Impact of indocyanine green fluorescent image-guided surgery for parapharyngeal space tumours

In parapharyngeal space dissection, significant complications such as dysphagia and carotid artery rupture have been reported. In order to resect tumours safely in narrow parapharyngeal space, we propose indocyanine green (ICG) florescence image for navigation surgery.ObjectiveTo evaluate the usefulness of ICG fluorescent image-guided surgery for parapharyngeal space tumours.Methods0.5 mg/kg of ICG was injected via the cephalic vein. Observation of the fluorescent image was performed with HEMS (HyperEye Medical System) at 10–30 min after injection. At first, the position of the tumour was marked over pharyngeal mucosa according to ICG fluorescence imaging with HEMS. We also confirmed submucosal tumours hidden under fascia using HEMS imaging again and resected them.ResultsAll tumours displayed bright fluorescence emissions which clearly contrasted with the normal structures. Even with the submucosal tumour covered with and obscured by fasciae, we could observe the tumour clearly under HEMS imaging. Tumours behind the carotid artery and lower cranial nerves also were displayed bright fluorescence emissions and were clearly detected. As a result, we could completely remove the tumour safely and noninvasively to preserve pharyngeal functions.ConclusionICG fluorescence imaging is effective for the detection and resection of the parapharyngeal space tumours with preserving functions.