Percutaneous collagen induction (microneedling) for the management of non-atrophic scars: literature review

INTRODUCTION: Percutaneous collagen induction (PCI) or needling techniques are increasingly popular in the reconstructive and aesthetic arena. The underlying mechanisms of action rest on producing a pattern of non-ablative and non-confluent puncture wound pattern to the dermis with a resulting regenerative effect to the skin. METHODS: A detailed English literature review was conducted using PubMed Medline, Embase and Web of Science; the manuscripts were appraised and classified according to level of evidence as well risk of bias. Results are presented in descending order of evidence for non-atrophic scars. DISCUSSION: On the basis of level 1 evidence currently available, the combination of needling and silicone gel can improve the short-term pliability, height and vascularity of hypertrophic and keloid scars. According to level 2 evidence, needling alongside spray keratinocytes can produce a statistically significant improvement to patient/observer scar ratings and improve pigmentation in hypopigmented burn scars at 12-month follow-up. Results from mixed cohort studies also point towards needling having a beneficial effect on fat graft retention. Level 3 data suggest that needling can render significant resurfacing effects to both mature and actively hypertrophic burn scars at 12-month follow-up based on objective scar scales; furthermore, favourable histological changes are seen, including better collagen alignment in the dermis and increased epidermal thickness. CONCLUSION: Needling techniques are promising adjuncts to non-atrophic scar management. Further research with long-term follow-up and comparative design protocols incorporating other resurfacing modalities is warranted before the exact value of needling is delineated in scar management protocols.