Directional Deep Brain Stimulation Lead Rotation in the Early Postoperative Period.

BACKGROUND AND OBJECTIVES

Directional deep brain stimulation (DBS) enables treatment optimization by current steering using segmented leads. Identification of the lead's rotational orientation is critical to guide programming decisions. Orientation is often assessed during or immediately after implant, but the degree of lead rotation in the following weeks is not well appreciated. Our objective was to measure the degree of DBS lead rotational orientation changes within the first few weeks after surgery.

METHODS

We retrospectively reviewed the clinical records of patients who were implanted with segmented DBS leads at our institution. All included patients had at least 1 immediate postoperative computed tomography (CT) (CT1) and another CT at least 1 week later (CT2). We assessed lead rotational orientation angles on CT1 and CT2 and calculated the degrees of rotation change between the scans. We also assessed for any effect of the time interval between scans by calculating the correlation between CT1-CT2 latency and degrees of lead rotation.

RESULTS

We assessed a total of 75 DBS lead orientations for 38 patients. The average change in lead orientation between CT1 and CT2 was 8.6° (median = 2.9°, range = 0.11-168.2°). Only 8 percent of patients (3/38) were found to have a significant change in orientation (>30°); however, when it occurred, it occurred bilaterally. There was no correlation between CT1-CT2 latency and lead rotation (r(74) = 0.04, = .73).

CONCLUSION

Our study finds that changes in lead orientation occurring over the first few weeks after surgery are rare. Thus, for most patients, the immediate postoperative CT is adequate for determining the orientation angles for clinical programming. However, if programming is found to be difficult, a repeat CT scan could be beneficial for a minority of patients.