P18.01 Indocyanine green fluorescence endoscope: the useful points in endonasal transsphenoidal surgery

Abstract

AbstractIntroduction:For the safe operation, exact orientation during endoscopic endonasal transsphenoidal surgery (ETSS) is essential. Neuronavigation systems can be pointed at exact sites, but their spatial resolution power is too low for the detection of vessels that cannot be seen on MRI images. On Doppler sonographs the shape of concealed arteries and veins cannot be visualized. To solve these problems we evaluated the clinical usefulness of the indocyanine green (ICG) endoscope.Materials and Methods:We enrolled 38 patients with pituitary adenomas (n = 26), tuberculum sellae meningiomas (n = 4), craniopharyngiomas (n = 3), and chordomas (n = 2); there was one patient each with Rathke’s cleft cyst, a dermoid cyst, and fibrous dysplasia. After opening the sphenoid sinus and placing the ICG endoscope, we injected 12.5 mg of ICG into a peripheral vein as a bolus and observed the internal carotid arteries (ICAs), cavernous sinus, intercavernous sinus, and pituitary. Intraoperative real-time measurement of ICG signals was performed in 4 of microadenomas.Results:The ICA was clearly identified by a strong fluorescence signal through the dura mater and the covering thin bone. The cavernous sinus and the attachment of tuberculum sellae meningiomas were identified through the dura matter. At the final inspection after tumor removal, perforators to the brain, optic nerves, chiasm, and pituitary stalk were visualized. ICG fluorescence signals from the hypophyseal arteries were strong enough to see and spread to the area of perfusion with the passage of time. Elevation of ICG signals was relatively delayed in microadenoma compared to the area of normal pituitary.Conclusions:In ETSS, the real time and high resolution image of ICA and cavernous sinus with the ICG endoscope is strongly useful. We suggest that the real-time observation of the blood supply to the optic nerves and pituitary helps to predict the preservation of their function, and different elevation pattern of ICG signal between microadenoma and normal pituitary helps to identify margin of them.