"The Hollowman" - a virtual reality tool in cranio-maxillofacial surgery

Abstract A virtual reality tool for computer-assisted surgery named “The Hollowman” is presented. This allows for a visual tracking of real anatomical structures in superposition with volume rendered CT or MRI scans and thus can be used for navigated translocation of bony segments. For an evaluation study “The Hollowman” was used in orthognatic surgery to control the translocation of the maxilla after Le Fort I osteotomy within a bimaxillary procedure. Up to now, four patients have been included. The tool has proven very valuable especially in complex nonlinear translocations of the maxilla as the surgeon could directly visualise the position of the mobilised bone in relation to the preoperatively planned situation. The application to other types of interventions in cranio-maxillofacial surgery associated with movement of bony segments as Le Fort III osteotomy, fronto-orbital advancement and cranial vault reshaping or reconstruction seems to be considerable as well.