Postoperative Determination of Directional DBS Lead Orientation: A Comparison of CT-Based Software and Rotational
Paresh K Doshi1, Raj V Agarbattiwala2, Chandresh Karnavat3
1Stereotactic and Functional Neurosurgery Department, Jaslok Hospital and Research Center, Mumbai, India, pareshkd@gmail.com.
Introduction:
During evaluation of the Brainlab Elements™ software for postoperative determination of directional deep brain stimulation lead orientation, we noted a lack of published in vivo comparative agreement data. At the same time, prior reports have described substantial variability in implanted lead rotation angles, underscoring the need to verify software-based estimates. We therefore compared Brainlab Elements™ with 3D rotational fluoroscopy, analyzed using the "Iron Sights" method (ISM), by two independent observers.
Methods:
We prospectively analyzed 70 directional leads implanted at our center (2022-2024). Orientation was measured on postoperative rotational fluoroscopy by two independent observers and compared with postoperative CT analyzed in Brainlab Elements™. The agreement was evaluated using established reliability statistics.
Results:
Observers using the ISM produced highly consistent measurements, differing on average by <1° and rarely more than ±7°. Compared with CT-based analysis, the ISM showed good agreement, with differences typically within ±15°. These margins correspond to <1.5 mm displacement at 6-mm radial distance from the lead.
Conclusion:
Interobserver agreement using the ISM was excellent (ICC [2, 1] = 0.983). Brainlab Elements™ estimations (ICC [3, 1] = 0.864; limits of agreement ≈ ±15°) correlated well with the ISM.
