Acne scars are permanent structural changes in dermal tissue that occur during the healing process of acne lesions. The three main acne scar types — ice pick, rolling, and boxcar scars — have distinct morphological characteristics, and each requires a different treatment approach.
Ice Pick Scars
Ice pick scars are narrow, deep atrophic scars that appear as though punctured by an ice pick. They are typically less than 2 mm in diameter and can extend into the dermis or subcutaneous tissue. They are considered the most difficult type of acne scar to treat.
For the treatment of ice pick scars, the TCA CROSS (Chemical Reconstruction of Skin Scars) technique is regarded as the gold standard. High-concentration trichloroacetic acid (70–100%) is applied to the base of the scar with a fine-tipped applicator to create controlled tissue injury and trigger new collagen synthesis.
Rolling Scars
Rolling scars are shallow depressions with a broad base (4–5 mm) that create an undulating, wave-like surface. They form as a result of fibrous bands tethering the dermal tissue to deeper layers. They become more prominent under directional lighting due to shadow effects.
For rolling scars, subcision (subcutaneous incision) is the most effective method. The fibrous bands beneath the skin are cut and the scar base is released. Better outcomes are achieved when this procedure is combined with dermal fillers or platelet-rich plasma (PRP).
Boxcar Scars
Boxcar scars are round or oval depressions with sharp, well-defined edges and a flat base. They are subdivided into superficial and deep based on their depth. These scars, which resemble chickenpox scars, are typically 1.5–4 mm in diameter.
Superficial boxcar scars can be treated with laser resurfacing and chemical peels, while deeper ones may require punch excision or punch elevation techniques.
Grading and Assessment
The Goodman and Baron Classification is widely used to determine the severity of acne scars. This classification grades scars from mild (Grade 1) to severe (Grade 4) to guide treatment planning.
- Grade 1: Mild — macular erythematous or pigmented marks
- Grade 2: Moderate — mild atrophic or hypertrophic scars
- Grade 3: Severe — pronounced atrophic or hypertrophic scars
- Grade 4: Very severe — deep atrophic scars and sinus tracts
Combination Treatment Approach
In modern acne scar treatment, a multimodal approach yields the best outcomes. Because different scar types are often present simultaneously, a combination of multiple techniques is preferred over any single method. Fractional laser, microneedling, TCA CROSS, subcision, and dermal fillers can all be applied together within a personalized treatment protocol.
This article is for informational purposes only. Please consult a qualified physician for treatment decisions.