Sphenopalatine ganglion block is a procedure in which a local anesthetic is delivered to the sphenopalatine ganglion (SPG)—a group of nerve cells located behind the nose. It is used to treat headache disorders, such as:
- Trigeminal neuralgia
- Migraine
- Cluster headache
- Paroxysmal hemicranias
- Trigeminal neuopathy
The sphenopalatine ganglion contains sensory nerves, which carry sensations such as pain, and autonomic nerves, which control functions such as tear formation and nasal congestion. The SPG is connected to the brainstem and the coverings of the brain called the meninges by the trigeminal nerve, which is the main nerve involved in headache disorders.
The anesthetic can be delivered to the SPG by applying it to cotton swabs and placing them into the back of the nose. It can also be given by an injection into the cheek, but this technique usually requires an X-ray to verify correct placement of the needle. A newer technique involves delivering the anesthetic through a thin plastic tube that is placed in the nose. This method is less invasive than an injection.
The local anesthetic works by blocking or reducing pain signals carried by the nerve cells in the sphenopalatine ganglion. The duration of pain relief vares greatly, with some people experiencing minimal pain relief and others seeing improvement for days or months. The procedure can be repeated as necessary.