The branchial cleft is a portion of the embryo in the womb that form the neck and collarbone during pregnancy. A branchial cleft abnormality or, more commonly, a “branchial cleft anomaly” is an irregularity that occurs during this development that results in malformations in the side of the neck, appearing anywhere from the ear, along the line of the jaw, to the base of the throat.
They can be either cysts (fluid-filled lumps under the skin), or fistulas (small pits or holes that may become infected and form an abscess). Branchial cysts usually appear as single, painless protrusions that are movable and compressible. They may appear in childhood or into adulthood.
Occasionally there is fluid leakage through the skin, and signs of infection may also be present. Treatment typically involves antibiotics, followed by whatever surgical options are indicated.