How I Treat Acne Scars: TCA CROSS, Subcision, CO2 Laser and Endolaser

Acne scars are one of the most rewarding things I treat, but also one of the most misunderstood. The single biggest reason people are disappointed by acne scar treatment is that they are given one technique for every scar, when in reality different scars need completely different approaches.

So rather than offering a single magic treatment, I assess the scars carefully and combine the right tools for each type. TCA CROSS, subcision, CO2 laser and Endolaser each do something the others cannot, and used together they produce far better results than any one alone. Here is how I think about it.

Overview

Why acne scars are not all the same

Most people have a mix of scar types, and recognising them is the key to treating them:

• Ice-pick scars, deep, narrow pits that look as though the skin was pierced with a fine point.

• Boxcar scars, wider depressions with defined edges, like small craters.

• Rolling scars, broad, shallow undulations caused by tethering beneath the skin.

• Redness and pigmentation, the red or brown marks left behind, which are not true scars but often the first thing people notice.

The first rule: treat active acne first

Before any scar work, active acne needs to be under control. Treating scars while breakouts continue simply creates new scarring, so settling the acne first is non-negotiable. It is also worth giving fresh scars time, as some redness and unevenness improves on its own in the months after a breakout.

How I treat acne scars

TCA CROSS for ice-pick scars

TCA CROSS, which stands for chemical reconstruction of skin scars, is my treatment of choice for deep, narrow ice-pick scars. A high-strength trichloroacetic acid is applied with precision into the base of each individual scar, triggering a controlled healing response that stimulates new collagen and gradually lifts and narrows the scar. It is done over a series of sessions and is particularly valuable for scars that lasers struggle to reach.

Subcision for rolling and tethered scars

Rolling scars are caused by fibrous bands tethering the skin to the tissue beneath, which pulls the surface down. Subcision releases these bands using a fine needle or cannula passed under the scar, freeing the skin so it can lift, while the controlled injury stimulates new collagen to fill the space. For tethered, rolling scars, nothing else works in quite the same way.

CO2 laser for texture and resurfacing

For overall texture, boxcar scars and general smoothness, fractional CO2 laser resurfacing is a cornerstone. It removes precise columns of damaged skin and drives deep collagen remodelling, improving the depth and definition of scars across a whole area. It involves a few days of downtime, and in darker skin types the settings must be chosen carefully to protect against pigment changes.

Endolaser for collagen stimulation from beneath

Endolaser works from below the surface, delivering laser energy through a fine fibre into the deeper layers of the skin. By stimulating collagen and remodelling tissue from underneath, it complements surface treatments and supports the release achieved with subcision, helping firm and rebuild the scarred area. It is a useful part of the toolkit for deeper, more stubborn scarring.

How I combine them

The real skill is in sequencing. A typical plan might release rolling scars with subcision, treat ice-pick scars with TCA CROSS, resurface the texture with CO2 laser, and use Endolaser to stimulate collagen from beneath, all staged sensibly across several appointments. I also support the skin's recovery with regenerative treatments where helpful, and address redness and pigment separately.

Care

Managing redness and pigmentation

The red and brown marks left by acne are not scars in the structural sense, and they often respond to different measures, including time, sun protection, targeted topicals and gentle treatments to even tone. Supporting overall skin quality with regenerative options such as polynucleotides can also help the skin recover and look healthier alongside scar treatment.

What results to expect

Acne scarring improves gradually and through a course of treatment, not overnight. With the right combination, significant improvement is very achievable, but complete erasure is rarely realistic, and I would always rather promise honestly and over-deliver. Collagen takes months to remodel, so the final result is best judged well after the last session.

Ready to do something about acne scarring? A consultation at Dr Vahe Clinic will map your scar types and build a combined plan using the right techniques for your skin. Book a consultation.

A personal note

Acne scars carry a weight far beyond the skin, and treating them well can be genuinely life-changing. That is exactly why they deserve a tailored, combination approach rather than a one-size-fits-all laser package.

My aim is honest, meaningful improvement, built carefully over time and matched precisely to your scars. That is the approach behind every acne scar plan I create in Chelsea.

Frequently asked questions

Can acne scars be removed completely?

Complete erasure is rarely a realistic promise. With the right combination of treatments, however, most acne scarring can be improved very significantly, often by well over half, so that it is far less noticeable. Honest expectations are part of a good result.

Which treatment is best for ice-pick scars?

Deep, narrow ice-pick scars respond best to TCA CROSS, where a high-strength acid is applied precisely into each scar to stimulate collagen and remodel it. Broad resurfacing lasers are less effective for this particular scar shape.

Is there downtime with acne scar treatment?

It varies by treatment. Subcision and TCA CROSS involve some bruising or temporary marks, while CO2 laser needs several days of redness and healing. Endolaser and regenerative treatments are gentler. Your plan will set out the downtime for each step.

How many sessions will I need?

Acne scarring almost always needs a course rather than a single treatment, commonly three or more sessions spaced over months, because collagen remodels slowly. The exact number depends on the type and depth of your scars.

References

1. Jacob CI, Dover JS, Kaminer MS. Acne scarring: a classification system and review of treatment options. Journal of the American Academy of Dermatology. 2001;45(1):109-117.

2. Lee JB, Chung WG, Kwahck H, Lee KH. Focal treatment of acne scars with trichloroacetic acid: chemical reconstruction of skin scars method. Dermatologic Surgery. 2002;28(11):1017-1021.

3. Orentreich DS, Orentreich N. Subcutaneous incisionless (subcision) surgery for the correction of depressed scars and wrinkles. Dermatologic Surgery. 1995;21(6):543-549.

4. Ong MWS, Bashir SJ. Fractional laser resurfacing for acne scars: a review. British Journal of Dermatology. 2012;166(6):1160-1169.

This article reflects general clinical experience and does not replace personalised medical advice. Reviewed by Dr Vahe Karimyan MD, MS, PhD.