Evaluation of preoperative efficacy of levodopa in subthalamic deep brain stimulation

Withdrawal of levodopa (L-dopa) the night before subthalamic nucleus-deep brain stimulation (STN-DBS) procedures have been a standard practice, although some patients experienced severe withdrawal symptoms. In this cohort study, we investigated the effects of continuing preoperative L-dopa therapy on intraoperative microelectrode recording (MER), intraoperative cooperation and the clinical outcome for deep brain stimulation (DBS) which was performed under local anesthesia.

The study included 99 patients with Parkinson's disease who were treated with bilateral STN-DBS between October 2014 and August 2018. The patients were followed for 12 months postoperatively and divided into "on-medication" and "off-medication" groups. The length of MER recordings, the number of microelectrode tracks, intraoperation cooperation, operation duration, and clinical outcomes were compared between the two groups.

The length of MER recording was longer in the "on-medication" group in both the left and right subthalamic nucleus (STN; P<0.001 and P=0.007, respectively). The unified Parkinson's disease rating scale (UPDRS) motor score indicated better improvement in the "on-medication" group at postoperative one month, six months and twelve months (P=0.045, P=0.034 and P=0.001 respectively). Patients in "on-medication" group could cooperate better with a shorter operation duration (177.9 vs. 195 min, P=0.038). Reduction in L-dopa equivalent dose (LED) and improvement of Hoehn-Yahr scale were comparable between the two groups during the follow-up period.

The continuation of L-dopa therapy prior to DBS procedures had no impediment on MER and can contribute to reducing the duration of operation, and benefit the electrode insertion, as well as the clinical outcomes.