RESUMO
OBJECTIVES: To present and execute a protocol for the capture of 3D facial images using photogrammetry through the open access software Blender and its add-on OrtogOnBlender (OOB) and to evaluate the compatibility of the 3D meshes generated with Computed tomography (CT) of the sinuses. METHODS: Individuals >18 years old, candidates for Rhinoseptoplasty in a tertiary hospital, were submitted to a photographic session to perform the standardized protocol. In the session, divided into 3 phases, sequential photos were taken for processing the photogrammetry in the OOB and producing 3D meshes of the face. The photogrammetry reconstructions were compared with the reference mesh of the soft tissue surface of the Sinus CT scan to assess compatibility between them. RESULTS: 21 patients were included, 67% female. 3 photogrammetry meshes and 1 CT reference mesh were generated, which demonstrated matching compatibility, as most of the mean distances between cloud points were <1.48â¯mm. Phase 3 of the session with the highest number of photos (54.36⯱â¯15.05) generated the most satisfactory mesh with the best resolution. CONCLUSIONS: The proposed protocol is reproducible and feasible in clinical practice, generated satisfactory 3D meshes of the face, being a potential tool for surgical planning and comparison of results. For the implementation of photogrammetry for use in 3D anthropometry, it is necessary to validate this method. LEVEL OF EVIDENCE: 3: OCEBM Levels of Evidence Working Group.1 "The Oxford 2011 Levels of Evidence". Oxford Centre for Evidence-Based Medicine. http://www.cebm.net/index.aspx?o=5653.
Assuntos
Face , Imageamento Tridimensional , Feminino , Humanos , Masculino , Antropometria , Face/diagnóstico por imagem , Face/cirurgia , Face/anatomia & histologia , Imageamento Tridimensional/métodos , Fotogrametria/métodos , Software , AdultoRESUMO
OBJECTIVE: To validate the use of a three-dimensional printing system for metric and volumetric analysis of the segments of an abdominal aortic aneurysm (AAA). MATERIALS AND METHODS: In patients scheduled to undergo endovascular AAA repair, the computed tomography angiography (CTA) measurements obtained during the preoperative assessment of the patients were compared with those obtained by computed tomography of individualized three-dimensional biomodels. RESULTS: The volumetric assessment showed a discrepancy of 3-12%, and the difference between the areas was 10-16%. CONCLUSION: Computed tomography measurements of 3D-printed biomodels of AAAs appear to be comparable to those of threedimensional CTA measurements of the same AAAs, in terms of the metric and volumetric dimensions.
OBJETIVO: Validar a aplicação do método de impressão tridimensional de biomodelos para aferição métrica e volumétrica de segmentos de aneurisma de aorta abdominal. MATERIAIS E MÉTODOS: Compararam-se as medidas obtidas por tomografia computadorizada dos biomodelos tridimensionais com as realizadas no planejamento pré-operatório de pacientes submetidos a correção endovascular de aneurisma de aorta abdominal. RESULTADOS: A avaliação da volumetria demonstrou discrepância de 3% a 12% e a diferença entre as áreas foi de 10% a 16%. CONCLUSÃO: A tomografia computadorizada dos biomodelos impressos é compatível nas aferições métricas e volumétricas com as imagens tridimensionais da angiotomografia do paciente.
RESUMO
During the acquisition on a low-dose radiation computed tomography (CT) scan, images are usually marked by heavy noise and undesired artifacts, which dramatically reduce its applicability in the image processing workflow. A noise reduction and detail preservation filter based on mathematical morphology is presented in this paper. The filter is geared to allow control of an opening operator followed by a systematic contrast limited adaptive histogram equalization (CLAHE) in conjunction with a reconstruction by dilation in last stage. A quantitative metric built on peak signal-to-noise ratio (PSNR), structural similarity (SSIM), and mean-squared error (MSE) were applied to check noise reduction, detail preservation, and performance. The results obtained by the proposed filter were compared with those obtained in the literature, showing very good results: compared with the best-tested filter, the filter had a gain of 7.91% on PSNR, 7.57% on SSIM and 37.8% on MSE.