Acne Scar Treatment
Microneedling or Dermaroller
A dermaroller is a skin needling device with many small surgical needles. Dermarollers with needle lengths between 1.5 mm and 2.5 mm are suited for acne scar revision. The needle diameter (thickness) is approximately 0.25 mm at their base.
Mechanism of Action
Dermarolling remolds the skin by creating thousands of microscopic channels through the skin, increasing the formation of new tissue by activating the body’s wound healing cascade (hemostasis-inflammation-proliferation-tissue remodeling). The microchanneling causes the release of growth factors that promote scarless healing, and the deposition of normal woven collagen rather than scar collagen. The fibroblasts are responsible for collagen production.
After topical anaesthesia, the dermaroller is rolled over various quadrants of the face in different directions till pin point bleeding is seen. Sessions are done once in 6 weeks, upto four sittings. Adverse Effects Pain, infection, bleeding, scabbing, hyperpigmentation.
Acne Scar Treatment Combination Techniques
Microneedling with 35% glycolic acid peel shows significant improvement in scars without increasing morbidity.
These work through selective thermal stimulation of dermal collagen to increase local proliferation while sparing the epidermis. These include multiple wavelength laser (532 KTP, 585 PDL, 1064Nd:YAG, 1320 Nd:YAG, 1450 Diode, 1540 Erbium glass). These lasers are safer in darker skin individuals, have minimum downtime, but are less effective and are useful only in rolling and hypertrophic scars. Although nonablative, epidermal cooling is required for protection of superficial tissues.
IPL, radiofrequency (RF), and plasma devices work as alternative devices for management of acne scars. These work on the same principles as nonablative lasers with approximately similar results and limitations. IPL can offer some rejuvenation, whereas RF and plasma devices are “color blind” and, hence, have minimal risk of postin-flammatory dyspigmentation.
Fractional photothermolysis is a further innovation in resurfacing technique that was developed in response to the safety concerns of full ablative therapies, and the modest efficacy results demonstrated for the nonablative therapies. This technique is based on the creation of spatially precise microscopic thermal zones (MTZs) at depths of 200–500 μm and spaced at 200–300 μm intervals, leaving surrounding tissue intact. It stimulates collagen remodeling and neocollagenesis in a columnar fashion leaving surrounding rings of viable tissue, sparing the noninvolved, intertreatment epidermal and dermal regions. It was first described using a 1550-nm erbium fiber laser Fraxel®, Solta Medical Inc., Hayward, CA),72,73 although other fractional laser devices are now available (e.g., Fractional CO2, Er:YAG, Er:glass).
This method differs from other resurfacing techniques in that damaged epidermal components are extruded by viable keratinocytes at the lateral margins of the MTZs and exfoliated after few days. Epidermal tissue that is spared between thermal zones contains viable cells capable of rapid reepithelialization. Fractional lasers are available as ablative (CO2, Er:YAG) as well as nonablative (Er:glass, Er:fiber). The stratum corneum remains intact in treatment with nonablative fractional lasers. The gradual exfoliation of the epidermis following fractional resurfacing also results in improved superficial dyspigmentation. This technique generally requires series of treatments for best clinical improvement, which can achieve results for atrophic scars similar to that of traditional ablative laser skin resurfacito ablative techniques, adverse effects are typically mild and transient, including erythema, periocular edema, and a slight bronzing of the skin.
Side effects: Most common side effect seen with Er:YAG 2940 nm fractional laser resurfacing was exacerbation of acne lesions (13%), which was treated with oral antibiotics, post treatment pigmentation was seen only in 2% and prolonged crusting (more than 7 days) was seen after 3% of the sittings. Other side effects include transient erythema or edema, dryness, milia, or rarely infection.
Fractional radiofrequency devices have been recently tried for acne scars. Platelet Rich Plasma Platelet rich plasma (PRP) which is gaining popularity in various cosmetic and antiaging therapies has also shown promising results in treatment of acne scars. The background of use of this method is the use of knowledge that following an injury, clot formation is responsible for hemostasis and initiation of healing process. This is brought about by release of biologically active proteins from platelet derived α-granules. PRP technique was used to have a serum/coagulum that has a much higher concentration of growth factors (in comparison to a normal clot) and theoretical presumption that it will help in tissue repair/augmentation.It is a technique where patient’s whole blood (30–40 ml) is collected and following differential centrifugation, plasma rich in platelets is harvested. The platelets collected in PRP are activated by the addition of thrombin and calcium chloride, which induce the release of these factors from alpha granules. The growth factors and other cytokinesng. present in PRP include:75,76 platelet-derived growth factor, transforming growth factor beta, fibroblast growth factors, vascular endothelial growth factor, epidermal growth factor, and interleukin 8. Lee et al77 carried out a split-face trial in 14 Korean participants with acne scars. All participants received one session of ablative CO2 fractional resurfacing, following which facial halves were randomly assigned to receive treatment with autologous PRP injections on one side (experimental side) and normal saline injections on the other side (control side).
The participants were monitored for degree of recovery and resurfacing-associated adverse events, including prolonged erythema, edema. Results showed that PRP after fractional resurfacing enhances recovery of laser-damaged skin and also improved the clinical appearance of acne scarring. Zhu et al showed similar benefits on combining Erbium fractional laser with PRP.