Choosing Acne Scar Treatment: Matching Treatment to Scar Type

Is every mark left after acne a scar?

No. Colour change after acne should be distinguished from true structural scarring.

Brown or darker marks may predominantly reflect increased pigmentation, while red marks may have a vascular or inflammatory component. Atrophic acne scars involve an actual depression in the skin surface. Hypertrophic scars and keloids behave differently and are raised rather than depressed.

This distinction matters because colour, surface texture and deeper tissue loss are different treatment targets.

How long the scar has been present and whether acne is still active are also relevant. Prospective evidence has shown an association between persistent erythematous or pigmented acne marks and the subsequent development of atrophic scars. Ongoing inflammation therefore should not automatically be viewed as a colour issue alone. ¹

Which treatments are considered for different scar features?

A useful way to approach acne scars is to identify the dominant problem rather than choosing treatment from the scar label alone.

These are not rigid treatment assignments. Several problems can coexist in the same face, and some treatments may affect more than one component.

Do ice pick, boxcar and rolling scars still matter?

Yes. These terms remain useful for describing scar shape, but they do not determine treatment on their own.

Ice pick scars are usually narrow and deep. Boxcar scars are wider and may have more sharply defined edges. Rolling scars tend to create broader depressions with smoother transitions into the surrounding skin.

Depth and edge characteristics are particularly important in boxcar scars. A shallow boxcar scar may not require the same approach as a deep scar with sharply defined edges.

With rolling scars, how the depression moves with the surrounding tissue and whether it appears tethered to deeper structures can also change the treatment plan.

Scar morphology therefore provides a common descriptive language rather than a fixed treatment prescription.

Why are focal treatments considered for narrow, deep scars?

Treating the entire skin surface may not adequately reach the deepest part of a narrow scar. In selected scars, a treatment directed at the individual depression may therefore make more sense.

TCA CROSS, selected focal treatments and small punch procedures are among the approaches described for this type of scar.

There is no single hierarchy that applies to every patient. Studies include different scar patterns and different treatment techniques.

An older uncontrolled CO₂ laser series by Koo and colleagues also illustrates why deeper acne scars may require treatment directed at the individual defect rather than surface resurfacing alone. ⁷

When does subcision make sense for rolling scars?

Subcision is mainly considered for broad atrophic depressions that appear attached to deeper tissue. The aim is to release fibrotic attachments that pull the scar downward.

I do not decide on subcision from the scar label alone. I consider the depth of the depression, how it moves with the surrounding tissue and whether volume loss is contributing to its appearance. If I do not find clear fixation, I first consider whether volume loss or surface irregularity is the more important problem. In that situation, subcision is not an automatic choice.

Colour change alone, a narrow ice pick scar, or a superficial texture problem without evidence of deeper attachment is not by itself a reason for subcision. Fibrotic resistance encountered during the procedure helps guide the extent of release rather than determining whether subcision was indicated in the first place.

How does volume loss change the plan?

Some depressions are influenced by more than the scar surface itself. Loss of tissue support over a broader area can make scarring appear deeper.

In this situation, dermal filler or fat transfer may be considered to restore support. Their role is different from treating an individual narrow deep scar or releasing a tethered depression.

The presence of scars at different depths and with different structural characteristics is one reason why treatment may sometimes need to address more than one tissue level. ²

Is RF microneedling more effective than conventional microneedling?

Current evidence does not establish a reliable overall superiority of one over the other.

Conventional microneedling creates controlled mechanical microinjury to stimulate collagen remodelling. RF microneedling adds controlled radiofrequency heating delivered through the needles.

In the 2022 systematic review and meta-analysis by Shen and colleagues, conventional microneedling and RF microneedling appeared in separate subgroup analyses, but the two techniques were not directly compared against each other. Those subgroup results therefore cannot establish that one is generally superior. ³

Choice depends on the scar pattern, skin characteristics, expected recovery and the tissue level being targeted.

When can fractional CO₂ laser be useful?

Fractional CO₂ laser can be useful when surface irregularity and deeper dermal remodelling are important treatment targets.

If there is significant tethering, very deep individual scars or volume loss, resurfacing alone may be insufficient.

A 2026 systematic review and meta-analysis compared fractional CO₂ with nonablative Er:Glass laser. No statistically significant difference in efficacy was demonstrated, but the number of studies and participants was small, so this should not be interpreted as proof of equivalence. Er:Glass was associated with less pain and shorter periods of erythema and crusting. A significant difference in post-treatment pigmentation was not demonstrated. ⁴

Laser choice therefore depends on more than device power. Scar structure, pigmentation tendency and acceptable recovery time also matter.

Why are treatments sometimes combined?

Different structural problems can coexist in the same face. One treatment may address tethering while another targets surface texture, focal deep scars or volume loss.

For example, broad tethered depressions may coexist with a few narrow deep scars and more general surface irregularity. A single technique may not address all of these to the same degree.

Small comparative studies suggest that adding another treatment can improve outcomes in some settings, but they do not always identify how much improvement comes from each individual component.

The purpose of combination treatment is therefore not to increase the number of procedures. It is to address a second problem when a genuinely different treatment target is present.

Can acne scar treatment begin while acne is still active?

When significant inflammatory acne remains active, preventing further scarring becomes a priority. Active nodules or pustules in the treatment area may affect the timing of procedures that create controlled injury to the skin. There is, however, no universally established requirement that every active lesion must disappear before any scar treatment can be considered. International consensus on energy-based devices for acne scars also addresses active acne as a distinct clinical consideration when selecting treatment. ⁵

The severity of active disease, the area being treated and the degree of tissue injury created by the planned procedure all matter.

Do I need to wait 6 or 12 months after isotretinoin?

Evidence does not support an automatic 6 or 12 month delay for every procedure, but the type of procedure matters. Spring and colleagues found insufficient evidence to support routine delay for fractional ablative and nonablative lasers, superficial chemical peels and certain cutaneous surgical procedures, while fully ablative laser resurfacing and mechanical dermabrasion were not recommended during systemic isotretinoin treatment. ⁶

More focal and deeper chemical techniques such as TCA CROSS should not automatically be assumed to fall within evidence concerning superficial chemical peels. They require separate clinical judgement.

The relevant question is therefore not simply whether isotretinoin has been used, but also what procedure is being considered and how much tissue injury it produces.

Does skin type change treatment selection?

Yes. A previous tendency to develop significant post-inflammatory hyperpigmentation after treatment is particularly relevant.

There is not enough evidence to place every acne scar treatment into a reliable low, medium or high risk category for darker skin types. Fitzpatrick V and VI skin types remain less represented in many studies.

Skin type therefore does not automatically exclude a procedure. Previous pigmentation, ongoing inflammation, sun exposure and the amount of heat or surface injury created by the treatment all need to be considered.

Can acne scars disappear completely?

For atrophic acne scars, a realistic goal is usually improvement rather than complete disappearance. Treatment may reduce the depth of a depression, soften the transition at its edges and make the skin surface appear more even.

Results vary according to scar type, depth and the other structural problems present. A fixed number of sessions or a universal improvement percentage is therefore not appropriate.

After treatment, the remaining dominant problem can be reassessed and the next step selected accordingly.

What should the next step be?

The first step is not choosing a device. It is deciding whether the main problem is colour, surface irregularity, an individual deep scar, a broad tethered depression, volume loss or a combination of these.

During examination, I look at scar structure, depth, movement relative to the surrounding tissue and the contribution of volume loss. This helps determine which problem should actually be targeted first.

Once that distinction is clear, one treatment may be sufficient or treatment can be planned in stages.

Acne Scar Treatment