Design and Validation of a Spinal Surgical Navigation System Based on Spatial Augmented Reality.

STUDY DESIGN: Prospective observational study.

OBJECTIVE: This article aims to develop a spatial augmented reality-based surgical navigation system to assist in the placement of pedicle screws in minimally invasive spine surgery and to verify the accuracy of this method.

SUMMARY OF BACKGROUND DATA: Due to their high accuracy and good visualization ability, augmented reality surgical navigation systems have been used in minimally invasive surgeries. However, augmented reality does not allow information to be shared and restricts doctors.

METHODS: A surgical navigation system that implements augmented reality based on a projector can be used to realize the external visualization of virtual organs and surgical information through an improved multiple information fusion method. Using fiducial markers and imaging technology, the patient's spatial position is tracked and registered in real time. All the information is accurately fused with the patient's back skin, and the surgeon can see surgical information such as the preoperative plan and bones. Phantom experiments were used to verify the accuracy and effectiveness of the system.

RESULTS: In the phantom experiments, the accuracy of the pedicle screw insertion point on the dummy's skin was 0.441 ± 0.214 mm, the average location error into the dummy's body was 1.645 ± 0.355 mm, and the average axial and sagittal angulation errors were <0.9°.

CONCLUSION: This article introduces and verifies the design of a new surgical navigation system based on spatial augmented reality for lumbar pedicle screw implantation. The system passed a series of phantom accuracy experiments. Compared with the traditional augmented reality navigation system, this system avoids the use of glasses and truly realizes the effect of naked-eye 3D, which is more convenient for doctors to use for communication during an operation.

LEVEL OF EVIDENCE: N/A.