Severe immune rejection leading to refractory peri-electrode edema after DBS: a systematic review and one case report.

Deep brain stimulation (DBS) is a well-established therapy for advanced Parkinson’s disease (PD), yet peri-electrode edema remains a poorly characterized postoperative complication. We present a 51-year-old male with a 9-year history of PD who underwent bilateral subthalamic nucleus (STN)-DBS implantation. Postoperative imaging confirmed accurate electrode placement, and the patient was discharged without immediate complications. However, one week post-surgery, he developed right-sided neck stiffness and spontaneous seizures, followed by progressive right limb weakness and gait impairment. Magnetic resonance imaging (MRI) revealed extensive peri-electrode edema surrounding the right electrode, accompanied by cutaneous erythema and sleep disturbances. Despite aggressive treatment with dexamethasone, antiepileptics, and osmotic diuretics, the edema recurred repeatedly upon dose reduction. Ultimately, the DBS hardware was explanted due to refractory symptoms, with intraoperative findings of inflammatory exudate but no overt infection. This case highlights that peri-electrode edema, though often asymptomatic, may manifest with severe neurological sequelae requiring prolonged intervention. Furthermore, corticosteroid therapy, while effective in acute management, may fail to prevent recurrence in certain patients, necessitating hardware removal. In most cases, the edema resolves without the need for intervention. This case underscores that severe neurological sequelae may arise even after standard management, highlighting the need for individualized therapeutic strategies. Our study provides a comprehensive analysis of the etiological factors, clinical characteristics, and treatment modalities of this condition, offering critical insights to refine its diagnosis and management.