Utilizing the Flexibility of Directional Deep Brain Stimulation Intraoperatively (if Needed) to Minimize Microelectrode Lead Repositioning

This index case report describes the intraoperative use of an eight-contact directional deep brain stimulation (DBS) lead to avoid adjustment and repeat microelectrode passes after the initial pass elicited side-effects that suggested a slightly anteriorly placed lead. While targeting the subthalamic nucleus (STN), intraoperative microelectrode recording (MER) confirmed that lead positioning and macrostimulation resulted in response at 1 mA but sustained dysarthria at 2 mA. This suggested a slightly anteriorly located electrode. The patient was becoming anxious, so instead of lead adjustment, an eight-contact directional DBS lead was placed to take advantage of the directional contacts, noting that a repeat pass could always then be performed. Segmented contact 11C showed symptom response at 0.5 mA and side-effect at 4 mA, resulting in a 3.5 mA therapeutic window. Though no substitute for an accurately placed lead, this result suggests that the flexibility of directional stimulation could be considered in the intraoperative setting.