Towards three-dimensional fusion of infrared guidance measurements for biopsy procedures: Some preliminary results and design considerations

A system comprising of a digital infrared sensitive camera and high intensity infrared illuminator was used to track infrared reflective tape on a coaxial biopsy needle. Data was sent in real-time to a computer where needle position with respect to the desired path was displayed in 2D, enabling instant corrections in needle trajectory by the operator. In this preliminary study, two operators each performed 30 simulated computed tomography (CT) guided biopsies of targets within a phantom. The operators alternated between freehand and infrared guided techniques with the axial angular error statistically compared. The mean axial angular error significantly decreased for both operators for the infrared guidance technique compared to the freehand method. The operators found the 2D simulation and training system easy to learn and intuitive to use despite no prior training on the device. In this paper we also look at further developing the 2D system (used in the simulated CT biopsy trials) into a 3D needle tracking system. We consider what is involved in its integration into a volume rendering simulation and training module, which would allow real-time needle placement in any plane on simulated patient anatomy. The proposed simulation and training module would further help improve the operator´s spatial reference, improve accuracy, increase confidence, decrease radiation exposure to the patient and help reduce the time it takes to perform a biopsy.