Overview

Mastoidectomy is an operation to remove infected tissue from the middle ear and air-filled spaces in the mastoid bone. These cells develop in the mastoid bone a honeycomb-like structure that sits just behind the ear, at the base of the temporal bone.¹

The procedure is recommended when an ear infection spreads to the skull. This procedure is performed to treat many conditions, including mastoiditis and cholesteatoma.^2,3,4

Mastoidectomy may also be performed during cochlear implant surgery and ruptured eardrum repair. It may also be used to treat chronic ear infections and prevent serious complications. 

Mastoid bone

The mastoid process is a cone-shaped bony projection at the base of the temporal bone, which is situated behind the ear. It’s surface connects several head and neck muscles, and these muscles help with chewing, swallowing and speech. The occipital groove, in the mastoid process contains the occipital artery, which provides blood to the neck muscles.

Functions

The mastoid process (bone) has muscles attached that support the movement of the head and neck. Some of the muscles involved include: 

• Sternocleidomastoid muscle: Muscle attached to the mastoid bone, one end is attached to the sternum (breast bone) and the other end to the clavicle (collarbone). This supports the head movement of rotation, from the right to the left side⁵
• Posterior auricularis muscle: Muscle that is responsible in moving the ear and scalp
• Splenius capitis muscle: Muscle that assists in supporting the head in the erect position
• Digastric muscle: Muscle that can produce forces which open the jaw and wiggle it from side-to-side, and is responsible for actions such as speaking, chewing, swallowing, and breathing
• Longissimus capitis muscle: Muscle extends and hyperextends head, and acting unilaterally, flexes and rotates the head

Mastoid bone

The mastoid process is a cone-shaped bony projection at the base of the temporal bone, which is situated behind the ear. Its surface connects several head and neck muscles, and these muscles help with chewing, swallowing and speech. The occipital groove, in the mastoid process contains the occipital artery, which provides blood to the neck muscles.

Functions

The mastoid process (bone) has muscles attached that support the movement of the head and neck. Some of the muscles involved include: 

• Sternocleidomastoid muscle: Muscle attached to the mastoid bone, one end is attached to the sternum (breast bone) and the other end to the clavicle (collarbone). This supports the head movement of rotation, from the right to the left side⁵
• Posterior auricularis muscle: Muscle that is responsible for moving the ear and scalp
• Splenius capitis muscle: Muscle that assists in supporting the head in the erect position
• Digastric muscle: Muscle that can produce forces which open the jaw and wiggle it from side-to-side, and is responsible for actions such as speaking, chewing, swallowing, and breathing
• Longissimus capitis muscle: Muscle extends and hyperextends head, and acting unilaterally, flexes and rotates the head

Conditions causing mastoidectomy

• Ear infection (acute otitis media): A sudden onset infection caused by a virus or bacteria that affects the middle ear, the air-filled space between the eardrum and the inner ear. It causes inflammation and builds up fluid behind the eardrum. The middle ear transmits sound vibrations from the eardrum and the inner ear and enables a person to hear⁶
• Chronic otitis media: Chronic middle ear infection that lasts more than 3 months, that doesn’t resolve or reappears repeatedly⁷
• Mastoiditis: Bacterial infection affecting the mastoid bone and middle ear infection. It was once a common serious illness causing death in young children. Nowadays antibiotics treat the infection and mastoiditis has become a very rare condition. People still can develop mastoiditis if the middle ear infection is left untreated. Healthcare providers use antibiotics to treat this condition, but in severe cases, surgery maybe suggested³ 
• Cholesteatoma: A condition caused by a non-cancerous growth that forms behind the eardrum. It develops when dead skin cells gather behind the eardrum and form a lump which looks like a cyst. It may also occur due to a ruptured eardrum. This condition can cause pungent discharge from the ear, dizziness, and a feeling of fullness in the ear and can lead to hearing loss or tinnitus⁴

Symptoms of ear infection

• Pain at the mastoid bone
• Redness and swelling in the area affected
• Fever
• Headache
• Ear drainage
• Irritability
• Smelly discharge (pus)
• Dizziness
• Feeling fullness in the ear

Mastoidectomy

Mastoidectomy is an operation to remove infected tissue from the middle ear and air filled spaces in the mastoid bone. These cells form in the honeycomb-like structure of the mastoid bone that sits just behind the ear, at the base of the temporal bone.¹

The operation is performed by an Ear Nose and Throat surgeon who is a specialist in this fields. The surgery is performed under general anaesthesia.²

Procedure

• Mastoidectomy: The surgeon makes an incision (cut) behind the ear to access the mastoid bone. They use special instruments to open the mastoid bone and remove the infected air cells. Then the surgical site is sutured (stitched together) and a dressing is applied to the wound. The surgical incision may feel sore and the ear may feel full. Pain relief may be prescribed such as acetaminophen or ibuprofen. This is known as a simple mastoidectomy.
• A canal wall-up mastoidectomy or tympanomastoidectomy: In this procedure, the surgeon removes more bone than a simple mastoidectomy. This gives the surgeon access to the middle ear space behind the eardrum. In this procedure, the ear canal is left completely intact
• A canal wall down mastoidectomy or tympanomastoidectomy: This procedure is done when the disease has damaged the ear canal and removal of the ear canal is required to completely irradicate disease, and ensure that the mastoid cavity is clean in the future

Complications of mastoidectomy

• Prevent chronic ear infection or reoccurrence of the same
• Loss of hearing 
• Vertigo: It can occur due to a lot of health conditions. Vertigo is a sensation where the person feels the environment is spinning around in a circle and this makes the person dizzy and off balance¹¹
• Dizziness
• Facial nerve damage⁸
• Labyrinthitis: Caused by inflammation of the labyrinth. The labyrinth helps in maintaining balance and proper hearing⁹
• Meningitis: Condition occurs when the meninges that surround the brain and the spinal cord are inflamed and infected with pathogens. It can cause headache, fever and stiff neck¹⁰
• Brain abscess
• Facial nerve injury or paralysis
• Dysgeusia: Condition in which the sense of taste is different. People taste food as sweet, sour, bitter or metallic¹²
• Tinnitus: Condition by which where a person hears a ringing noise in the ears without any external sound

FAQ’s

Is mastoidectomy a major surgery?

Yes, mastoidectomy is a major operation undertaken under general anaesthesia. The complications are usually minor.

Does hearing improve after mastoidectomy?

The main reason to undertake this procedure is to remove the infection affecting the mastoid bone and to prevent the infection from spreading to the skull. Hearing loss is common in canal wall up or canal wall down mastoidectomy. 

How painful is mastoidectomy?

Mastoidectomy is done under general anaesthesia, so the patient will not feel any pain during the procedure. After the anaesthesia is worn off the patient may feel sore at the incision site and feel like the ear is full. 

How long is the hospital stay for mastoidectomy? 

Usually, mastoidectomy takes place in 3 - 4 hours. The patient can go home on the same day of the surgery if it is a simple mastoidectomy. For canal wall up or canal wall down mastoidectomy, the patient will stay overnight and be discharged the next day.

Can mastoiditis affect the brain?

Untreated bacterial infection can continue to affect the skull and spread through the blood to the organs including the brain.

Summary

Mastoidectomy is a surgical procedure that removes infected cells affecting the mastoid bone, and that has spread from the middle ear. These diseased mastoid air cells form in the hollow spaces of the mastoid bone. This procedure is necessary when an ear infection spreads to the skull. It is performed for a number of conditions, especially mastoiditis and cholesteatoma. The risks and benefits of this procedure can provide people with an improved quality of life, free from pain and long-lasting symptoms.