Atheroma cysts are closed pockets filled with oil (sebum) and tiny keratin granules located behind the surface of the skin. Cysts formed due to blockage of oil glands in the skin can be cured with a small surgery or laser. Atheroma cysts are shaped like lumps or bumps, which often appear on the face, scalp, neck, or body. These cysts occur when the sweat glands or hair follicles become blocked. Small cysts are generally painless, but if they get bigger they can make the sensation uncomfortable, and sometimes they appear painful. You who often get pimples have a greater risk for experiencing atheroma cysts. Causes of atheroma cyst Atheroma cysts can form if the glands or oil passages (sebaceous glands) are damaged or blocked. This is what makes atheroma cysts also called sebaceous cysts. Sebaceous glands are glands that secrete an oil called sebum which functions to coat the skin and hair. The cause of the blockage and damage is a history of injury, such as surgical scars, scratc