Ultrasound-guided greater auricular nerve block is most commonly utilized in conjunction with lesser occipital nerve and auriculotemporal nerve block to provide complete surgical anesthesia and/or postoperative pain relief for the surgery of the external ear. As a stand-alone technique, ultrasoundguided greater auricular nerve block is useful in the diagnosis and treatment of painful conditions in areas subserved solely by the greater auricular nerve including greater auricular neuralgia, red ear syndrome, and pain secondary to acute herpes zoster and postherpetic neuralgia (Fig. 6.1). This technique can also be utilized to provide surgical anesthesia in the distribution of the greater auricular nerve for lesion removal and laceration repair as well as to aid in localization of the nerve for nerve graft harvesting.

The largest sensory branch of the cervical plexus, the greater auricular nerve, arises from fibers of the primary ventral ramus of the second and third cervical nerves (Fig. 6.2). At a point just inferior and lateral to the lesser occipital nerve, the greater auricular nerve pierces the cervical fascia and passes superiorly and forward and then curves around the sternocleidomastoid muscle. The greater auricular nerve then pierces the superficial cervical fascia to move more superiorly and superficially to provide cutaneous sensory innervation to both surfaces of the auricle, the external auditory canal, angle of the jaw, and the skin overlying a portion of the parotid gland (Figs. 6.3 and 6.4).

The patient is placed in the supine position with the head turned away from the side to be blocked. Five milliliters of local anesthetic is drawn up in a 10-mL sterile syringe, and 40 to 80 mg of depot steroid is added to the local anesthetic if there is thought to be an inflammatory component to the patient’s pain symptomatology.

The posterior border of the sternocleidomastoid muscle at the level of the cricoid notch is then identified, and the skin overlying the area is prepped with antiseptic solution. A high-frequency linear ultrasound transducer is then placed over the posterior border of the sternocleidomastoid muscle at the level of the cricoid in a transverse oblique position at essentially a right angle to the posterior border of the sternocleidomastoid muscle (Fig. 6.5). At this point, the greater auricular nerve will be visible twice in the same image and once in its position deep to the sternocleidomastoid muscle and then again in its superficial position as it curves back


around the more superficial surface of the muscle (Fig. 6.6). Ultrasound imaging will also help the practitioner identify the relationship of the carotid artery and jugular vein to the greater auricular nerve to help avoid inadvertent intravascular injection (Fig. 6.7). It is at this point that the greater auricular nerve is blocked utilizing an in-plane approach by advancing a 22-gauge, 1½-inch needle in proximity to the superficial portion of the nerve (Fig. 6.8). A paresthesia may be elicited, and the patient should be warned of such. After gentle aspiration, 2 mL of solution is injected under
real-time ultrasound imaging. The needle is removed and pressure is placed on the injection site to avoid hematoma or ecchymosis.