Scarring is one of the most sensitive issues with skincare. It’s very difficult to heal scars and do so properly and permanently. For this reason, patients who come to us put a lot of faith in our understanding of scars and how to help heal them.
Among one of the worst culprits in scarring is acne vulgaris. This is a common skin disease that frequently results in scarring, leading to physical disfigurement with a profound psychosocial impact. Early, aggressive, and effective treatment is the best way to minimize and prevent acne scarring. Accutane (isotretinoin) should be considered for any acne patient that has scarring potential. To find out more about Accutane, please check out my previous blog.
Although there are many scar treatments, no single therapy removes acne scars completely. To achieve best cosmetic results, typically, multiple different treatments are needed. Selection of the appropriate treatment depends on type/degree of acne scarring, patient preference, side effects/down-time, cost, and treatment availability.
How are acne scars classified?
“Acne scars are classified based on their appearance on physical exam. They can be depressed (atrophic scars) or raised (hypertrophic scars/keloids).”
Atrophic scars are the most common type of acne scars and they are caused by the destruction of collagen, and present as indentations.
Atrophic scars can be classified into three categories: ice pick, rolling, and boxcar scars.
Ice pick scars
These are narrow (less than 2 mm), deep, and sharply demarcated tracts. They are wider at the top of the skin and taper as they go deeper.
This type of scarring is usually wider (4-5mm) and are more shallow than ice pick scars. They have an undulating appearance with the rise and fall of skin surface due to abnormal collagen attachment.
These scars are wider at the base compared to ice pick scars and do not taper. They are typically round or oval shaped dimples that can either be shallow (less than 0.5mm) or deep (more than 0.5mm)
Hypertrophic scars and keloids
These are less common and are characterized by collagen gain, resulting in a firm raised lesion. Hypertrophic scars stay within the margin of the wound whereas keloids extend beyond the wound margin.
How are atrophic acne scars treated?
The ideal way to treat acne scars is a three-step approach, consisting of (1) an initial treatment phase, (2) a collagen remodeling procedure, and (3) additional treatments to address resistant scars and to supplement results of previous procedures.
Step 1: An initial treatment phase.
The goal of this phase is to treat scar erythema (redness) and treat individual scars that may be resistant to collagen remodeling procedures. Treating erythema is important as the redness accentuates the scar and makes it more noticeable.
To target erythema, the treatment of choice is the pulse-dye laser. Typically, it requires three to four treatments spaced out every month.
To treat individual scars that may be resistant to other treatments, typically a surgical approach is preferred. Ice pick and narrow boxcar scars respond to the chemical reconstruction of skin scars technique (CROSS technique) where a high-strength (90-100%) trichloroacetic acid (TCA) peel solution is placed at the base of scars with the goal to promote dermal remodeling.Rolling acne scars are typically treated with subcision, a procedure in which a small needle is inserted under an acne scar with the goal of releasing the fibrosis tissue that teethers the scar and causes the depression.
Finally, another option to treat difficult ice pick and boxcar scars is to surgically remove them by punch biopsy.
Step 2: A collagen remodeling procedure.
Since atrophic scars result from a loss of collagen, this phase of treatment consists of procedures meant to induce collagen growth. Examples of treatments that can induce collagen growth include traditional ablative laser resurfacing, nonablative fractional laser resurfacing, ablative fractional laser resurfacing, chemical peels, dermabrasion, and skin microneedling with platelet-rich plasms (PRP).
Traditional ablative laser resurfacing
This uses either of a 2940 nm erbium:yttrium aluminum garnet (Er:YAG) laser or 10,600 nm carbon dioxide (CO2) laser. It is the most effective, but most aggressive procedure that may not be tolerated by all patients. These lasers target water, causing the precise ablation of the epidermis and dermis leading to thermal injury which promotes collagen remodeling. This procedure is rather invasive and requires multiple weeks of down-time.
Nonablative fractional laser resurfacing (NAFR)
As an attractive alternative to traditional ablative laser resurfacing due to less down time (one to three days), this is a highly effective treatment. Most commonly, the 1550nm or 1540nm NAFR lasers are used to ablate a narrow microscopic column of skin instead of ablating the entire surface. However, the results are more limited and require multiple treatments.
These can be effective treatments for acne scars as the injury caused by the peel stimulates collagen remodeling. Chemical peels are classified by the depth of skin injury. Superficial chemical peels (salicylic acid, lactic acid, Jessner solution, 10% to 25% TCA) affect only the epidermis. Medium depth chemical peels (combination of Jessner solution and 35% to 50% TCA) penetrate to the superficial (papillary) dermis. Deep chemical peels (phenol, croton oil) injure the skin down to the deeper (reticular) dermis.
This skin procedure involves the use of tools (high-speed brush, sandpaper) to remove the epidermis or part of the dermis. This procedure is highly operator-dependent and meticulous, but it allows the doctor to etch scar edges precisely.
Microneedling can improve acne scars by acting similar to NAFR lasers by inducing small columns of skin damage, which can stimulate collagen growth. Advantages are low cost and short recovery time. One way to potentiate the results from skin microneedling is to use platelet-rich plasma (PRP) drawn from the patient, which contains granules of growth factors, which further stimulate collagen turnover.
Step 3: Additional treatments to address resistant scars and to supplement results of previous procedures.
After performing a collagen remodeling procedure, it is important to assess the patient for treatment response and to determine if any other procedure would be beneficial. Possible treatment options during this phase include all of the aforementioned treatments of Step 1 along with injectable soft tissue fillers.
Dermal fillers are particularly helpful for broad, rolling scars that are soft and disappear when the surrounding skin is stretched. Ice pick scars and other tethered scars typically do not respond well to fillers and can even look worse.
How are hypertrophic acne scars and keloids treated?
First line treatment involves corticosteroid injections which help decrease inflammation and collagen growth. Typically, this treatment is repeated every four to six weeks for up to four treatments. Additional treatments include surgical excision, pulse-dye laser, radiotherapy, and intralesional 5-fluorouracil.
Have some acne scars that need some clearing up? Book an appointment with us so we can take care of your specific scars the right way.