used ultrasound-guided platelet rich plasma nerve block to treat Intractable Postherpetic Neuralgia.

Postherpetic neuralgia (PHN) is a kind of pain caused by varicella zoster virus invading the human body and infecting the corresponding ganglia. The affected ganglia are inflamed or even necrotic, affecting the nerve endings, the dorsal horn of the spinal cord and the sensory nerve tissues below, and the course of the disease is more than one month or more. Most patients can avoid PHN by timely and effective treatment in the acute herpes zoster period. However, some patients with intractable postherpetic neuralgia fail to receive timely and effective pain control treatment in the early stage of the disease, and the current commonly used clinical treatment methods often fail to achieve effective treatment results. Such patients often have a long course of disease, which can last for three to five years or even longer, Nerve damage is also more serious. Long term pain has seriously affected the quality of life of such patients. Therefore, how to quickly and effectively control pain has become the diagnosis and treatment goal of such patients with intractable post herpetic neuralgia. Platelet rich plasma (PRP) was widely used in muscle and bone repair due to its function of promoting tissue repair in the early stage. Recently, it was found that PrP can also promote nerve repair. Therefore, in order to further explore the therapeutic effect of PRP on refractory PHN patients, our department used ultrasound-guided platelet rich plasma nerve block to treat Intractable PHN.

Inclusion Criteria:

• Meet the diagnostic criteria of PHN: have a history of acute herpes zoster, the pain lasts for more than half a year, and there is paroxysmal pain in the affected nerve distribution area;
• Preoperative visual analog scale (VAS) score ≥ 5;
• Those who can cooperate with the treatment;
• We agreed to inject platelet rich plasma into nerve block under the guidance of ultrasound, and signed the informed consent form.

Exclusion Criteria:

• Systemic infection or puncture local infection;
• Serious disturbance of cardiovascular and cerebrovascular function;
• Abnormal bleeding and coagulation function or complicated with blood system diseases;
• Mental disorders;
• Severe dysfunction of important organs in the body