While we wish it never happened, an infrequent occurrence following migraine surgery is the return of headache pain. Just like any surgical procedure, migraine operations do have their rare failures, and in the case of migraine surgery, the failure rate is, fortunately, less than 10%. If you have a presence on social media, you may find that those who have had pain recur after surgery speak loudly and often. We would assume that the other 90% of patients with relief following their operations have moved on and don’t spend so much time on migraine forums anymore.
Why Migraine Surgery Might Be Unsuccessful
So if about one in ten patients don’t have a reduction of their pain, what happens? There have not been a lot of studies into this issue, likely because there are so few patients who have an unsuccessful outcome. But I feel that these non-responders, or patients who recur, fall into one of the following categories.
1) Patients who were not good candidates in the first place
In my practice, as in most migraine headache surgery practices, I perform my own nerve blocks to confirm that a patient’s pain is truly from a peripheral nerve entrapment. In some practices, however, referrals are obtained from neurologists or pain doctors who have done the injections, and in some cases, I would think that a marginal reaction to the injections could be turned into a referral and subsequent surgery that might not work if the pain was really originating from somewhere else. In my office, I want to see a true and not vague reduction in pain as a marker that the migraine patient will respond to migraine surgery.
2) Incomplete nerve release
When performing the microvascular techniques required for release of the nerve tissue some doctors may miss or incompletely release a particular structure that is causing nerve compression. I recently read one major study from 5 years ago where blood vessels next to the nerves in the forehead were retained in the operation, and this is not something we would consider doing now- we now know that vascular compression is a frequent cause of nerve inflammation and migraine pain, and so blood vessels next to nerves are now ligated as part of contemporary migraine surgery operations.
3) Scar tissue and neuroma
Even after successful and complete nerve decompression surgery, scar tissue can develop. This is the case with any surgery, and for example, a small number of patients who have abdominal surgery later get bowel obstruction from scar tissue in the abdomen. Such is the same with in cases in migraine surgery. If a muscle around a nerve is released, allowing decompression of that nerve, the healing process may involve some degree of scar tissue in the muscle that itself provides nerve compression following healing from the operation. Alternatively, scar tissue of the nerve itself, called a neuroma, may form following surgery. Here the nerve itself or the connective tissue around the nerve (called the sheath) may scar causing tethering or direct compression of the nerve. In these cases, pain recurs some time following the surgery as the scarring develops.
Migraine Surgery Revision
In two of the above cases, revision of a failed migraine surgery can be beneficial.
In situation #1 above, the patient was not a good candidate for the surgery in the first place- this is unlikely to change. Proper screening with injections can again prove that these patients should not have had migraine surgery and thus should not have migraine revision.
In situation #2, some structure remains that is persistently causing nerve compression and migraine pain. These patients often respond very well to a screening nerve block and then migraine surgery revision, also called “secondary surgery.” Exploration of the nerves in question will show blood vessels, muscle, connective tissue or bone that has not been adequately released, and completion of the release during the secondary surgery should fix the problem.
In situation #3, secondary revision migraine surgery can again be the answer. Exploration of the problematic nerves in this case will show an are that has excessive scar tissue, or we can find a scar in the nerve itself- a neuroma- which needs to be removed. Freeing of the nerve from the neuroma or other problematic scar should relieve the patient’s migraine pain once again.
I have been fortunate enough to see patients from only the latter two categories in my practice, and I am happy to say I have never seen a migraine surgery patient who was operated upon who did not have an indication for migraine surgery. While I have never done a revision of my own migraine surgery operations, I have performed secondary revision migraine surgery on patients from other surgeons with both scar tissue as well as incomplete nerve release. It is important for patients to know that even if there is a recurrence of migraine pain after migraine surgery, there may still be opportunities for migraine relief.
I tell all of my migraine surgery patients that there is a small chance that the operation is unsuccessful, and if that is the case a revision may be necessary. All surgeons of all kinds do that (or at least should do that.) I hope that if you have come across this blog and have had migraine surgery elsewhere, you consider at least seeing your surgeon or another surgeon to discuss your options. There may still be light at the end of your tunnel. Contact Migraine Surgery Specialty Center to learn more!
