Split cannula method for accurate placement of an electrode for deep brain stimulation: Technical note

OBJECTIVE: We describe a 'split cannula method' for accurate placement of a deep brain stimulation electrode. This method eliminates the risk of displacement of the electrode when withdrawing the outer guide cannula. METHOD: A separate short guide cannula is covered over the distal part of a long cannula for microrecording or macrostimulation. After confirmation of the stimulation point, the short cannula is fixed with an accessory-holding device and the long cannula is pulled out. The electrode for deep brain stimulation is inserted through the short cannula. Because this cannula is much shorter than the electrode, securing the stimulation electrode at any withdrawal stage of the outer guide cannula is always possible. RESULTS AND CONCLUSION: With this simple method, we experienced no displacement of the stimulation point during stereotactic insertion of a deep brain stimulation electrode. This method can be easily adapted to any stereotactic frame.