Long-Term Results of Deep Brain Stimulation of the Anterior Cingulate Cortex for Neuropathic Pain.

Abstract

Deep brain stimulation (DBS) of the anterior cingulate cortex (ACC) is a recent technique that has shown some promising short-term results in patients with chronic refractory neuropathic pain. Three years after the first case series, we assessed its efficacy on a larger cohort, with longer follow-up. Twenty-four patients (19 males; average age, 49.1 years) with neuropathic pain underwent bilateral ACC DBS. Patient-reported outcome measures were collected before and after surgery, using the Numerical Rating Scale (NRS), Short-Form 36 quality of life (SF-36), McGill Pain Questionnaire (MPQ), and EuroQol 5-domain quality of life (EQ-5D) questionnaire. Twenty-two patients after a trial week were fully internalized and 12 had a mean follow-up of 38.9 months. Six months after surgery the mean NRS score decreased from 8.0 to 4.27 (P= 0.004). There was a significant improvement in the MPQ (mean,-36%; P= 0.021) and EQ-5D score significantly decreased (mean,-21%; P= 0.036). The physical functioning domain of SF-36 was significantly improved (mean,+54.2%; P= 0.01). Furthermore, in 83% of these patients, at 6 months, NRS score was improved by 60% (P < 0.001) and MPQ decreased by 47% (P < 0.01). After 1 year, NRS score decreased by 43% (P < 0.01), EQ-5D was significantly reduced (mean,-30.8; P= 0.05) and significant improvements were also observed for different domains of the SF-36. At longer follow-ups, efficacy was sustained up to 42 months in some patients, with an NRS score as low as3. Follow-up results confirm that ACC DBS alleviates chronic neuropathic pain refractory to pharmacotherapy and improves quality of life in many patients.