Sphenopalatine Ganglion Blocks

The sphenopalatine ganglion (SPG) is also known as the pterygopalatine ganglion. It is a parasympathetic ganglion but also has connections to sympathetic, sensory, and motor fibers. The SPG has been a target for pain management since the early 1900s after being described by Sluder. SPG blockade has been proposed to treat a variety from different headache diagnoses, facial pain, neuropathic pain, and even myofascial pain. The approaches range from intranasal, infrazygomatic, to transnasal using a multitude of imaging modalities including fluoroscopy, computed tomography (CT), and ultrasound. Cocaine, lidocaine, bupivacaine, ropivacaine, radiofrequency thermocoagulation (RFTC), and pulsed radiofrequency (PRF) treatment have all been used to modulate the SPG. Despite moderate quality evidence, there remains only weak recommendations for SPG modulation.