A Clinical Observation On The Therapeutic Effects Of Botulinum Toxin Type A In The Treatment Of Occipital Neuralgia

Background and Objective: Occipital neuralgia(ON)is a commonly an element of chronic headaches which is characterized by pain in the distribution of the greater and/or lesser occipital nerves and great ear nerves. The pain maybe unilateral or bilateral and it is typically accompanied by paresthesias in the distribution of the occipital nerves. It can not only be persistent, but also be paroxysmal attack. And it can be accompanied by the feeling unusual of the affected area, while the intermittent period can be completely normal. The distribution of the occipital nerves can be painful in the physical examination and the imaging results are always normal.The current treatments of ON include medication therapy, occipital nerve blocks, and surgical techniques. But the results are less than satisfactory for the limited efficacy and severe side effects. Recent studies demonstrate the obvious efficacy and slight side-effect of Botulinum Toxin Type A(BTX-A) in the treatment of other headache types.This study used BTX –A in the treatment of occipital neuralgia and observed the recent and forward clinical efficacy in order to add further evidence and clinical guidance for the BTX-A in treating ON.Methods: Twenty patients with occipital neuralgia were involved in this study. The inclusion criteria:(1) the pain in one side or both sides and located in the distribution of the greater and/or lesser occipital nerves and great ear nerves;(2) the type of pain is needle pain or dull pain;(3) the pain radiate from the occipital region to the frontal and temporal areas;(4) the nerves which are affected have tenderness or dull pain;(5) local block treatment can relief the pain;(6) imaging results can except intracranial diseases. BTX-A was injected into the occipital nerve distribution with three to six points. Subjects were instructed to report their daily pain level prior to the injection treatment, 2 weeks following therapy, 2 months following therapy and 6 months after the treatment on a visual analog pain score(VAS).The treatment response was classified as “recovery”(pain symptoms disappear entirely), “good response”(>75% improvement), “part response”(50%~75% improvement), no response(less than 50% improvment). SPSS 17.0 software was used for statistic analysis. Hypothesis testing methods used t test, and lower than 0.05 was taken as significant.Results: 1. During the period of follow up, the patients showed significant reduction for the severity of ON. Overall, 95% of subjects were responders, of which 10% were cured, 60% showed an over 75% improvement, and 25% showed a 50% to 75% improvement. The VAS was 7.50±1.27 before the BTX-A treatment. The score decreased to 2.80±1.23, 1.95±1.73, 3.25±1.80 at two weeks, two months and six months after the therapy. The effects of VAS in the treatment of ON was considered as statistically significant(P<0.05). 2. There were not severe adverse complications in all of the patients except local pain.Conclusion:1. BTX-A is effective in the treatment of ON.2. The effects of BTX-A can sustain 6 months.3. There were not severe complications during the treatment and the period of follow up.