We currently live in a society that places a premium on youthful appearance. However, our busy lives limit the amount of time we can spend in pursuit of the fountain of youth. Therefore, quick interventions with minimal recovery time are becoming extremely popular.
There are several modalities available for minimally invasive rejuvenation of the periorbital region. They include microdermabrasion, laser therapy including intense pulsed light, radiofrequency techniques, and ‘cosmeceuticals.’ Cosmeceutical agents would include retinoic acid, alpha/beta hydroxyl and glycolic acid treatments, moisturizers and sunscreens, as well as neuromodulating agents such as botulinum toxin, and dermal fillers.
Botulinum toxin and dermal fillers are currently very popular, given their minimal time investment, modest cost, minimal recovery time, efficacy, and duration of action. Maximum benefit seems to occur in patients who use botulinum toxin and fillers together.
Botulinum A Toxin
Botulinum toxin is a neuromuscular blocking agent produced by Clostridium botulinum . Botulinum toxin paralyzes muscle by inhibiting the release of acetylcholine from the presynaptic nerve terminal of the neuromuscular junction. We must remember that botulinum toxin is a paralytic agent, not a filler. It relieves rhytides formed by repetitive movements. The toxin must be injected into the offending muscle, not into the rhytid. Further, the injection must be placed at the proper level to maximally affect the muscle in question and minimize side effects. The effect typically lasts 3–4 months.
Botulinum A toxin (BOTOX®, Allergan, Irvine, CA) is approved by the United States Food and Drug Administration for the management of glabellar furrows. Off label uses in the periorbital region include management of canthal lines (crow’s feet), brow elevation, and reduction of frontal lines.
Authors vary in their preferred dosing of botulinum A toxin in the periorbital area. This author prefers a concentration of 2.5 units per 0.1cc. A tuberculin syringe with 30-guage needle works well. Some patients prefer to be injected after placement of a topical anesthetic, but most find this to be of limited value. When injecting a superficial muscle, a bleb should be raised. The toxin should be placed deeper for less superficial muscles.
Glabellar furrows (frown lines)
The target muscles for the management of glabellar furrows include the medial orbicularis oculi of the upper eyelid, the corrugator supercilii, and the procerus. The injections should be just anterior to the periosteum, as these muscles are deep. Two injections are generally placed for the corrugators and one centrally for the procerus ( Fig. 18.1 ). This region seems to have the most reliable outcomes ( Fig. 18.2 ).
Lateral canthal lines (crow’s feet)
The crow’s feet lines are generally formed by contraction of the lateral portion of the superior and inferior orbicularis muscle during squinting and laughing. Therefore, these injections should be placed laterally in an intradermal fashion with bleb formation, given the superficial location of the orbicularis muscles. The author typically places one injection above the lateral raphe (aids in brow elevation) and two injections below ( Fig. 18.1 & Fig. 18.3 ). Unfortunately, management of crow’s feet tends to be more variable than the typical success seen with glabellar injections.
Brow lift
Botulinum toxin can be useful in gently elevating ptotic brows, especially temporally. The target muscle is the temporal orbital orbicularis oculi, which depresses the lateral brow. This muscle is, again, superficial so intradermal placement with bleb formation is appropriate ( Fig. 18.1 ). Injection of 0.1–0.2cc is generally adequate. This, combined with the medial glabellar treatment, can produce nice brow elevation and reduction of secondary dermatochalasis in the lids ( Fig. 18.2 ). This chemical brow lift is most effective when combined with fillers, as described below.
Frontal rhytides
Many patients desire to have their frontal furrows reduced, both with and without facial expression. The target muscle is the frontalis, which lies just anterior to the pericranium. Therefore, injections targeting this muscle must be placed deeply. Anywhere from 0.2 to 0.4cc per side tend to be effective. The frontalis lies between the brows and normal hairline ( Fig. 18.4 ). Overtreatment can lead to eyebrow depression, counteracting the effect of brow lift efforts and closing down the eyelid space. Injections in this area are also often effective in decreasing migraine headaches.
