Treatment of Hypertrophic Scars Using Laser and Laser Assisted Corticosteroid Deliver

Keywords:medical, fiber, laser, treatment,  Time:06-11-2015

INTRODUCTION

The unprecedented survival of individuals who sustain acute burns and other trauma both on and off the battlefield has increased the necessity for effective modalities in the treatment and rehabilitation of patients [1]. Due to a complex interplay of factors such as injury mechanism and tissue tension, elevated levels of IL-4 and other procollagen cytokines may result in a net excess of collagen contributing to the newly formed hypertrophic scar [2]. Treating severe cutaneous scars is complex, and despite the best surgical care and adequate healing time, many millions of patients continue to have functional impairments and symptoms such as burning, itching, and pain. When treating hypertrophic scars, both functional and aesthetic improvement is the ultimate goal. Multiple therapeutic options have previously been described including surgical revision, laser therapy, pressure therapy, silicone gel sheets, intralesional injections, pressure garments, and adjuvant topical drug treatments [3–8]. Successful outcomes have been achieved with vascular-specific lasers when treating severe hypertrophic scars [9–11]. Alster first reported improvement after two treatments with pulsed dye lasers for hypertrophic surgical and traumatic scars. The authors also noted reductions in erythema, elevation, itching, and pain [12]. Fractional lasers were developed within the last decade and have mainly been applied to cosmetic indications such as the mitigation of rhytides [13,14]. However, there is increasing evidence that fractional lasers are an emerging therapeutic option for the aesthetic restoration and functional enhancement of traumatic scars at virtually any location on the body [14–18]. Fractional lasers create zones of ablation at variable depths determined by the treatment settings. The unique fractional injury induces a molecular cascade including heat shock proteins and other factors that lead to a rapid healing response and prolonged neocollagenesis with subsequent collagen remodeling [14]. The mechanism of improvement after ablative fractional laser therapy therefore likely includes the removal of a portion of fibrotic scar and a relative normalization of collagen structure and composition [19]. Intralesional steroid injections are a well-recognized treatment for hypertrophic scars. The procedure involves a uniform injection of 10–40 mg/ml of triamcinolone acetonide suspension with a 25- to 27-gauge needle [20]. One of the long-standing challenges of using intralesional corticosteroid for scar therapy is precise placement of the drug to avoid adverse sequelae such as fat atrophy. In their report on management of hypertrophic scars and keloids, Mustoe et al. [21] noted a recurrence rate of 45– 100% with surgery alone and less than 50% when surgery was combined with corticosteroid injection.(Medfibers supply variety of medical fiber,Disposable Bare Fiber,Diffuser Fiber,Holmium Fiber,Polyimide Fiber,Side Fire Fiber)

Effective topical delivery of any pharmaceutical agent requires the ability to penetrate the epidermis. Fractional laser therapy creates precise, uniform columns of tissue vaporization which in theory might help to facilitate drug delivery past the epidermal barrier. Haedersdal et al. [22] demonstrated this concept in an animal model, noting enhanced uptake of topical methyl 5-aminolevulinate after ablative fractional laser treatment. In this case series, we evaluated the feasibility and efficacy of same-session ablative fractional laser therapy combined with enhanced topical corticosteroid delivery. Potential benefits include the introduction of a simple, cost-effective strategy to combine two valuable scar therapies and possibly create a synergistic therapeutic response.

MATERIALS AND METHODS

Subject Population

A total of 15 consecutive subjects with hypertrophic scars resulting from burns, surgical, or other traumatic injuries present for at least one year were included (Table 1). Written informed consent was obtained from each patient. Patients were not considered for combination treatment in the setting of pregnancy, breastfeeding, oral retinoids 6 months prior to treatment, active infection, or lesions suspicious for malignancy.

Study Design

This was a prospective case series conducted to evaluate the efficacy of fractional ablative laser followed by topical triamcinolone acetonide suspension (10 or 20 mg/ml) as a treatment option for severe hypertrophic scars. The chosen concentration of triamcinolone acetonide was dependent on the location and thickness of the scar. Larger scars in locations of thicker skin, such as the back, would generally receive 20 mg/ml, while scars with a lesser degree of hypertrophy on thinner skin would receive 10 mg/ml. Each subject received a course of three to five combination treatments at 2- to 3-month intervals. Anesthesia was achieved with a topical anesthetic gel containing 20% benzocaine, 8% lidocaine, and 4% tetracaine for 1–2 hours prior to the procedure. This was followed by fractional ablative carbon dioxide (CO2) laser treatment (Ultrapulse Encore, Deep FX, Lumenis, Inc., Yokneam, Israel) over the entire scar sheet. Three of the patients also received pulsed dye laser treatment for erythema prior to the fractional treatment. Settings were customized for each patient at each treatment session according to estimated scar thickness. Pulse energies ranged from 12.5 to 20 mJ at a treatment density of 10–15%. Within 2 minutes of fractional laser treatment, a thin layer of triamcinolone acetonide suspension was drizzled over the site and rubbed gently over the ablated columns.

Post-Treatment Care

After treatment, the treatment areas were cooled with ice packs for 10 minutes. Occlusive dressings were not applied. Patients were instructed to perform acetic acid soaks and use a moisturizer three times a day for several days until healed. Patients were also directed to apply a physical sunscreen and avoid sun exposure while the study was in progress.

Clinical Assessment

To assess scar response, three blinded observers evaluated photographs taken both at baseline and at 6 months following the final therapy session. Photographs were obtained using identical camera settings, lighting conditions, and patient positioning (Nikon D300, 13.1 million total pixels, 12.3 million effective pixels). First, observers determined which photograph was ‘‘before’’ and ‘‘after.’’ They subsequently evaluated the improvements in overall appearance, dyschromia, degree of hypertrophy, and texture using a quartile scale. The following four-point scale was utilized: 0 for <25% improvement, 1 for 25–50% improvement, 2 for 50–75% improvement, 3 for >75% improvement. In no case did the observer order the before and after photographs incorrectly. For each patient, scores in each category were averaged to assign an overall score.

RESULTS

The observers accurately determined the pre- and postphotographs 45 out of 45 times. Of the four improvement parameters measured, texture received the highest improvement score, while dyschromia displayed the least numeric improvement.