Inflamed acne blemishes are caused when the skin pores become overloaded with excess oil, dead skin cells and bacteria. The pore swells, which causes a break in the follicle wall. If the lesion is shallow, it usually heals quickly. However, if there is a deep break in the pore wall, infected material can spill out into the surrounding tissue and create a deeper lesion. The skin attempts to repair these lesions by forming new collagen fibers. These repairs are not as smooth and flawless as the original skin, resulting in acne scarring.
Almost 95% of patients with acne will experience some form of acne scarring. There are no specific risk factors, but some believe genetics plays a role.
There are two main types of acne scars:
Hypertrophic or keloid scarring are caused when the body produces too much collagen as acne wounds heal, resulting in a mass of raised tissue on the skin's surface.
Atrophic or depressed scarring develops when there is a loss of tissue. There are two common types of atrophic scarring. "Icepick" scars are usually small, yet obvious holes in the skin. "Boxcar" scars are depressed areas, usually round or oval in shape with steeply angled sides, similar to chickenpox scars.
A doctor will be able to diagnose a keloid or hypertrophic scar with an examination. The most common treatment for both keloids and hypertrophic scars is a cortisone steroid injection. It causes the keloid to lessen in size and the hypertrophic scar to disappear altogether. Cryosurgery and laser treatment are also available for keloids.
American Academy of Dermatology American Society for Dermatologic Surgery