Autologous fat grafting to the paravertebral space seems to prevent the postherpetic neuralgia-A single-arm pilot study.

Introduction: Postherpetic neuralgia (PHN) is one of the most common complications of Herpes zoster (HZ), yet the mechanism and the treatment for PHN remains elusive. We first performed this feasibility study to verify the safety and efficiency of autologous fat grafting into the paravertebral space in early HZ to prevent PHN.

Methods: Patients suffering from HZ with a rash in chest, back, or abdomen were arranged for autologous fat grafting to the paravertebral space. The primary endpoint was the incidence of PHN, which was defined as persistence pain in the affected dermal area in 12 weeks after fat grafting. Secondary endpoints including patient-reported changes in pain intensity, assessed pain threshold and the quality of life during follow-ups.

Results: Eight patients accept the intervention and completed all follow-ups. Most patients report immediate pain relief after injection, one patient has a mild to moderate dizzy symptom after injection. No other short- or long-term adverse events occurred. For primary outcome, all patients have a timely reduced pain intensity, with no PHN events occurred, as all patients report pain intensity ≤3 in the VAS scale in 3 months after treatment. For electrical pain threshold, we identify that fat grafting differentially increases sensation and pain threshold in HZ area and healthy skin of patients. Besides, our results indicate significant improvement in patients' life quality decrease in analgesic consumption.

Discussion: Autologous fat transplantation to the paravertebral space is a safe and feasible technique in preventing PHN from HZ in a rash. Further randomized controlled trial to investigate the actual long-term benefice of autologous fat grafting to the paravertebral space in preventing PHN is needed.

Trial Registration: ChiCTR, (ChiCTR1900025416); registered August 26, 2019.