Scalp atheroma is harmless and occurs when the outlet of a sebaceous gland has become blocked. It is difficult to say why some people are affected but it usually occurs in areas that are more densely covered with hair. As the gland produces sebum, over time a lump forms under the skin, a change that can be both cosmetically disturbing or irritating due to its location and size.
Common areas where atheroma occurs are
Scalp, torso, neck, face and abdomen. However, the cysts can occur over most of the skin. In some individuals, multiple atheromas occur for no known reason.
The name comes from the Greek word Athere, meaning porridge. It is due to the light-coloured, grainy mass of sebum that retreats as the atheroma grows.
Atheroma is a tumour that forms in the skin's sebaceous glands. It occurs when the skin becomes clogged and sebum cannot naturally escape. It builds up under the skin as a tumour, a sebaceous gland cyst. It is simply a benign cyst that contains sebum.
Appearance of Aterom
The skin over an atheroma is completely smooth and normal; on examination, one usually sees a soft, yellow, wide and slightly uneven lump in the skin with an oval marking that is anchored in the skin but is slightly displaceable. When touched, it feels 'springy and elastic' in texture. Some people can get multiple atheromas for no known reason. Most nodules are 2-4 mm in diameter, but they can be up to 5 cm in size.
Complaints and symptoms:
Usually when you get an atheroma, they tend to disappear over time. However, sometimes an atheroma can start to grow, become infected, red and tender. Patients sometimes choose to remove the cyst and it is important that the entire capsule surrounding the sebaceous content is removed, otherwise it can easily return. The cyst is removed using a local anaesthetic and is removed using a knife or laser, making it a relatively simple procedure. The cyst does not act like an abscess or pimple where you can open and squeeze out the contents and then it heals itself. If the doctor removes the entire capsule, the gland is gone forever. In exceptional cases, antibiotics are necessary and it is common for several stitches to be required.
This is how atheroma occurs
- Hair follicles are small sacs found throughout the skin that give rise to a hair. Sebaceous glands sit around the hair follicles and secrete an oil (sebum) that lubricates both the hair and the skin.
- If the oil does not come out, the gland clogs up and a lump forms under the skin, an atheroma.
- The atheroma is easily recognised and diagnosed by its appearance.
- Usually no treatment is needed but they can be removed if necessary.
- If the gland becomes inflamed, it may need to be emptied.
- Enlarged sebaceous glands are common among middle-aged and older people.
More on sebaceous glands:
Under our skin, we have sebaceous glands located outside the hair follicles, their job is to secrete an oil called sebum. The oil secreted in the follicle lubricates both the hair and the surrounding skin. The oil protects the skin and hair and makes them more 'waterproof'. Sebaceous glands are everywhere in the skin.