Navigate biopsy with ultrasound under augmented reality device: Towards higher system performance

Purpose: Biopsies play a crucial role in determining the classification and staging of tumors. Ultrasound is frequently used in this procedure to provide real-time anatomical information. Using augmented reality (AR), surgeons can visualize ultrasound data and spatial navigation information seamlessly integrated with real tissues. This innovation facilitates faster and more precise biopsy operations. Methods: We have developed an augmented reality biopsy navigation system characterized by low display latency and high accuracy. Ultrasound data is initially read by an image capture card and streamed to Unity via net communication. In Unity, navigation information is rendered and transmitted to the HoloLens 2 device using holographic remoting. Concurrently, a retro-reflective tool tracking method is implemented on the HoloLens 2, enabling the simultaneous tracking of the ultrasound probe and biopsy needle. Distinct navigation information is provided during in-plane and out-of-plane punctuation. To evaluate the effectiveness of our system, we conducted a study involving ten participants, assessing puncture accuracy and biopsy time in comparison to traditional methods. Results: Ultrasound image was streamed from the ultrasound device to augmented reality headset with 122.49±11.61ms latency, while only 16.22±11.25ms was taken after data acquisition from image capture card. Navigation accuracy reached 1.23±0.68mm in the image plane and 0.95±0.70mm outside the image plane, within a depth range of 200 millimeters. Remarkably, the utilization of our system led to 98% and 95% success rate in out-of-plane and in-plane biopsy, among ten participants with little ultrasound experience. Conclusion: To sum up, this paper introduces an AR-based ultrasound biopsy navigation system characterized by high navigation accuracy and minimal latency. The system provides distinct visualization contents during in-plane and out-of-plane operations according to their different characteristics. Use case study in this paper proved that our system can help young surgeons perform biopsy faster and more accurately.