Dual-Target SPG-Mandibular Neuromodulation for Post-Radiation Painful Trigeminal Neuropathy: A 7-Year Follow-up

Chronic facial neuropathic pain following surgical or radiation-induced trigeminal nerve damage presents significant therapeutic challenges.

We aim to demonstrate the effectiveness of combined SPG and V3 neuromodulation as a potential therapiutic measure for trigeminal neuropathy.

First, trial SPG neuromodulation was implanted. Based on significant decreaze in VAS score after trial period, the permanent SPG and, in addition, mandibular electrode (V3) were provided.

A 72-year-old male with diabetes mellitus and dyslipidemia presented to our pain clinic in 2017 with chronic facial pain. In 2008, he underwent left parotid gland tumor resection, chemotherapy and radiation therapy. Facial pain developed post-treatment and significantly worsened following left carotid artery stenting in 2015. Pain was localized to the left maxillary (V2) and mandibular (V3) divisions of the trigeminal nerve with constant burning pain (VAS 5/10) and superimposed electric shock-like attacks (VAS 8-9/10). After failure of multimodal pharmacological and interventional treatments, combined SPG and V3 peripheral nerve stimulation was performed. During interventional procedure, at first, permanent SPG neuromodulation and then, the mandibular electrode was introduced from the same incision. The patient achieved 90% pain reduction initially, with sustained benefit at 7-year follow-up despite some habituation.

Combined sphenopalatine ganglion and V3 neuromodulation represents a viable therapeutic option for refractory facial neuropathic pain, particularly in cases with multiterritorial involvement.