Treatment of hypertrophic scars and keloids by fractional carbon dioxide laser: a clinical, histological, and immunohistochemical study

Abstract

Treatment of keloids (K) and hypertrophic scars (HTS) is challenging. A few case reports reported good results in HTS treated by fractional CO2 laser. The aim of the present study was the assessment of the clinical response as well as histological changes in K and HTS treated by fractional CO2 laser and the role of matrix metalloproteinase 9 (MMP9) in the response. A randomized half of the scar was treated by fractional CO2 laser in 30 patients (18 K, 12 HTS) for a total of four sessions 6 weeks apart. Vancouver scar score (VSS) was done before and 1, 3, and 6 months after the last laser session by a blinded observer. Biopsies taken from normal skin, untreated scar, and treated scar tissue 1 and 3 months after the laser sessions were stained by HX & E for histological changes and Masson trichrome for collagen fiber arrangement. Immunohistochemical staining for MMP9 was done in before and 1 month after samples. Quantitative morphometric analysis was done for collagen and MMP9 by image analyzer. Nineteen patients completed the 6-month follow-up period (12 K, 7 HTS). VSS score was significantly lower in the treated compared to untreated areas after 3 and 6 months in both K and HTS but was mainly due to improved pliability of the scar. Histologically, dense inflammatory infiltrate and increased vascularity was apparent 1 month after laser sessions and disappeared at 3 months. Thinner better organized collagen bundle could be seen in 3 months after samples. MMP9 was significantly increased in after treatment samples but without significant correlation with VSS. Fractional CO2 resurfacing is safe but affects mainly pliability of K and HTS with collagen remodeling apparent 3 months after therapy. MMP9 may play a role in mechanism of action of CO2 laser in K and HTS.

Fractional resurfacing in the Asian patient: Current state of the art

“…A split scar RCT showed significant reduction in Vancouver Scar Scale scores at 3 months, which remained stable at 6 months on the treated side compared to non‐treated side. Four sessions of CO 2 significantly improved the pliability of the scars, which correlated histologically with collagen remodeling and upregulation of matrix metalloproteinase (MMP)‐9 at 3 months . Low density and high energy per treatment session is necessary to achieve the desirable outcome.…”

“…Combination of these two agents has been shown to be superior to either agent alone . In terms of energy devices, hypertrophic scarring responds very well to fractionated CO 2 laser, especially to improve scar pliability and thickness . A split scar RCT showed significant reduction in Vancouver Scar Scale scores at 3 months, which remained stable at 6 months on the treated side compared to non‐treated side.…”

TATA LAKSANA LASER PADA KELOIDi

“…Komplikasi yang sering terjadi adalah luka lepuh pascalaser dan rasa nyeri minimal yang menghilang pada 1-3 hari. 8 Pada studi yang dilakukan Azzam dkk., 25 pasien ditata laksana laser FT sebanyak empat sesi dengan jarak 6 minggu dan dilakukan pemeriksaan histopatologi serta imunohistokimia pada bulan pertama dan ketiga setelah sesi laser FT terakhir. Pada studi ini, angka VSS pasien keloid mengalami penurunan signifikan setelah tiga bulan 5,6 (simpang baku 2,0) dan enam bulan 5,7 (simpang baku 2,2) dibandingkan dengan kelompok yang tidak diterapi laser FT. Pemeriksaan histopatologis kulit pada bulan pertama pascalaser FT yang terakhir menunjukkan serabut kolagen yang lebih pendek.…”

“…Pada pemeriksaan imunohistokimia ditemukan adanya peningkatan aktivitas MMP-9 yang umumnya sangat rendah pada keloid. 25 Bagan 1. Tata laksana keloid.…”

Proteases Revisited: Roles and Therapeutic Implications in Fibrosis

“…Over the last few years, antiproteolytic approach in antifibrotic therapies was restricted mainly to matrix metalloproteinases activity; however, broad range MMP inhibitors like marimastat and prinomastat failed clinical tests, as they led to severe side effects [21, 22]. Furthermore, the role of MMPs is very complicated, as during early stages of fibrosis activity of MMP-2 and MMP-9 play profibrotic function (allowing fast accumulation of fibroblasts and leukocytes) [1] that shifts, in late stages of fibrosis, toward antifibrotic, during the degradation of massive amounts of deposited ECM as shown in skin fibrosis and keloids treatment [1, 131, 132]. It emerged over the last decade that proteases involved in blood coagulation are potential targets for therapeutic interventions in treating several fibrotic disorders.…”