ABSTRACT
OBJECTIVES: To identify a normal pattern of mandibular trabecular bone in children based on the fractal dimension (FD), and its possible correlation with pixel intensity (PI) values, to facilitate the early diagnosis of possible diseases and/or future bone alterations. MATERIALS AND METHODS: The 50 panoramic images were selected and divided into two groups, according to the children's age: 8-9 (Group 1; n = 25) and 6-7 (Group 2; n = 25). For FD and PI analyses, three regions of interest (ROIs) were selected, and their mean values were evaluated for each ROI, according to each group, using the t test for independent samples and the model of generalized estimation equations (GEE). Subsequently, these mean values were correlated by the Pearson test. RESULTS: Comparing the groups, FD and PI did not differ from each other for any of the measured regions (p > 0.00). It was observed that in the mandible branch (ROI1), FD and PI means were 1.26 ± 0.01 and 81.0 ± 2.50, respectively. In the mandible angle (ROI2), the means were 1.21 ± 0.02 (FD) and 72.8 ± 2.13 (PI); and in the mandible, cortical (ROI3) values of FD = 1.03 ± 0.01 and PI = 91.3 ± 1.75 were obtained. There was no correlation between FD and PI in any of the analyzed ROI (r < 0.285). The FD means of ROI1 and ROI2 did not differ from each other (p = 0.053), but both were different from ROI3 (p < 0.00). All PI values differed from each other (p < 0.00). CONCLUSION: The bone trabeculate pattern in 6-9-year-old children presented FD between 1.01 and 1.29. Besides that, there was no significant correlation between FD and PI.
Subject(s)
Cancellous Bone , Fractals , Humans , Child , Pilot Projects , Radiography, Panoramic/methods , Mandible/diagnostic imagingABSTRACT
PURPOSE: To establish an evaluation protocol for the identification and description of the variations in multiple myeloma (MM) lesions of the jaws, by means of cone-beam computed tomography (CBCT). MATERIALS AND METHODS: Tomography exams from 33 MM patients were evaluated in this retrospective observational study. The reconstructions were analyzed simultaneously, according to the established protocol, with the following description criteria: anatomic location, size, margins, inner aspect, relationship with adjacent structures, and presence or absence of a punched-out aspect. The exams were further subdivided into groups of patients using, or not bisphosphonates. RESULTS: There were osteolytic lesions in 100% of cases, most of which were extended to more than one anatomical region. Poorly defined margins were more frequent in the maxilla than in the mandible. Extensive bone resorption presenting multilocular areas was the most frequently observed aspect, being 86.2% for maxilla and 87.9% for mandible. In relation to bisphosphonates, patients who used the medication had more poorly defined bone margins and contortions (68.6%) than those who did not undergo drug therapy (31.4%). No well-defined lesions were observed (p = 0.34%). CONCLUSION: It was possible to establish a protocol for evaluation of MM lesions in CBCT images and to identify that when evaluated three-dimensional, lesions tend to be poorly defined and have no pattern of description, as described in two-dimensional "punched-out".
Subject(s)
Multiple Myeloma , Cone-Beam Computed Tomography , Humans , Mandible/diagnostic imaging , Maxilla , Multiple Myeloma/diagnostic imaging , Retrospective StudiesABSTRACT
O mieloma múltiplo se desenvolve a partir de células neoplásicas de plasmócitos, causando um desequilíbrio na reabsorção e formação óssea, resultando no surgimento de lesões osteolíticas, as quais apresentam uma diversidade de aspectos imaginológicos. O objetivo neste estudo foi estabelecer um protocolo de avaliação por meio de tomografia computadorizada de feixe cônico, para a identificação e descrição das variações imaginológicas destas lesões, baseado em critérios padronizados. Um total de 33 exames de pacientes portadores de mieloma múltiplo foi avaliado, sendo subdivididos em dois grupos distintos caracterizando os pacientes usuários de bisfosfonatos e não usuários. Para a descrição das lesões foram definidos os seguintes critérios de análise: localização anatômica, tamanho, margens, aspecto interno, relação com estruturas adjacentes, caracterização ou não do padrão saca-bocado (punched-out). Foram identificadas lesões osteolíticas em 100% da amostra tanto na maxila como na mandíbula. O padrão saca-bocado não foi encontrado em nenhuma imagem avaliada, sendo predominante o aspecto de reabsorção óssea generalizada, apresentando áreas com aspecto multilocular, se estendendo por toda a maxila e/ou mandíbula. Observou-se que um número significativamente maior de pacientes não usuários de bisfosfonatos apresentavam margens indefinidas que aqueles com história de uso. Concluise que foi possível estabelecer um protocolo de avaliação para a descrição destas lesões garantindo a padronização das análises. As lesões osteolíticas nos maxilares de pacientes portadores de mieloma múltiplo são predominantes, sendo possíveis de serem diferenciadas apenas com exames acurados, portanto a tomografia computadorizada de feixe cônico demonstrou ser um importante recurso para este fim. (AU)
Multiple myeloma develops from neoplastic cells of plasma cells causing an imbalance in the reabsorption and bone formation, resulting in the appearance of osteolytic lesions, which present a diversity of imaging aspects. The objective of this study was to establish an evaluation protocol, using cone beam computed tomography, based on standardized criteria for the identification and description of the imaging variations of these lesions. A total of 33 examinations of patients with multiple myeloma were evaluated, being subdivided into two distinct groups characterizing users bisphosphonates and nonusers. For the description of the lesions, the following criteria of analysis were defined: anatomical location, size, limits, internal aspect, relation with adjacent structures, characterization or not of the punched-out pattern. Osteolytic lesions were identified in 100% of the sample in the maxilla and the mandible. The punched-out pattern was not found in any of the evaluated images. Generalized bone resorption was predominant, presenting areas with multilocular appearance, extending throughout the maxilla and/or mandible. It was observed a significantly higher number of patients bisphosphonate nonusers presented lesions with indefinite limits than the users. It was concluded that it was possible to establish an evaluation protocol for the description of these lesions, ensuring the standardization of the analyzes. The osteolytic lesions in the jaws of patients with multiple myeloma are predominant, being possible to be differentiated only with accurate exams, therefore cone beam computed tomography has proved to be an important resource for this purpose. (AU)
