Surgical Navigation System and Method Using Audio Feedback

We discuss an experimental audio feedback system and method for positional guidance in real-time surgical instrument placement tasks. This system is intended for future usability testing in order to ascertain the efficacy of the use of the aural modality for assisting surgical placement tasks in the operating room. The method is based on translating spatial parameters of a surgical instrument or device, such as its position or velocity with respect to some coordinate system, into a set of audio feedback parameters along the coordinates of a generalised audio space. Error signals that correspond to deviations of the actual instrument trajectory from an optimal trajectory are transformed into a set of audio signals that indicate to the user whether correction is necessary. An experimental hardware platform was assembled using commercially available hardware. A system for 3-D modelling, surgical procedure planning, real-time instrument tracking and audio generation was developed. Prototype software algorithms for generating audio feedback as a function of instrument navigation were designed and implemented. The system is sufficient for future usability testing. This technology is still in an early stage of development, with formal usability and performance testing yet to be done. However, informal usability experiments in the course of the basic engineering process indicate the use of audio is a promising alternative to, or redundancy measure in support of visual display technology for intra-operative navigation.