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In 2021, Ontario Health (Cancer Care Ontario) introduced a quality-based procedure model for the funding of radiation treatment (RT) in Ontario. This model ties reimbursement to patient care activities, ensuring equity and transparency in funding. Over 200 RT interprofessionals (oncologists, therapists and physicists) participated on 22 expert panels to establish or identify 288 evidence-based RT protocols and 672 quality expectations (QEs) to optimally deliver RT, which eventually led to the micro-costing of all protocols. Iterative review is required to ensure updated techniques and identify evolving standards of care, thereby providing the highest quality of RT care to Ontarians.
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Consenso , Humanos , Ontario , Costos y Análisis de CostoRESUMEN
A first-time survey across 15 cancer centers in Ontario, Canada, on the current practice of patient-specific quality assurance (PSQA) for intensity modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT) delivery was conducted. The objectives were to assess the current state of PSQA practice, identify areas for potential improvement, and facilitate the continued improvement in standardization, consistency, efficacy, and efficiency of PSQA regionally. The survey asked 40 questions related to PSQA practice for IMRT/VMAT delivery. The questions addressed PSQA policy and procedure, delivery log evaluation, instrumentation, measurement setup and methodology, data analysis and interpretation, documentation, process, failure modes, and feedback. The focus of this survey was on PSQA activities related to routine IMRT/VMAT treatments on conventional linacs, including stereotactic body radiation therapy but excluding stereotactic radiosurgery. The participating centers were instructed to submit answers that reflected the collective view or opinion of their department and represented the most typical process practiced. The results of the survey provided a snapshot of the current state of PSQA practice in Ontario and demonstrated considerable variations in the practice. A large majority (80%) of centers performed PSQA measurements on all VMAT plans. Most employed pseudo-3D array detectors with a true composite (TC) geometry. No standard approach was found for stopping or reducing frequency of measurements. The sole use of delivery log evaluation was not widely implemented, though most centers expressed interest in adopting this technology. All used the Gamma evaluation method for analyzing PSQA measurements; however, no universal approach was reported on how Gamma evaluation and pass determination criteria were determined. All or some PSQA results were reviewed regularly in two-thirds of the centers. Planning related issues were considered the most frequent source for PSQA failures (40%), whereas the most frequent course of action for a failed PSQA was to review the result and decide whether to proceed to treatment.
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Radiocirugia , Radioterapia de Intensidad Modulada , Canadá , Humanos , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por ComputadorRESUMEN
Diagnostic and evidential static image, video clip, and sound multimedia are captured during routine clinical care in cardiology, dermatology, ophthalmology, pathology, physiatry, radiation oncology, radiology, endoscopic procedural specialties, and other medical disciplines. Providers typically describe the multimedia findings in contemporaneous electronic health record clinical notes or associate a textual interpretative report. Visual communication aids commonly used to connect, synthesize, and supplement multimedia and descriptive text outside medicine remain technically challenging to integrate into patient care. Such beneficial interactive elements may include hyperlinks between text, multimedia elements, alphanumeric and geometric annotations, tables, graphs, timelines, diagrams, anatomic maps, and hyperlinks to external educational references that patients or provider consumers may find valuable. This HIMSS-SIIM Enterprise Imaging Community workgroup white paper outlines the current and desired clinical future state of interactive multimedia reporting (IMR). The workgroup adopted a consensus definition of IMR as "interactive medical documentation that combines clinical images, videos, sound, imaging metadata, and/or image annotations with text, typographic emphases, tables, graphs, event timelines, anatomic maps, hyperlinks, and/or educational resources to optimize communication between medical professionals, and between medical professionals and their patients." This white paper also serves as a precursor for future efforts toward solving technical issues impeding routine interactive multimedia report creation and ingestion into electronic health records.
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Sistemas de Información Radiológica , Radiología , Consenso , Diagnóstico por Imagen , Humanos , MultimediaRESUMEN
The Canadian Organization of Medical Physicists, in close partnership with the Canadian Partnership for Quality Radiotherapy has developed a series of Technical Quality Control (TQC) guidelines for radiation treatment equipment. These guidelines outline the performance objectives that equipment should meet in order to ensure an acceptable level of radiation treatment quality. The TQC guidelines have been rigorously reviewed and field tested in a variety of Canadian radiation treatment facilities. The development process enables rapid review and update to keep the guidelines current with changes in technology. This article presents the quality control guideline accelerator-integrated cone-beam systems for verification imaging that has resulted from this process.
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Tomografía Computarizada de Haz Cónico/normas , Procesamiento de Imagen Asistido por Computador/normas , Aceleradores de Partículas/instrumentación , Fantasmas de Imagen , Guías de Práctica Clínica como Asunto/normas , Control de Calidad , Informe de Investigación , Algoritmos , Canadá , Humanos , Errores Médicos/prevención & controlRESUMEN
The Canadian Organization of Medical Physicists (COMP), in close partnership with the Canadian Partnership for Quality Radiotherapy (CPQR) has developed a series of Technical Quality Control (TQC) guidelines for radiation treatment equipment. These guidelines outline the performance objectives that equipment should meet in order to ensure an acceptable level of radiation treatment quality. The TQC guidelines have been rigorously reviewed and field tested in a variety of Canadian radiation treatment facilities. The development process enables rapid review and update to keep the guidelines current with changes in technology. This announcement provides an introduction to the guidelines, describing their scope and how they should be interpreted. Details of recommended tests can be found in separate, equipment specific TQC guidelines published in the JACMP (COMP Reports), or the website of the Canadian Partnership for Quality Radiotherapy (www.cpqr.ca).
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Física Sanitaria , Errores Médicos/prevención & control , Guías de Práctica Clínica como Asunto/normas , Control de Calidad , Oncología por Radiación/organización & administración , Oncología por Radiación/normas , Informe de Investigación , Canadá , HumanosRESUMEN
A close partnership between the Canadian Partnership for Quality Radiotherapy (CPQR) and the Canadian Organization of Medical Physicist's (COMP) Quality Assurance and Radiation Safety Advisory Committee (QARSAC) has resulted in the development of a suite of Technical Quality Control (TQC) guidelines for radiation treatment equipment; they outline specific performance objectives and criteria that equipment should meet in order to assure an acceptable level of radiation treatment quality. The adopted framework for the development and maintenance of the TQCs ensures the guidelines incorporate input from the medical physics com-munity during development, measures the workload required to perform the QC tests outlined in each TQC, and remain relevant (i.e., "living documents") through subsequent planned reviews and updates. The framework includes consolidation of existing guidelines and/or literature by expert reviewers, structured stages of public review, external field-testing, and ratification by COMP. This TQC develop-ment framework is a cross-country initiative that allows for rapid development of robust, community-driven living guideline documents that are owned by the com-munity and reviewed to keep relevant in a rapidly evolving technical environment. Community engagement and uptake survey data shows 70% of Canadian centers are part of this process and that the data in the guideline documents reflect, and are influencing, the way Canadian radiation treatment centers run their technical quality control programs. For a medium-sized center comprising six linear accelerators and a comprehensive brachytherapy program, we evaluate the physics workload to 1.5 full-time equivalent physicists per year to complete all QC tests listed in this suite.
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Atención a la Salud/normas , Aceleradores de Partículas/instrumentación , Guías de Práctica Clínica como Asunto/normas , Control de Calidad , Radioterapia/instrumentación , Radioterapia/normas , HumanosRESUMEN
OBJECTIVES: There is limited guidance on how to effectively promote safety culture in health care settings. We performed a systematic review to identify interventions to promote safety culture, specifically in oncology settings. METHODS: Medical Subject Headings and text words for "safety culture" and "cancer care" were combined to conduct structured searches of MEDLINE, EMBASE, CDSR, CINAHL, Cochrane CENTRAL, PsycINFO, Scopus, and Web of Science for peer-reviewed articles published from 1999 to 2021. To be included, articles had to evaluate a safety culture intervention in an oncology setting using a randomized or nonrandomized, pre-post (controlled or uncontrolled), interrupted time series, or repeated-measures study design. The review followed PRISMA guidelines; quality of included citations was assessed using the ROBINS-I risk of bias tool. RESULTS: Eighteen articles meeting the inclusion criteria were retained, reporting on interventions in radiation (14 of 18), medical (3 of 18), or general oncology (1 of 18) settings. Articles most commonly addressed incident learning systems (7 of 18), lean initiatives (4 of 18), or quality improvement programs (3 of 18). Although 72% of studies reported improvement in safety culture, there was substantial heterogeneity in the evaluation approach; rates of reporting of adverse events (9 of 18) or Agency for Healthcare Research and Quality Safety Culture survey results (9 of 18) were the most commonly used metrics. Most of the studies had moderate (28%) or severe (67%) risk of bias. CONCLUSIONS: Despite a growing evidence base describing interventions to promote safety culture in cancer care, definitive recommendations were difficult to make because of heterogeneity in study designs and outcomes. Implementation of incident learning systems seems to hold most promise.
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Aprendizaje , Neoplasias , Administración de la Seguridad , Humanos , Neoplasias/terapia , Estados Unidos , Ensayos Clínicos como AsuntoRESUMEN
BACKGROUND AND PURPOSE: Unexpected liver volume reductions occurred during trials of liver SBRT and concurrent sorafenib. The aims were to accumulate liver SBRT doses to assess the impact of these anatomic variations on normal tissue dose parameters and toxicity. MATERIALS AND METHODS: Thirty-two patients with hepatocellular carcinoma (HCC) or metastases treated on trials of liver SBRT (30-57 Gy, 6 fractions) and concurrent sorafenib were analyzed. SBRT doses were accumulated using biomechanical deformable registration of daily cone-beam CT. Dose deviations (accumulated-planned) for normal tissues were compared for patients with liver volume reductions > 100 cc versus stable volumes, and accumulated doses were reported for three patients with grade 3-5 luminal gastrointestinal toxicities. RESULTS: Patients with reduced (N = 12) liver volumes had larger mean deviations of 0.4-1.3 Gy in normal tissues, versus -0.2-0.4 Gy for stable cases (N = 20), P > 0.05. Deviations > 5% of the prescribed dose occurred in both groups. Two HCC patients with toxicities to small and large bowel had liver volume reductions and deviations to the maximum dose of 4% (accumulated 36.9 Gy) and 3% (accumulated 33.4 Gy) to these organs respectively. Another HCC patient with a toxicity of unknown location plus tumor rupture, had stable liver volumes and deviations to luminal organs of -6% to 4.5% (accumulated < 30.5 Gy). CONCLUSION: Liver volume reductions during SBRT and concurrent sorafenib were associated with larger increases in accumulated dose to normal tissues versus stable liver volumes. These dosimetric changes may have further contributed to toxicities in HCC patients who have higher baseline risks.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Radiocirugia , Humanos , Sorafenib/efectos adversos , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Radiocirugia/efectos adversos , Dosificación RadioterapéuticaRESUMEN
PURPOSE: Commercial CT-based image-guided radiotherapy (IGRT) systems allow widespread management of geometric variations in patient setup and internal organ motion. This document provides consensus recommendations for quality assurance protocols that ensure patient safety and patient treatment fidelity for such systems. METHODS: The AAPM TG-179 reviews clinical implementation and quality assurance aspects for commercially available CT-based IGRT, each with their unique capabilities and underlying physics. The systems described are kilovolt and megavolt cone-beam CT, fan-beam MVCT, and CT-on-rails. A summary of the literature describing current clinical usage is also provided. RESULTS: This report proposes a generic quality assurance program for CT-based IGRT systems in an effort to provide a vendor-independent program for clinical users. Published data from long-term, repeated quality control tests form the basis of the proposed test frequencies and tolerances. CONCLUSION: A program for quality control of CT-based image-guidance systems has been produced, with focus on geometry, image quality, image dose, system operation, and safety. Agreement and clarification with respect to reports from the AAPM TG-101, TG-104, TG-142, and TG-148 has been addressed.
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Guías de Práctica Clínica como Asunto , Garantía de la Calidad de Atención de Salud/normas , Radioterapia Guiada por Imagen/normas , Tomografía Computarizada por Rayos X/normas , Estados UnidosRESUMEN
PURPOSE: The efficacy of MR-guided radiotherapy on a MR-LINAC (MR-L) is dependent on the geometric accuracy of its MR images over clinically relevant Fields-of-View (FOVs). Our objectives were to: evaluate gradient non-linearity (GNL) on the Elekta Unity MR-L across time via 76 weekly measurements of 3D-distortion over concentrically larger diameter spherical volumes (DSVs); quantify distortion measurement error; and assess the temporal stability of spatial distortion using statistical process control (SPC). METHODS: MR-image distortion was assessed using a large-FOV 3D-phantom containing 1932 markers embedded in seven parallel plates, spaced 25 mm × 25 mm in- and 55 mm through-plane. Automatically analyzed T1 images yielded distortions in 200, 300, 400 and 500 mm concentric DSVs. Distortion measurement error was evaluated using median absolute difference analysis of imaging repeatability tests. RESULTS: Over the measurement period absolute time-averaged distortion varied between: dr = 0.30 - 0.49 mm, 0.53 - 0.80 mm, 1.0 - 1.4 mm and 2.28 - 2.37 mm, for DSVs 200, 300, 400 and 500 mm at the 98th percentile level. Repeatability tests showed that imaging/repositioning introduces negligible error: mean ≤ 0.02 mm (max ≤ 0.3 mm). SPC analysis showed image distortion was stable across all DSVs; however, noticeable changes in GNL were observed following servicing at the one-year mark. CONCLUSIONS: Image distortion on the MR-L is in the sub-millimeter range for DSVs ≤ 300 mm and stable across time, with SPC analysis indicating all measurements remain within control for each DSV.
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Imagen por Resonancia Magnética , Aceleradores de Partículas , Imagenología Tridimensional , Imagen por Resonancia Magnética/métodos , Fantasmas de Imagen , Programas InformáticosRESUMEN
Purpose: The primary objective was to compare 3'-deoxy-3'-(18F) fluorothymidine (FLT) positron emission tomography (PET)/computed tomography (CT) uptake in 3 cohorts of stereotactic body radiation therapy (SBRT) patients: (1) pre-SBRT, (2) stable post-SBRT lung fibrosis, and (3) suspicious or proven local recurrence post-SBRT. The secondary objectives were to optimize FLT-PET imaging by comparing FLT uptake in respiratory-gated (4-dimensional) versus nongated (3-dimensional) FLT-PET scans. Methods: Patients with early-stage non-small cell lung cancer planned or treated with SBRT at the institution with radiographic findings of fibrosis or recurrence were eligible for the study. All patients underwent imaging with FLT-PET/CT before SBRT in cohort 1 and at fibrosis or recurrence in cohort 2 and 3, respectively. The planned sample size was 20 patients in each cohort, with 60 patients total. FLT-PET standardized uptake value (SUV) variables including SUVmax, SUVmean, SUVpeak, SUV50, and SUV95 were compared among the 3 cohorts using the Kruskal-Wallis test. The correlation of respiratory-gated and nongated FLT-PET SUV variables was performed using the Spearman correlation coefficient. Results: Forty-one patients were recruited for the study (20 in cohort 1, 16 in cohort 2, and 5 in cohort 3) between 2015 and 2019. The majority received a diagnosis of stage I lung cancer (86%), and the most common prescription was 48 Gy in 4 fractions (59%). Respiratory-gated FLT-PET was performed in 35 patients. The FLT SUV variables were well correlated between respiratory-gated and nongated scans (r = 0.8-1.0). The SUVpeak, SUVmean, and SUVmax were significantly lower in the fibrosis cohort compared with the recurrence and pretreatment cohorts. The SUV50 and SUV95 values in the recurrence cohort were statistically similar to the pretreatment cohort. Conclusions: FLT-PET/CT may be helpful in differentiating SBRT-related fibrosis from recurrence. Nongated FLT-PET/CT with reporting of SUVmax and SUV95 values is recommended.
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INTRODUCTION: Patients with non-small cell lung cancer (NSCLC) can experience rapid disease progression between initial staging FDG-PET scans and commencement of curative-intent radiotherapy (RT). Previous studies that estimated stage migration rates by comparing staging PET/CT and treatment-planning PET/CT images were limited by small sample sizes. METHODS: This multicenter, international study combined prospective data from five institutions for PET-staged patients with NSCLC who were intended to receive curative-intent RT. TNM status was compared for staging and RT planning scans and the probability of TNM status and overall stage migration was analyzed as a function of the interval between PET/CT scans. The impacts of N classification, overall stage, and pathology were also studied. RESULTS: Pooled data from 181 patients were analyzed. The median interval between PET/CT scans was 42 days (range, 2-208). Upstaging occurred in 32 % of patients. The overall rate of stage migration was higher for patients presenting with initial stage IIIB/IIIC disease (p = 0.006) and patients with N2-3 nodal disease (p = 0.019). Upstaging to M1 disease was significantly associated with initial stage IIIB/IIIC disease (HR = 15.2) and adenocarcinoma (HR = 10) histology. CONCLUSION: Longer intervals between imaging and treatment in patients with NSCLC were associated with high rates disease progression with consequent risks of geographic miss in RT planning and futile treatment in patients with M1 disease. Patients with more extensive initial nodal involvement and those with adenocarcinoma had the highest rates of stage migration. Dedicated RT planning PET/CT imaging is recommended, especially if >3 weeks have elapsed after initial staging.
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Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Carcinoma de Pulmón de Células no Pequeñas/patología , Fluorodesoxiglucosa F18 , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patología , Estudios Multicéntricos como Asunto , Estadificación de Neoplasias , Tomografía Computarizada por Tomografía de Emisión de Positrones , Tomografía de Emisión de Positrones , Estudios Prospectivos , Radiofármacos , Tomografía Computarizada por Rayos X , Listas de EsperaRESUMEN
BACKGROUND AND PURPOSE: Sampling theory and operator characteristic curves are methods that can determine an optimal schedule for quality control tests. We apply this method to positional data for whole breast radiotherapy since several surveys report inconsistent image guidance practice for this technique. MATERIALS AND METHODS: Positional errors were defined, for 55 consecutive breast cancer patients, by comparing the central lung distance measured on portal images with that obtained from the corresponding digitally reconstructed radiograph. From the distribution of positional errors, the probability of a setup error >5 mm in the direction of the mediastinum was established. Using operator characteristic curves, we compared the effectiveness of various image-guidance schedules in dealing with such errors. We also calculated the dosimetric impact of undetected errors. RESULTS: Setup errors >5 mm towards the mediastinum for this cohort were unlikely, at 2.7%. Imaging half of the fractions protects most patients against three or more undetected errors. Undetected, such an error increases, on average, the maximum dose to 10 cm3 of the heart by 50 cGy, the mean heart dose by 4 cGy, and the left lung V20Gy by 0.2%; therefore, the clinical impact is minute. Given that detected positional errors outside of tolerance are corrected, their residual likelihood decreases with the ratio of fractions being imaged. CONCLUSIONS: For most tangential breast radiotherapy patients, setup errors >5 mm towards the mediastinum are unlikely, and their dosimetric impact is remote. Imaging half of the fractions of a course of whole breast radiotherapy prevents these errors to occur more than twice.
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Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/radioterapia , Control de Calidad , Radiometría/métodos , Errores de Configuración en Radioterapia/prevención & control , Algoritmos , Femenino , Humanos , Mediastino/efectos de la radiación , Errores Médicos/prevención & control , Posicionamiento del Paciente , Curva ROC , Dosis de Radiación , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia Guiada por Imagen/métodos , Reproducibilidad de los Resultados , Estudios RetrospectivosRESUMEN
PURPOSE: To compare intensity-modulated radiotherapy (IMRT) with conformal RT (CRT) for hypofractionated isotoxicity liver RT and explore dose escalation using IMRT for the same/improved nominal risk of liver toxicity in a treatment planning study. METHODS AND MATERIALS: A total of 26 CRT plans were evaluated. Prescription doses (24-54 Gy within six fractions) were individualized on the basis of the effective liver volume irradiated maintaining < or =5% risk of radiation-induced liver disease. The dose constraints included bowel (0.5 cm(3)) and stomach (0.5 cm(3)) to < or =30 Gy, spinal cord to < or =25 Gy, and planning target volume (PTV) to < or =140% of the prescribed dose. Two groups were evaluated: (1) PTV overlapping or directly adjacent to serial functioning normal tissues (n = 14), and (2) the liver as the dose-limiting normal tissue (n = 12). IMRT plans using direct machine parameter optimization maintained the CRT plan beam arrangements, an estimated radiation-induced liver disease risk of 5%, and underwent dose escalation, if all normal tissue constraints were maintained. RESULTS: IMRT improved PTV coverage in 19 of 26 plans (73%). Dose escalation was feasible in 9 cases by an average of 3.8 Gy (range, 0.6-13.2) in six fractions. Three of seven plans without improved PTV coverage had small gross tumor volumes (< or =105 cm(3)) already receiving 54 Gy, the maximal prescription dose allowed. In the remaining cases, the PTV range was 9.6-689 cm(3); two had overlapped organs at risk; and one had four targets. IMRT did not improve these plans owing to poor target coverage (n = 2) and nonliver (n = 2) dose limits. CONCLUSION: Direct machine parameter optimization IMRT improved PTV coverage while maintaining normal tissue tolerances in most CRT liver plans. Dose escalation was possible in a minority of patients.
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Carcinoma Hepatocelular/radioterapia , Neoplasias Hepáticas/radioterapia , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia Conformacional/métodos , Radioterapia de Intensidad Modulada/métodos , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Hepatocelular/diagnóstico por imagen , Fraccionamiento de la Dosis de Radiación , Femenino , Humanos , Intestinos/efectos de la radiación , Hígado/efectos de la radiación , Neoplasias Hepáticas/diagnóstico por imagen , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Tolerancia a Radiación , Radiografía , Médula Espinal/efectos de la radiación , Estómago/efectos de la radiación , Carga TumoralRESUMEN
The introduction of volumetric X-ray image-guided radiotherapy systems allows improved management of geometric variations in patient setup and internal organ motion. As these systems become a routine clinical modality, we propose a daily quality assurance (QA) program for cone-beam computed tomography (CBCT) integrated with a linear accelerator. The image-guided system used in this work combines a linear accelerator with conventional X-ray tube and an amorphous silicon flat-panel detector mounted orthogonally from the accelerator central beam axis. This article focuses on daily QA protocols germane to geometric accuracy of the CBCT systems and proposes tolerance levels on the basis of more than 3 years of experience with seven CBCT systems used in our clinic. Monthly geometric calibration tests demonstrate the long-term stability of the flex movements, which are reproducible within +/-0.5 mm (95% confidence interval). The daily QA procedure demonstrates that, for rigid phantoms, the accuracy of the image-guided process can be within 1 mm on average, with a 99% confidence interval of +/-2 mm.
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Tomografía Computarizada de Haz Cónico/normas , Aceleradores de Partículas , Radioterapia Asistida por Computador/normas , Calibración , Tomografía Computarizada de Haz Cónico/instrumentación , Tomografía Computarizada de Haz Cónico/métodos , Movimiento , Radioterapia Asistida por Computador/instrumentación , Radioterapia Asistida por Computador/métodos , Integración de SistemasRESUMEN
The clinical introduction of volumetric x-ray image-guided radiotherapy systems necessitates formal commissioning of the hardware and image-guided processes to be used and drafts quality assurance (QA) for both hardware and processes. Satisfying both requirements provides confidence on the system's ability to manage geometric variations in patient setup and internal organ motion. As these systems become a routine clinical modality, the authors present data from their QA program tracking the image quality performance of ten volumetric systems over a period of 3 years. These data are subsequently used to establish evidence-based tolerances for a QA program. The volumetric imaging systems used in this work combines a linear accelerator with conventional x-ray tube and an amorphous silicon flat-panel detector mounted orthogonally from the accelerator central beam axis, in a cone-beam computed tomography (CBCT) configuration. In the spirit of the AAPM Report No. 74, the present work presents the image quality portion of their QA program; the aspects of the QA protocol addressing imaging geometry have been presented elsewhere. Specifically, the authors are presenting data demonstrating the high linearity of CT numbers, the uniformity of axial reconstructions, and the high contrast spatial resolution of ten CBCT systems (1-2 mm) from two commercial vendors. They are also presenting data accumulated over the period of several months demonstrating the long-term stability of the flat-panel detector and of the distances measured on reconstructed volumetric images. Their tests demonstrate that each specific CBCT system has unique performance. In addition, scattered x rays are shown to influence the imaging performance in terms of spatial resolution, axial reconstruction uniformity, and the linearity of CT numbers.
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Tomografía Computarizada de Haz Cónico/instrumentación , Tomografía Computarizada de Haz Cónico/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Algoritmos , Calibración , Computadores , Diseño de Equipo , Humanos , Procesamiento de Imagen Asistido por Computador , Aceleradores de Partículas , Fantasmas de Imagen , Control de Calidad , Reproducibilidad de los Resultados , Programas Informáticos , Factores de Tiempo , Rayos XRESUMEN
PURPOSE: To describe the incidence and type of brachytherapy patient safety events over 10 years in an academic brachytherapy program. METHODS AND MATERIALS: Brachytherapy patient safety events reported between January 2007 and August 2016 were retrieved from the incident reporting system and reclassified using the recently developed National System for Incident Reporting in Radiation Treatment taxonomy. A multi-incident analysis was conducted to identify common themes and key learning points. RESULTS: During the study period, 3095 patients received 4967 brachytherapy fractions. An additional 179 patients had MR-guided prostate biopsies without treatment as part of an interventional research program. A total of 94 brachytherapy- or biopsy-related safety events (incidents, near misses, or programmatic hazards) were identified, corresponding to a rate of 2.8% of brachytherapy patients, 1.7% of brachytherapy fractions, and 3.4% of patients undergoing MR-guided prostate biopsy. Fifty-one (54%) events were classified as actual incidents, 29 (31%) as near misses, and 14 (15%) as programmatic hazards. Two events were associated with moderate acute medical harm or dosimetric severity, and two were associated with high dosimetric severity. Multi-incident analysis identified five high-risk activities or clinical scenarios as follows: (1) uncommon, low-volume or newly implemented brachytherapy procedures, (2) real-time MR-guided brachytherapy or biopsy procedures, (3) use of in-house devices or software, (4) manual data entry, and (5) patient scheduling and handoffs. CONCLUSIONS: Brachytherapy is a safe treatment and associated with a low rate of patient safety events. Effective incident management is a key element of continuous quality improvement and patient safety in brachytherapy.
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Braquiterapia/efectos adversos , Potencial Evento Adverso/estadística & datos numéricos , Seguridad del Paciente , Evaluación de Procesos, Atención de Salud , Próstata/patología , Centros Médicos Académicos/estadística & datos numéricos , Braquiterapia/métodos , Braquiterapia/normas , Humanos , Biopsia Guiada por Imagen/efectos adversos , Imagen por Resonancia Magnética , Masculino , Próstata/diagnóstico por imagen , Mejoramiento de la Calidad , Dosificación Radioterapéutica , Gestión de RiesgosRESUMEN
BACKGROUND AND PURPOSE: A FDG-PET/CT image feature with optimal prognostic potential for locally-advanced non-small cell lung cancer (LA-NSCLC) patients has yet to be identified, and neither has the optimal time for FDG-PET/CT response assessment; furthermore, nodal features have been largely ignored in the literature. We propose to identify image features or imaging time point with maximal prognostic power. MATERIALS AND METHODS: Consecutive consenting patients with LA-NSCLC receiving curative intent CRT were enrolled. 4DPET/4DCT scans were acquired 0, 2, 4, and 7â¯weeks during IMRT treatment. Eleven image features and their rates of change were recorded for each time point and tested for each of the possible outcome 2â¯years post CRT using the Kaplan-Meier method. RESULTS: 32 consecutive patients were recruited, 27 completing all scans. Restricting analysis to 4DPET/4DCT features and rates of change with pâ¯<â¯0.005, several volume-based features and their rates of change reached significance. Image features involving nodal disease were the only ones associated with overall survival. CONCLUSIONS: Several 4DPET/CT features and rates of change can reach significant association (pâ¯<â¯0.005) with outcomes, including overall survival, at many time points. The optimal time for adaptive CRT is therefore not constrained uniquely on imaging.
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Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/terapia , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/terapia , Planificación de la Radioterapia Asistida por Computador/métodos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Quimioradioterapia , Tomografía Computarizada Cuatridimensional/métodos , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/radioterapia , Tomografía Computarizada por Tomografía de Emisión de Positrones , PronósticoRESUMEN
We explain the rationale for metabolically adaptive radiation dose escalation in stage III non-small-cell lung cancer and describe the design of a Canadian phase II randomized trial investigating this approach. In the trial, patients are randomized to either conventional chemoradiation treatment (60 Gy in 30 fractions) or metabolically adaptive chemoradiation, where fluorodeoxyglucose-avid tumor sub-volumes receive an integrated boost dose to a maximum of 85 Gy in 30 fractions. The trial sample size is 78 patients, and the target population is patients with newly diagnosed, inoperable stage III non-small-cell lung cancer treated with radical intent chemoradiation. The primary objective of the trial is to determine if dose escalation to metabolically active sub-volumes will reduce 2-year local-regional failure rate from 42.3% to 22.3%, when compared with standard treatment. The secondary objectives are to determine the effect of dose escalation on overall survival, progression-free survival, quality of life, and rate of grade 3 to 5 toxicities.