Computed tomography imaging strategies and perspectives in orbital fractures

OBJECTIVE: The objective of this study was to demonstrate the sensitivity and specificity of multislice computed tomography (CT) for diagnosis of orbital fractures following different protocols, using an independent workstation. MATERIALS AND METHODS: CT images of 36 patients with maxillofacial fractures (symptomatic to orbit region) who were submitted to multislice CT scanning were analyzed, retrospectively. The images were interpreted based on 5 protocols, using an independent workstation: 1) axial (original images); 2) multiplanar reconstruction (MPR); 3) 3D images; 4) association of axial/MPR/3D images and 5) coronal images. The evaluated anatomical sites were divided according to the orbital walls: lateral (with or without zygomatic frontal process fracture); medial; superior (roof) and inferior (anterior, medial). The collected data were analyzed statistically using a validity test (Youden's J index; p<0.05). The clinical and/or surgical findings (medical records) were considered as the gold standard to corroborate the diagnosis of the anatomical localization of the orbital fracture. RESULTS: 3D-CT scanning presented sensitivity of 78.9 percent, which was not superior to that of MPR (84.0 percent), axial/MPR/3D (90.5 percent) and coronal images (86.1 percent). On the other hand, the diagnostic value of axial images was considered limited for orbital fractures region, with sensitivity of 44.2 percent. CONCLUSIONS: Except for the axial images, which presented a low sensitivity, all methods evaluated in this study showed high specificity and sensitivity for the diagnosis of orbital fractures according to the proposed methodology. This protocol can add valuable information to the diagnosis of fractures using the association of axial/MPR/3D with multislice CT.

Computed tomography imaging strategies and perspectives in orbital fractures.

OBJECTIVE: The objective of this study was to demonstrate the sensitivity and specificity of multislice computed tomography (CT) for diagnosis of orbital fractures following different protocols, using an independent workstation. MATERIALS AND METHODS: CT images of 36 patients with maxillofacial fractures (symptomatic to orbit region) who were submitted to multislice CT scanning were analyzed, retrospectively. The images were interpreted based on 5 protocols, using an independent workstation: 1) axial (original images); 2) multiplanar reconstruction (MPR); 3) 3D images; 4) association of axial/MPR/3D images and 5) coronal images. The evaluated anatomical sites were divided according to the orbital walls: lateral (with or without zygomatic frontal process fracture); medial; superior (roof) and inferior (anterior, medial). The collected data were analyzed statistically using a validity test (Youden's J index; p<0.05). The clinical and/or surgical findings (medical records) were considered as the gold standard to corroborate the diagnosis of the anatomical localization of the orbital fracture. RESULTS: 3D-CT scanning presented sensitivity of 78.9%, which was not superior to that of MPR (84.0%), axial/MPR/3D (90.5%) and coronal images (86.1%). On the other hand, the diagnostic value of axial images was considered limited for orbital fractures region, with sensitivity of 44.2%. CONCLUSIONS: Except for the axial images, which presented a low sensitivity, all methods evaluated in this study showed high specificity and sensitivity for the diagnosis of orbital fractures according to the proposed methodology. This protocol can add valuable information to the diagnosis of fractures using the association of axial/MPR/3D with multislice CT.

Validity of multislice computerized tomography for diagnosis of maxillofacial fractures using an independent workstation.

OBJECTIVE: The purpose of this study was to demonstrate the sensitivity and specificity of multislice computerized tomography (CT) for diagnosis of maxillofacial fractures following specific protocols using an independent workstation. STUDY DESIGN: The study population consisted of 56 patients with maxillofacial fractures who were submitted to a multislice CT. The original data were transferred to an independent workstation using volumetric imaging software to generate axial images and simultaneous multiplanar (MPR) and 3-dimensional (3D-CT) volume rendering reconstructed images. The images were then processed and interpreted by 2 examiners using the following protocols independently of each other: axial, MPR/axial, 3D-CT images, and the association of axial/MPR/3D images. The clinical/surgical findings were considered the gold standard corroborating the diagnosis of the fractures and their anatomic localization. The statistical analysis was carried out using validity and chi-squared tests. RESULTS: The association of axial/MPR/3D images indicated a higher sensitivity (range 95.8%) and specificity (range 99%) than the other methods regarding the analysis of all regions. CONCLUSION: CT imaging demonstrated high specificity and sensitivity for maxillofacial fractures. The association of axial/MPR/3D-CT images added important information in relationship to other CT protocols.

CT-based analysis of malignant tumor volume and localization: a preliminary study

O propósito desta pesquisa foi correlacionar medidas volumétricas de lesões malignas em reconstruções tridimensionais (TC-3D) com a resposta ao tratamento e verificar o grau de envolvimento ósseo dessas lesões, aplicando-se protocolos de imagem específicos associados à computação gráfica. Foram estudados 17 indivíduos portadores de lesões malignas maxilofaciais que haviam sido submetidos à tomografia computadorizada espiral (TC-2D). Os dados originais foram transferidos para uma estação de trabalho independente, utilizando um programa para imagens volumétricas, com o qual dois observadores obtiveram medidas de área e volume das lesões, independentemente, 3 vezes cada um, no pré e pós-tratamento. O protocolo de segmentação foi aplicado para avaliação do comprometimento ósseo. A diferença entre os valores obtidos na análise da TC e no padrão ouro não foi considerada significante (p > 0,05). Considerando o envolvimento ósseo, obtiveram-se três falsos-negativos em análise das reconstruções multiplanares (TC-RMP) e nenhum falso-negativo em análise da TC-3D por meio do protocolo de segmentação. A utilização de recursos como reconstrução em TC-3D pode ser um fator diferencial e de grande valia para aumentar opções quanto a localização, dimensões e esclarecimento de componentes de diversas lesões.

CT-based analysis of malignant tumor volume and localization. A preliminary study.

The purpose of this study was to correlate 3D-CT (3D computed tomography) volume measurements of malignant tumors with the response to treatment, and to observe bone invasion in these lesions applying a specific imaging protocol. We analyzed 17 individuals with maxillofacial malignant lesions who were submitted to spiral CT (2D-CT). The original data were transferred to an independent workstation using a 3D volume rendering package software, which was used by two examiners to obtain area and volume measurements of the lesions, independently, three times each, prior to and after treatment. The segmentation protocol was applied for the assessment of bone involvement. The difference between imaging and gold standard values was not considered significant (p > 0.05). Regarding bone invasion, three false-negatives were obtained using MPR-CT (multiplanar reconstruction) and no false-negatives were obtained using the 3D segmentation protocol. The use of 3D-CT may be a differential and important factor for expanding options regarding the localization, dimension, and clarification of lesion components.

3D-CT vascular setting protocol using computer graphics for the evaluation of maxillofacial lesions / Protocolo vascular por meio da 3D-Tc utilizando a computaçäo gráfica para avaliaçäo de lesöes maxilo-faciais

Neste trabalho, demonstramos os aspectos de um granuloma central de células gigantes por meio da tomografia computadorizada (TC) em espiral baseada na reconstruçäo de imagem em três dimensöes (3D), utilizando a computaçäo gráfica, e a importância do protocolo vascular permitindo um melhor diagnóstico, visualizaçäo e contendo dimensöes da lesäo. Foram analisados 21 pacientes com lesöes maxilo-faciais de origens neoplásicas e proliferativas. Dois radiologistas analisaram as imagens. A utilidade da interaçäo da reconstruçäo da imagem por meio da computaçäo gráfica, especialmente utilizando o protocolo vascular para análises qualitativas e quantitativas para o diagnóstico, planejamento de tratamento e evoluçäo, assim como para a localizaçäo da extensäo da lesäo foi demonstrada. Isto é um importante adjunto para a evoluçäo destas lesöes em relaçäo a cortes axiais em TC e para imagens por meio de 3D-TC para estruturas ósseas

Three dimensional spiral computed tomography for maxillofacial tumors: quantitative assessment by a computer graphics-aided system / Tomografia computadorizada tridimensional em espiral para tumores maxilo-faciais: análise quantitativa por meio de um sistema de computaçäo gráfica

O trabalho apresenta aspectos radiográficos da reconstruçäo em @D e em 3D por meio da tomografia computadorizada em espiral em um paciente com linfoma com origem no seio maxilar do lado esquerdo. Foi demonstrado que 3D-TC é um importante método na localizaçäo e na determinaçäo da extensäo de tumores maxilo-faciais, considerando-se principalmente a obtençäo área, medidas volumétricas e lineares dos mesmos. A nova tecnologia proveniente da computaçäo gráfica por meio da 3D-TC utilizando sistemas de imagens interativos demonstraram uma grande melhoria na qualidade da imagem e em resultados finais quando utilizadas propriedades do programa por diferentes protocolos em 3D. Essas imagens por 3D-TC säo consideradas importantes para a análise da destruiçäo óssea e do envolvimento de tecidos moles para o planejamento e acompanhamento do tratamento. Nós concluímos que é importante analisar neoplasias que afetam o complexo maxilo-facial pela computaçäo gráfica utilizando a reconstruçäo em 3D