Background: Neuroimaging evidences and previous successful case series of cingulotomy for cancer pain have disclosed the key-role of the dorsal anterior cingulate cortex (ACC) in the generation of the empathic and affective dimension of pain. The aim of this study is to assess the effectiveness and safety of ACC neuromodulation for the treatment of the thalamic pain syndrome (TPS), a chronic neuropathic disease often complicated by severe affective and emotional distress in the long term.
Method: From January 2015 to April 2017, 5 patients with pure drug-refractory TPS underwent ACC deep brain stimulation (DBS) at our institution. Quantitative assessment of pain and health-related quality of life were performed 1 day before surgery and postoperatively at 6 and 18 months by using the numeric rating scale (NRS), the 36-item short-form health survey (SF-36), and the McGill pain and the EuroQol5-domain questionnaires.
Results: Mean age at surgery was 56.2 years (range, 47-66). NRS score improved by 37.9% at 6 months (range, - 22.2 to - 80%) and by 35% at 18 months (range, - 11.1 to - 80%). At the last follow-up, one patient reported a relevant pain reduction (NRS 2), only complaining of mild pain poorly interfering with activities of daily living. Concomitant improvements in the McGill and EuroQol5-domain pain questionnaires, SF-36 total and sub-item scores were also noticed at each follow-up. No surgical or stimulation-related complications occurred during the study period.
Conclusions: ACC DBS may be a safe and promising surgical option to alleviate discomfort and improve the overall quality of life in a patient affected by drug-resistant TPS. Further prospective, larger, and randomized studies are needed to validate these findings.
Keywords: Deep brain stimulation; Dejerine-Roussy syndrome; Neuropathic pain; Thalamic pain syndrome.