Search results for "Planned Dose"
showing 6 items of 6 documents
9 Development of an experimental tool to evaluate normal tissue 3D doses in external-beam radiotherapy
2018
Introduction Recently, cancer treatment improvement enabled an increase in patients’ survival rate. In more than half of the cases, radiotherapy participates in the cure for cancer. The efficacy of this technique is well known but it inevitably delivers doses to normal tissues exposing them to radio-induced complications risks [1] . Moreover, the longer patients’ life expectancy increases the risk of developing long-term complications such as second cancers. Thus, evaluating the risks following cancer treatment involving radiotherapy constitutes a major challenge. In this context, an experimental tool has been developed to evaluate normal tissue doses delivered by the different radiotherapy…
Mapping of failures after radiochemotherapy in patients with non-metastatic esophageal cancer: A posteriori analysis of the dose distribution in the …
2015
Abstract Background and purpose We aimed to evaluate the patterns of loco-regional failure (LRF) after exclusive chemoradiotherapy (eCRT) for esophageal cancer with respect to planned dose and/or the incidental (unplanned) dose outside target volumes. Materials and methods Co-image registration of CT or 18 F-FDG PET-CT at the time of failure (tf) and at the time of CRT (t0) was performed in 34 patients with LRF. Dosimetric parameters with regard to local failure (LF), nodal failure (NF) and involved nodal stations (NS) were derived. Results Twenty-two patients (64.7%) had LF, the majority of which (95.5%) were located at the epicenter of the GTV of the primary tumor. The mean doses recalcul…
Dose–volume-related dysphagia after constrictor muscles definition in head and neck cancer intensity-modulated radiation treatment
2014
Dysphagia remains a side effect influencing the quality of life of patients with head and neck cancer (HNC) after radiotherapy. We evaluated the relationship between planned dose involvement and acute and late dysphagia in patients with HNC treated with intensity-modulated radiation therapy (IMRT), after a recontouring of constrictor muscles (PCs) and the cricopharyngeal muscle (CM).Between December 2011 and December 2013, 56 patients with histologically proven HNC were treated with IMRT or volumetric-modulated arc therapy. The PCs and CM were recontoured. Correlations between acute and late toxicity and dosimetric parameters were evaluated. End points were analysed using univariate logisti…
EPR/alanine dosimetry for two therapeutic proton beams
2016
Abstract In this work the analysis of the electron paramagnetic resonance (EPR) response of alanine pellets exposed to two different clinical proton beams employed for radiotherapy is performed. One beam is characterized by a passive delivery technique and is dedicated to the eyes treatment (OPTIS2 beam line). Alanine pellets were irradiated with a 70 MeV proton beam corresponding to 35 mm range in eye tissue. We investigated how collimators with different sizes and shape used to conform the dose to the planned target volume influence the delivered dose. For this purpose we performed measurements with varying the collimator size (Output Factor) and the results were compared with those obtai…
An approach to using conventional brachytherapy software for clinical treatment planning of complex, Monte Carlo-based brachytherapy dose distributio…
2009
Certain brachytherapy dose distributions, such as those for LDR prostate implants, are readily modeled by treatment planning systems (TPS) that use the superposition principle of individual seed dose distributions to calculate the total dose distribution. However, dose distributions for brachytherapy treatments using high-Z shields or having significant material heterogeneities are not currently well modeled using conventional TPS. The purpose of this study is to establish a new treatment planning technique (Tufts technique) that could be applied in some clinical situations where the conventional approach is not acceptable and dose distributions present cylindrical symmetry. Dose distributi…
MO-D-AUD B-08: Treatment Planning for Complex Brachytherapy Dose Distributions Using High-Z Shields and Conventional Software
2008
Purpose: Certain brachytherapydose distributions, like for LDR prostate implants, are readily modeled by treatment planningsoftware using the superposition principle of individual seeds to replicate the total dose distribution. However, dose distributions for brachytherapy treatments using high‐Z shields are currently not well‐modeled using conventional software.Method and Materials:Dose distributions from complex brachytherapy plaques determined using Monte Carlo methods were used as input data, and included COMS‐based eye plaques using 125 I , 103 Pd , and 131 Cs ; 4–8cm diameter AccuBoost peripheral breast brachytherapy applicators from Advanced Radiation Therapy; and the 2 and 3cm diame…