EP 53. Determining the orientation of directional deep brain stimulation leads from computed tomography data

Introduction Directional deep brain stimulation (DBS) leads designed to preferentially stimulate structures at specific orientations relative to the DBS lead have recently shown promise during acute testing in patients ( [Contarino et al., 2014] , [Pollo et al., 2014] ). However, sustained improvement of DBS therapy using directional leads depends on identification of the orientation of these leads relative to brain structures of interest. The aim of this work is develop a method for reliable and automated identification of the orientation of directional leads from computed tomography (CT) data. Methods To determine the orientation of directional leads (Boston Scientific) from CT data, an algorithm for automated directional lead orientation detection was developed utilizing methods from image processing and registration methods. Clinical grade CT scans were acquired of directional lead phantoms with specific pre-determined orientation of the leads and the performance of the automated directional lead orientation detection algorithm was tested on these scans using cross-validation techniques. Results The algorithm determined the directional lead orientations with a median accuracy of less than 10° across a wide range of scan and algorithm parameters. Conclusions Post-operative CT imaging can be used to detect the orientation of a directional lead with an accuracy better than 10° with standard resolution CT scans, provided slice thickness and slice overlaps are chosen appropriately.