Pterygopalatine ganglion (SPG)

The pterygopalatine ganglion (commonly known as the sphenopalatine ganglion, SPG) is the largest parasympathetic ganglion in the head, located in the pterygopalatine fossa beneath the maxillary nerve[1][7]. It receives presynaptic parasympathetic fibers (primarily from the greater petrosal nerve, a branch of the facial nerve), sympathetic fibers from the deep petrosal nerve, and sensory fibers from the maxillary nerve (V2). The SPG supplies the lacrimal glands, nasal mucosa, paranasal sinuses, pharynx, and palate, mediating secretomotor, vasodilatory, and sensory functions in these structures[1][7]. The SPG is a validated therapeutic target for intractable craniofacial pain, cluster headaches, migraines, trigeminal neuralgia, and various other pain and autonomic syndromes. Interventions include local anesthetic block, neurolysis, radiofrequency ablation, and neurostimulation. Therapeutic targeting of the SPG can relieve pain and autonomic symptoms, though long-term efficacy and safety vary by method[2][3][5][10].

Other names

Sphenopalatine ganglionMeckel's ganglionNasal ganglion

Blockade of parasympathetic and some sensory outflow to reduce pain transmission Neurolytic ablation for long-term pain relief Electrical stimulation to modulate pain pathways and autonomic activity