The VisAR augmented reality surgical guidance system (Novarad) is a highly accurate, emerging technology for navigating both open and minimally invasive spine surgery (MISS) techniques with off-the-shelf headset hardware, according to research published in the journal Spine by Wendell Gibby (Provo, USA), and surgeons from the University of Utah, Georgetown University and University of Washington.
The aim of the recently published study was to determine the accuracy of pedicle screw placement using VisAR for open spine and MISS procedures.
Collectively, seven cadavers were instrumented with 124 thoracolumbar pedicle screws using VisAR. A total of 65 screws were inserted into four donors using open dissection spine surgery and 59 screws were positioned in three donors with a MISS procedure. For both open and MISS, VisAR was used exclusively for pedicle screw navigation.
Overall, the 124 pedicle screws were inserted with 96% accuracy (Gertzbein-Robbins [GRS] grades A and B). The combined angle of error was 2.4° and the distance error was 1.9 mm.
Of the 65 pedicle screws inserted during open surgery, 63 (96.9%) were positioned correctly (59 GRS grade A and four grade B). The remaining two screws were GRS grade C and were both lateral breaches.
Of the 59 pedicle screws inserted during MISS, 56 screws (94.9%) were positioned correctly (54 GRS grade A and two grade B). The remaining three screws were graded as C.
Gibby, who is CEO of Novarad, said: “The VisAR technology holds great promise for improving patient care by reducing operating room (OR) times, decreasing radiation to the patient and OR personnel, improving surgical accuracy and significantly democratising access due to much lower cost than traditional navigation and robotic surgical approaches.”
VisAR recently received US Food and Drug Administration (FDA) 510(k) clearance. The VisAR system translates the patient’s radiologic imaging data into a 3D hologram which the company says is precisely superimposed on the patient by hologram-to-patient optical code alignment. The system is an off-the-shelf HoloLens 2 (Microsoft) AR visor, which uses transformative software developed by Novarad for precision guided open and minimally invasive spine surgery.