Usefulness of an Image Fusion Model Using Three-Dimensional CT and MRI with Indocyanine Green Fluorescence Endoscopy as a Multimodal Assistant System in Endoscopic Transsphenoidal Surgery.

Akihiro Inoue,Shiro Ohue,Shohei Kohno,Naoya Nishida,Takanori Ohnishi,Yawara Nakamura,Yoshihiro Ohtsuka,Shirabe Matsumoto

doi:10.1155/2015/694273

Abstract

Purpose. We investigate the usefulness of multimodal assistant systems using a fusion model of preoperative three-dimensional (3D) computed tomography (CT) and magnetic resonance imaging (MRI) along with endoscopy with indocyanine green (ICG) fluorescence in establishing endoscopic endonasal transsphenoidal surgery (ETSS) as a more effective treatment procedure. Methods. Thirty-five consecutive patients undergoing ETSS in our hospital between April 2014 and March 2015 were enrolled in the study. In all patients, fusion models of 3D-CT and MRI were created by reconstructing preoperative images. In addition, in 10 patients, 12.5 mg of ICG was intravenously administered, allowing visualization of surrounding structures. We evaluated the accuracy and utility of these combined modalities in ETSS. Results. The fusion model of 3D-CT and MRI clearly demonstrated the complicated structures in the sphenoidal sinus and the position of the internal carotid arteries (ICAs), even with extensive tumor infiltration. ICG endoscopy enabled us to visualize the surrounding structures by the phasic appearance of fluorescent signals emitted at specific consecutive elapsed times. Conclusions. Preoperative 3D-CT and MRI fusion models with intraoperative ICG endoscopy allowed distinct visualization of vital structures in cases where tumors had extensively infiltrated the sphenoidal sinus. Additionally, the ICG endoscope was a useful real-time monitoring tool for ETSS.

Highlights

Endoscopic endonasal transsphenoidal surgery (ETSS) has become a more common procedure in the treatment of midline skull-based lesions such as pituitary tumors [1,2,3,4,5,6]
We investigate the usefulness of a fusion model of 3D-computed tomography (CT) and magnetic resonance imaging (MRI) along with an indocyanine green (ICG) endoscope as a multimodal assistant system in ETSS, in cases requiring identification of the internal carotid arteries (ICAs) for safe and maximum resection of the tumor
Based on images from the fusion model, we evaluated the structure of the sphenoidal sinus and location of the vital structures, including the bony prominences of the ICAs and optic canals buried under the invasive tumor, and made comparisons with the actual endoscopic views observed intraoperatively

Summary

Introduction

Endoscopic endonasal transsphenoidal surgery (ETSS) has become a more common procedure in the treatment of midline skull-based lesions such as pituitary tumors [1,2,3,4,5,6]. ETSS offers several technical advantages, including wider, multidirectional views of the operative field [7, 8] In spite of these advantages, there is significant risk of injury to the surrounding vital structures, when the tumors have extensively invaded into the sphenoidal sinus and when the bony components of the skull base have been destroyed. We have reconstructed 3D-CT models from 2D-CT images to allow more accurate visualization of the anatomical orientation of the nasal cavity and paranasal sinuses With these models, we can precisely locate vital structures, such as the internal carotid arteries (ICAs) and optic nerves, as well as the anatomical relationships between these structures and the sellar floor. In other cases, where the tumor has extensively infiltrated the cavernous sinus and largely extends into the suprasellar region, it becomes very difficult to identify the ICAs and the normal pituitary gland

Methods

Results

Discussion

Conclusion