showed good improvement (grade 2) and 25% of scars showed fair improvement (grade1) at one month follow- up after the last session.There was overall improvement in erythematous and hyperpigmented scars. Hypopigmented scars showed also improvement in color in relation to the normal surrounding skin. A study was performed by Weiss [2010] to investigate fractional laser et al. CO2 which included 15 patients having post-operative and traumatic scars. Each scar received 3 treatments at 1- to 4-month intervals; at six month follow up investigator assessment was graded as 16% of the treated scars achieving excellent improvement and 73% of treated scars achieving good improvement. Sobhy [2012] used fractional Er: YAG on different types of scars and et al. reported that , at 3 month follow up, 40% of patients had excellent improvement and 50% of patients had good improvement following 5 or more treatments. This difference may be explained by the greater number of treatment sessions, although there is some controversy about the effect of number of treatment sessions on the outcome of treatment. Also the longer period of follow up may play a role in improving the outcome of fractional laser therapy. A study utilized 1550-nm erbium-doped fractional laser, performed on 53 patients with atrophic scars showed good improvement as assessed by independent investigators in nearly 90% of the patients [Alster et al., 2007]. Texture improvement is mainly attributed to collagen remodeling and new collagen formation [Tierney and Hanke, 2010]. confirmed with immunohistochemistry that Hantash [2007] et al. persistent collagen remodeling occurred for at least 3 months after treatment
showed good improvement (grade 2) and 25% of scars showed fair improvement (grade1) at one month follow- up after the last session.There was overall improvement in erythematous and hyperpigmented scars. Hypopigmented scars showed also improvement in color in relation to the normal surrounding skin. A study was performed by Weiss et al. [2010] to investigate fractional laser CO2 which included 15 patients having post-operative and traumatic scars. Each scar received 3 treatments at 1- to 4-month intervals; at six month follow up investigator assessment was graded as 16% of the treated scars achieving excellent improvement and 73% of treated scars achieving good improvement. Sobhy et al. [2012] used fractional Er: YAG on different types of scars and reported that , at 3 month follow up, 40% of patients had excellent improvement and 50% of patients had good improvement following 5 or more treatments. This difference may be explained by the greater number of treatment sessions, although there is some controversy about the effect of number of treatment sessions on the outcome of treatment. Also the longer period of follow up may play a role in improving the outcome of fractional laser therapy. A study utilized 1550-nm erbium-doped fractional laser, performed on 53 patients with atrophic scars showed good improvement as assessed by independent investigators in nearly 90% of the patients [Alster et al., 2007]. Texture improvement is mainly attributed to collagen remodeling and new collagen formation [Tierney and Hanke, 2010]. Hantash et al. [2007] confirmed with immunohistochemistry that persistent collagen remodeling occurred for at least 3 months after treatment