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.

OBJETIVO: Os autores estabeleceram uma metodologia para avaliar carcinoma espinocelular de cabeça e pescoço, identificando e distinguindo áreas de grande atividade metabólica dentro da neoplasia, associando dados simultaneamente adquiridos, obtidos por diferentes modalidades de aquisição de imagens, combinando informações metabólicas e anatômicas num único exame. MATERIAIS E MÉTODOS: A população estudada consistiu de 17 pacientes com carcinoma espinocelular pertencentes aos arquivos do Departamento de Imagem do Hospital do Câncer, São Paulo. As imagens de tomografia computadorizada (TC) e da tomografia por emissão de pósitrons (PET) com 2-[F-18]-fluoro-2-deoxi-d-glucose (18F-FDG-PET) foram simultaneamente adquiridas utilizando aparelho não dedicado. Os dados originais foram transferidos para uma estação de trabalho independente com o programa Entegra 2NT para gerar a fusão de imagens da PET e TC. RESULTADOS: Os achados foram definidos como positivos na presença de focos com aumento da concentração do radiofármaco em áreas não relacionadas à sua distribuição normal. CONCLUSÃO: A fusão de imagens simultaneamente adquiridas num único exame (18F-FDG-PET e TC) possibilitou o mapeamento topográfico metabólico das lesões estudadas e foi possível localizar áreas de maior atividade metabólica dentro do próprio tumor, verificando recidivas ou metástases, possibilitando aumentar as opções quanto ao planejamento radioterápico ou cirúrgico.

OBJECTIVE: The authors have established a methodological approach to evaluate head and neck squamous cell carcinoma aiming at identifying and distinguishing high metabolic activity inside the lesion, combining in a single examination, functional, metabolic and morphological data simultaneously acquired by means of different non-dedicated positron emission tomography (PET)-computed tomography (CT) device. MATERIALS AND METHODS: The study population included 17 patients with head and neck squamous cell carcinoma submitted to a non-dedicated 18F-FDG-PET imaging at Department of Diagnostic Imaging of Hospital do Câncer, São Paulo, SP, Brazil. CT and 18F-FDG-PET images were simultaneously acquired in a non-dedicated device. The original data were transferred to an independent workstation by means of the Entegra 2 NT software to generate PET-CT imaging fusion. RESULTS: The findings were defined as positive in the presence of a well defined focal area of increased radiopharmaceutical uptake in regions not related with the normal biodistribution of the tracer. CONCLUSION: The fusion of simultaneously acquired images in a single examination (18F-FDG-PET and CT) has allowed the topographic-metabolic mapping of the lesion as well as the localization of high metabolic activity areas inside the tumor, indicating recidivation or metastasis and widening the array of alternatives for radiotherapy or surgical planning.

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.

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.