Local Anesthetics in Cosmetic Dermatology
Local anesthetics play an important role in cosmetic dermatology. Techniques using topical and regional anesthesia provide numerous pain management options for laser and injection treatments. In this article, we review strategies to maximize patient comfort during cosmetic interventions.
Practice Points
- The proper delivery of local anesthesia is integral to successful cosmetic interventions.
- Regional nerve blocks can provide effective analgesia while reducing the number of injections and preserving the architecture of the cosmetic field.
Blocks for Dermal Fillers
Forehead
For dermal filler injections of the glabellar and frontalis lines, anesthesia of the forehead may be desired. The supraorbital and supratrochlear nerves supply this area. The supraorbital nerve can be injected at the supraorbital notch, which is measured roughly 2.7 cm from the glabella. The orbital rim should be palpated with the nondominant hand, and 1 to 2 mL of anesthetic should be injected just below the rim (Figure 1). The supratrochlear nerve is located roughly 1.7 cm from the midline and can be similarly injected under the orbital rim with 1 to 2 mL of anesthetic (Figure 1).
Lateral Temple Region
Anesthesia of the zygomaticotemporal nerve can be used to reduce pain from dermal filler injections of the lateral canthal and temporal areas. The nerve is identified by first palpating the zygomaticofrontal suture. A long needle is then inserted posteriorly, immediately behind the concave surface of the lateral orbital rim, and 1 to 2 mL of anesthetic is injected (Figure 1).
Malar Region
Blockade of the zygomaticofacial nerve is commonly performed in conjunction with the zygomaticotemporal nerve and provides anesthesia to the malar region for cheek augmentation procedures. To identify the target area, the junction of the lateral and inferior orbital rim should be palpated. With the needle placed just lateral to this point, 1 to 2 mL of anesthetic is injected (Figure 1).
Blocks for Perioral Fillers
Upper Lips/Nasolabial Folds
Bilateral blockade of the infraorbital nerves provides anesthesia to the upper lip and nasolabial folds prior to filler injections. The infraorbital nerve can be targeted via an intraoral route where it exits the maxilla at the infraorbital foramen. The nerve is anesthetized by palpating the infraorbital ridge and injecting 3 to 5 mL of anesthetic roughly 1 cm below this point on the vertical axis of the midpupillary line (Figure 1). The external nasal nerve, thought to be a branch of cranial nerve V, also may be targeted if there is inadequate anesthesia from the infraorbital block. This nerve is reached by injecting at the osseocartilaginous junction of the nasal bones (Figure 1).
Lower Lips
Blockade of the mental nerve provides anesthesia to the lower lips for augmentation procedures. The mental nerve can be targeted on each side at the mental foramen, which is located below the root of the lower second premolar. Aiming roughly 1 cm below the gumline, 3 to 5 mL of anesthetic is injected intraorally (Figure 1). A transcutaneous approach toward the same target also is possible, though this technique risks visible bruising. Alternatively, the upper or lower lips can be anesthetized using 4 to 5 submucosal injections at evenly spaced intervals between the canine teeth.18
