Augmented Reality on a C-Arm System: A Preclinical Assessment for Percutaneous Needle Localization

Purpose: To compare the navigational accuracy and radiation dose during needle localization of targets for augmented reality (AR) with and without motion compensation (MC) versus those for cone-beam computed tomography (CT) with real-time fluoroscopy navigation in a pig model. Materials and Methods: This study was approved by the Institutional Animal Care and Use Committee. Three operators each localized 15 targets (bone fragments) approximately 7 cm deep in the paraspinal muscles of nine Yorkshire pigs by using each of the three modalities (AR with and without MC and cone-beam CT with fluoroscopy). Target depth, accuracy (distance between needle tip and target), and radiation dose (dose-area product [DAP]) were recorded for each procedure. Correlation between accuracy and depth of target was assessed by using the Pearson correlation coefficient. Two-way analysis of variance was used for differentiating accuracy and DAPs across navigation techniques and operator backgrounds. Results: There was no correlation between depth of target and accuracy. There was no significant difference in accuracy between modalities (mean distance, 3.0 mm +/- 1.9 [standard deviation] for cone-beam CT with fluoroscopy, 2.5 mm +/- 2.0 for AR, and 3.2 mm +/- 2.7 for AR with MC [P = .33]). There was, however, a significant difference in fluoroscopy radiation dose (10.4 Gy.cm(2) +/- 10.6 for cone-beam CT fluoroscopy, 2.3 Gy.cm(2) 6 2.4 for AR, and 3.3 Gy.cm(2) +/- 4.6 for AR with MC [P < .05]) and therefore in total procedural radiation dose (20.5 Gy.cm(2) +/- 13.4 for cone-beam CT fluoroscopy, 12.6 Gy.cm(2) +/- 5.3 for AR, 13.6 Gy.cm(2) +/- 7.4 for AR with MC [P < .05]). Conclusion: Use of an AR C-arm system reduces radiation dose while maintaining navigational accuracy compared with cone-beam CT fluoroscopy during image-guided percutaneous needle placement in a pig model. (C) RSNA, 2016