INTRODUCTION
Acne vulgaris is a very common cutaneous disorder with a multifactorial etiology. The development of acne vulgaris involves increased sebum production, follicular hyperkeratinization, Cutibacterium acnes colonization, and upregulated inflammatory responses.1 The inflammatory destruction created by acne vulgaris can leave behind atrophic acne scarring, posing a significant negative psychosocial impact on patients.1,2 Atrophic acne scarring can be classified into 3 main types: rolling, boxcar, and icepick scars. Patients can present with 1, 2, or all 3 scar types, therefore, an in-depth and nuanced evaluation of patients is imperative to pursue appropriate therapeutics.1 Microneedling involves the creation of multiple microchannels within the skin that physically disrupt the dysregulated collagen bundles present within the superficial layer of the dermis of acne scars, and promotes the production of new collagen and elastin beneath the scars.3 This controlled tissue microinjury triggers a cascade of wound healing events involving the release of multiple growth factors, including but not limited to platelet-derived growth factor (PDGF), fibroblast growth factor (FGF), and transforming growth factor (TGF)- alpha and beta. Microneedling-induced fibroblast proliferation fosters the deposition of type 3, and ultimately type 1, collagen in an organized pattern.3 There are multiple microneedling devices present on the market, which vary based on needle length, diameter, material, and quantity. The optimal parameters for microneedling have not been well defined and likely vary based on the targeted disease process.3 Platelet-rich plasma (PRP) is an autologous preparation of plasma that contains a supraphysiologic concentration of platelets. Upon activation, the alpha-granules of platelets release high concentrations of growth factors such as TGF-β, PDGF, vascular endothelial growth factor (VEGF), epidermal growth factor (EGF), insulin-like growth factor (IGF), and other chemokines and cytokines, which aid in cell differentiation, proliferation, and regeneration.4 Thus, the combination of PRP and microneedling has been postulated to provide synergistic benefits to patients as the application of PRP following microneedling allows for deeper penetration of the agent and, thus, rapid-acting and effective treatment.
