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Neurotoxin
Neurotoxin
Botulinum toxin (BTX) is the most widely used treatment for platysmal bands and dynamic rhytides.7โ9 Deep intradermal injections using small doses placed equidistantly across multiple sites along the length of each vertical band produces a gentle anterior neck lift and consistently softens the prominence of the cords on animation. Injecting the bands may also diminish horizontal โnecklaceโ lines in some patients, but this is inconsistent. Guidelines recommend a total dose of 30 to 60 U onabotulinumtoxinA divided among all injection points, as determined by patient assessment and clinical experience.10
Loss of definition along the jawโan invariable effect of changing anatomy over time โmay be improved via the so-called Nefertiti Lift, in which small doses of BTX (15 U onabotulinumtoxinA per side) are injected in multiple sites under the mandible and intradermally into the upper half of the actively contracting posterior platysmal band to sharpen the contours of the jaw and raise the corners of the mouth.10,11
Not everyone is a good candidate for neurotoxin injections in the neck; some precautions are advised. BTX works best on younger patients with good skin elasticity or postoperatively for residual bands.12 In individuals with extensive cutaneous laxity, poor cervical skin elasticity, and flaccid platysmal cords, injections can worsen the appearance of the neck. Large dosesโin excess of 50 U onabotulinumtoxinA in one sessionโcan produce weakness in the neck flexors and dysphagia and should be avoided.9,11
Alternatively, microbotoxโthe injection of multiple microdroplets of dilute onabotulinumtoxinA into the dermis or the interface between the dermis and superficial layer of facial musclesโis a simple alternative for patients with early signs of aging in the neck.13 Microinjections target the superficial fibers under the surface of the skin, decreasing sweat and sebaceous gland activity for an intradermal effect. In the neck, tiny blebs injected as superficially as possible across the entire sweep of the platysma muscle improves skin texture, color, and smoothness, reduces the appearance of horizontal necklace lines and vertical banding, and creates a lifting effect of the jowls and jawline for better cervicomental contouring.13