Virtual neuroendoscopy: MRI-based three-dimensional visualization of the cranial nerves in the posterior cranial fossa.

This article presents the advances of three-dimensional (3D) virtual neuroendoscopy of the cranial nerves (CN) in the posterior fossa. Interactive 3D visualizations were generated and the anatomical landmarks, such as the root entry/exit zones (REZ) and cisternal segments of the CN were evaluated. Twenty patients (M:F, 6:14) with trigeminal neuralgia (TN) underwent MRI constructive interference in steady state (MRI(CISS)) imaging and subsequent 3D visualization based on explicit segmentation of the MRI(CISS) data and interactive evaluation with direct volume rendering including implicit segmentation. The 3D topography of the interesting CN V-X were evaluated with interactive and virtual neuroendoscopy. The anatomical landmarks of the CN V-X could be visualized in all 20 cases (100%). The systematic application of virtual neuroendoscopy could be realized in all patients for the non-invasive observation of the CN without any technical difficulties. Interactive 3D visualization using explicit and implicit techniques for segmentation, and 3D direct volume rendering is demonstrated to successfully identify 3D neurovascular relations in patients with trigeminal neuralgia. It has the ability to provide a useful tool for surgeons in the pre- and intraoperative evaluation of such cases.