Improvement In Cranioplasty: Advanced Prosthesis Biomanufacturing

Additive manufacturing (AM) is a technology that enables the production of models and prosthesis directly from the 3D CAD model facilitating surgical procedures, implant quality and reducing risks. Furthermore, the additive manufacturing has been used to produce implants especially designed for a particular patient, with sizes, shapes and mechanical properties optimized, in many areas of medicine such as cranioplasty surgery. This work presents AM technologies applied to design and manufacture of a biomodel, in fact, an implant for the surgical reconstruction of a large cranial defect. A series of computed tomography data was obtained and software was used to extract the cranial geometry. The protocol presented was used for creation of anatomic biomodel of the bone defect for the surgical planning as well as to design and manufacture of the patient-specific implant, reducing duration of surgery besides improving the surgical accuracy due to preoperative planning of the anatomical details. (C) 2015 The Authors. Published by Elsevier B.V.492032082nd CIRP Conference on Biomanufacturing (CIRP-BioM)JUL 29-31, 2015Manchester, ENGLAN

Medical reverse engineering applications and methods

Understanding, controlling and manipulation of patient data as well as shape, geometry and structure of the biomedical objects are important for developing Biomedical Engineering (BME) applications. Medical Reverse Engineering (MRE) is aimed to use the Reverse Engineering (RE) technology to reconstruct 3D models of the anatomical structures and biomedical objects for design and manufacturing of medical products as well as BME research and development. This paper presents the state of the art applications and methods about MRE. Different concepts and methodologies are provided to understand fundamentally the MRE processes and workflow. The key MRE applications are presented, including personalised implants for bone reconstruction, dental implants and simulations, surgical tools, medical training, vision science and optometry, orthopedics, ergonomics, orthosis, prosthesis, and tissue engineering. The current challenges as well as the hardware and software for MRE application development and research are discussed

Stereolithographic biomodelling to create tangible hard copies of the ethmoidal labyrinth air cells based on the visible human project

Rapid prototyping (RP), or stereolithography, is a new clinical application area, which is used to obtain accurate three-dimensional physical replicas of complex anatomical structures. The aim of this study was to create tangible hard copies of the ethmoidal labyrinth air cells (ELACs) with stereolithographic biomodelling. The visible human dataset (VHD) was used as the input imaging data. The Surfdriver software package was applied to these images to reconstruct the ELACs as three-dimensional DXF (data exchange file) models. These models were post-processed in 3D-Doctor software for virtual reality modelling language (VRML) and STL (Standard Triangulation Language) formats. Stereolithographic replicas were manufactured in a rapid prototyping machine by using the STL format. The total number of ELACs was 21. The dimensions of the ELACs on the right and left sides were 52.91 x 13.00 x 28.68 mm and 53.79 x 12.42 x 28.55 mm, respectively. The total volume of the ELACs was 4771.1003 mm3. The mean ELAC distance was 27.29 mm from the nasion and 71.09 mm from the calotte topologically. In conclusion, the combination of Surfdriver and 3D-Doctor could be effectively used for manufacturing 3D solid models from serial sections of anatomical structures. Stereolithographic anatomical models provide an innovative and complementary tool for students, researchers, and surgeons to apprehend these anatomical structures tangibly. The outcomes of these attempts can provide benefits in terms of the visualization, perception, and interpretation of the structures in anatomy teaching and prior to surgical interventions. (Folia Morphol 2011; 70, 1: 33-40

Biomechanical Stress and Strain Analysis of Mandibular Human Region from Computed Tomography to Custom Implant Development

Currently computational tools are helping and improving the processes and testing procedures in several areas of knowledge. Computed tomography (CT) is a diagnostic tool already consolidated and now beginning to be used as a tool for something even more innovative, creating biomodels. Biomodels are anatomical physical copies of human organs and tissues that are used for diagnosis and surgical planning. The use of tomographic images in the creation of biomodels has been arousing great interest in the medical and bioengineering area. In addition to creating biomodels by computed tomography it is also possible, using this process, to create mathematical models to perform computer simulations and analyses of regions of interest. This paper discusses the creation of a biomodel of the skull-mandibular region of a patient from CT for study and evaluation of efforts in the area of the temporomandibular joint (TMJ) aiming at the design and development of a TMJ custom prosthesis. The evaluation of efforts in the TMJ region due to the forces of mastication was made using the finite element method and the results were corroborated by comparison with mandibular models studied in similar works

Using 3D-printed Patient-optimized Surgical Tools (3D POST) for Complex Hip and Knee Arthroplasty

Planning is a key step in all surgeries. Well-planned cases have better outcomes than the unplanned ones. The conventional planning used to be done on radiographs and other imaging. Three-dimensional (3D) printing using additive manufacturing process has taken this a step further. The process involves converting the radiographic digital formats into machine-printable format. The three-dimensional model is typically made of a plastic material that allows surgical simulation

The application of rapid prototyping in facial surgeries: a series of case studies

Aim: the aim of this paper is to report on the applicability of biomodels obtained from computerized tomography (CT) images throughthe technique of stereolithography (SLA) and three-dimensional printing (3DP), in the clinical case reports of patients who underwentsurgeries involving dentoskeletal deformity, oral pathology and oral and maxillofacial trauma. Methodology: clinical case 01 dealswith fractures in the orbital and zygomatic arch region that required reconstruction and correction of diplopia, by means of CTimages, using the technique of three-dimensional printing through SLA, generating a mirrored biomodel for surgical planning andthe making of customized prosthesis. In clinical case 02, by means of CT images, a biomodel utilizing the 3DP technique showed thetotal area invaded by invasive ameloblastoma, making it possible to plan the osteotomy with maximum preservation of the adjacenttissue and prior modeling of the plate. In clinical case 03, rapid prototyping technology (RP) was used to make customized prosthesisfor temporomandibular joint, with the goal of correcting a serious idiopathic pathology provoking the resorption of the right and leftcondyles. Discussion: complex cases require the team to have recourse to technology for the implementation of the procedures, inorder to offer excellent quality treatment to the patient, in addition to facilitating surgical planning and permitting the constructionof customized prostheses. Conclusion: the rapid prototyping for the acquisition of biomodels is an important auxiliary tool for thesurgical team

Hemodynamic study in a real intracranial aneurysm: an in vitro and in silico approach

Mestrado de dupla diplomação com o Centro Federal de Educação Tecnológica Celso Suckow da Fonseca - Cefet/RJIntracranial aneurysm (IA) is a cerebrovascular disease with high rates of mortality and morbidity when it ruptures. It is known that changes in the intra-aneurysmal hemodynamic load play a significant factor in the development and rupture of IA. However, these factors are not fully understood. In this sense, the main objective of this work is to study the hemodynamic behavior during the blood analogues flow inside an AI and to determine its influence on the evolution of this pathology. To this end, experimental and numerical studies were carried out, using a real AI model obtained using computerized angiography. In the experimental approach, it was necessary, in the initial phase, to develop and manufacture biomodels from medical images of real aneurysms. Two techniques were used to manufacture the biomodels: rapid prototyping and gravity casting. The materials used to obtain the biomodels were of low cost. After manufacture, the biomodels were compared to each other for their transparency and final structure and proved to be suitable for testing flow visualizations. Numerical studies were performed with the aid of the Ansys Fluent software, using computational fluid dynamics (CFD), using the finite volume method. Subsequently, flow tests were performed experimentally and numerically using flow rates calculated from the velocity curve of a patient's doppler test. The experimental and numerical tests, in steady-state, made it possible to visualize the three-dimensional behavior of the flow inside the aneurysm, identifying the vortex zones created throughout the cardiac cycle. Correlating the results obtained in the two analyzes, it was possible to identify that the areas of vortexes are characterized by low speed and with increasing the fluid flow, the vortexes are positioned closer to the wall. These characteristics are associated with the rupture of an intracranial aneurysm. There was also a good qualitative correlation between numerical and experimental results.O aneurisma intracraniano (AI) é uma patologia cerebrovascular com altas taxas de mortalidade e morbidade quando se rompe. Sabe-se que alterações na carga hemodinâmica intra-aneurismática exerce um fator significativo no desenvolvimento e ruptura de AI, porém, esses fatores não estão totalmente compreendidos. Nesse sentido, o objetivo principal deste trabalho é o de estudar o comportamento hemodinâmico durante o escoamento de fluidos análogos do sangue no interior de um AI e determinar a sua influência na evolução da patologia. Para tal, foram realizados estudos experimentais e numéricos, utilizando um modelo de AI real obtido por meio de uma angiografia computadorizada. Na abordagem experimental foi necessário, na fase inicial, desenvolver e fabricar biomodelos a partir de imagens médicas de um aneurisma real. No fabrico dos biomodelos foram utilizadas duas técnicas: a prototipagem rápida e o vazamento por gravidade. Os materiais utilizados para a obtenção dos biomodelos foram de baixo custo. Após a fabricação, os biomodelos foram comparados entre si quanto à sua transparência e estrutura final e verificou-se serem adequados para testes de visualizações do fluxo. Os estudos numéricos foram realizados com recurso ao software Ansys Fluent, utilizando a dinâmica dos fluidos computacional (CFD), através do método dos volumes finitos. Posteriormente, foram realizados testes de escoamento experimentais e numéricos, utilizando caudais determinados a partir da curva de velocidades do ensaio doppler de um paciente. Os testes experimentais e numéricos, em regime permanente, possibilitaram a visualização do comportamento tridimensional do fluxo no interior do aneurisma, identificando as zonas de vórtices criadas ao longo do ciclo cardíaco. Correlacionando os resultados obtidos nas duas análises, foi possível identificar que as áreas de vórtices são caracterizadas por uma baixa velocidade e com o aumento do caudal os vórtices posicionam-se mais próximos da parede. Essas características apresentadas estão associadas com a ruptura de aneurisma intracraniano. Verificou-se, também, uma boa correlação qualitativa entre os resultados numéricos e experimentais