Cervical Sympathetic Blockade for Psychogenic Nonepileptic Seizures Associated With Post-traumatic Stress Disorder: A Case Report and Neurobiological Framework.

Psychogenic nonepileptic seizures (PNES), also termed functional seizures, are episodes that resemble epileptic seizures but occur without the abnormal ictal electrical activity characteristic of epilepsy. PNES is frequently associated with trauma exposure, post-traumatic stress disorder (PTSD), and abnormalities in autonomic regulation. Emerging evidence suggests that altered interactions among limbic, autonomic, and motor networks may contribute to symptom generation. Cervical sympathetic blockade (CSB), including stellate ganglion block techniques, has been investigated as an intervention for PTSD through modulation of sympathetic activity; however, CSB has not been established as a treatment for PNES. This case report describes an unexpected and subsequently reproducible reduction in PNES following CSB performed for severe, treatment-refractory PTSD, and considers a possible relationship between sympathetic modulation and trauma-associated functional seizures. A 27-year-old woman with severe PTSD and approximately 30 seizure-like or syncopal episodes per day was referred for CSB because of persistent PTSD symptoms despite prior conventional treatment. PNES was not the primary indication for the procedure. Ultrasound-guided CSB was performed at the C6 and C4 cervical sympathetic chain levels using 0.5% bupivacaine. Bilateral procedures were staged 24 hours apart as a safety precaution. Following CSB, PTSD symptoms improved, while the reduction in PNES occurred on a more delayed time course. Seizure-like and syncopal episodes progressively decreased and ultimately ceased approximately two months after treatment. The patient subsequently regained functional independence. Approximately one year later, following recurrence of symptoms and repeat CSB, a similar delayed pattern of seizure reduction and elimination was observed again. No major procedural complications occurred. The delayed but reproducible reduction and cessation of PNES following two separate courses of CSB suggests a possible association between cervical sympathetic modulation and functional seizure activity in a patient with severe trauma-related autonomic dysregulation. The mechanism is unknown, and the delayed response differs from the more rapid symptomatic improvement commonly reported following sympathetic blockade for PTSD. Potential downstream autonomic or neuroimmune effects may warrant investigation. This single-patient observation does not establish causality or support CSB as an established treatment for PNES, but it is hypothesis-generating and supports further prospective study of sympathetic modulation in carefully characterized patients with trauma-associated functional seizures.