Acne scarring

The term ‘scarring’ refers to a fibrous process in which new collagen is laid down to heal an injury. It affects 30% of those with moderate or severe acne vulgaris. It is particularly common in 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.

Acne scarring

Colour changes

Inflammatory acne lesions that have recently healed may be followed by:

• Postinflammatory erythema - pink or purple flat patches
• Postinflammatory pigmentation - brown marks (pigmentation), seen in people who tan easily
• Postinflammatory hypopigmentation - white marks

Their appearance improves with time but it can take many months for them to go altogether.

Postinflammatory colour changes in acne

Pink marks

Brown marks

White marks

Treatment for postinflammatory pigmentation

Postinflammatory pigmentation may improve with:

• Careful sun protection - even though inflammatory acne lesions may improve, brown marks darken with sun exposure. Apply a broad-spectrum oil-free sunscreen.
• Azelaic acid cream - this reduces pigmentation as well as helping mild to moderate acne.
• Hydroquinone, an inhibitor of the enzyme causing tanning (tyrosinase) (see DermNet's page about melasma).
• Superficial chemical peels e.g. with glycolic acid or Jessner solution.

Persistent scarring

Unfortunately, true acne scars never completely disappear although they usually improve with time. They can be disguised with make-up.

The following types of scar occur in acne:

• Ice pick scars – these are pitted scars
• Atrophic scars – flat, thin scars or depressed scars (anetoderma)
• Hypertrophic or keloid scars – thick lumpy scars

Acne scarring

Ice-pick scars	Atrophic scars	Hypertrophic scars
Three lower images © Dr Ph Abimelec – dermatologue

Treatment for scarring

Ice pick scars:

• Dermabrasion
• Laser resurfacing
• Punch grafting for deep scars
• 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)

Atrophic scars:

• Soft tissue augmentation techniques such as hyaluronic acid, collagen, gelatin matrix & fat implants
• Dermabrasion
• Skin needling

Hypertrophic scars:

• Potent topical steroids for a few weeks
• Intralesional steroid injections
• Silicone gel dressings
• Skin needling
• Cryotherapy
• Surgical revision

Unfortunately, hypertrophic or keloid scars are particularly prone to recur even after apparently successful treatment.