Dual optical channel three-dimensional neuroendoscopy: Clinical application as an assistive technique in endoscopic endonasal surgery

•Efficacy of three-dimensional (3D) endoscopy for evaluation of ventral skull base pathology has been reported in several studies, in addition to being recently reviewed in World Neurosurgery (Zaidi et al., 86:419-413, 2016).•The clinical significance of 3D endoscopy is conventionally discussed with the assumption that the stereoscopic effect is constant among various 3D techniques.•However, we would like to stress that the stereoscopic effect varies according to the integrated 3D technology, which can affect the surgical performance of 3D endoscopy.•In the present study, we report our clinical experience of dual optical channel 3D high-definition neuroendoscopy and discuss its clinical significance.•In addition, we review how depth perception is obtained during endoscopic surgery to gain a better understanding of the efficacy of 3D endoscopic surgery, which has rarely been discussed in studies involving 3D endoscopic endonasal surgery.

Three-dimensional (3D) high-definition endoscopy is an innovative technical advancement that helps surgeons gain precise depth perception and spatial recognition during endoscopic surgery. Here, we describe a new dual optical channel 3D neuroendoscopic technique and its clinical application. We performed endoscopic endonasal surgery on 88 patients using 3D and two-dimensional (2D) endoscopes in conjunction. We evaluated the usefulness of stereoscopic images acquired by dual optical channel 3D endoscopy during endoscopic surgery and compared the image resolution between dual optical channel 3D endoscopy and 2D endoscopy. Additionally, we compared the stereoscopic images acquired by dual optical channel and Visionsense 3D endoscopy in three cases. Combination surgery using 3D and 2D endoscopy was found to be safe. Stereoscopic images were useful in several surgical steps, especially in recognition of complex bony structures, bone drilling, and suprasellar manipulation. The magnitude of binocular disparity was greater in dual optical channel 3D endoscopy than in Visionsense 3D endoscopy. Stereoscopic images acquired by dual optical channel 3D neuroendoscopy were of adequate quality and were useful for endoscopic endonasal surgery. In consideration of its lower image resolution compared to that of 2D high-definition endoscopy, dual optical channel 3D neuroendoscopy can be applied as an assistive technique in endoscopic endonasal surgery. The magnitude of binocular disparity is one of the key factors to be considered for evaluation of the clinical significance of 3D endoscopy.