A look at the interventional strategies used in the treatment of headache
By Lauren R. Natbony, MD, Assistant Professor of Neurology, Center for Headache and Facial Pain, The Mount Sinai Hospital, New York
Interventional headache management aims to stop or substantially reduce head and facial pain. Whereas acute or “rescue” treatment is meant to relieve a single headache attack, and preventative therapies target an overall reduction in headache frequency, interventional management can be both: acute and/or preventive. There are multiple intervention strategies used in headache, the most common of which are peripheral nerve blocks, sphenopalatine ganglion blocks and trigger point injections. While all patients may benefit from these procedures, they can be especially helpful for patients in whom standard medication therapy does not work, is not tolerated or is contraindicated.
Three approaches to interventional headache management
Peripheral Nerve Blocks
Peripheral nerve blocks are one of the most frequently used interventional treatments for headache. A nerve block consists of medication administered via a small-needle syringe injected in or near a nerve involved in headache. These nerves are located at the back of the skull (occipital nerves) as well as near the temples and above the eyebrows (trigeminal nerve branches). Medications used include a local anesthetic, for numbing, and occasionally a steroid, to reduce inflammation.
Nerve blocks work by effectively “shutting down” overactive pain signals. Parts of the head will become numb for several hours; however, benefits can last longer due to a decrease in pain signals being sent to the brain. A successful nerve block can last from several days to several weeks, and may be more effective with each subsequent injection. Nerve blocks can be helpful for many different types of headache including migraine, cluster headache, occipital neuralgia and cervicogenic headache.
There are few contraindications to nerve blocks: they are safe, well-tolerated and can even be used during pregnancy. Injections can be done every few weeks, depending on the recommendations from your healthcare provider. Some patients may be candidates for nerve ablation, which uses extreme cold or radiofrequency to disable pain signals. This method can treat the pain for a longer duration, usually around 6 months.
Sphenopalatine ganglion blocks
The sphenopalatine ganglion (SPG) is a bundle of nerve cells located behind the nose that is linked to the main nerve involved in headache, the trigeminal nerve. The SPG carries information about sensation, including pain, and by blocking the SPG with local anesthetics, pain can be reduced. The most common conditions treated by SPG blocks are cluster headaches and other trigeminal autonomic cephalalgias, trigeminal neuralgia and other facial pain syndromes, as well as migraine headaches.
There are now 3 devices on the market for performing SPG blocks that have been FDA approved. The devices work by placing a very thin plastic tube into the nose and delivering numbing medication in and around the SPG. This procedure is typically done in both nostrils and takes about 10-20 seconds, with results occurring anywhere from 15 minutes to a few hours later. Side effects, if they occur, are all temporary, and can include numbness in the throat, low blood pressure and nausea.
SPG blocks can be done every few weeks, depending on the recommendations from your healthcare provider. They can also be done as part of a preventative strategy, as there is evidence to suggest that SPG blocks done twice a week for six weeks can reduce the frequency and severity of chronic migraine.
Trigger Point Injections
Trigger points are areas in the muscle that are very irritable, tight, and when pressed, may produce a “twitch” within the affected muscle. When pressed, a trigger point may cause pain not only in the affected muscle, but also in distant areas in the head and neck. This phenomenon is called “referred pain.” Trigger points in the head, neck and shoulders are commonly present in patients with migraine, tension-type headache, post-traumatic headache, cervicogenic headache and other headache disorders.
A trigger point injection is a procedure where a medication, usually a local anesthetic, is injected into a painful muscle to provide relief. When medication is injected into a trigger point, pain relief should be felt not only in the injected muscle, but in the area(s) of referred pain as well. Immediately after the injection, patients may feel that the pain has resolved or lessened significantly. This improvement can last for weeks or longer. The injections can be repeated as needed. Trigger point injections are safe and well-tolerated, with the most common side effect being temporary pain at the injection site.
Interventional approaches are promising supplements to currently available headache therapies. Nerve blocks, sphenopalatine ganglion blocks and trigger point injections are relatively safe and well tolerated, and thus can be used for a wide array of patients. Discuss with your doctor whether these treatments may be appropriate for you.