Ultrasound Guided Trigeminal Nerve Block

Ultrasound-guided trigeminal nerve block via the coronoid approach allows blockade of the maxillary andmandibular nerve as they pass through the pterygopalatine space. This technique is a simple, free of radiationor magnetization, safe, and effective percutaneous procedure in an office setting, that provides sustained painrelief in trigeminal neuralgia or atypical facial pain patients who have failed previous medical interventions. Thesimplicity and safety of this technique lend itself to the diagnosis and treatment of a variety of painfulconditions subserved by the maxillary and mandibular divisions of the trigeminal nerve.This technique is useful in the setting of acute pain secondary to trauma, pain of malignant origin, postsurgicalpain, dental pain, breakthrough pain of trigeminal neuralgia, atypical facial pain, trismus, and the pain of acuteherpes zoster. It can be used in the setting of chronic pain to help manage atypical facial pain includingtemporomandibular joint dysfunction and postherpetic neuralgia.During the procedure a linear transducer is placed directly in the transverse position over the coronoid notch.Under real-time ultrasound guidance, the needle is inserted just below the zygomatic arch directly in themiddle of the coronoid notch using an out-of-plane approach. The needle is advanced until it impinges on thelateral pterygoid plate. Then the needle is withdrawn slightly out of the periosteum. After careful aspiration iscarried out, injectant solution is slowly injected in incremental doses.The vascular nature of this anatomic region mandates care when injecting local anesthetics into the area. Thepatient must be observed carefully for signs of local anesthetic toxicity.