The face is among the most common anatomical sites for the utilization of regional nerve blocks. Direct infiltration into delicate facial structures can be very painful, and may distort the local anatomy, thus preventing proper comestic repair of facial lacerations.
The supraorbital nerve exits the supraorbital notch and branches cephalad into medial and lateral branches supplying the forehead and anterior scalp. The supratrochlear nerve supplies the midforehead and lies under the medial 1 cm of the eyebrow. The infratrochlear nerve exits the orbit superior to the medial canthus and travels inferiorly, supplying the medial eyelid, lateral nose superior to the medial canthus, medial conjunctiva and lacrimal apparatus.
Technique
These nerves can be blocked with a single injection along the supraorbital rim from lateral to medial. The landmark for this injection is the supraorbital notch, located on the superior medial orbital rim above the medial limbus. The nondominant hand marks the supraobital notch and the needle is inserted into the lateral edge of the middle third of the eyebrow and advanced to just medial to the medial canthus while aspirating and injecting 2 cc of anesthetic (11, 12).
Territory of the infraorbital nerve (maxillary branch of the trigeminal nerve) includes the cheek, upper lip, eyelid, and lateral aspect of the nose. The intraorbital nerve exits the infraorbital foramen approximately 1 cm below the inferior orbital ridge, palpable with a finger, along on a vertical line from the medial limbus of the eye. The foramen can be palpated with a finger tip rolled over the inferior orbital rim.
Technique
This block can be performed intraorally or transcutaneouly; the intraoral approach seems more comfortable for many patients, shields them from viewing of the needle, and is less likely to allow the needle to pass directly into the infraorbital foramen. For the intraoral technique, the third finger of the nodominant hand is placed over the infraorbital foramen, while the index finger and thumb are used to lift the upper lip. The needle is positioned over the canine tooth and inserted at the at the gingival buccal sulcus. While aspirating, the needle is advanced towards the finger marking the foramen, and 2 cc of anesthetic are injected.
Nose
Distribution
Cartalaginous dorsum and tip of nose.
Anatomy
The nose is supplied by both the ophthalmic (V1) and maxillary (V2) branches of the trigeminal nerve. The majority of the external nose is supplied by the dorsal (external) nasal nerve. This nerve sits in the groove within the nasal cavity and emerges at the lower border of the nasal bone 6-10 mm from the midline.
Technique
Nasal mucosa is anesthesized with topical spray or gel. For the external nose, dorsal nasal nerve block is preferable to painful injection of the tip of the nose. Using the nondominant thumb on one side of the nose and index finger on the other, palpate the end of the firm nasal bone at its junction with the mobile upper lateral cartilage. Insert the needle 6-10 mm off the midline and inject 1-2 cc of anesthetic. Repeat the block on the other side. Alternatively, both nerves may be accessed with a single injection site in the midline by advancing the needle inferior laterally to each side (11, 12).
Nasal Fracture Reduction
Reduction of simple nasal fractures under local anesthesia can be achieved using percutaneous or topical anesthesia or a combination of both. A study by Jones and Nandapalan (13) showed that use of intranasal cocaine with topical anesthetic (EMLA cream or AMETOP gel) on the external nose resulted in a less painful reduction than intranasal cocaine plus local infiltration over the bony dorsum of the nose (blocking the infratrochlear, infraorbital and dorsal nasal nerves). Use of intranasal cocaine and a topical agent such as EMLA can be an effective and well-tolerated technique anesthesia for simple nasal fracture reduction.
Lower Lip and Chin
Distribution
Lower lip and chin
Anatomy
The mental nerve (V3) leaves the mandible through the mental foramen in the midpupillary line approximately 1 cm inferior to apex of the second bicuspid apex.
Technique
An intraoral technique is well tolerated and more reliably blocks all fascicles of the nerve (12). When the lower lip is retracted with the nondominant hand, the mental nerve is visible are palpable in the majority of patients. The needle is inserts 5 mm inferior to the second bicuspid apex and 2 cc of anesthetic are injected.
Ear
Distribution
External ear
Anatomy
The anterior auricle, temporal scalp and alteral temple are supplied by the auriculotemporal nerve emerging anterior to the auditory canal and passing superiorly superficial to the zygomatic arch. The posterior auricle and angle of the jaw are supplied by the greater auricular nerve which arises from the cervical plexus and emerges from the posterior border of the of the sternocleidomastoid muscle and travels anteriorly behind the auricle.
Technique
Direct injection of the pinna can cause tissue necrosis so a regional field block around the auricle is required. Four injection points, on at each corner of the base of the ear, are used and the needle is advanced so anesthetic is infiltrated on all four side of the auricle (11, 12, Tint).
Tongue
Distribution
The anterior two-thirds of the tongue, floor of the mouth and gums
Anatomy
The lingual nerve runs close together with the inferior alveolar nerve at the mandibular foramen.
Technique
The lingual nerve is blocked using the same intraoral approach as the inferior alveolar nerve block described in the Dental Blocks section. The lingual and alveolar nerves can be blocked together using this technique.
The face is among the most common anatomical sites for the utilization of regional nerve blocks. Direct infiltration into delicate facial structures can be very painful, and may distort the local anatomy, thus preventing proper comestic repair of facial lacerations. 