificaciones, (46,6 %). La atención primaria de salud fue la de mayor número de notificaciones, 2 082 reportes, (96,1 %). Las principales reacciones fueron: la erupción cutánea, la fiebre y la urticaria. Predominaron reacciones moderadas; 1 972 reportes, (91,1 %), aquellas clasificadas como probables, 1 887 reportes, (87,1 %) y las frecuentes con 1 284 reportes, (59,2 %). Conclusiones: el sistema de farmacovigilancia en la provincia proporcionó sistemáticamente información sobre la seguridad de los medicamentos, lo que permitió el conocimiento de la relación beneficio-riesgo de los medicamentos presentes en el mercado, así como los más usados.


ABSTRACT Introduction: drugs toxicity is complex and of difficult assessment, due to the quantity of factors intervening in its production, like emergency way, duration, and seriousness of the adverse reactions. The importance of these reactions is given by the frequency and seriousness a drug or a drug family produces them. Objective: to characterize the main adverse reactions caused by medicines, the age groups having higher risk, the most affec6ted systems of organs, frequency, imputability and intensity. Material and methods: descriptive, observational study of a series of cases in pharmacovigilance. The universe was the adverse reactions of the ten drugs most reported by the Provincial Coordinating Unit of Pharmacovigilance in the period 2014-2017. The studied variables were: drugs, pharmacological group, demographic data, health care level, kind of adverse effect, intensity, imputability and frequency. Results: ten drugs were reported with 2 216 reactions. The pentavalent vaccine was the most reported one, with 17.6 %, followed by amoxicillin and penicillin. There was a predominance of the female sex with 1 279 reports (59.1 %), and adult people with 1 010 reports (46.6 %). The highest number of reports was made by the primary health care, 2 082 (96.1 %). The main reactions were skin rash, fever and urticaria. There was a predominance of mild reactions: 1 972 reports (91.1 %); reactions classified as probable: 1 887 reports (87.1 %): ands frequent ones: 1 284 reports (59.2 %). Conclusions: the pharmacovigilance system in the province systematically provided information on drugs´ safeness that allowed knowing the benefit-risk relation of the medicines that are in the market, and also which are the most used ones.


Asunto(s)
Humanos , Femenino , Adulto , Penicilinas/efectos adversos , Medición de Riesgo , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Órganos en Riesgo , Farmacovigilancia , Amoxicilina/efectos adversos , Urticaria/diagnóstico , Epidemiología Descriptiva , Exantema Súbito/diagnóstico , Fiebre/diagnóstico , Estudio Observacional
9.
Radiation Oncology Journal ; : 254-258, 2019.
Artículo | WPRIM | ID: wpr-786565

RESUMEN

PURPOSE: Deep inspiration breath hold (DIBH) is a well-established technique that enables efficient cardiac sparing in patients with left-sided breast cancer. The aim of the current study was to determine if DIBH is effective for reducing radiation exposure of of liver and other organs at risk in right breast radiotherapy (RT).MATERIALS AND METHODS: Twenty patients with right-sided breast cancer were enrolled in this study. Three-dimensional conformal RT plans were generated for each patient, with two different computed tomography scans of free breathing (FB) and DIBH. Nodes were contoured according to the Radiation Therapy Oncology Group contouring guidelines. Dose-volume histograms for the target volume coverage and organs at risk were evaluated and analyzed.RESULTS: DIBH plans showed significant reduction in mean liver dose (5.59 ± 2.07 Gy vs. 2.54 ± 1.40 Gy; p = 0.0003), V(20Gy) (148.38 ± 73.05 vs. 64.19 ± 51.07 mL; p = 0.0003) and V(10Gy) (195.34 ± 93.57 vs. 89.81 ± 57.28 mL; p = 0.0003) volumes compared with FB plans. Right lung doses were also significantly reduced in DIBH plans. Heart and left lung doses showed small but statistically significant improvement with application of the DIBH technique.CONCLUSION: We report that the use of DIBH for right-sided breast cancer significantly reduces the radiation doses to the liver, lungs, and heart.


Asunto(s)
Humanos , Neoplasias de la Mama , Mama , Corazón , Hígado , Pulmón , Órganos en Riesgo , Exposición a la Radiación , Radioterapia , Respiración , Neoplasias de Mama Unilaterales
10.
Radiation Oncology Journal ; : 127-133, 2019.
Artículo en Inglés | WPRIM | ID: wpr-760998

RESUMEN

PURPOSE: The aim of this study was to identify volume changes and dose variations of rectum and bladder during radiation therapy in prostate cancer (PC) patients. MATERIALS AND METHODS: We analyzed 20 patients with PC treated with helical tomotherapy. Daily image guidance was performed. We re-contoured the entire bladder and rectum including its contents as well as the organ walls on megavoltage computed tomography once a week. Dose variations were analyzed by means of Dmedian, Dmean, Dmax, V₁₀ to V₇₅, as well as the organs at risk (OAR) volume. Further, we investigated the correlation between volume changes and changes in Dmean of OAR.


Asunto(s)
Humanos , Órganos en Riesgo , Próstata , Neoplasias de la Próstata , Radioterapia Guiada por Imagen , Radioterapia de Intensidad Modulada , Recto , Vejiga Urinaria
11.
Radiation Oncology Journal ; : 134-142, 2019.
Artículo en Inglés | WPRIM | ID: wpr-760997

RESUMEN

PURPOSE: The aim is to study the dependence of deformable based auto-segmentation of head and neck organs-at-risks (OAR) on anatomy matching for a single atlas based system and generate an acceptable set of contours. METHODS: A sample of ten patients in neutral neck position and three atlas sets consisting of ten patients each in different head and neck positions were utilized to generate three scenarios representing poor, average and perfect anatomy matching respectively and auto-segmentation was carried out for each scenario. Brainstem, larynx, mandible, cervical oesophagus, oral cavity, pharyngeal muscles, parotids, spinal cord, and trachea were the structures selected for the study. Automatic and oncologist reference contours were compared using the dice similarity index (DSI), Hausdroff distance and variation in the centre of mass (COM). RESULTS: The mean DSI scores for brainstem was good irrespective of the anatomy matching scenarios. The scores for mandible, oral cavity, larynx, parotids, spinal cord, and trachea were unacceptable with poor matching but improved with enhanced bony matching whereas cervical oesophagus and pharyngeal muscles had less than acceptable scores for even perfect matching scenario. HD value and variation in COM decreased with better matching for all the structures. CONCLUSION: Improved anatomy matching resulted in better segmentation. At least a similar setup can help generate an acceptable set of automatic contours in systems employing single atlas method. Automatic contours from average matching scenario were acceptable for most structures. Importance should be given to head and neck position during atlas generation for a single atlas based system.


Asunto(s)
Humanos , Tronco Encefálico , Neoplasias de Cabeza y Cuello , Cabeza , Laringe , Mandíbula , Métodos , Boca , Cuello , Órganos en Riesgo , Músculos Faríngeos , Radioterapia , Médula Espinal , Tráquea
12.
Rev. medica electron ; 40(4): 1197-1206, jul.-ago. 2018. ilus
Artículo en Español | LILACS, CUMED | ID: biblio-961292

RESUMEN

RESUMEN La enfermedad relacionada con IgG4 (ER-IgG4), es una enfermedad autoinmune multisistémica caracterizada por lesiones fibroesclerosantes inflamatorias formadoras de masas o pseudotumores, concentraciones elevadas de IgG4 séricas e infiltración tisular extensa por células plasmáticas IgG4 positivas. Incluye numerosas entidades que previamente se consideraban órgano-específicas. Puede afectar prácticamente a cualquier órgano, siendo los más afectados páncreas, glándulas salivales, glándulas lacrimales, ganglios linfáticos, retroperitoneo y riñones. El diagnóstico se realiza mediante una combinación de hallazgos clínicos, serológicos, imagenológicos e histopatológicos. Tiene pronóstico reservado pero con un diagnóstico precoz se logra el control y en ocasiones la regresión de la enfermedad, aunque tiende a presentar recaídas. Es una entidad infradiagnosticada debido en parte, a que fue caracterizada recientemente. Se presentan dos casos que forman parte del espectro que abarca esta entidad, la tiroiditis de Riedel y la fibrosis retroperitoneal, que una vez diagnosticados respondieron inicialmente a la terapéutica con altas dosis de corticoides (AU).


ABSTRACT The disease related to IgG4 (ER-IgG4 in Spanish) is a multi-systemic, autoimmune disease characterized by inflammatory fibro-sclerotizing lesions forming masses or pseudo tumors, high concentrations of serum IgG4 and extensive tissue infiltrations by IgG4-positive plasma cells. It includes several entities previously considered organ-specific ones. It can affect almost any organ, being pancreas, salivary glands, lacrimal glands, lymphatic ganglion, retroperineum and kidneys the most affected ones. The diagnosis is made through combining clinical, serologic, imaging and histopathological findings. It has a reserved prognosis but with an early diagnosis its control is reached, and occasionally also the disease’s remission, although it tends to have relapses. It is an underdiagnosed disease, partially due to its recent characterization. We present two cases entering the range covered by this disease, the Riedel’s thyroiditis and retroperitoneal fibrosis, both initially answering to therapy with high doses of corticoids after diagnosis (AU).


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Anciano , Células Plasmáticas , Enfermedad Relacionada con Inmunoglobulina G4/epidemiología , Pronóstico , Enfermedad/clasificación , Diagnóstico Precoz , Órganos en Riesgo/patología , Enfermedad Relacionada con Inmunoglobulina G4/diagnóstico
13.
Rev. Soc. Cardiol. Estado de Säo Paulo ; 28(3): 254-259, jul.-ago. 2018. tab, graf
Artículo en Inglés, Portugués | LILACS | ID: biblio-916417

RESUMEN

As situações clínicas de aumento súbito da pressão arterial (PA) que caracterizam as crises hipertensivas são comuns na prática clínica, principalmente nas consultas realiza-das no pronto atendimento, portanto, o diagnóstico adequado é essencial para o melhor tratamento e desfecho clínico. A crise hipertensiva é definida pelo aumento súbito na PA (≥180 /120 mmHg) e a necessidade da redução agressiva da PA depende da gravidade da situação clinica associada. A presença de lesões novas ou progressivas em órgãos-alvo e risco iminente de morte definem as emergências hipertensivas que requerem tratamento imediato visando a rápida redução da pressão arterial, porém, não, necessariamente, a níveis normais. Na maioria dos casos, a velocidade do aumento da PA é mais importante que o nível real da PA, portanto, é fundamental que haja avaliação clínica para o diagnóstico preciso dessas condições clínicas, as quais incluem encefalopatia hipertensiva, síndromes coronarianas agudas, edema agudo dos pulmões, acidente vascular cerebral, dissecção de aorta e eclampsia. As metas para diminuição da PA para as emergências hipertensivas, de acordo com o órgão-alvo envolvido, são revisadas pelas atuais diretrizes brasileiras e ame-ricanas de hipertensão. O tratamento das emergências hipertensivas inclui vasodilatadores de ação direta e bloqueadores adrenérgicos já consagrados, entretanto, evidências recentes mostram o benefício do uso de novos fármacos ainda não disponíveis em nosso meio


The clinical conditions of an acute rise in blood pressure (BP) that characterize hyperten-sive crises are common in clinical practice, particularly in consultations that take place in the emergency room. Therefore the correct diagnosis is important for the best treatment and clinical outcome. Hypertensive crisis is defined as a sudden rise in BP (≥ 180/120 mmHg), and the need for aggressive reduction of BP depends on the severity of the associated clinical situation. The presence of new or progressive target organ injury and imminent risk of death define hypertensive emergencies requiring immediate treatment aimed at rapid reduction of blood pressure, not ne-cessarily to normal levels. In most cases, the speed of the rise in BP is more important than the actual level of BP, and clinical evaluation is essential for the accurate diagnosis of these clinical conditions, which include hypertensive encephalopathy, acute coronary syndromes, pulmonary edema, stroke, aortic dissection, and eclampsia. The goals of BP reduction for hypertensive emergencies, according to the target organ involved, have been reviewed by the current Brazi-lian and American guidelines on hypertension. Treatment of hypertensive emergencies includes direct action vasodilators and adrenergic blockers, which are already well established, but recent evidence shows the benefit of the use of new drugs, not yet available in Brazil


Asunto(s)
Humanos , Masculino , Femenino , Factores de Riesgo , Hipertensión/diagnóstico , Hipertensión/terapia , Aorta , Vasodilatadores/uso terapéutico , Nitroprusiato/uso terapéutico , Ecocardiografía/métodos , Enfermedades Cardiovasculares/fisiopatología , Clonidina/uso terapéutico , Guías como Asunto/normas , Accidente Cerebrovascular , Órganos en Riesgo , Disección/métodos , Electrocardiografía/métodos , Síndrome Coronario Agudo/complicaciones , Antihipertensivos/uso terapéutico
14.
Radiation Oncology Journal ; : 332-340, 2018.
Artículo en Inglés | WPRIM | ID: wpr-741957

RESUMEN

PURPOSE: To retrospectively analyze dosimetric parameters of volumetric-modulated arc therapy (VMAT) and three-dimensional conformal radiotherapy (3D-CRT) delivered to extranodal marginal zone B-cell lymphomas of mucosa-associated lymphoid tissue in the stomach (gastric MALT lymphoma) to find out advantages of VMAT and conditions for definite benefits of VMAT. MATERIALS AND METHODS: Fifty patients with stage I-II gastric MALT lymphoma received VMAT (n = 14) or 3D-CRT (n = 36) between December 2005 and April 2018. Twenty-seven patients were categorized according to whether the planning target volume (PTV) overlaps kidney(s). Dosimetric parameters were analyzed by dose-volume histogram. RESULTS: Radiation dose to the liver was definitely lower with VMAT in terms of mean dose (p = 0.026) and V15 (p = 0.008). The V15 of the left kidney was lower with VMAT (p = 0.065). For those with PTV overlapping kidney(s), the left kidney V15 was significantly lower with VMAT. Furthermore, the closer the distance between the PTV and kidneys, the less the left kidney V15 with VMAT (p = 0.037). Delineation of kidney(s) by integrating all respiratory phases had no additional benefit. CONCLUSIONS: VMAT significantly increased monitor units, reduced treatment time and radiation dose to the liver and kidneys. The benefit of VMAT was definite in reducing the left kidney V15, especially in geometrically challenging conditions of overlap or close separation between PTV and kidney(s).


Asunto(s)
Humanos , Riñón , Hígado , Tejido Linfoide , Linfoma de Células B de la Zona Marginal , Órganos en Riesgo , Radioterapia Conformacional , Radioterapia de Intensidad Modulada , Estudios Retrospectivos , Estómago
15.
Radiation Oncology Journal ; : 241-247, 2018.
Artículo en Inglés | WPRIM | ID: wpr-741947

RESUMEN

PURPOSE: A hybrid-dynamic conformal arc therapy (HDCAT) technique consisting of a single half-rotated dynamic conformal arc beam and static field-in-field beams in two directions was designed and evaluated in terms of dosimetric benefits for radiotherapy of lung cancer. MATERIALS AND METHODS: This planning study was performed in 20 lung cancer cases treated with the VERO system (BrainLAB AG, Feldkirchen, Germany). Dosimetric parameters of HDCAT plans were compared with those of three-dimensional conformal radiotherapy (3D-CRT) plans in terms of target volume coverage, dose conformity, and sparing of organs at risk. RESULTS: HDCAT showed better dose conformity compared with 3D-CRT (conformity index: 0.74 ± 0.06 vs. 0.62 ± 0.06, p < 0.001). HDCAT significantly reduced the lung volume receiving more than 20 Gy (V20: 21.4% ± 8.2% vs. 24.5% ± 8.8%, p < 0.001; V30: 14.2% ± 6.1% vs. 15.1% ± 6.4%, p = 0.02; V40: 8.8% ± 3.9% vs. 10.3% ± 4.5%, p < 0.001; and V50: 5.7% ± 2.7% vs. 7.1% ± 3.2%, p < 0.001), V40 and V50 of the heart (V40: 5.2 ± 3.9 Gy vs. 7.6 ± 5.5 Gy, p < 0.001; V50: 1.8 ± 1.6 Gy vs. 3.1 ± 2.8 Gy, p = 0.001), and the maximum spinal cord dose (34.8 ± 9.4 Gy vs. 42.5 ± 7.8 Gy, p < 0.001) compared with 3D-CRT. CONCLUSIONS: HDCAT could achieve highly conformal target coverage and reduce the doses to critical organs such as the lung, heart, and spinal cord compared to 3D-CRT for the treatment of lung cancer patients.


Asunto(s)
Humanos , Corazón , Neoplasias Pulmonares , Pulmón , Órganos en Riesgo , Radioterapia , Radioterapia Conformacional , Médula Espinal
16.
Journal of Southern Medical University ; (12): 1344-1348, 2018.
Artículo en Chino | WPRIM | ID: wpr-771470

RESUMEN

OBJECTIVE@#To compare the accuracy of different methods for image registration in image-guided adaptive brachytherapy (IGABT) for cervical cancer.@*METHODS@#The last treatment planning CT images (CT1) and the first treatment planning CT images (CT2) were acquired from 15 patients with cervical cancer and registered with different match image qualities (retained/removed catheter source in images) and different match regions [target only (S Group)/ interested organ structure (M Group)/body (L Group)] in Velocity3.2 software. The dice similarity coefficient (DSC) between the clinical target volumes (CTV) of the CT1 and CT2 images (CTVCT1 and CTVCT2, respectively) and between the organs-at-risk (OAR) of the two imaging datasets (OARCT1 and OARCT2, respectively) were used to evaluate the image registration accuracy.@*RESULTS@#The auto-segmentation volume of the catheter source using Velocity software based on the CT threshold was the closest to the actual volume within the CT value range of 1700-1800 HU. In the retained group, the DSC for the OARs of was better than or equal to that of the removed group, and the DSC value of the rectum was significantly improved ( < 0.05). For comparison of different match regions, the high-risk target volume (HRCTV) and the low-risk target volume (IRCTV) had the best precision for registration of the target area, which was significantly greater than that of M group and L group ( < 0.05). The M group had better registration accuracy of the target area and the best accuracy for the OARs. The DSC values of the bladder and rectum were significantly better than those of the other two groups ( < 0.05).@*CONCLUSIONS@#The CT value range of 1700-1800 HU is optimal for automatic image segmentation using Velocity software. Automatic segmentation and shielding the volume of the catheter source can improve the image quality. We recommend the use of interested organ structures regions for image registration in image-guided adaptive brachytherapy for cervical cancer.


Asunto(s)
Femenino , Humanos , Braquiterapia , Métodos , Estándares de Referencia , Órganos en Riesgo , Diagnóstico por Imagen , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Métodos , Estándares de Referencia , Radioterapia Guiada por Imagen , Métodos , Estándares de Referencia , Programas Informáticos , Tomografía Computarizada por Rayos X , Métodos , Estándares de Referencia , Neoplasias del Cuello Uterino , Diagnóstico por Imagen , Radioterapia
17.
Journal of Korean Medical Science ; : e135-2018.
Artículo en Inglés | WPRIM | ID: wpr-714079

RESUMEN

BACKGROUND: Although intracavitary radiotherapy (ICR) is essential for the radiation therapy of cervical cancer, few institutions in Korea perform 3-dimensional (3D)-based ICR. To identify patients who would benefit from 3D-based ICR, dosimetric parameters for tumor targets and organs at risk (OARs) were compared between 2-dimensional (2D)- and 3D-based ICR. METHODS: Twenty patients with locally advanced cervical cancer who underwent external beam radiation therapy (EBRT) following 3D-based ICR were retrospectively evaluated. New 2D-based plans based on the Manchester system were developed. Tumor size was measured by magnetic resonance imaging. RESULTS: The mean high risk clinical target volume (HR-CTV) D90 value was about 10% lower for 2D- than for 3D-based plans (88.4% vs. 97.7%; P = 0.068). Tumor coverage did not differ between 2D- and 3D-based plans in patients with tumors ≤ 4 cm at the time of brachytherapy, but the mean HR-CTV D90 values in patients with tumors > 4 cm were significantly higher for 3D-based plans than for 2D-based plans (96.0% vs. 78.1%; P = 0.017). Similar results were found for patients with tumors > 5 cm initially. Other dosimetric parameters for OARs were similar between 2D- and 3D-based plans, except that mean sigmoid D2cc was higher for 2D- than for 3D-based plans (67.5% vs. 58.8%; P = 0.043). CONCLUSION: These findings indicate that 3D-based ICR plans improve tumor coverage while satisfying the dose constraints for OARs. 3D-based ICR should be considered in patients with tumors > 4 cm size at the time of brachytherapy or > 5 cm initially.


Asunto(s)
Humanos , Braquiterapia , Colon Sigmoide , Imagenología Tridimensional , Corea (Geográfico) , Imagen por Resonancia Magnética , Órganos en Riesgo , Radioterapia , Estudios Retrospectivos , Neoplasias del Cuello Uterino
18.
Rev. Pesqui. (Univ. Fed. Estado Rio J., Online) ; 9(4): 907-916, out.-dez. 2017. tab
Artículo en Inglés, Portugués | LILACS, BDENF | ID: biblio-908485

RESUMEN

Objetivo: identificar na literatura publicações sobre os fatores de risco para o olho seco em pacientes internados em Unidade de Terapia Intensiva (UTI) de adultos. Método: Realizou-se busca nas bases de dados Medical Literature Analysis and Retrieval System Online (MedLine), Cumulative Index of Nursing and Allied Health (CINAHL), Web of Knowledge, Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS), Cochrane, Instituto Brasileiro de Engenharia de Custos (IBECS) e Banco de Dados em Enfermagem (BDENF). Foram identificadas 620 publicações potencialmente elegíveis, selecionando-se, ao final, 27 publicações que atenderam aos critérios de inclusão. Essas foram analisadas por dois pesquisadores independentes, usando-se instrumento adaptado para verificar o nível de evidência. Resultado: Foram identificados 39 diferentes fatores de risco para olho seco, sendo os apontados em 50% ou mais dos estudos, o lagoftalmo (85,18%), o uso de sedativos (70,37%), a ventilação mecânica (66,66%) e o uso de bloqueadores musculares (55,55%). Conclusão:Foi encontrado somente um estudo que abordasse especificamente o problema do olho seco em pacientes críticos; estudos clínicos são necessários, a fim de se apresentar evidências científicas fortes ao problema.


Objective: to identify in peer literature publications on the risk of dry eye in patients admitted to adult intensive care units. Methods: A study in the databases MedLine, CINAHL, Web of Knowledge, LILACS, Cochrane, IBECS and BDENF was conducted. In these, 620 potentially eligible studies were found, and from those, 27 met the inclusion criteria and were selected. The studies were analyzed by two independent researchers who used an instrument adapted to identify the level of evidence of the articles. Results: 39 different risk factors for dry eye were identified; the following risk factors were found in 50% ormore of the studies: lagophthalmos (85.18%), use of sedatives (70.37%), mechanical ventilation (66.66%) and the use of neuromuscular blocking agents (55.55%). Conclusion: It was found only one studythat specifically addressed the dry eye problem in critically ill patients, further clinical studies are necessary in order to provide strong scientific evidence on the subject.


Objetivo: identificar los trabajos publicados sobre los factores de riesgo para el ojo seco en pacientes ingresados en la unidad de cuidados intensivos para adultos. Método: Fue realizada una búsqueda en las bases de datos MedLine, CINAHL, Web of Knowledge, LILACS, Cochrane, IBECS y BDENF. Se identificaron 620 artículos potencialmente elegibles, mediante la selección final de 27 publicaciones que cumplieron los criterios de inclusión. Estos fueron analizados por dos investigadores independientes, utilizando un instrumento adaptado para comprobar el nivel de evidencia. Resultados: Se identificaron 39 factores de riesgo diferentes para el ojo seco; y señaló en 50% o más de los estudios: lagoftalmos (85.18%), sedantes (70.37%), ventilación mecánica (66,66%) y el uso de bloqueo neuromuscular (55,55%). Conclusión: Sólo un estudio que aborda específicamente el problema de ojo seco se encontró en los pacientes críticamente enfermos; se necesitan estudios clínicos con el fin de proporcionar una fuerte evidencia científica al problema.


Asunto(s)
Humanos , Síndromes de Ojo Seco/complicaciones , Síndromes de Ojo Seco/diagnóstico , Síndromes de Ojo Seco/enfermería , Síndromes de Ojo Seco/prevención & control , Unidades de Cuidados Intensivos , Órganos en Riesgo , Factores de Riesgo , Brasil , Enfermedades del Aparato Lagrimal/enfermería
19.
International Journal of Radiation Research. 2017; 15 (1): 101-106
en Inglés | IMEMR | ID: emr-187501

RESUMEN

Background: Intraoral radiographs are believed to deliver low doses to patients, thus little work has been done in this regards. Considering the increment in the number of patients reporting for the examination and the probability of delayed somatic effects for accumulated low doses of X-irradiation, it is expedient to determine the doses to three critical organs eye, thyroid and parotid that are at risk during exposure


Materials and Methods: Thermoluminescent dosimeters was used to measure Entrance Surfaces Doses [ESDs] to the thyroid, eye and parotids salivary gland of 40 adult patients undergoing intra-oral radiographic examination at University College Hospital, [UCH] Ibadan, Oyo state


Results: Results indicated entrance surface doses [ESD] ranged between 0.0447 mGy to 0.3898 mGy to the thyroid, 0.0742 mGy to 0.3989 mGy to eye and 0.0467 mGy to 0.4164 mGy to the parotids for the period of study. The mean ESD +/- SD to the thyroid, parotids and eyes for male were 0.179810.081, 0.215510.109 and 0.219710.081 mGy with the female patients 0.195710.084, 0.209110.081 and 0.228010.113 mGy respectively. No statistically significant difference was found between these means


Conclusion: The doses obtained in this study were lower than the documented threshold that could cause significant damage in the various organs, not undermining stochastic effect of radiation. This study will assist in setting Diagnostic Reference Level [DRL] for intraoral radiographic imaging in Nigeria


Asunto(s)
Adulto , Adolescente , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radiografía Dental/efectos adversos , Órganos en Riesgo/efectos de la radiación , Glándula Tiroides , Glándula Parótida , Ojo , Hospitales de Enseñanza , Dosimetría Termoluminiscente , Estándares de Referencia
20.
Rev. Pesqui. (Univ. Fed. Estado Rio J., Online) ; 8(2): 4423-4434, abr.-jul.2016.
Artículo en Inglés, Portugués | LILACS, BDENF | ID: lil-784571

RESUMEN

summarizing the scientific content produced about the risk factors for corneal injury in critically ill patients in intensive care. Method: this is an integrative review of the literature conducted by question: “Which risk factors are involved in the development of corneal injury in critically ill patients in intensive care?” We searched the banks of BDENF, LILACS, SciELO and MEDLINE. The collection was performed according to the research protocol from January to April 2014. Results: the risk factors found are related to impairment of defense mechanisms, ventilation, and level of consciousness, severity and hemodynamic instability and use of specific medications. Conclusion: there was noted the scarcity of scientific papers about the subject in our country, which makes it imperative to urgent investigation into our reality, in order to demonstrate the problems of this disease...


sumarizar o conteúdo científico produzido sobre os fatores de risco para lesão na córnea em pacientes críticos na terapia intensiva. Método: trata-se de uma revisão integrativa da literatura realizada através do questionamento: “Quais fatores de risco estão envolvidos no desenvolvimento da lesão na córnea em pacientes críticos na terapia intensiva?” Pesquisou-se nas bases de dados BDENF, LILACS, SciELO e MEDLINE. A coleta foi realizada segundo protocolo de pesquisa, de janeiro a abril de 2014. Resultados: os fatores de risco encontrados relacionam-se ao comprometimento dos mecanismos de defesa, assistência ventilatória, nível de consciência, gravidade e instabilidade hemodinâmica e uso de medicações específicas. Conclusão: constatou-se a escassez de produções científicas sobre a temática em nosso país, o que torna imperativo a urgente investigação em nossa realidade para demonstrar a problemática deste agravo...


resumir el contenido científico acerca de los factores de riesgo de lesión en la córnea en pacientes críticamente enfermos en cuidados intensivos. Método: se trata de una revisión integradora realizada por la pregunta: “¿Cuáles son los factores de riesgo que estean implicados en el desarrollo de la lesión en la córnea en pacientes críticamente enfermos en cuidados intensivos?” Se realizaron búsquedas en las orillas del BDENF, LILACS, SciELO y MEDLINE. Fue realizada en el período de enero a abril de 2014. Resultados: los factores de riesgo están relacionados con el deterioro de los mecanismos de defensa, ventilación, nivel de conciencia, la gravedad y la inestabilidad hemodinámica y el uso de determinados medicamentos. Conclusión: tomó nota de la escasez de trabajos científicos acerca del tema en nuestro país, lo que hace imperativo urgente investigación de nuestra realidad, con el fin de demostrar los problemas de esta enfermedad...


Asunto(s)
Humanos , Factores de Riesgo , Literatura de Revisión como Asunto , Unidades de Cuidados Intensivos , Órganos en Riesgo , Úlcera de la Córnea/enfermería , Úlcera de la Córnea/prevención & control , Úlcera de la Córnea/terapia , Brasil
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