Percorrer por autor "Belinha, Jorge"
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- Computational model to predict the temperature distribution produced by bone cementPublication . Oliveira, Vânia C.C.; Fonseca, E.M.M.; Oliveira, A.F.; Belinha, Jorge; Rua, Cláudia C.; Piloto, P.A.G.; Jorge, Renato N.Bone is the third frequent location for haematogenous dissemination of malignant tumors. Patients with multiple bone metastases are exponentially growing. Bone metastases, which are frequently diagnosed late, are associated to imminent and pathological bone fractures. Metastatic disease translates an advanced tumor stage and it has a high impact in patients’ quality of life and survival. The main objective is to study the thermal effect induced by the bone cement polymerization, in the bone metastatic tumor reduction and to understand the role of such procedure and its biomechanical stabilization. To assess the clinical effect, it is important to test this methodology before its application and obtain sustained results. In this work, a computational model was developed to predict the temperature distribution produced by cement polymerization, and verify the reduction of the metastatic tumor area due the thermal effect. Different simulations produced to evaluate the necrosis effect for two cement amount sizes introduced in a cortical and spongy bone tumor. The same computational models were reproduced introducing an endomedular nail in titanium and a femoral stem in cobalt-chrome material in pathological bone fractures.
- Effect of two different bone cements in thermal necrosis when associated to titanium versus carbon nailing for bone metastases a numerical studyPublication . Rua, Cláudia C.; Belinha, Jorge; Piloto, P.A.G.; Jorge, R.M. Natal; Oliveira, Vânia C.; Fonseca, E.M.M.The main objective of the paper is to study the thermal effect induced by different bone cements associated with intramedullary nails, titanium and carbon, in bone metastases treatment. The thermal necrosis effect of each cement polymerisation was verified to understand the role of such procedures. Numerical models with nailing systems, introduced in a cortical and spongy bone metastasis, were developed aiming to predict the temperature produced by different types and amount of cement polymerisation. The results showed that the polymerisation heat release in all models with a cement mantle filling in around the intramedullary nail and the necrosis largest area was predicted with CMW3®. It was verified that CF/PEEK nail and high viscosity Palacos R® reduce the heat transfer and the necrosis affected area. This effect could be an advantage for treatment, which aims to keep long-term stability and local metastatic disease control for functional improvement and pain relief.
- Estudo térmico numérico em sarcomas ósseosPublication . Rua, Cláudia C.; Oliveira, Vânia C.C.; Piloto, P.A.G.; Fonseca, E.M.M.; Belinha, Jorge; Jorge, Renato N.; Vasconcelos, José C.Com a evolução da ciência e das novas tecnologias de diagnóstico, foi possível observar uma melhoria contínua nos tratamentos em geral e no auxílio da qualidade de vida dos doentes. Os tumores podem ser benignos, podendo verificar-se um crescimento anormal de células sem capacidade de invadir outros tipos de tecidos e órgãos (metástase) ou malignos, em que as células crescem mais rápido e invadem outros tecidos. Podem ainda ser primários ou metastáticos, devido à disseminação de células cancerígenas sistémicas.
- Estudo térmico numérico em sarcomas ósseosPublication . Rua, Cláudia C.; Oliveira, Vânia C.C.; Piloto, P.A.G.; Fonseca, E.M.M.; Belinha, Jorge; Jorge, Renato N.; Vasconcelos, José C.Os sarcomas são tumores heterogéneos que se formam no tecido ósseo, tecido conjuntivo, tecido cartilageneo, tecido muscular, tecido adiposo, nervos periféricos e vasos sanguíneos, geralmente nas extremidades. A cimentação é uma técnica utilizada por exemplo, em procedimentos percutâneos como vertebroplastia, cifoplastia, osteoplastia e sacroplastia. Os cimentos ósseos são biomateriais sintéticos compostos por um polímero (pó) e um componente líquido (monómero). A introdução de cimento ósseo no tecido tem como objetivo tratar ou prevenir fraturas patológicas vertebrais e extraespinhais, aliviar a dor em doentes com osteoporose e metástases, por exemplo.
- Numerical thermal study in bone tumor lesionPublication . Rua, Cláudia C.; Fonseca, E.M.M.; Piloto, P.A.G.; Oliveira, Vânia C.; Belinha, Jorge; Jorge, R. Natal; Vasconcelos, JoséWith the evolution of science and new diagnostic technologies, it was possible to observe a continuous improvement in the treatments in general and in the aid of the patients' quality of life. Malignant tumors can be primary or secondary (metastases), with abnormal growth of cells able to invade other types of tissues and organs through systemic dissemination. Sarcomas are rare primary malignancies formed from mesenchymal tissue and often located at the extremities. In this work, the main objective is to evaluate the minimization of the evolution of bone tumor lesion through the injection of bone cement, filling in the space of the lytic tumor lesion. This methodology allows to verify at the adjacent cement – bone tissue interface, an increase in temperature that can control the local growth of bone metastasis. Different computational models, obtained by medical image processing, will be carried out for two analyses (patient younger than 70 years and older than 70 years). The computational model allows a transient thermal analysis using the finite element method. The temperature results may determine the thermal necrosis effect in the bone tumor lesion. Results will be compared using three different bone cements
- The heat transfer modelling for bone metastatic lesion minimization using two different cement typesPublication . Oliveira, Vânia C.; Fonseca, E.M.M.; Belinha, Jorge; Rua, Cláudia C.; Piloto, P.A.G.; Jorge, RenatoBone tumors grow when cells divide without any control, forming a tissue mass. Bone tumors could be benign or malignant, and primary or metastatic due to systemic cancer cells dissemination. They destroy bone and lead to pathological fractures. The main objective of this work is to study the thermal effect induced by the bone cement polymerization, in the bone metastatic tumor minimization. To assess the clinical effect, it is important to test this methodology before its application and obtain sustained results. In this work, a numerical model was developed to predict the temperature distribution produced by cement polymerization. Thus, distinct tests were produced for different two cements types and amounts introduced in a cortical and spongy bone metastatic lesion, with or without an intramedullary titanium nail. The bone cement was introduced to fill in a metastatic lytic lesion area, which the main objective is playing a promising role for bone tumor necrosis due to thermal effects and biomechanical stabilization for function and pain relief.
- The heat transfer modelling for minimization of bone tumor lesion using the cement polymerization effectPublication . Oliveira, Vânia C.; Fonseca, E.M.M.; Belinha, Jorge; Rua, Cláudia C.; Piloto, P.A.G.; Jorge, Renato N.Bone metastases, which are frequently diagnosed late, translate an advanced tumor stage and have a high impact in patients’ quality of life and survival. After the diagnosis and tumor staging, it is important to characterize the bone tumor lesions with specific attention to identify the size, type (osteolytic, osteoblastic, mix), location, etc. in the involved bone [1]. Tumors can destroy the spongy and cortical bone and extend to soft tissues.
- Thermal computational model to predict thermal necrosis in bone sarcomasPublication . Rua, Cláudia C.; Oliveira, Vânia C.C.; Piloto, P.A.G.; Fonseca, E.M.M.; Belinha, Jorge; Jorge, Renato N.; Vasconcelos, José C.Bone and soft tissue sarcomas are heterogeneous tumors that form from bone tissue, connective tissue, cartilaginous tissue, muscle tissue, adipose tissue, peripheral nerves, and blood vessels, usually at its extremities. Cementoplasty is a technique used for example in percutaneous procedures such as vertebroplasty, kyphoplasty, osteoplasty and sacroplasty [1]. cements are synthetic biomaterials composed of a polymer (powder) and a liquid component (monomer), used very successfully in various medical applications.
- Thermal computational model to predict thermal necrosis in bone sarcomasPublication . Rua, Cláudia C.; Oliveira, Vânia C.C.; Piloto, P.A.G.; Fonseca, E.M.M.; Belinha, Jorge; Jorge, Renato N.; Vasconcelos, José C.Sarcomas are heterogeneous tumors that form frombonetissue, connective tissue, cartilaginous tissue,muscle tissue, adipose tissue, peripheral nerves, and blood vessels,usually atits extremities. These tumors occur at any age and in any region of the patient's body.