OPS-Code 5-203.71:

You had surgery on the mastoid process behind the ear. The procedure involved removing tissue from around your facial nerve.

There is a small bony projection on the head behind the ear. It contains small cavities full of air. You can feel this bony projection behind the ear.The mastoid process is the name given to the bony projection on the skull directly behind the ear. The cavities inside it are connected to the middle ear. Diseases of the middle ear can spread to the mastoid process via this connection. The middle ear is an air-filled cavity. It transmits sound to the inner ear in the form of sound waves.

Your mastoid process was hollowed out. This is normally done by removing the walls between the individual cavities using a surgical burr drill. This procedure converts the many small cavities in the mastoid process into one large cavity.

The facial nerve runs from both sides of the brain to different parts of the head. The nerve does different things. For example, it controls a lot of facial muscles. The nerve is also important for our sense of taste. It also affects our hearing and how much saliva and tears are formed.The facial nerve is located inside a canal in the skull bone. This canal runs directly alongside the inner ear, middle ear and mastoid process.

The facial nerve may become compressed inside its canal. For this reason, you had tissue removed from around the nerve – for example, parts of the bony canal. This is intended to give the nerve more space.