RESUMEN
PURPOSE: Intensity modulated radiotherapy for prostate cancer involves daily monitoring of the positioning of the prostate, possible with cone beam CT (CBCT). It allows increased accuracy compared to readjustments but induces an increase in the time dedicated to these medical checks. The aim of the study was to evaluate the possibility of delegation of this task to the radiation therapists by comparing their readjustments to the doctors. PATIENTS AND METHODS: Five consecutive patients treated with radiation for prostate cancer (76Gy) were analysed. All had a daily CBCT for position control. The movements of the prostate relative to the bony part, the positional variations of the prostate measured by the radiation therapists and the doctors and medical time required to analyse imagery (filling of the rectum and bladder and perform a recalibration) were measured. RESULTS: One hundred seventy-six CBCT were analysed or 980 steps in the three axes. The movements of the prostate relative to bony part were respectively at least 5mm in 19%, 7% and 3% in the anterior-posterior, upper-lower and right-left axes. Changes readjustments between radiation therapists and doctors were in 95% of cases at the most 4mm in the anterior-posterior and upper-lower axis, and 3mm in the left-right axis. The time for medical use of the CBCT averaged 8min 40 [4 to 22min]. CONCLUSION: The daily readjustment on the prostate using CBCT may be delegated to radiation therapists with acceptable concordance of less than 4mm for 95% of measurements. An initial and ongoing training will ensure treatment safety.
Asunto(s)
Técnicos Medios en Salud , Tomografía Computarizada de Haz Cónico , Posicionamiento del Paciente , Próstata/diagnóstico por imagen , Neoplasias de la Próstata/radioterapia , Planificación de la Radioterapia Asistida por Computador , Radioterapia de Intensidad Modulada/métodos , Anciano , Eficiencia , Humanos , Masculino , Persona de Mediana Edad , Órganos en Riesgo , Rol del Médico , Dosificación Radioterapéutica , Factores de TiempoRESUMEN
PURPOSE: To evaluate the surgical possibility following concomitant chemoradiotherapy for inflammatory breast cancer, after unsucessful neoadjuvant chemotherapy. PATIENTS AND METHODS: The data from ten patients with inflammatory breast cancer treated between 1996 and 2010 by concomitant chemoradiotherapy after unsucessful neoadjuvant chemotherapy were analysed. All patients had an invasive carcinoma. All patients received a neoadjuvant chemotherapy, including anthracyclin, six patients received taxan and one received trastuzumab. Radiotherapy was delivered to the breast and regional lymph nodes in all patients at a dose of 50Gy; a boost of 20Gy was delivered to one patient. Concomitant chemotherapy was based on weekly cisplatin for six patients, on cisplatin and 5-fluorouracil the first and last weeks of radiotherapy for four patients. RESULTS: The median follow-up for all patients was 44 months. Mastectomy was performed in nine patients. Two- and 5-year overall survival rates were respectively 70 % and 60 %. Median local recurrence delay was 5 months; six patients died (all from cancer), seven developped metastasis. Grade 1 and 2 epithelite was respectively observed in six and two patients, grade 2 renal toxicity in three patients, grade 2 neutropenia in one patient. CONCLUSION: Concomitant chemoradiotherapy for inflammatory breast cancer after unsucessful neoadjuvant chemotherapy may control the disease in some patients and lead to mastectomy. These results have to be confirmed through a multicentric study with more patients.
Asunto(s)
Quimioradioterapia , Neoplasias Inflamatorias de la Mama/terapia , Terapia Recuperativa , Adulto , Anciano , Femenino , Humanos , Neoplasias Inflamatorias de la Mama/tratamiento farmacológico , Persona de Mediana Edad , Insuficiencia del TratamientoRESUMEN
The various image-guided radiotherapy techniques raise the question of how to achieve the control of patient positioning before irradiation session and sharing of tasks between radiation oncologists and radiotherapy technicians. We have put in place procedures and operating methods to make a partial delegation of tasks to radiotherapy technicians and secure the process in three situations: control by orthogonal kV imaging (kV-kV) of bony landmarks, control by kV-kV imaging of intraprostatic fiducial goldmarkers and control by cone beam CT (CBCT) imaging for prostate cancer. Significant medical overtime is required to control these three IGRT techniques. Because of their competence in imaging, these daily controls can be delegated to radiotherapy technicians. However, to secure the process, initial training and regular evaluation are essential. The analysis of the comparison of the use of kV/kV on bone structures allowed us to achieve a partial delegation of control to radiotherapy technicians. Controlling the positioning of the prostate through the use and automatic registration of fiducial goldmarkers allows better tracking of the prostate and can be easily delegated to radiotherapy technicians. The analysis of the use of daily cone beam CT for patients treated with intensity modulated irradiation is underway, and a comparison of practices between radiotherapy technicians and radiation oncologists is ongoing to know if a partial delegation of this control is possible.
Asunto(s)
Delegación Profesional , Neoplasias de la Próstata/radioterapia , Radioterapia Guiada por Imagen/métodos , Tomografía Computarizada de Haz Cónico , Humanos , Masculino , Posicionamiento del Paciente , Radiografía IntervencionalRESUMEN
The aim of this article is to present the determination and the delineation of target volumes for oral cavity and oropharyngeal carcinomas treated with intensity-modulated irradiation. The delineation on the computerized tomography scanner (CT scan) requires a precise method because of the complexity of the head-and-neck anatomy. Different elements are necessary: clinical examination, diagram of the initial tumor, surgical and pathological reports and medical imaging (CT scan, magnetic resonance imaging and fluorodeoxyglucose positron emission tomography). The clinical target volumes, the planning target volumes, the organs at risk and the planning organs at risk volumes are discussed. The concept of selectivity of the potential subclinical disease near the primary tumour and the selection of neck nodal targets are specified according to the literature.
Asunto(s)
Neoplasias de la Boca/radioterapia , Neoplasias Orofaríngeas/radioterapia , Radioterapia de Intensidad Modulada , Diagnóstico por Imagen , Humanos , Neoplasias de la Boca/patología , Órganos en Riesgo , Neoplasias Orofaríngeas/patología , Planificación de la Radioterapia Asistida por ComputadorRESUMEN
PURPOSE: Daily set up of patients with prostate cancer using orthogonal kV/kV imaging and weekly set up control require 1h to 1h30 of off line revision by a radio-oncologist per day and per accelerator. The aim of this study was to evaluate the possibility to delegate this control to radiation therapists. MATERIAL AND METHODS: The files of 33 patients (including 13 with prostate cancer) treated from November 2010 to February 2011 on a Varian™ Clinac IX accelerator with an OBI™ system were evaluated. Radiation therapists made the daily kV/kV imaging. Radiation therapists made the online control by kV/kV for patient repositioning and radio-oncologists made the offline reviews; the results were compared and analysed (seven radiation therapists and seven radio-oncologists). For an isocentre displacement of 5mm, the radiation therapist had to call the radio-oncologist to make a medical decision (treatment or patient displacement). The difference of measures and the concordance of decisions between radiation therapists and radio-oncologists were calculated. RESULTS: Five hundred and fifty-six measures were made for 33 treatments, including 226 measures for prostate cancer treatment. The difference of measures between radiation therapists and radio-oncologists was 3mm or less in 93.7% for all treatments and 96.2% for prostate cancer treatment. The concordance of decision between radiation therapists and radio-oncologists for measures up to 4mm was 97% (CI95±2%) vs. 57% (CI95±10%) for measures equal to or higher than 5mm (P<0.0001). CONCLUSION: Radiation therapists are able to do daily set up using kV/kV on the bony structures of patients with prostate cancer, with a risk of disagreement higher than 3mm less than 4%. The weekly set up controls (different primaries) can be delegated to the radiation therapists, subject to an accurate procedure using a medical alert for a given threshold. Training and competence certification are required to secure the process.
Asunto(s)
Adenocarcinoma/diagnóstico por imagen , Antropometría/métodos , Imagenología Tridimensional/métodos , Aceleradores de Partículas/instrumentación , Posicionamiento del Paciente , Delegación al Personal , Neoplasias de la Próstata/diagnóstico por imagen , Oncología por Radiación , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia de Intensidad Modulada/métodos , Tecnología Radiológica , Adenocarcinoma/radioterapia , Antropometría/instrumentación , Artefactos , Toma de Decisiones , Humanos , Imagenología Tridimensional/instrumentación , Masculino , Movimiento (Física) , Neoplasias/diagnóstico por imagen , Neoplasias/radioterapia , Variaciones Dependientes del Observador , Huesos Pélvicos/diagnóstico por imagen , Neoplasias de la Próstata/radioterapia , Dosis de Radiación , Intensificación de Imagen Radiográfica , Planificación de la Radioterapia Asistida por Computador/instrumentación , Reproducibilidad de los Resultados , Robótica , Carga Tumoral , Carga de TrabajoRESUMEN
In the treatment of brain metastases, whole brain radiotherapy can be carried out according two distinct methods: one using multileaf collimator for field shaping and protection of organs at risk, and a second one is to make a rotation of the field to avoid the eyes. The aim of the study was to compare for 10 patients the dose distributions at organs at risk for each method. Patients received 30 Gy in 10 fractions. Except for parotid glands, the dose received by organs at risk and the planning target volume was the same with each method. For whole brain radiotherapy, excluding the cisterna cerebellomedullaris, the mean parotid dose was 9.63 Gy using the multileaf collimator versus 12.32 Gy using the field rotation (P=0.04). For whole brain radiotherapy including the cisterna cerebellomedullaris, the mean parotid dose was 11.12 Gy using the multileaf collimator versus 20.06 Gy using field rotation (P<0.001). Using the multileaf collimator seems recommended for whole brain radiotherapy, to reduce the dose to the parotids.
Asunto(s)
Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundario , Glándula Parótida/efectos de la radiación , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radioterapia/métodos , Dosificación RadioterapéuticaRESUMEN
There is still an ongoing debate whether or not electronic stun devices (ESDs) induce cardiac fibrillation. To assess the ventricular fibrillation risk of law enforcing electronic control devices, quantitative estimates of cardiac electric current densities induced by delivered electric pulses are essential. Numerical simulations were performed with the finite integration technique and the anatomical model of a standardized European man (NORMAN) segmented into 2 mm voxels and 35 different tissues. The load-dependent delivery of TASER X-26 pulses has been taken into account. Cardiac exposure to electric current densities of vertically and horizontally aligned dart electrodes was quantified and different hit scenarios compared. Since fibrillation thresholds critically depend on exposed volume, the provided quantitative data are essential for risk assessment. The maximum cardiac rms current densities amounted to 7730 A m(-2). Such high current densities and exposed cardiac volumes do not exclude ventricular fibrillation.
Asunto(s)
Conductividad Eléctrica , Estimulación Eléctrica/instrumentación , Corazón , Aplicación de la Ley/métodos , Modelos Anatómicos , Adulto , Humanos , MasculinoRESUMEN
BACKGROUND: Information dissemination is a mandated, but understudied, requirement of occupational and environmental health laws and voluntary initiatives. Research is needed on the factors that enhance and limit the development, transfer, and use of occupational safety and health information (OSH). Contemporary changes in the workforce, workplaces, and the nature of work will require new emphasis on the dissemination of information to foster prevention. METHODS: Legislative and regulatory requirements and voluntary initiatives for dissemination of OSH information were identified and assessed. Literature on information dissemination was reviewed to identify important issues and useful approaches. RESULTS: More than 20 sections of laws and regulations were identified that mandated dissemination of occupational and environmental safety and health information. A four-stage approach for tracking dissemination and considering the flow of information was delineated. Special areas of dissemination were identified: the information needs of the changing workforce, new and young workers; small businesses; and workers with difficulty in understanding or reading English. CONCLUSIONS: We offer a framework for dissemination of OSH information and underscore the need to focus on the extent to which decision-makers and others receive and use such information. More solid data are also needed on current investments in disseminating, diffusing and applying OSH information and on the utility of that information. Am. J. Ind. Med. 44:515-531, 2003. Published 2003 Wiley-Liss, Inc.
Asunto(s)
Difusión de la Información/legislación & jurisprudencia , Difusión de la Información/métodos , Salud Laboral/legislación & jurisprudencia , Humanos , Estados UnidosRESUMEN
Common wave-front sensors such as the Hartmann or curvature sensor provide measurements of the local gradient or Laplacian of the wave front. The expression of wave fronts in terms of a set of orthogonal basis functions thus generally leads to a linear wave-front-estimation problem in which modal cross coupling occurs. Auxiliary vector functions may be derived that effectively restore the orthogonality of the problem and enable the modes of a wave front to be independently and directly projected from slope measurements. By using variational methods, we derive the necessary and sufficient condition for these auxiliary vector functions to have minimum-error norm. For the specific case of a slope-based sensor and a basis set comprising the Zernike circular polynomials, these functions are precisely the Gavrielides functions.
RESUMEN
1. Training via the Internet (e-training) for adults must be based on the following principles: (1) learning is an active process wherein the learner constructs knowledge rather than acquires it and (2) instruction is a process of supporting this construction rather than communicating knowledge. E-training can successfully accommodate such features using available technologies. 2. Because e-training is self directed, it is uniquely adaptable to learners with different learning styles, interests, and cultural beliefs. E-training also affords flexible pacing, which is ideal for instruction aimed at both new and experienced workers. 3. As the predicted global economy becomes reality, qualified OSH personnel will be needed on a global scale. To meet new and evolving needs worldwide, professionals must have access to information and training regardless of location. E-training is the most promising approach to meeting this demand. 4. Currently, occupational safety and health e-training does not fulfill its potential. Most training programs do not encourage higher level cognition, critical thinking, or transfer of knowledge. Therefore, training effectiveness research is needed to improve the state of e-training.
Asunto(s)
Educación Continua/métodos , Capacitación en Servicio/métodos , Internet , Servicios de Salud del Trabajador , Humanos , National Institute for Occupational Safety and Health, U.S. , Estados Unidos , United States Occupational Safety and Health AdministrationRESUMEN
This study examines rates of low birth weight (LBW) in the state of Hawaii and changes in the association of LBW with socioeconomic status from 1970 to 1990. The analysis is based on aggregate data for census tracts. Rates of low birth weight were calculated for each census tract. Relative socioeconomic scores were calculated from average household income and years of education. The results show that (1) there was a decrease in the rate of low birth weight infants in Hawaii; and (2) that the correlation between socioeconomic status and low birth weight was substantially reduced, though a significant correlation remains. The paper suggests likely ceiling effects, but that the progressive public health policies and expansion of access to primary health care in Hawaii during this period played a major role in reducing the rate of low birth weight infants and in decreasing socioeconomic inequality on this important health indicator.
Asunto(s)
Indicadores de Salud , Recién Nacido de Bajo Peso , Escolaridad , Etnicidad , Hawaii/epidemiología , Humanos , Renta , Recién Nacido , Factores SocioeconómicosRESUMEN
A study has been made of a Gram-Charlier matched filter for Shack-Hartmann sensing of wave-front slopes. The method is based on modeling the point-spread function by an expansion in terms of Gauss-Hermite polynomials. We present results for several subapertureycoherence area sizes both with and without CCD read noise. A more accurate estimation of the local slopes can be achieved at low light levels in this way than with the standard first-moment estimator.
RESUMEN
INTRODUCTION: Departments of health can provide applied settings for students from academic public health programs to explore the connection of course work to real-life circumstances. Barriers exist for public health practitioners, however, that restrict their willingness to engage in joint efforts with academe. To address these barriers, they must be identified and characterized. That is, it is important for academics in public health to respect both barrier-issues and to understand underlying value constructs, if they hope to employ public health practice settings to advance their students' training. METHODS: A 100% sample of all midmanagers was surveyed at the Hawaii Department of Health by the School of Public Health. Nine clusters of "key issues for continued collaboration" were identified and rank-ordered in importance. Further analysis of the rank-orders, using multidimensional scaling, distinguished important underlying value constructs crucial to improving joint activities between the school and department. RESULTS: Working together, representatives from the Department and School identified the first three value dimensions as cooperation, implying the need for true reciprocal and equal interaction; obligation, signifying mutual responsibility and parallel investment; and, professional practice, suggesting the balanced interdigitation of research with practice. These value dimensions account for three fifths (58%) of the variance in opinion. CONCLUSIONS: Detailed analysis of these dimensions suggests that low-cost strategies improve collaboration, and foster possible consolidation, between academic and clinical public health settings. A stronger partnership between the school and the department is likely, provided the two agencies can address these issues satisfactorily. Insights from the Hawaii experience may prove useful to other academic public health practice settings. Recommendations that may improve collaboration include holding joint semi-annual meetings, a school bulletin board listing practica at the department, a public health leadership course, improved electronic communications between the school and the department, joint appointments to the two agencies, faculty release time to conduct research to improve practices at the department, and the establishment of a steering committee for the collaboration.
Asunto(s)
Relaciones Interinstitucionales , Administración en Salud Pública , Centros Médicos Académicos , Conducta Cooperativa , Curriculum , Femenino , Agencias Gubernamentales , Hawaii , Encuestas de Atención de la Salud , Humanos , Masculino , Persona de Mediana Edad , Objetivos OrganizacionalesRESUMEN
OBJECTIVE: As aerobic exercise capacity, as defined by VO2max, is associated with patient functioning and possibly prognosis in cystic fibrosis (CF), correlations between VO2max phenotype and genotype may be of value. DESIGN: Retrospective clinical series. SETTING: Cystic fibrosis referral clinic. PATIENTS: Convenience sample of 35 patients with CF consecutively referred for exercise testing. MAIN OUTCOME MEASURES: Blood samples were examined for mutations of cystic fibrosis transmembrane regulator (CFTR), Height, wight, pulmonary function, resting-energy expenditure, VO2max, and other exercise variables were assessed in each referred patient. RESULTS: Statistical comparison of 10 patients who were homozygous for the dF508 mutation of CFTR with 20 patients heterozygous for dF508 revealed no significant differences for height, weight, pulmonary function, resting-energy expenditure, VO2max, or any other exercise variables. CONCLUSIONS: These results imply a limited effect of the mutation status on overall patient functioning and prognosis. Future identification of more rare CFTR mutations and other genes and subsequent classification of patients in a manner reflective of the cellular physiology may lead to different results.
Asunto(s)
Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Fibrosis Quística/fisiopatología , Mutación/genética , Consumo de Oxígeno/genética , Fenilalanina/genética , Adolescente , Estatura , Peso Corporal , Fibrosis Quística/sangre , Fibrosis Quística/genética , Regulador de Conductancia de Transmembrana de Fibrosis Quística/sangre , Metabolismo Energético , Prueba de Esfuerzo , Femenino , Volumen Espiratorio Forzado/fisiología , Genotipo , Heterocigoto , Homocigoto , Humanos , Pulmón/fisiopatología , Masculino , Flujo Espiratorio Medio Máximo/fisiología , Ápice del Flujo Espiratorio/fisiología , Fenotipo , Esfuerzo Físico/fisiología , Pronóstico , Descanso/fisiología , Estudios Retrospectivos , Capacidad Vital/fisiologíaRESUMEN
The aim of this study was to assess results of surgery for aneurysms of the abdominal aorta in patients over 70 years of age. Survival and quality of life were used as assessment criteria. Files of 277 patients over 70 years of age who had undergone surgery for an aneurysm of the subrenal abdominal aorta between 1974 and 1992 were examined retrospectively. There were 246 men and 31 women of whom 230 were under 80 and 47 over 80 years of age. The operation was programmed in 145 cases and was an emergency procedure in 132 (45 ruptures and 87 painful fissurations). Perioperative mortality was 1.4% in programmed surgery and 19.7% in emergency surgery. Overall actuarial survival was 60.07% at 5 years and 26.04% at 10 years. Quality of life after the operation was unchanged in 56.1%, improved in 19.3% and worse in 24.6%. Surgery for aneurysm of the subrenal abdominal aorta is justified in patients over 70 years of age. It can provide satisfactory survival in good quality of life conditions.
Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Calidad de Vida , Anciano , Anciano de 80 o más Años , Aneurisma de la Aorta Abdominal/mortalidad , Femenino , Humanos , Masculino , Estudios Retrospectivos , Factores de Riesgo , Tasa de SupervivenciaRESUMEN
The public health discipline is receiving increased attention in the United States under initiatives for health care reforms. It is realized that community-wide interventions to prevent disease and promote health are more cost-effective than medical interventions to cure injury and illness. Internationally, these same realizations were embedded in the Alma Ata movement for increased primary care. To improve respect for public health professionalism, a national effort is now underway in the United States to establish minimum competencies for public health practice, and to assure that these competencies are addressed as part of professional graduate studies. Using nationally recommended competencies detailed across nine public health and a separate cross-cutting list of universal competencies, the University of Hawaii School of Public Health assessed all their courses to determine the degree each competency is addressed by each course. A four-point scale was used. Lead faculty for each course assessed the depth of coverage. For the Hawaii School of Public Health, this study identified important gaps in instruction, and possible areas of over-instruction. This information will assist the School to revise course offerings and academic/clinical posts. This approach to curriculum reform and the establishment of minimum competencies for academic public health should also prove useful to other schools in the US and elsewhere. By standardizing professional competencies, the public health profession with increase in stature and impact.
Asunto(s)
Competencia Clínica/normas , Personal de Salud/educación , Salud Pública/educación , Curriculum , Guías como Asunto , Hawaii , Humanos , Perfil Laboral , Evaluación de Necesidades , Evaluación de Programas y Proyectos de Salud , Escuelas de Salud PúblicaRESUMEN
As public health by its very nature is multi-disciplinary, it may benefit individual programs to formulate a regional network, joining researchers and academics across programs. This approach may afford extended benefits, such as the establishment of regional health surveillance systems and collaborative funding initiatives. To explore this potential, member institutions comprising the Asia-Pacific Academic Consortium for Public Health provided data to form an aggregate profile of cross-institutional expertise and resources, which was presented to Health Specialists at the Asian Development Bank. The study provided a foundation for a planned regional network. A four-pronged approach was proffered detailing concurrent aspects of development: 1) network formation and expansion, 2) research coordination, 3) cross-institutional communication and instruction, and 4) promotion of self-sufficiency. The proposed plan affords the groundwork for an improved approach to public health research and practice that builds upon the established Consortium, and encourages new horizons. Regionalization is an increasing phenomenon world wide, and should be furthered as a concept for improved public health intervention and control.
Asunto(s)
Administración en Salud Pública , Programas Médicos Regionales/organización & administración , Asia , Competencia Clínica/normas , Humanos , Evaluación de Necesidades , Islas del Pacífico , Desarrollo de Programa , Salud Pública/educación , InvestigaciónRESUMEN
The purpose of the present study was to examine the content emphasis of courses of public health administration and management (A & M) among member institutions of the Asia-Pacific Academic Consortium for Public Health (APACPH), to determine comparability of curricula across campuses. A survey of course syllabi from APACPH schools was conducted by three separate reviewers to identify topical subject matter presented in general and specialty A & M courses delivered to graduate students at each campus. Based on this review, three synthetic general content A & M courses, and one specialty A & M course (i.e. Hospital Administration) were created as a basis for intercampus cross-institutional comparisons conducted by the author. Despite the number of courses provided by the different APACPH institutions, specific content areas consistently appeared across institutions, suggesting possible foundational A & M content for public health students. In general, there was much better coverage of similar topics at the introductory level of instruction, and much greater consistency was observed across institutions that provided course work addressing the administration of hospitals. Several recommendations are made for further studies of other content areas, and for the development of minimum training content areas as a basis for cross-institutional studies.
Asunto(s)
Curriculum , Administración en Salud Pública/educación , Asia , Islas del Pacífico , SociedadesRESUMEN
We present the results of a pupil-masking experiment that uses the Sun as the source object. The goal of our experiment was a proof-of-concept validation for a Fizeau (image-plane) interferometric beam combination with a complex source that overfilled the field of view. We employed a phase-diversity technique to measure the optical phases required to recover the instantaneous optical transfer function for the masked pupil. We used a Wiener filter to deconvolve the dirty images.
RESUMEN
The use of multiple aperture ground interferometers to measure directly the diameters of resolvable stars or to determine the separations and position angles of compact multiple star systems is well established in the literature. The general utility of this technique for producing catalogs of such observations, however, is fundamentally constrained by such noise processes as shot noise, detector dark current, and background radiation, all of which limit interferometric sensitivity. We review the various sensitivity limitations affecting low light level Michelson amplitude interferometry for these applications and calculate the wavelength-dependent detection thresholds as expressed in limiting stellar visual magnitudes that can be so achieved.