What is acne scarring?
The term "scarring" refers to a fibrous process in which new collagen is laid down to heal a full-thickness injury. It affects 30% of those with moderate or severe acne vulgaris. It is particularly common in nodulocystic acne, acne conglobata and acne fulminans. It may also be a long-term consequence of infantile acne.
To reduce the chance of scarring, seek treatment for your acne early. Severe acne can often be cured.
What are postinflammatory colour changes?
Postinflammatory colour changes are seen after inflammatory acne lesions have recently healed.
- Postinflammatory erythema – pink or purple flat patches
- Postinflammatory pigmentation – brown marks (pigmentation), seen in people who tan easily
- Postinflammatory hypopigmentation – white marks
Postinflammatory colour changes improve with time, but it can take many months for them to completely resolve.
What is the treatment for postinflammatory pigmentation?
The treatment for postinflammatory pigmentation includes:
- Careful sun protection – even though inflammatory acne lesions may improve, brown marks darken with sun exposure. Apply a broad-spectrum oil-free sunscreen and wear a broad-brimmed hat when outdoors
- Azelaic acid cream – this reduces pigmentation as well as effectively treating mild to moderate acne
- Hydroquinone bleaching creams – these inhibit the enzyme tyrosinase that causes tanning (see melasma)
- Superficial chemical peels containing glycolic acid or Jessner solution
What are the features of persistent scarring?
Unfortunately, true acne scars never completely disappear, although their appearance usually improves with time. They can be disguised with make-up (cosmetic camouflage).
The following types of scar occur in acne:
- Ice-pick scars – these are deep, narrow, pitted scars
- Rolling scars – broad depressions with sloping edge
- Boxcar scars – broad depressions with with sharply defined edges
- Atrophic scars – flat, thin scars or depressed scars (anetoderma)
- Hypertrophic or keloid scars – thick lumpy scars
|Rolling scars||Three images © Dr Ph Abimelec – dermatologue|
How do you treat acne scars?
Ice pick and boxcar scars
- Laser resurfacing
- Punch grafting for deep scars
- TCA CROSS (Chemical Reconstruction Of Skin Scarring) uses precisely placed 50–100% trichloracetic acid
- Subcision®: a surgical technique in which the fibrous band under the scar is divided, allowing the skin to return to its normal position
- Larger scars can be excised (cut out) and the defect closed to form a scar in a thin line
Atrophic and rolling scars
- Soft tissue augmentation techniques such as hyaluronic acid, collagen, gelatin matrix and fat implants
- Skin needling
- Laser resurfacing (Er:YAG and ablative fractional lasers)
- Potent topical steroids applied under occlusion to the scar for a few weeks
- Intralesional steroid injections into the body of the scar
- Silicone gel dressings applied for 24 hours a day continously for some months
- Skin needling
- Cryotherapy (freezing)
- Surgical revision
Unfortunately, hypertrophic or keloid scars are particularly prone to recur even after apparently successful treatment.