Expanding the limits of endoscopic intraorbital tumor resection using 3-dimensional reconstruction / Expandindo os limites da ressecção endoscópica de tumor intraorbital utilizando reconstrução tridimensional

Abstract Introduction: Endoscopic orbital surgery is a nascent field and new tools are required to assist with surgical planning and to ascertain the limits of the tumor resectability. Objective: We purpose to utilize three-dimensional radiographic reconstruction to define the theoretical lateral limit of endoscopic resectability of primary orbital tumors and to apply these boundary conditions to surgical cases. Methods: A three-dimensional orbital model was rendered in 4 representative patients presenting with primary orbital tumors using OsiriX open source imaging software. A 2-Dimensional plane was propagated between the contralateral nare and a line tangential to the long axis of the optic nerve reflecting the trajectory of a trans-septal approach. Any tumor volume falling medial to the optic nerve and/or within the space inferior to this plane of resectability was considered theoretically resectable regardless of how far it extended lateral to the optic nerve as nerve retraction would be unnecessary. Actual tumor volumes were then superimposed over this plan and correlated with surgical outcomes. Results: Among the 4 lesions analyzed, two were fully medial to the optic nerve, one extended lateral to the optic nerve but remained inferior to the plane of resectability, and one extended both lateral to the optic nerve and superior to the plane of resectability. As predicted by the three-dimensional modeling, a complete resection was achieved in all lesions except one that transgressed the plane of resectability. No new diplopia or vision loss was observed in any patient. Conclusion: Three-dimensional reconstruction enhances preoperative planning for endoscopic orbital surgery. Tumors that extend lateral to the optic nerve may still be candidates for a purely endoscopic resection as long as they do not extend above the plane of resectability described herein.

Resumo Introdução: A cirurgia orbital endoscópica é um campo emergente e são necessárias novas ferramentas para auxiliar no planejamento cirúrgico e determinar os limites da ressecabilidade tumoral. Objetivo: Usar a reconstrução radiográfica tridimensional para definir o limite lateral teórico de ressecabilidade endoscópica de tumores orbitais primários e aplicar essas condições de limites a casos cirúrgicos. Método: Um modelo orbital tridimensional foi aplicado a quatro pacientes representativos com tumores orbitais primários utilizando o software de imagem de fonte aberta OsiriX. Um plano bidimensional foi propagado entre a narina contralateral e uma linha tangencial ao eixo longo do nervo óptico que reflete a trajetória de uma abordagem transeptal. Qualquer volume de tumor situado medialmente ao nervo óptico e/ou dentro do espaço inferior a esse plano de ressecabilidade foi teoricamente considerado ressecável, independentemente de quão longe ele se estendia até o nervo óptico, pois a retração do nervo seria desnecessária. Os volumes reais do tumor foram então sobrepostos sobre esse plano e correlacionados com os resultados cirúrgicos. Resultados: Entre as quatro lesões analisadas, duas eram totalmente mediais ao nervo óptico, uma se estendia lateralmente ao nervo óptico, mas permaneceu inferior ao plano de ressecabilidade, e uma se estendia lateralmente ao nervo óptico e superior ao plano de ressecabilidade. Conforme previsto pelo modelo tridimensional, uma ressecção completa foi obtida em todas as lesões, exceto uma, que transgrediu o plano de ressecabilidade. Nenhuma nova diplopia ou perda de visão foi observada em qualquer paciente. Conclusão: A reconstrução tridimensional melhora o planejamento pré-operatório para a cirurgia orbital endoscópica. Os tumores que se estendem lateralmente ao nervo óptico podem ainda ser candidatos à ressecção puramente endoscópica, desde que não se estendam além do plano de ressecabilidade aqui descrito.

Three-dimensional Evaluation of Nasal Surgery in Patients with Obstructive Sleep Apnea / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Obstructive sleep apnea (OSA) is a common sleep disorder and is characterized by airway collapse at multiple levels of upper airway. The effectiveness of nasal surgery has been discussed in several studies and shows a promising growing interest. In this study, we intended to evaluate the effects of nasal surgery on the upper airway dimensions in patients with OSA using three-dimensional (3D) reconstruction of cone-beam computed tomography (CT).</p><p><b>METHODS</b>Twelve patients with moderate to severe OSA who underwent nasal surgery were included in this study. All patients were diagnosed with OSA using polysomnography (PSG) in multi sleep health centers associated with Massachusetts General Hospital, Massachusetts Eye and Ear Infirmary and the Partners Health Care from May 31, 2011 to December 14, 2013. The effect of nasal surgery was evaluated by the examination of PSG, subjective complains, and 3D reconstructed CT scan. Cross-sectional area was measured in eleven coronal levels, and nasal cavity volume was evaluated from anterior nasal spine to posterior nasal spine. The thickness of soft tissue in oral pharynx region was also measured.</p><p><b>RESULTS</b>Five out of the 12 patients were successfully treated by nasal surgery, with more than 50% drop of apnea-hypopnea index. All the 12 patients showed significant increase of cross-sectional area and volume postoperatively. The thickness of soft tissue in oral pharynx region revealed significant decrease postoperatively, which decreased from 19.14 ± 2.40 cm 2 and 6.11 ± 1.76 cm 2 to 17.13 ± 1.91 cm 2 and 5.22 ± 1.20 cm 2 .</p><p><b>CONCLUSIONS</b>Nasal surgery improved OSA severity as measured by PSG, subjective complaints, and 3D reconstructed CT scan. 3D assessment of upper airway can play an important role in the evaluation of treatment outcome.</p>