Indications
Patients with chronic headaches experience debilitating headaches at least fifteen days out of every month. These headaches can be very severe and limit one’s ability to carry out the usual activities of daily living. Chronic headaches affect approximately 5% of the population. While there are many types of headaches, the most common include migraine headaches, cluster headaches, and headaches due to trigeminal neuralgia, tension, sinusitis, temporomandibular joint (TMJ) dysfunction, and head and neck cancer. Numerous medications are available to help manage the pain associated with headaches. These medications have worked with varying degrees of success, and some of them have side effects that cause patients to stop taking them. Other treatments have been performed which may or may not help with headache relief including massage, cognitive behavioral therapy, acupuncture, and botox injections.
A sphenopalatine ganglion (SPG) nerve block is an accepted, minimally invasive therapy for chronic headaches. A ganglion represents many nerves grouped together that send messages to other nerves. Some ganglia help control movement and some help with sensation including pain and temperature, while others help with both. The SPG is located in the back of the nasal cavity, outside of the brain, and as a result, is the only ganglion exposed to the environment. It has very close connections with many nerves, including the trigeminal nerve, which send signals to and from the brain controlling sensation, pain and certain movements. Many studies have demonstrated that stimulation of the SPG can cause debilitating chronic headaches. By disrupting the function of the nerves in the SPG, it is possible to reduce the facial pain and headaches experienced by many patients, leading to significant improvement in symptoms and quality of life. Studies have shown that this procedure has the potential to provide relief for chronic headache sufferers who do not respond to the typical and alternative treatments mentioned above.
Procedural Details
Although there are different approaches to blocking the SPG, the "needle-less" intranasal approach is the simplest, most common, and least risky. After an anesthetic spray is given into each nostril, you will be asked to lie down with your neck slightly extended. X-rays are used to guide a small (spaghetti sized) catheter into each nostril. A very small amount of contrast (x-ray dye) is injected to confirm adequate position of the catheter. This is then followed by the administration of concentrated xylocaine to block the SPG. The entire procedure takes 15-30 minutes and does not require sedation.
Results
Studies have shown that up to 80% of patients with chronic headaches will have significant improvement of their typical symptoms after an SPG block. Almost 2 out of 3 patients show complete or near complete resolution of symptoms within 24 hours of the procedure; many of these patients continue to have improvement one week after the procedure. 58% of patients report sustained improvement at one month and 50% at three months. The majority of the patients are able to decrease or stop their medications altogether. If significant relief is achieved, the procedure can be repeated and potentially lead to additional long term relief. Headaches related to allergies, muscle tension, or degenerative disc disease in the cervical spine are much less likely to respond long-term to the SPG block.
The risks and side effects of an intransnasal SPG block are few. A significant allergy to xylocaine and x-ray dye can occur but is rare. Infection and nosebleed (epistaxis) from nasal irritation is also very rare. You may experience a bitter taste from the medicine as well as a temporary numbness in the nose, mouth and throat from the xylocaine.