Discolorations are not true scars but rather
post-inflammatory hyperpigmentation, which will fade over time.
Ice Pick Scars
Appearance: Ice pick scars are deep, very narrow scars that extend into the dermis. The skin looks as if it has been pierced by an ice pick or sharp instrument. Ice pick scars seem to make a small, deep "hole" in the skin. Some may look like a large, open pore.
Development: Ice pick scars develop after an infection from a cyst or other deep inflamed blemish works its way to the surface. Skin tissue is destroyed, leaving a long column-like scar.
Appearance: Boxcar scars are round or oval depressions with steep vertical sides. Wider than ice picks, boxcar scars give the skin a pitted appearance.
Development: When an inflammatory breakout destroys collagen, tissue is lost. The skin over this area is left without support, and a depressed area is created. Boxcar scars may be superficial to severe, depending on the amount of tissue lost.
Appearance: This type of scarring causes rolling or "wave-like" undulations across otherwise normal appearing skin.
Development: Rolling scars arise when fibrous bands of tissue develop between the skin and the subcutaneous tissue below. These bands pull the epidermis, binding it to deeper structures of the skin. It is this pulling of the epidermis from within that creates the rolling appearance of the skin.
Common treatments: Rolling scars are best treated with subcision.
Hypertrophic or Keloid Scars
Appearance: A hypertrophic scar looks like a raised, firm mass of tissue. These types of scars often grow larger than the original wound. Hypertrophic scars caused by acne are most often found on the torso, especially in men.
Development: Unlike ice pick or boxcar scars, hypertrophic scars are not caused by a loss of tissue. Rather, they develop because of an overproduction of collagen.
Common treatments: Steroid (cortisone) creams, tapes, or injections are used to help shrink and flatten the scar. Interferon injections are also used to soften scar tissue.
Alam M, Dover JS. "Treatment of Acne Scarring." Skin Therapy Letter. Dec 2006-Jan 2007; 11(10).
Goodman GJ, Baron JA. "The management of post-acne scarring." Dermatologic Surgery. Oct 2007; 33(10):1175-1188.
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.