Injection Therapy to Enhance Skin's Appearance

Introduction to Injection Therapies

Botulinum toxin is the oldest injection therapy to minimize the appearance of fine lines and wrinkles on one’s face.^[1] Other injectable treatments such as dermal fillers, microlipoinjection, and more alternatively, platelet-rich plasma injections can also be used to reduce the look of aging and maintain youthful-looking skin.^[1] 

How to Assess and use Injection Therapy for the Skin and Modifications

Botulinum Toxin to Enhance the Skin’s Appearance

Botulinum toxin is used as a common non-surgical procedure to maintain a youthful appearance. Botulinum toxin is a protein derived from the anaerobic bacterium Clostridium botulinum.^[1] Neural transmission is disrupted by botulinum toxin by inhibiting the release of acetylcholine at the neuromuscular junction, which causes muscle paralysis lasting around three to six months.^[1] The use of Botulinum toxin-A in the form of Botox® has been FDA approved for cosmetic purposes including temporarily diminishing the look of fine lines and wrinkles.^[1] Two other FDA approved Botulinum toxin injectors are Dysport® and Xeomin®.^[2]

Dermal Fillers to Enhance the Skin’s Appearance

Dermal fillers are another common non-surgical procedure that have a different mechanism of action than Botulinum toxin.^[3] Dermal fillers physically fill into lines and folds to correct soft tissue loss due to the aging process. Volume replacement and enhancement of the lips, nose, chin, and hands are also performed with the use of dermal fillers.^[4,5] The different types of dermal fillers include:^[6,7]

• Hyaluronic Acid
• Calcium Hydroxylapatite
• Polyalkylimide
• Polylactic Acid
• Polymethyl-Methacrylate Microspheres (PMMA)
• Collagen

Microlipoinjection/Fat Grafting to Enhance the Skin’s Appearance

Microlipoinjection is a surgical procedure to transfer one’s fat from the thigh or buttock to the face in a process known as facial rejuvenation.^[8] Fat grafting is indicated in patients who have facial hollowing and atrophy, as well as facial sagging due to aging.^[8] The collected adipose tissue is then injected into the patient’s face.^[8] One-third of the injected adipose is not reabsorbed into the body, and can remain in the injected location for years.^[8]

Platelet-Rich Plasma to Enhance the Skin’s Appearance 

Platelet-rich plasma (PRP) is a solution that contains variable concentrations of platelets from human blood.^[9] The patient's own blood is centrifuged and injected into the skin or applied topically along with ablative lasers and microneedling to stimulate collagen production and enhance the skin's appearance.^[9,10] Platelet-poor plasma (PPP) is a product of centrifugation, and may be discarded in some instances.^[11] Along with high concentration of platelets, PRP contains growth factors, transforming growth factor beta, epithelial growth factor, and vascular endothelial growth factor.^[12] There are four subsets of PRP which include: pure PRP, leukocyte and PRP (L-PRP), platelet-rich fibrin matrix (PRFM), and leukocyte-and-platelet-rich fibrin matrix.^[13]

Clinical Research and/or Case Studies for Injection Therapy for Skin

Botox and dermal fillers are well studied to be effective in temporarily reducing the appearance of lines and wrinkles.^[1,3,4] Platelet-Rich plasma is a newer aesthetic procedure, with less research. Of the studies, one, which lacked a control group, noted cosmetic improvements in the neck and face after monthly PRP injections.^[14] Crow’s feet^[15] and infraorbital wrinkles^[16] were also shown to diminish after PRP injections.

Clinical Considerations

Botulinum toxin^[1] and dermal fillers^[3] have been the most common non-surgical injectable techniques to diminish the appearance of fine lines and wrinkles, as compared to the more invasive fat grafting procedures. New literature is emerging as more research is being done on platelet-rich-plasma. A few studies have shown promising effects of PRP, but more research is needed to evaluate the safety and efficacy of injection treatments and its role in cosmetic dermatology.^[11,15]