- Acne scars form when blemishes such as pimples or cysts become inflamed and damage skin follicles
- They can cause atrophic and hypertrophic scars, and hyperpigmentation
- Treatment for acne scars depends on the type of scar, how severe it is and whether it’s painful or itchy
- Most acne scars are treated with lasers, microneedling, cryosurgery, or other procedures, while some raised scars can be treated with over-the-counter topical products
Just as there are different types of acne, there are different types of acne scars. Atrophic scars form when the edges of a blemish do not close up completely, leaving behind a depression in the skin. They include icepick, boxcar and rolling scars. Hypertrophic scars are raised scars that develop when the skin produces too much collagen while healing. Keloids are a severe type of hypertrophic scar.
Cysts and nodules that extend deep into the skin are most likely to cause scarring, but even a relatively minor blemish can leave a scar if it becomes infected or inflamed after being picked at or popped. Acne scarring also has a genetic aspect, so if you have a close family member who has acne scars you may be prone to scarring as well.
There are several ways to get rid of acne scars or make them less noticeable, from procedures that fill in or lift up atrophic scars to those that shrink or flatten hypertrophic ones.
How Do Acne Scars Form?
All acne blemishes, from minuscule blackheads to large cysts, are wounds. They occur when sebum (oil) and dead skin cells build up inside a hair follicle, rupturing the walls of the follicle and injuring surrounding tissue. When a blemish becomes infected and inflamed, the damage can be severe.
Acne scars form as part of the healing process from this damage as with a cut or scrape. A small acne blemish may be able to heal completely, but one that’s too wide for the edges to knit together seamlessly, such as a deep, inflamed cyst or nodule, typically will leave behind a scar.
Scar formation begins when the body produces granular tissue, a type of connective tissue designed to fill in areas of damaged skin.
Collagen and elastin are also produced during the healing process to replace damaged skin, as well as new capillaries that provide blood to the healing skin. This is why fresh scars tend to be pinkish.
Types of acne scars and how to recognize them
There are two types of acne scars as well as subtypes of each. If you have acne scars you’d like to treat, it can be helpful to know which type you have, as this will determine the most effective treatment.
Atrophic vs. hypertrophic acne scars
Acne scars that form depressions in the skin are called atrophic and fall under three subtypes: icepick, boxcar and rolling. They may be flesh-colored or pigmented, shallow or deep.
Raised scars are called hypertrophic. They tend to be smooth and pink or reddish and sometimes are itchy or painful. Keloids are a severe type of hypertrophic acne scar.
Atrophic Acne Scars
Each of the three subtypes of atrophic acne scars has a unique appearance:
- Ice pick acne scars make up 60–70% of atrophic acne scars. They’re very small and extend straight down into the skin, narrowing to a point
- Boxcar acne scars are wider than ice pick scars, round or oval in shape, and do not become narrower as they extend into the skin; they make up about 20–30% of atrophic acne scars
- Rolling acne scars are the largest and least common type of atrophic acne scar. They’re about the size of a pencil eraser and create areas of skin that appear to undulate, like a series of hills and valleys.
Most atrophic scars are flesh-colored, but some are hyperpigmented – darker than the surrounding skin or pinkish.
Treatments for atrophic acne scars
The goal of treating atrophic acne scars is to make them less noticeable by raising the depressed areas to be more level with the surrounding skin. There are many approaches to doing so.
- Surgery – Atrophic scars can be raised or broken up in one of two simple procedures performed in a dermatologist’s office; neither surgery will completely remove a scar, but both can make a depressed scar less noticeable
- Resurfacing – Scarred skin can be smoothed with a laser, chemical peel, dermabrasion or microdermabrasion; these procedures are most effective on scars that are relatively shallow
- Fillers – Individual boxcar and rolling acne scars can be plumped up with collagen or sometimes a person’s own fat tissue. Most fillers last 6–8 months, although some types may be permanent
- Radiofrequency (RF) skin tightening – Low-frequency energy waves are used to heat skin and stimulate production of collagen and elastin; it requires multiple treatments and is best for boxcar and rolling scars
- Microneedling – Involves running a roller studded with tiny needles over acne-scarred skin, creating minute punctures that stimulate collagen production as they heal; especially useful for large areas of scarring
Hypertrophic Acne Scars
Hypertrophic acne scars are raised scars that form when too much collagen is produced during healing. They’re pink and firm and stay within the boundaries of the damaged skin.
Keloids are a type of hypertrophic acne scar that can be especially unsightly. They tend to be reddish or purplish and extend past the boundaries of damaged skin.
Treatments for hypertrophic acne scars
Hypertrophic acne scars can be more complicated to deal with than atrophic scars because they are often itchy or painful, in addition to being unsightly. Treating hypertrophic scars may require a combination of procedures to address both issues.
- Injections. Some medications can soften and flatten scars when injected directly into the scar tissue. These include corticosteroids, fluorouracil (5-FU) and interferon, or a combination of 5-FU and corticosteroids. Several injections typically are needed to flatten a hypertrophic scar and provide pain relief
- Surgery. A raised scar can be treated with an in-office surgical procedure, usually followed by a series of injections or radiation
- Laser therapy. Lasers use light to flatten, fade and relieve hypertrophic scars. Pulsed dye laser therapy is one method and for light-skinned people, intense pulsed light (IPL) can be effective
- Cryosurgery. This procedure involves freezing scar tissue so it eventually dies and falls off and is sometimes combined with corticosteroid injections; this method noticeably lightens skin, so it’s not a good option for people with dark skin
- Topical products. These include creams, gels and silicone bandages, all of which can be bought over the counter. While not as effective at improving the appearance of raised scars, they can reduce their appearance and relieve pain and itching when used continuously
When to see a doctor
Most acne scars are more nuisance than medical concern, but they can have a direct effect on your psychological health, well-being and quality of life. If you have acne scars that make you self-conscious about your appearance or cause discomfort, see a dermatologist. They can examine your scars and determine which treatment or combination of treatments are best for you.
It’s also important to see a doctor if you have severe or persistent acne, especially if you have blemishes that are deep or inflamed or there’s a history of acne scarring in your family. Treating acne that has the potential to cause scars proactively can greatly reduce the risk of developing them or at least minimize their appearance.
Be aware most insurance providers regard acne scar treatment to be cosmetic, which means you’ll have to pay out of pocket for any procedures you have.
There are two types of acne scars: atrophic (depressed) and hypertrophic (raised). Many professional treatments and over-the counter products are available to address the specific characteristics of each and to eliminate or reduce their appearance.
If you have acne, it’s important to not pick, squeeze, or pop acne blemishes. Even a minor one can become infected and inflamed enough to damage the hair follicle and create a scar.
To lower the risk of scarring, see a dermatologist as soon as you begin having recurrent or severe breakouts. It is important to adhere to your treatment regimen for best results.
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