Feasibility and Accuracy of Thoracolumbar Pedicle Screw Placement Using an Augmented Reality Head Mounted Device

Abstract

Background: To investigate the accuracy of augmented reality (AR) navigation using the Magic Leap head mounted device (HMD), pedicle screws were minimally invasively placed in four spine phantoms. Methods: AR navigation provided by a combination of a conventional navigation system integrated with the Magic Leap head mounted device (AR-HMD) was used. Forty-eight screws were planned and inserted into Th11-L4 of the phantoms using the AR-HMD and navigated instruments. Postprocedural CT scans were used to grade the technical (deviation from the plan) and clinical (Gertzbein grade) accuracy of the screws. The time for each screw placement was recorded. Results: The mean deviation between navigation plan and screw position was 1.9 ± 0.7 mm (1.9 [0.3–4.1] mm) at the entry point and 1.4 ± 0.8 mm (1.2 [0.1–3.9] mm) at the screw tip. The angular deviation was 3.0 ± 1.4° (2.7 [0.4–6.2]°) and the mean time for screw placement was 130 ± 55 s (108 [58–437] s). The clinical accuracy was 94% according to the Gertzbein grading scale. Conclusion: The combination of an AR-HMD with a conventional navigation system for accurate minimally invasive screw placement is feasible and can exploit the benefits of AR in the perspective of the surgeon with the reliability of a conventional navigation system.

Mixed-Reality-Assisted Puncture of the Common Femoral Artery in a Phantom Model

“…Although currently commercially available navigational systems (without MR) have demonstrated positional errors of ≤2 mm, the error resulting from registration with the MR environment has yet to be investigated [32]. In the present study, the cumulative positional error between initial imaging registration in the navigational system and the actual MRassisted puncture of the femoral artery, including the human error during the puncture itself, was in line with previously reported accuracies in spine surgery with a similar experimental set-up using an HMD and a commercially available navigation system [22,23,33]. Although the quantified positional error was generally sufficient for CFA access in a phantom model, with 14/15 technically successful punctures (93.3%), there was one failed puncture (6.7%) and 1/3 of punctures were outside the mid portion of the targeted area.…”

“…Different methods of registration have been investigated, ranging from manual registration and automatic registration using optical tracking markers to registration assisted by commercially available navigation systems. The most investigated clinical application in the past has been pedicle screw placement during spine surgery, which has demonstrated promising initial results in several pilot studies [21][22][23][24][25][26]. In the field of vascular surgery, initial studies have also been conducted to investigate the potential of MR [16,27,28].…”

Augmenting Performance: A Systematic Review of Optical See-Through Head-Mounted Displays in Surgery

“…Intraoperative endoscope video is the primary real-time data source for laparoscopic and endoscopic procedures and robot-assisted surgery [ 56 , 82 ]. Cone-beam CT employs a similar imaging strategy as CT and improves on some limitations of X-ray fluoroscopy, mainly the 2D nature of the data, by providing the capacity for a 3D snapshot of the intraoperative patient anatomy [ 84 , 85 ]. The final intraoperative data sources were from patient sensors and monitoring equipment [ 86 ] and simulated intraoperative data [ 73 ].…”

“…After preoperative imaging, Digital Imaging and Communications in Medicine (DICOM) formatted data are typically provided which can be read in an open source library, such as 3D Slicer ( , accessed on 23 March 2022) [ 46 , 65 , 74 , 87 ], or proprietary software, such as Mimics ( , accessed on 23 March 2022) [ 47 , 61 , 88 ] or Brainlab ( , accessed on 23 March 2022) [ 67 , 84 ]. Surface rendered models provide enormous utility due to their ease of creation, lightweight model representation, and additional modifiable visualization properties, such as color, transparency, wireframe representations, and heatmaps [ 89 ].…”

“…External tracking using stereo RGB is subject to the same line-of-sight challenges as with infrared tracking. Overall, in the external tracking-led approach, the OST-HMD served as a display medium for existing surgical navigation suites or sensors [ 54 , 68 , 84 , 93 , 95 ], replacing the traditional 2D computer monitor as the primary method of visualization.…”