Many potential chronic headache patients have asked if they are not surgical candidates because they have not responded to Botox® in the past. The answer is, “Not necessarily.” and the reason is because it depends on how and in what doses the Botox was used. The primary way in which Botox® is used by most neurologists and pain management physicians is based upon the PREEMPT protocol (see attached). It calls for using 155 units over 31 injection sites every three months in an effort to reduce the symptoms associated with chronic migraine headaches. There are several problems with this approach.
First and most obvious is that the studies themselves were funded by Allergan, the makers of Botox®. Moreover, many of the study authors receive honoraria, speaking fees and consultancy fees from Allergan. While these issues are explicitly stated in the papers themselves, they are nevertheless conflicts of interest. Second, some of the results are not as exciting as the papers would suggest. For example, over the 24 week treatment period, the reported decrease in frequency of headache days was 8.4 in the Botox® group and 6.6 in the placebo group. In other words if you were injected with Botox® according to this protocol, over a 6-month period you would have had 1.8 fewer headache days than if you were injected with saline! And that assumes you actually responded to the Botox® and had no adverse effects. While these numbers were statistically significant, it is a perfect example of the difference between statistical significance and clinical significance. Stated differently, would you as a patient be willing to be injected 62 times (31 times every 3 months) for 1.8 fewer headache days? Maybe or maybe not, but hardly a compelling case. Third, the results of these studies demonstrate a very high placebo response rate that the authors do not fully explain. Fourth, if you think about it, injecting Botox® in a shotgun-like approach (i.e. in 31 different places) will certainly relax some muscles leading perhaps to some relief of symptoms. But the question then becomes, “Which of the 31 injections was responsible for that effect or were all or some of them necessary?” This approach is akin to going to the ER with abdominal pain and being given morphine via an IV. Would you feel better? Of course you would, but now that the medication is circulating all over the place, was the pain the result of a simple GI bug or a burst appendix? You have no idea. Botox® used according to the PREEMPT protocol tells you nothing about the cause of the problem and is therefore used as a treatment which you must continue with in perpetuity.
In order to assess whether or not you would be a candidate for surgery to treat occipital neuralgia with Botox®, it should be injected focally around the muscles that are compressing (i.e. pinching) the nerves causing the problem. If successful, the nerves which you have chemically decompressed with Botox® are the nerves that need to be treated with surgical decompression. The overall doses used are much less than 155 units, the injection sites are far fewer and the results are often more effective. I would not operate on a person who got as little benefit as the patients in the PREEMPT studies. I look for at least a 50% reduction in the frequency, duration or severity of headaches in order to make that determination. In addition, if you think about it, the Botox® is being used as a diagnostic test, not a treatment method. If it works to the degree noted above, you don’t need any more Botox®, you need surgery to hopefully give you the same level of relief on a permanent basis without the need for any more injections. So if you’ve failed treatment with Botox® in the past, there is still hope that surgical decompression might be an option for you.