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14 minute read
By Dr. Michael Brandt, MD, MSc, EMBA, FRCSC, Otolaryngology Head and Neck Surgeon, FORM Face + Body, Toronto
One of the most frustrating things about acne scars is that the acne may be gone, but the reminders remain. Patients tell me they have tried skin-care products, peels, microneedling or even laser treatments, only to find that the deeper scars are still there.
The problem is that acne scarring is not one problem. Some scars are tethered to deeper tissue. Others are sharply depressed, while others involve irregular surface texture or changes in pigmentation. A treatment that improves one feature may do very little for another.
This is why I don't believe in promising that one laser, one injection or one treatment session will erase acne scars. My approach is to identify the different components of the scarring and treat them deliberately. For the right patient, that can mean combining scar subcision, platelet-rich plasma (PRP), carefully placed diluted hyaluronic acid filler and fractional CO2 laser resurfacing with our Alma Hybrid platform.
I call that treatment stacking. The idea isn't to add procedures for the sake of it. It's to address several causes of the scars, because no single treatment reliably addresses them all.
Acne scars develop when significant inflammation damages the skin's supporting structures. During healing, the body may replace damaged tissue with an uneven arrangement of collagen. Some areas become depressed because tissue volume has been lost. Others are pulled down by fibrous bands that attach the skin to deeper layers.
The result is a collection of scars that often look worse in angled lighting, where small changes in contour cast obvious shadows.
It's also important to distinguish true scars from the flat red or brown marks that can remain after acne. Those colour changes may improve gradually and can respond to different treatments. A depressed scar represents a change in the structure of the skin; it is unlikely to disappear with creams alone.
Before working on scars, I want active acne under reasonable control. Otherwise, we're trying to repair old damage while new scars are still forming.
Rolling scars create broad, shallow-looking waves or depressions across the cheeks. Their appearance often comes from fibrous bands tethering the skin to the underlying tissue.
This is an important distinction, because resurfacing the skin alone doesn't necessarily release those bands. Rolling scars are often the strongest candidates for subcision.
Boxcar scars have more distinct edges and a relatively flat or broad base. Shallow boxcar scars may improve with resurfacing and collagen remodelling. Deeper ones may need a focused procedure such as punch elevation or excision, sometimes followed by laser treatment.
Ice-pick scars are small openings that extend relatively deep into the skin. They can be especially resistant to laser treatment alone because the depth of the scar is disproportionate to its tiny surface opening.
Selected ice-pick scars may be better treated with a technique such as TCA CROSS, in which a strong chemical is applied precisely within the scar, or with a minor surgical procedure. These treatments also carry risks, including pigmentation changes and, occasionally, worsening of the scar.
Most patients have a mixture of scar types. That's why a treatment plan should begin with an examination, not with the name of a machine.
Microneedling uses fine needles to create controlled micro-injuries that stimulate a healing response and collagen remodelling. It's a reasonable option for selected mild-to-moderate atrophic scars and irregular texture, often delivered as a series rather than one session.
Its advantages can include a more manageable recovery and flexibility across skin tones when performed appropriately. But it does not reliably release substantial fibrous tethers. A series of microneedling sessions may soften the appearance of a rolling scar without actually freeing the attachment responsible for it.
Radiofrequency microneedling adds controlled heat within the tissue. It is a different procedure, with different risks and treatment depths. I would not consider it automatically interchangeable with conventional microneedling or with subcision.
Lasers work by creating a controlled injury and stimulating remodelling as the skin heals. Fractional CO2 resurfacing can improve scar edges, uneven texture and selected depressed scars. Non-ablative lasers generally involve less surface disruption, although improvement may be more gradual and multiple sessions may be needed.
Fractional CO2 is an important tool in acne-scar treatment, but it isn't magic. If a scar is firmly tethered underneath, resurfacing the surface may improve its appearance without correcting the deeper attachment.
There is also a trade-off. More aggressive laser treatment can produce more downtime, and patients may experience redness, swelling, peeling or crusting. Infection, prolonged redness, post-inflammatory pigmentation changes and, rarely, new scarring are possible. Skin tone, sun exposure and the intensity of treatment all influence the risk.
Subcision is a minor surgical technique used to release the fibrous strands holding a depressed scar down. By freeing the scar from those attachments, we can allow the skin to elevate and create an opportunity for healing in a more favourable position.
This is particularly helpful for rolling scars. It is not the ideal treatment for every ice-pick or sharply edged boxcar scar.
Subcision has its own recovery, usually involving some combination of swelling, tenderness and bruising. Less common complications include hematoma, nodules, infection, altered sensation, pigment changes or additional scarring. It requires sound anatomical judgment; it isn't simply a more aggressive version of microneedling.
Fillers can replace volume beneath selected depressed scars. PRP uses a concentration of the patient's own platelets and is sometimes added to procedures intended to stimulate tissue remodelling. Other approaches, including TCA CROSS, punch excision and punch elevation, have important roles for particular scar shapes.
None of these should be sold as a universal cure. The most effective choice depends on whether we need to release, replace, resurface or otherwise revise the scar.
For appropriately selected patients, particularly those with tethered rolling scars alongside more widespread texture changes, I use a combination of subcision, PRP, diluted hyaluronic acid filler and fractional CO2 laser resurfacing.
Each component has a specific purpose. Not every patient needs all four, and the steps may be combined or staged depending on the extent of scarring, skin type, safety considerations and expected recovery.
I start with the mechanical problem. If fibrous bands are pulling the skin down, we need to release them.
Using a canula, I work beneath selected scars to divide the attachments responsible for their depressed appearance. This is the part that a cream, superficial peel or laser cannot reliably reproduce.
The goal is not simply to create inflammation. It is to release the physical tether so the scar has a better opportunity to sit closer to the surrounding skin.
I then use PRP as an adjunct to the repair process. PRP is prepared from the patient's own blood and contains platelets and associated signalling proteins involved in tissue healing.
There is evidence that adding PRP to certain acne-scar treatments, particularly fractional laser resurfacing, can improve outcomes or shorten aspects of recovery. The studies are not uniform, however, and PRP preparation and injection techniques vary considerably.
I view PRP as a potential support for remodelling—not as a way to dissolve a scar or guarantee that new collagen will form in a particular pattern.
Once a tethered scar has been released, another concern is that the healing tissues may adhere again and the depression may partially recur.
This is where I use carefully placed, diluted hyaluronic acid filler. The goal is not to make the face fuller. It's to provide subtle support beneath selected released scars and act as a temporary spacer while the tissues heal, with the intention of reducing re-tethering.
Clinical studies support the use of hyaluronic acid filler alongside subcision, with better scar improvement than subcision alone in some comparisons. But the exact benefit of my diluted-filler technique as a barrier to re-attachment has not been established in a large controlled trial. That distinction matters.
Filler is also not risk-free. Lumps, unevenness, inflammation, infection and, rarely, vascular occlusion are possible. Product selection, dilution, placement and the amount used must be individualized. The aim is structural refinement, not indiscriminate volume.
Releasing a scar and supporting the space beneath it still may not correct the texture or sharply defined edges visible at the skin surface.
That's where fractional CO2 resurfacing comes in. At FORM, I use the Alma Hybrid platform, which provides fractional CO2 resurfacing and an additional non-ablative 1570 nm wavelength when appropriate for the treatment plan.
The CO2 component targets the superficial and dermal changes that make acne scars visible: irregular texture, scar edges and uneven collagen architecture. As the skin heals, collagen remodelling can gradually soften the contrast between scars and surrounding skin.
The combination is intentional: subcision addresses the tether, filler supports the released area, PRP may assist remodelling and the laser addresses the surface. We can also adjust the order or timing of procedures to avoid asking too much of the skin at once.
The evidence generally supports a multimodal approach, although not every combination has been tested equally well.
A controlled study comparing subcision alone with subcision plus hyaluronic acid filler or fractional CO2 laser found greater improvement with either combination than with subcision alone. A separate study of fractional CO2 plus PRP reported better clinical responses than laser alone. More recent evidence syntheses also suggest that laser-based combinations often perform well for atrophic acne scars.
This is encouraging, but it doesn't mean the benefits of four procedures can simply be added together like numbers on a calculator. Some scars respond much better than others, some treatments overlap in what they accomplish, and more treatment can also mean more swelling, downtime and risk.
The reason I combine modalities is that they target different aspects of the scarring. That gives us a rational way to pursue a more comprehensive improvement, not a guarantee of scar-free skin.
Patients often ask how many sessions it will take to remove their acne scars. I understand the question, but there's no honest number that applies to everyone.
Some scars improve substantially after a well-chosen release procedure. Other areas may benefit from repeated resurfacing or a second targeted treatment after the first result has settled. Collagen remodelling continues for months, so an early postoperative photograph can understate the eventual benefit—or exaggerate it while temporary swelling is present.
I think of acne-scar treatment as a series of carefully chosen, cumulative improvements. We address what is most limiting first, allow the skin to heal, reassess the remaining scars and decide whether another step is worthwhile.
Each treatment should have a clear purpose. More procedures aren't automatically better. There is no easy one-session fix for extensive, mixed acne scarring, and I would rather set that expectation honestly than promise that one impressive-sounding treatment will erase years of scarring.
Recovery depends on which components are used and how intensively they are performed.
Subcision may produce bruising, swelling and tenderness for several days or longer. PRP injections and filler can add temporary swelling or pinpoint bruising. Fractional CO2 resurfacing typically involves visible redness, peeling or crusting, and a more intensive session may require roughly one to two weeks before the skin looks socially presentable. Redness and changes in colour can persist beyond that, while remodelling continues over subsequent months.
I pay particular attention to patients with darker skin tones or a history of post-inflammatory hyperpigmentation, because aggressive resurfacing can leave unwanted pigment changes. Good pre-treatment assessment, careful settings and appropriate aftercare matter as much as the choice of device.
Before any combined procedure, we also review acne activity, previous scarring tendencies, medications, history of cold sores and medical factors that might affect healing. More intensive treatment needs to be justified by the expected benefit.
Usually not. Many depressed acne scars can be made significantly less noticeable, but complete removal or perfectly smooth skin is not a realistic promise. The goal is meaningful improvement in texture, contour and how visible the scars are in everyday light.
Neither is best for everyone. Fractional CO2 can be effective for textural scars and scar edges, but it generally involves more recovery and a greater risk of pigmentation changes than conventional microneedling. Microneedling can help selected scars, often over a series of treatments, but neither reliably releases deep tethering on its own.
Because a rolling scar may be held down by fibrous bands beneath the skin. Laser can remodel the surface, but it doesn't reliably sever those bands. Subcision addresses that deeper mechanical problem.
In my approach, carefully placed diluted hyaluronic acid filler provides subtle support in the space created by subcision. The intention is to reduce the chance that the released tissues re-adhere while healing and to improve the depressed contour. Clinical evidence supports subcision combined with filler, but prevention of re-tethering by this exact diluted technique has not been conclusively proven.
PRP may improve results when used alongside selected procedures, particularly fractional laser or microneedling, although studies are mixed and techniques vary. I use it as an adjunct to healing and remodelling, not as a standalone cure for established tethered scars.
That depends on the scar types, their depth, skin tone, treatment intensity and response to the first session. Many patients need more than one stage or treatment. The objective is to build meaningful improvement over time while avoiding unnecessary procedures.
Acne scars are difficult because they involve different changes in different layers of the skin. Some are tethered, some have lost volume, and others are primarily a problem of surface texture. Treating only one component can leave the others behind.
My preferred approach for selected mixed, depressed acne scars is to combine subcision to release tethered tissue, PRP to support remodelling, diluted filler to support the released space, and fractional CO2 resurfacing with Alma Hybrid to improve the overlying skin.
That stack isn't necessary for everyone, and it isn't a one-session promise. It's a way of matching each part of the treatment to a specific part of the problem, then building on the improvement as the skin heals.
If acne scars are affecting how you feel about your skin, I invite you to come in for an assessment at FORM Face + Body in Toronto. We'll look at the types of scars you have, discuss the options that actually address them and build a realistic plan for gradual, natural-looking improvement.
written by
Dr. Michael Brandt is a Royal College-certified Otolaryngology – Head and Neck Surgeon specializing in facial plastic and reconstructive surgery. He is fellowship-trained in facial plastic surgery and serves as an Assistant Professor at the University of Toronto, where he contributes to surgical education and research.
