Transnasal Versus Suprazygomatic SPG Block in Persistant Idiopathic Facial Pain

The transnasal approach to the sphenopalatine ganglion block allows for non-invasive access to the sphenopalatine ganglion, which is located deep in the nasopharynx in a recess posterior to the middle turbinate. A long cotton swab is inserted posterior to the nasopharynx until it is properly seated, and 2 mL of 2% lidocaine is injected through the outer end of the swab and left for 30 minutes. Patients are monitored for any potential complications or adverse effects throughout the procedure and for a period of time afterwards.

The ultrasound transducer is placed in the infrazygomatic area, above the maxilla, at approximately a 45 cephalad angle. With this transducer position, the ptrigopalatine fossa, bounded anteriorly by the maxilla and posteriorly by the pterygoid process, is visualized. A 25 gauge spinal needle is inserted 1 to 1.5 cm above the zygomatic arch and posterior to the posterior orbital rim and advanced through an out-of-plane approach to reach the pterigolapalatine fossa. After the aspiration test, 3 mL of 2% lidocaine is injected and the spread of the drug is monitored by ultrasound. Patients are monitored for possible side effects and complications.