  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 developed an AR biopsy navigation system
with 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. Retro-reflective tool tracking is implemented on
the HoloLens 2, enabling 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, for puncture accuracy and biopsy
time, comparing to traditional methods. Results: Our proposed framework enables
ultrasound visualization in AR with only $16.22\pm11.45ms$ additional latency.
Navigation accuracy reached $1.23\pm 0.68mm$ in the image plane and $0.95\pm
0.70mm$ outside the image plane. Remarkably, the utilization of our system led
to $98\%$ and $95\%$ success rate in out-of-plane and in-plane biopsy.
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.
