Postherpetic neuralgia (PHN) is a devastating disease with extraordinarily poor treatment outcomes. Both pulsed radiofrequency (PRF) and ozone have good effects on the treatment of the disease. However, whether PRF and ozone have a synergistic effect on PHN remains unclear. Therefore, this study aimed to assess the therapeutic effects of ozone alone and in combination with PRF in the treatment of PHN. Ninety-one patients with PHN were assigned into two groups: PRF combined with ozone (PRF + ozone group, n = 44) and ozone therapy alone (ozone group, n = 47). In PRF + ozone group, the high-voltage, long-duration PRF was applied to the target dorsal root ganglions. Then ozonated water (11.5 µg/mL) was injected through the inner cannula. In the ozone group, all other processes were the same as those in the PRF + ozone group apart from the electrical stimulation. The therapeutic efficacy was evaluated by visual analog scale and tactile sensation at pre-treatment and post-treatment 3, 6, and 12 months. Compared with pre-treatment data, the visual analog scale score was significantly decreased in both groups after treatment. Compared with the ozone group, the visual analog scale score was significantly decreased in the PRF + ozone group at 3, 6, and 12 months. Similarly, the tactile sensation was also significantly decreased at post-treatment when compared to pre-treatment. However, there were no statistical differences between the two groups. Regression analysis results showed that the history of diabetes mellitus and age had significant negative and positive effects, respectively, on the treatment results. To conclude, the administration of PRF + ozone and ozone therapy alone could both improve pain symptoms. Moreover, treatment effects and total efficacy rates tended to be higher for the combination of PRF and ozone than ozone alone. This conclusion was especially true for long-term therapeutic effects.
Keywords: dorsal root ganglions; Gasserian ganglion; neuromodulatory effects; ostherpetic neuralgia; ozone therapy; pulsed radiofrequency; synergistic effects; total efficacy rate; ultrasound-guided; visual analog scale.