Image stitching of sphenoid sinuses from monocular endoscopic views

For operations of the pituitary glands, the most subtle method is an intervention through the paranasal and especially through the sphenoid sinus. To avoid dangerous interference with adjacent organs and nerves, the surgeon has to orient himself in the very small sphenoid cavity and navigate across the hollow space to break through the sellar floor to the pituitary gland above. Especially in reoperations or anatomical variants such as so-called kissing carotids, transsphenoidal surgery is a challenge even in experienced hands. To support such a surgery, various imaging modalities can be applied such as CT, MRI or endoscopy. While pre-operative MRI or CT-data can be used for intervention planning and navigation support, endoscopy can be applied intra-operatively for the examination of surfaces inside the sphenoid sinus. In this work, we present initial experiments and results from real-time panorama-endoscopy of the sphenoid sinus for navigation and orientation support, based on monocular endoscopic sequences of a skull phantom, yielding partial reconstructions of the walls of the sphenoid sinus.