High-Voltage Long-Duration Pulsed Radiofrequency Combined With Liposomal Bupivacaine Subcutaneous Block for Herpes Zoster-Associated Neuralgia

High-Voltage Long-Duration Pulsed Radiofrequency Combined With Liposomal Bupivacaine Subcutaneous Block for Herpes Zoster-Associated Neuralgia

Research Objectives Background and Significance: Zoster-associated neuralgia (ZAN) refers to neuropathic pain experienced by herpes zoster (HZ) patients before, during, and after rash resolution, characterized by paroxysmal, lightning-like, or knife-like sensations. Postherpetic neuralgia (PHN), a common type of chronic pain, is often accompanied by physical-psychological impairments, social dysfunction, and anxiety-depression. While high-voltage long-term pulsed radiofrequency (HL-PRF) has become a conventional treatment for ZAN, it is limited by residual postoperative localized pain and suboptimal efficacy for refractory cases. Liposomal bupivacaine (LB), a sustained-release analgesic providing up to 72 hours of pain relief, offers potential for combined subcutaneous injection to enhance symptomatic control.

Study Process:

This clinical study focuses on evaluating the efficacy of HL-PRF combined with LB subcutaneous injection in treating ZAN. The trial will be conducted from December 16, 2024, to December 14, 2026, with an anticipated enrollment of 92 participants. Patients will be randomized into two groups:

HL-PRF group: Under CT-guided localization, high-voltage pulsed radiofrequency (HL-PRF) therapy was precisely delivered to the pathologically compromised dorsal root ganglion (DRG).

HL-PRF+LB group: HL-PRF treatment followed by LB subcutaneous injection at the painful lesion site 2 hours post-procedure.

Clinical data will be collected preoperatively, and inflammatory factors will be assessed on the first postoperative day. Follow-up evaluations via telephone will occur at 1 week, 1 month, 3 months, and 6 months postoperatively. By analyzing changes in observed indicators before and after treatment, this study aims to determine the clinical efficacy of combining HL-PRF with LB subcutaneous injection for ZAN.

Inclusion Criteria:

Patients diagnosed with zoster-associated neuralgia (ZAN) who meet ALL of the following conditions:

• Voluntarily provided written informed consent.
• Inadequate response to pharmacological or other non-surgical therapies OR intolerable drug-related adverse effects.
• Herpes zoster (HZ) lesions involving cranial/cervicocephalic, cervical, thoracic, or lumbar dermatomes.
• Moderate-to-severe pain intensity, defined as a Numerical Rating Scale (NRS) score ≥4 at baseline.
• Aged between 40 and 85 years.
• Body weight: Male ≥50 kg; female ≥45 kg.

Exclusion Criteria:

• Severe cardiovascular diseases or life-threatening arrhythmias (e.g., heart failure, third-degree atrioventricular block without pacemaker implantation).
• Contraindications to minimally invasive interventions (e.g., coagulation disorders, active infections).
• Allergy to local anesthetics or lipid emulsions; Severe dysfunction of vital organs (cardiac, pulmonary, hepatic, or renal) rendering the patient unfit for the procedure.
• Severe endocrine disorders or long-term use of corticosteroids/immunosuppressive agents.
• Cognitive impairment or inability to cooperate with treatment protocols.
• Prior history of neuromodulation therapies (e.g., spinal cord stimulation or pulsed radiofrequency (PRF) treatment).