gms | German Medical Science

Objective: Peripheral nerve field stimulation (PNFS) emerged during the last decades as an effective treatment option for chronic pain refractory to conservative treatment. In contrast to other neuromodulation methods which stimulate the main nerve trunk, PNFS electrodes are placed subcutaneously to stimulate the small nervous endings in the region of the affected nerves. This method is particularly useful for targeting smaller and well-defined pain areas like the facial region. We aimed to report on the outcome of chronic PNFS in the craniofacial region for migraine, occipital neuralgia, atypical facial pain, atypical trigeminal neuralgia or trigeminal neuropathy.

Methods: We retrospectively analysed the records of patients who underwent subcutaneous implantation of electrodes during the last two years in the craniofacial area at our department. The reduction of pain through stimulation was measured with the numeric rating scale (NRS) preoperatively and postoperatively at different time-points.

Results: Eleven patients were included in this study. Patients had a mean age of 63.6 years (range 44-75) at the time of the implantation. One patient was diagnosed with chronic migraine, one patient with occipital neuralgia, three patients with atypical facial pain, four patients with atypical trigeminal neuralgia and two with trigeminal neuropathy. The preoperative mean pain intensity using the NRS was 8.0/10 points (SD±0.77), one week after the procedure, it was 2.8/10 points (SD±3.03) and at maximum follow-up (mean 9.33 months SD±4.88), was 5.0/10 points (SD±2.98). A significant pain reduction was documented in both time periods, one week after the procedure (p<0.001) and at maximum follow-up (p<0.01), compared to preoperative scores. Electrodes were explanted within the first month after surgery in two patients who did not significantly benefit from PNFS. One electrode in one patient was explanted after 7 months of stimulation due to a local infection. No further complications were documented.

Conclusion: PNFS can be an effective and safe alternative for patients with chronic pain in the craniofacial area refractory to conservative therapy methods.