Glossary
| March 1, 2007
Glossary
actinic keratosis: Scaly pink or red-brown raised spots or patches caused by overexposure to the sun. Actinic keratosis may be a precursor to skin cancer.
aesthetician: Licensed skin care professional who performs procedures including deep cleansing, low-grade chemical peels, microdermabrasion, and postsurgical skin care.
alpha hydroxy acids: Fruit-derived acids used in creams and lotions to act as exfoliants.
autologous fat transplant: Removal of fat from one part of the body to use as filler in another part, for example, to fill wrinkles and lines in the face and lips.
basal cell carcinoma: The most common skin cancer. Basal cell carcinoma doesn't spread to internal organs.
Botox: Brand name for a substance made of botulinum toxin A that eases the appearance of some facial wrinkles by paralyzing the underlying muscles.
chemical peel: Use of mild to caustic chemical solutions to wound the outer layer of the epidermis and encourage new collagen growth.
collagen: A fibrous protein that's the main component of connective tissue.
dermis: Middle layer of skin that contains blood and lymph vessels, nerves, hair follicles, and glands that produce sweat and oil.
elastin: The protein that gives skin its elasticity.
epidermis: The outermost layer of skin.
fibroblasts: Cells in the skin that secrete collagen.
hirsutism: Excess hair growth, often caused by hormonal imbalances.
humectant: An agent used in moisturizers; binds water to the skin to promote hydration.
intense pulsed light (IPL): White light that's used in skin-resurfacing procedures and hair removal.
keratinocytes: Cells of the epidermis that produce a tough protein called keratin and form a soft, protective sheet for the body.
Langerhans cells: Cells of the immune system that work in the skin to fight infection.
laser: A word derived from the acronym of "light amplification by the stimulated emission of radiation." Lasers produce intense beams of light that generate heat used in surgery, removal of pigmented lesions, and skin rejuvenation.
melanocytes: Cells located deep in the epidermis that produce melanin, the pigment that colors skin.
melanoma: The most serious type of skin cancer, originating in the pigment-producing cells known as melanocytes.
photodynamic therapy: A treatment for actinic keratosis that uses light exposure to activate a therapeutic agent.
skin resurfacing: Improving skin texture, tone, wrinkle appearance, and discolorations by promoting new collagen growth. Chemical peels, dermabrasion, microdermabrasion, and laser procedures are skin-resurfacing techniques.
squamous cell carcinoma: A common skin cancer, rarely fatal, that can spread to the lymph nodes and internal organs.
stratum corneum: The most superficial layer of the epidermis.
subcutaneous tissue: The deepest layer of skin, which consists of connective tissue and fat.
Review Date: 2007-03-01
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