Registration for Image Integration of Intraoperative MRI and Endoscope, using MRI-compatible Manipulator

This paper is the first discussion on the registration of intraoperative MRI and endoscope using Polaris and MRI-compatible endoscope manipulator. An endoscope has been popular in minimally invasive surgery due to its less-invasive, realtime, and fine observations in body cavity. However, because its view is so limited, it's difficult to know the surrounding structures. Intraoperative MRI has been developed recently, for surgeon to comprehend the anatomical structures behind the surface and changes caused by operation during surgery. Therefore it is clinically significant that the intraoperative MRI visualize the structures behind the narrow approach in an endoscopic surgery. For this purpose, we have studied MRI-compatible endoscope and MRI-compatible endoscope manipulator to position the endoscope for a transnasal neurosurgery. The image capture, pan, and tilt are not sufficient for image integration. It is helpful for effective navigation where the point viewed in endoscope is located in MRI, and where the point viewed in MRI is located in endoscopic view. In other words, the registration in MRI and endoscope is necessary. In this paper, we would discuss registration for image integration of intraoperative MRI and endoscope, using MRI-compatible endoscope manipulator. The accuracies of 3 different registration routes were examined preclinically using a MRIendoscope visible phantom whose geometry was known.