Introduction: Intracranial air (ICA) potentially influences the accuracy and efficacy of deep brain stimulation (DBS), but the influence of ICA on distal contact position is less well-studied. In this study, we analyzed several measures of electrode movement and clinical outcomes with ICA volume.
Methods: Prospective evaluation of 73 consecutive patients who underwent bilateral subthalamic nucleus DBS for Parkinson’s disease. Immediate and follow-up CTs were analyzed for ICA, lead displacement, and targeting accuracy. Measures of clinical outcomes were also assessed.
Results: For 146 leads, mean distal contact deviation was 1.2 ± 0.7mm and mean bowing of the proximal lead was 2.8 ± 1.4mm. Mean targeting error was 2.0 ± 1.2mm. Average ICA volume was 21.3 ± 13.7cm3, with significant correlation between ICA volume and proximal bowing of the lead (p=0.01), but not distal contact deviation or targeting error. MDS-UPDRS scores and LED were not correlated to ICA. ICA extremes also showed no difference in these parameters.
Conclusions: Though the proximal DBS leads bends in association with ICA, movement of the distal tip and targeting error do not correlate with ICA. This finding is maintained when analyzing extremes of ICA. Additionally, volume of ICA does not correlate with clinical outcomes.
Patient Care: This research will help surgeons understand an important factor in electrode placement during DBS surgery for Parkinson's disease and will contribute to improved surgical planning.
Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe the importance of intracranial air on electrode positioning, 2) Describe the impact of intracranial air on measures of functional outcome, 3) Describe the difference in position of the proximal versus distal electrode relative to volume of intracranial air.
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