The aim of this study was to analyze the influence of filters (algorithms) to improve the image of Cone Beam Computed Tomography (CBCT) in diagnosis of osteolytic lesions of the mandible, in order to establish the protocols for viewing images more suitable for CBCT diagnostics. 15 dry mandibles in which perforations were performed, simulating lesions, were submitted to CBCT examination. Two examiners analyzed the images, using filters to improve image Hard, Normal, and Very Sharp, contained in the iCAT Vision software, and protocols for assessment: axial; sagittal and coronal; and axial, sagittal and coronal planes simultaneously (MPR), on two occasions. The sensitivity and specificity (validity) of the cone beam computed tomography (CBCT) have been demonstrated as the values achieved were above 75% for sensitivity and above 85% for specificity, reaching around 95.5% of sensitivity and 99% of specificity when we used the appropriate observation protocol. It was concluded that the use of filters (algorithms) to improve the CBCT image influences the diagnosis, due to the fact that all measured values were correspondingly higher when it was used the filter Very Sharp, which justifies its use for clinical activities, followed by Hard and Normal filters, in order of decreasing values.

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Objetivo: Analisar os achados tomográficos fortuitos em seios maxilares por meio de exames de Tomografia Computadorizada por Feixe Cônico, bem como sua correlação com a sintomatologia clínica relatada. Método: Exames da maxila de 54 pacientes foram avaliados por dois examinadores independentes considerando os seios maxilares direito e esquerdo (n=108). Foi verificada a ocorrência de patologias sinusais nas paredes anterior, medial, lateral e posterior, assoalho e teto dos seios maxilares, utilizando o software i-CAT Vision ® (versão 1.6.20). Esses dados foram correlacionados com a presença ou ausência de sintomatologia relacionada à patologia sinusal. Resultados: O achado tomográfico mais observado foi a opacificação do seio pelo acúmulo de secreções (28,70%), seguido pelo espessamento da mucosa antral do seio maxilar (20,37%) e pela presença de cisto mucoso (17,59%). Em 60,22% dos casos não houve relato de sintomatologia clínica, independente da presença de patologias. A ocorrência de sintomatologia e achados tomográficos concomitantemente foi observada em 35,20% dos seios examinados, enquanto em 45,37% o achado tomográfico estava presente, sem, contanto, haver relato de sintomatologia. As paredes dos seios mais afetadas foram o assoalho (71,30%), correlacionando fator odontogênico associado, e a parede medial (57,40%), estando relacionada à frequência de infecções das vias aéreas superiores. O protocolo de visualização multiplanar obteve total acurácia e sensibilidade (100%), seguido pelos protocolos coronal (81,50%), e axial (76%). Conclusão: O exame de Tomografia Computadorizada por Feixe Cônico mostrou-se útil para definir a presença de patologias sinusais, porém é inespecífico na correlação dos achados em pacientes sintomáticos e na intensidade destes sintomas.Tomografia computadorizada por raios X; Seio maxilar; Tomografia computadorizada de feixe cônico.Objective: To analyze the eventual tomographic findings in maxillary sinuses by cone beam computed tomography as well as its relationship with the reported clinical symptoms. Method: Maxillary exams of 54 patients were evaluated by two independent examiners considering the right and left maxillary sinuses (n=108). There were sinus pathologies on the anterior, medial, lateral and posterior walls, the floor and ceiling of maxillary sinuses, detected with the i-CAT Vision ® (version 1.6.20) software. The collected data were correlated with the presence or absence of symptoms related to the sinus pathology. Results: The most frequent tomographic finding was opacification of the sinuses by accumulation of sinusoidal secretions (28.70%), followed by thickening of the antral mucosa of the maxillary sinus (20.37%) and the presence of mucous cyst (17.59%). In 60.22% of the cases, there was no report of clinical symptomatology regardless of the presence of pathology. Simultaneous presence of symptoms and tomographic findings occurred in 35.20% of the sinuses, while in 45.37% there was a tomographic finding without reported symptomatology. The most affected sinus wa...

During a transcatheter aortic valve implantation, an axisymmetric implant is placed in an irregularly shaped aortic root. Implanting an incorrect size can cause complications such as leakage of blood alongside or through the implant. The aim of this study was to construct a method that determines the optimal size of the implant based on the 3-dimensional shape of the aortic root. Based on the pre-interventional computed tomography scan of 89 patients, a statistical shape model (SSM) of their aortic root was constructed. The weights associated with the principal components of the SSM served as a parametric description of each aortic root. These weights and the volume of calcification in the aortic valve were used as parameters in a generalized linear model and a random forest classifier. Both classification algorithms were trained using the patients with no or mild leakage after their intervention. Subsequently, the algorithms were applied to the patients with moderate to severe leakage. The random forest classifier was accurate in 96% of the training cases. 55% of the patients with moderate to severe leakage were assigned a different size implant, 11 out of those 20 got one size smaller. The proposed method was capable of accurately and semi-automatically determining an implant size, using a CT scan of the aortic root. Further research is required to assess whether the different size implants would improve the outcome of those patients.