13 documents found, page 1 of 2
Avaliação das doses de Cone Beam Computed Tomography (CBCT) em pediatria
Cravo Sá , Ana; Campos, Guilherme; Fernandes, Paulo; Di Maria , SalvatoreEnquadramento: O CBCT é o tipo de imagem mais utilizado em radioterapia, no entanto não existem recomendações para os diferentes protocolos [1]. As doses provenientes das imagens diárias poderão atingir 1-3% da dose prescrita, aumentando o risco de tumores radio-induzidos, sendo importante aferir para doentes pediátricos [2]. Objetivo: Pretende-se avaliar as doses de CBCT em doentes pediátricos. Métodos: As med...
Estudo experimental das doses por Tomografia Computorizada de Feixe Cónico em r...
Anastácio Bonito , André Filipe; Cravo Sá, Ana; Ribeiro, Filipa; Campos, Guilherme; Moreno , Lília; Jesus Costa , Maria; Pontes , MiguelEnquadramento: A Tomografia Computorizada por Feixe Cónico (TCFC) é usada para verificação dos tratamentos em radioterapia (RT). Contudo, a sua utilização implica uma dose adicional de radiação para o doente o que poderá potenciar preocupações sobre os efeitos tecidulares a longo prazo [1-4]. Objetivos: Pretende-se, avaliar as doses absorvidas por TCFC nos protocolos de cabeça, tórax e pélvico e entre três inst...
Robotic radiosurgery for temporal bone paragangliomas: single-center experience...
Ramos, Sofia; Simões , Sara; Amorim, Marina; Costa, Maria Adelina; Campos, Guilherme; Fonseca, Graça; Carvalho, Miguel; Vieira, Pedro; Calçada, CármenObjective: To report the experience of a single center in the treatment of temporal bone paragangliomas with Robotic Radiosurgery. Study Design: Single-center retrospective analysis Material and Methods: Between 2017 and 2021, 8 patients with temporal bone paragangliomas were treated with Cyberknife in the Department of Radiation Oncology of Instituto CUF Porto. Results: Half of the patients were diagnosed with...
Dose assessment in paediatric CBCT using measurements, MC simulations and image...
Sá, Ana Cravo; Campos, Guilherme; Pontes, Miguel; Fernandes, Paulo; Di Maria, SalvatoreCurrently in radiotherapy, Image-Guided Radiation Therapy (IGRT) is a cornerstone for achieving submillimeter treatment precision. Cone Beam Computed Tomography (CBCT) is the type of IGRT most commonly used in radiotherapy departments. However, there are no guidelines for the different types of protocols and image parameters used, which leads to different absorbed doses in healthy tissues and this is especially...
Making clinical simulation mannequins talk
Cossa, Isac; Campos, Guilherme; Couto, Pedro; Lindo, JoãoThis paper advocates the interest of applying speech synthesis to clinical simulation mannequins, by focussing on a particular case study of recognised practical interest (evaluation of consciousness level based on the Glasgow Coma Scale), chosen as a proof of concept. A response repository comprising 109 sentences was recorded and an application was developed in Microsoft® Visual Basic® to allow configuration ...
Learning auditory space: generalization and long-term effects
Mendonça, Catarina; Campos, Guilherme; Dias, Paulo; Santos, Jorge A.Background: Previous findings have shown that humans can learn to localize with altered auditory space cues. Here we analyze such learning processes and their effects up to one month on both localization accuracy and sound externalization. Subjects were trained and retested, focusing on the effects of stimulus type in learning, stimulus type in localization, stimulus position, previous experience, externalizati...
Learning Auditory Space: Generalization and Long-Term Effects
Mendonça, Catarina; Campos, Guilherme; Dias, Paulo; Santos, JorgeBackground: Previous findings have shown that humans can learn to localize with altered auditory space cues. Here we analyze such learning processes and their effects up to one month on both localization accuracy and sound externalization. Subjects were trained and retested, focusing on the effects of stimulus type in learning, stimulus type in localization, stimulus position, previous experience, externalizati...
Real-time auralisation system for virtual microphone positioning
Barker, Tom; Campos, Guilherme; Dias, Paulo; Vieira, José; Mendonça, Catarina; Santos, Jorge A.A computer application was developed to simulate the process of microphone positioning in sound recording applications. A dense, regular grid of impulse responses pre-recorded on the region of the room under study allowed the sound captured by a virtual mi- crophone to be auralised through real-time convolution with an anechoic stream representing the sound source. Convolution was performed using a block-based ...
On the improvement of localization accuracy with nonindividualized HRTF-based s...
Mendonça, Catarina; Campos, Guilherme; Dias, Paulo; Vieira, José; Ferreira, João P.; Santos, Jorge A.Auralization is a powerful tool to increase the realism and sense of immersion in Virtual Reality environments. The Head Related Transfer Function (HRTF) filters commonly used for auralization are non-individualized, as obtaining individualized HRTFs poses very serious practical difficulties. It is therefore extremely important to understand to what extent this hinders sound perception. In this paper, we addres...
On the adaptation to non-individualized HRTF auralisations: A longitudinal study
Mendonça, Catarina; Santos, Jorge A.; Campos, Guilherme; Dias, Paulo Miguel de Jesus; Vieira, JoséAuralisations with HRTFs are an innovative tool for the reproduction of acoustic space. Their broad applicability depends on the use of non-individualised models, but little is known on how humans adapt to these sounds. Previous findings have shown that simple exposure to non-individualised virtual sounds did not provide a quick adaptation, but that training and feedback would boost this process. Here, we were ...