Preoperative Planning Using 3D Reconstructions and Virtual Endoscopy for Location of the Frontal Sinus

Summary

Introduction: Computed tomography (TC) generated tridimensional (3D) reconstructions allow the observation of cavities and anatomic structures of our body with detail. In our specialty there have been attempts to carry out virtual endoscopies and laryngoscopies. However, such application has been practically abandoned due to its complexity and need for computers with high power of graphic processing.

Objective: To demonstrate the production of 3D reconstructions from CTs of patients in personal computers, with a free specific program and compare them to the surgery actual endoscopic images.

Method: Prospective study in which the CTs proper files of 10 patients were reconstructed with the program Intage Realia, version 2009, 0, 0, 702 (KGT Inc., Japan). The reconstructions were carried out before the surgeries and a virtual endoscopy was made to assess the recess and frontal sinus region. After this study, the surgery was digitally performed and stored. The actual endoscopic images of the recess and frontal sinus region were compared to the virtual images.

Results: The 3D reconstruction and virtual endoscopy were made in 10 patients submitted to the surgery. The virtual images had a large resemblance with the actual surgical images.

Conclusion: With relatively simple tools and personal computer, we demonstrated the possibility to generate 3D reconstructions and virtual endoscopies. The preoperative knowledge of the frontal sinus natural draining path location may generate benefits during the performance of surgeries. However, more studies must be developed for the evaluation of the real roles of such 3D reconstructions and virtual endoscopies.

Resumo

Introdução: Reconstruções tridimensionais (3D) geradas de tomografias computadorizadas (TCs) permitem a observação de cavidades e estruturas anatômicas de nosso corpo com riqueza de detalhes. Em nossa especialidade já houve tentativas da realização de endoscopias e laringoscopias virtuais. Entretanto, estas aplicações foram praticamente abandonadas devido à complexidade e necessidade de computadores com alto poder de processamento gráfico.

Objetivo: Demonstrar a confecção de reconstruções 3D a partir de TCs de pacientes em computador pessoal, com programa específico gratuito e compará-las às imagens endoscópicas reais da cirurgia.

Método: Estudo prospectivo em que os arquivos próprios das TCs de 10 pacientes foram reconstruídos com programa Intage Realia, versão 2009, 0, 0, 702 (KGT Inc, Japão). As reconstruções foram realizadas antes das cirurgias e uma endoscopia virtual foi feita para se avaliar a região do recesso e seio frontal. Após este estudo, a cirurgia foi realizada e armazenada digitalmente. As imagens endoscópicas reais da região do recesso e seio frontal foram comparadas às imagens virtuais.

Resultados: A reconstrução 3D e endoscopia virtual foram realizadas nos 10 pacientes submetidos à cirurgia. As imagens virtuais apresentavam grande semelhança visual com as imagens das cirurgias reais.

Conclusão: Demonstramos a possibilidade, com ferramentas relativamente simples e computador pessoal, de se gerar reconstruções 3D e endoscopias virtuais. O conhecimento pré-operatório da localização do caminho de drenagem natural do seio frontal pode vir a gerar benefícios durante a realização das cirurgias. Entretanto, mais estudos devem ser desenvolvidos para a avaliação do real papel destas reconstruções 3D e endoscopias virtuais.

Keywords

computer assisted surgery - video-assisted surgery - tomography - tridimensional image - endoscopy

Palavras-chave

cirurgia assistida por computador - cirurgia vídeo-assistida - tomografia - imagem tridimensional - endoscopia

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