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Radiotherapy is a recommended procedure, in average, for 52% of cancer cases as one of the treatment forms, therefore, it is important for the clinical practice to investigate the affecting factors in dose distribution received by the patients, and for example, devices and treatment couch. With the introduction of treatments with modulated intensity techniques like IMRT and VMAT, the number of incidence fields used for patient treatment increased, which makes the couch’s dosimetric effect more significant in these modalities. The attenuation data acquisition referring to the treatment couches, as well as the TPS data evaluation, show as important parameters for the clinical practice because they show what happens with the dose delivery during the treatment, ensuring a better quality and safety to the treatments. This research presents experimental results evaluating the couch’s impact in the treatments by a study of perturbation in the distribution of surface dose, dose attenuation according to the gantry’s angle for the couches BrainLABTM, ExactTM and iBEAMTM. Then we propose better density values for the couches BrainLABTM and ExactTM for their inclusion in EclipseTM TPS. Lastly, we compare the dose difference considering the presence or not of couch in the planning. In conclusion, the beam’s attenuation increase by the couches and the doses alterations on the skin must be taken in consideration in the treatment planning process. It is of great relevance that each treatment center perform internal tests to determinate the best density values for available TPS.

The formalism used for barriers calculations is based on a conservative estimation of workload, use factor, and occupancy factor. IMRT techniques (Intensity Modulated Radiation Therapy) and VMAT (Volumetric Modulated Arc Therapy) are known for being superior to conventional techniques, but costly from the shielding standpoint, as they increase the number of monitor units used to deliver the same dose to the patient, increasing the leakage radiation produced and, consequently, the thickness of the secondary barriers. At InRad (Radiology Institute of HC-FMUSP) a 2100CD LINAC already installed was upgraded to perform IMRT/VMAT techniques, and the existing barrier was reassessed. The present study proposes a methodology for acquiring real workload data from the institution's management software (MOSAIQ®) to replace the initially estimated data and recalculate the thickness of the barriers, assessing the impact of the introduction of these techniques and understanding the profile of the treatments carried out at the institution over the years of 2010 to 2020. Through this methodology, a decrease in the workload of 15 MV was observed as the technique of modulated intensity with 6 MV was introduced, reducing the thicknesses calculated for primary barriers. However, no significant changes were observed in the thicknesses calculated for the secondary barriers, because despite the increase in the leakage workload of 6 MV, the total workload of 15 MV decreased. There was also a trend towards an increase in the number of patients treated with modulated intensity year after year, which went from 5% in 2016 to 67% in 2020.

Este artigo dedica-se, com base em fragmentos de um caso clínico, a discutir a contribuição dos traços mnêmicos filo e ontogenéticos para a formação de compromissos que acontecem diante do terror suscitado pela velhice. Concomitantemente, apresenta a viabilidade do amparo clínico como alternativa à ameaça de desamparo que emerge da consciência de finitude e salienta a complexidade e a importância do trabalho psíquico de envelhescência como condição fundamental à escuta na transferência.

Based on fragments of a clinical case, this paper discusses the contribution of phylo and ontogenetic mnemonic traits to the formation of commitments that occur facing the terror of old age. At the same time, it presents the feasibility of clinical support as an alternative to the threat of abandonment that emerges from consciousness of finitude, and highlights the complexity and the importance of psychological work referring to aging as a fundamental condition to listening in transference. [ABSTRACT FROM AUTHOR]

Based on fragments of a clinical case, this paper discusses the contribution of phylo and ontogenetic mnemonic traits to the formation of commitments that occur facing the terror of old age. At the same time, it presents the feasibility of clinical support as an alternative to the threat of abandonment that emerges from consciousness of finitude, and highlights the complexity and the importance of psychological work referring to aging as a fundamental condition to listening in transference. [ABSTRACT FROM AUTHOR]