Chronic migraine (CM) is a disabling disease that causes serious physical and emotional consequences. Previous studies had suggested the efficacy of stellate ganglion block (SGB) with lidocaine in the treatment of CM. However, the side effects related to repeated procedures limit its applications. Platelet-rich plasma (PRP) as an intervention treatment for chronic pain, has shown promising results to alleviate headache within the distribution range of the greater occipital nerve after trauma. So far, there has not been any report on PRP combined with lidocaine acting on SGB for CM. the investigators will conduct this multicenter, prospective, observational, propensity score matching, cohort, and assessor-blinded study to evaluate the efficacy and safety of lidocaine combined PRP acting on SGB versus lidocaine alone acting on SGB in patients with CM
