Mastoidectomy Explained: How Surgeons Clear Infected Mastoid Air Cells Behind the Ear

The scan is still glowing on the monitor when the surgeon turns it toward you. A gray smudge sits where the bone behind your ear should look like lace. You came in about a stubborn, sour-smelling trickle from one ear and a phone you kept switching to the other side. You leave with a word you have never heard before and a decision to make.

For parents, the version is different but the feeling is the same: a toddler with a fever whose ear has started to stick out, a pediatric team talking about intravenous antibiotics, and the possibility of an operation if the swelling does not settle.

Either way, the mastoidectomy procedure is what the conversation circles back to. It is one of the oldest operations in ear surgery and one of the least understood by the people who need it. This article walks through what the mastoid is, why it gets sick, what actually happens in the operating room, and what the weeks afterward tend to look like, with the evidence stated plainly and the decisions left where they belong: with you and your care team.

What is a mastoidectomy procedure, and why would anyone need one?

Press a finger behind your earlobe and you will feel a firm knob of skull. That is the mastoid. From the outside it seems solid, but inside it is a honeycomb of small air-filled pockets called mastoid air cells, all connected to the middle ear through a narrow passage. Those pockets are lined with the same thin membrane that lines the space behind the eardrum. An infection that begins behind the eardrum therefore has a direct road into the bone.

A mastoidectomy procedure removes diseased air cells and whatever is filling them, whether that is pus, thickened inflamed tissue, or a cholesteatoma, which is a pocket of trapped skin that slowly erodes bone. The surgeon opens the mastoid, clears the disease down to healthy bone, and leaves a smooth, well-ventilated surface that can heal.

Three situations account for nearly all mastoidectomies. The first is mastoiditis, an infection of the mastoid bone that usually follows a middle ear infection and that, according to MedlinePlus, may need surgery when antibiotics alone do not control it. The second, and the most common reason in adults, is cholesteatoma. The third is access: when a surgeon needs a safe pathway to the inner ear, for example to place a cochlear implant, the Mayo Clinic describes a mastoidectomy as part of that operation. Some people with a chronically discharging ear that has resisted drops and cleaning are also offered it.

One point matters more than any other and is worth stating early. The primary aim of the operation is a safe, dry ear that no longer threatens the structures around it. Hearing is a separate goal. It is often addressed at the same sitting or later, but it is not what the drill is there for.

How serious is mastoiditis, and when does it lead to surgery?

Mastoiditis sits in an awkward place in modern medicine. It is far less common than it was before antibiotics, yet it has not disappeared, and the reason it still commands attention is geography. The mastoid shares thin walls with the lining of the brain above it, a large vein called the sigmoid sinus behind it, the facial nerve running through it, and the delicate inner ear beside it. Infection that breaks through any of those walls stops being an ear problem.

MedlinePlus describes mastoiditis as a complication of a middle ear infection, more often seen in children, and lists among its possible complications meningitis, brain abscess, facial paralysis, hearing loss and dizziness. Cleveland Clinic and Johns Hopkins describe the same pattern: pain, tenderness and swelling behind the ear, sometimes with the ear pushed outward, developing in someone who already has an ear infection.

Treatment usually begins with intravenous antibiotics in hospital. A clinician may also make a small opening in the eardrum, called a myringotomy, to let infected fluid drain and to send a sample to the laboratory, which helps the prescribing team match the antibiotic to the organism. Which drug, and for how long, is a decision for that team based on the culture result and the child’s or adult’s response.

Surgery enters the picture when the infection is not settling on antibiotics, when a scan shows an abscess under the skin or inside the bone, or when a complication has already developed. In those cases, MedlinePlus notes that a mastoidectomy may be performed to drain the infection and remove diseased bone. For a frightened family, the useful framing is this: mastoiditis is serious because of its neighbors, and the operation exists precisely to keep those neighbors safe.

What is cholesteatoma, the most common reason adults have a mastoidectomy?

The name misleads on two counts. Cholesteatoma has nothing to do with cholesterol, and despite the tumor-like ending it is not a cancer. MedlinePlus defines it as an abnormal collection of skin cells that grows in the middle ear, behind the eardrum. The NHS describes it as a growth of skin that is rarely dangerous in itself but can damage the delicate structures inside the ear if left to expand.

Most cholesteatomas begin as a retraction pocket. When the tube that ventilates the middle ear works poorly, negative pressure sucks part of the eardrum inward until it forms a pouch. Skin sheds constantly, and inside a pouch that shed skin has nowhere to go. It accumulates, becomes infected, and releases enzymes that dissolve bone. Others form after a perforation lets skin migrate inward, and a small number are present from birth.

The damage is slow but relentless. The three tiny hearing bones are often the first casualty, which is why muffled hearing and a recurring, unpleasant-smelling discharge are the complaints that bring most people to the clinic. Left alone, the pocket can erode the thin plate of bone protecting the facial nerve, breach the inner ear, or wear through the roof of the middle ear toward the brain lining.

Here the evidence is unusually clear. The NHS states that surgery is the only way to remove a cholesteatoma. There are no drops, tablets or lasers that dissolve it, and cleaning in clinic only manages the surface. The operation to remove it usually involves opening the mastoid, because the pocket so often extends into those air cells, which is why cholesteatoma and mastoidectomy are discussed in the same breath.

What happens during the mastoidectomy procedure, step by step?

The operation begins weeks before the anesthetic, with imaging. A CT scan of the temporal bone, the section of skull that houses the ear, gives the surgeon a map of how far the disease extends, how thick the roof of the middle ear is, and where the facial nerve runs. Some people also have an MRI, particularly when the question is whether a cholesteatoma has returned after earlier surgery.

On the day, you receive a general anesthetic, so you are fully asleep. Many surgeons place small electrodes on the face connected to a facial nerve monitor, a device that sounds an alert if the nerve is stimulated during drilling. The incision is usually made in the crease behind the ear, where it hides well, although some parts of the operation may be done through the ear canal with an endoscope, a thin camera.

Working under a microscope, the surgeon uses a high-speed drill with continuous water irrigation to remove bone in thin layers. The mastoid is opened cell by cell until a set of landmarks appears: the roof of the cavity, the wall covering the sigmoid sinus, the bony bump of the lateral semicircular canal that marks the inner ear, and the facial nerve. Everything diseased between those landmarks is removed.

If the eardrum is perforated or the hearing bones are eroded, the surgeon may repair them at the same time, a step called tympanoplasty, often using a sliver of the patient’s own tissue harvested from behind the ear. The ear canal is then packed with dissolvable or removable dressing, the incision is closed, and a bandage is wrapped around the head. You wake in recovery with a pressure dressing, a dull ache, and an ear that will sound blocked until the packing comes out.

Which type of mastoidectomy will I have? Canal wall up versus canal wall down

Mastoidectomy is a family of operations, not a single one, and the version you are offered depends on how far the disease has spread and how much bone is already gone. The central fork in the road is the bony wall of the ear canal. Keeping it preserves normal anatomy; removing it creates a single large cavity that is easier to inspect for life. A canal wall down mastoidectomy is the term for the second approach.

Type	What is removed	Typically used for	Main trade-off
Simple (cortical)	Diseased mastoid air cells only; middle ear and canal wall untouched	Acute mastoiditis not settling on antibiotics; access for cochlear implant	Limited view of the middle ear
Canal wall up (intact canal wall)	Mastoid cells plus disease in the middle ear, with the canal wall kept	Cholesteatoma where anatomy can be preserved	Hidden areas remain, so a second look or MRI is often needed
Canal wall down (modified radical)	Mastoid cells plus the canal wall, creating one open cavity, eardrum rebuilt	Extensive cholesteatoma, revision surgery, poor ventilation	Lifelong cavity care and water precautions
Radical	As above, but the middle ear is not reconstructed	Rare; severe disease where hearing cannot be preserved	Maximum safety, minimal hearing

Neither of the two main approaches is universally better. Canal wall up keeps the ear looking and behaving normally, but because cholesteatoma can hide behind preserved bone, the NHS notes that a further operation or scan within about a year is often planned to check nothing remains. Canal wall down makes any recurrence visible in clinic and lowers the odds of a hidden pocket, at the cost of a cavity that needs periodic cleaning and a lifetime of keeping water out. Surgeons weigh the extent of disease, the condition of the other ear, and how reliably a person can attend follow-up before choosing. It is reasonable to ask which one is planned and why.

Is mastoidectomy major surgery?

People ask this for two reasons: to gauge the danger and to gauge the disruption. The honest answer splits along the same line.

In terms of what is at stake, yes, this is major surgery. It is performed under general anesthesia, it involves drilling bone within a few millimeters of the facial nerve, the inner ear, a major vein and the lining of the brain, and it demands the kind of precision that is why ear surgeons train for years to do it. The seriousness lies in the neighborhood, not the size of the incision.

In terms of disruption to your body, it is less dramatic than the word major suggests. The incision is a few centimeters long and hidden behind the ear. Blood loss is usually small. The NHS advises that people having surgery for cholesteatoma may go home the same day or stay one night in hospital. There is no large wound to nurse, no drain to manage at home, and most people are walking around the ward within hours of waking.

What surprises many is the sensory strangeness rather than the pain. The operated ear feels stuffed with cotton because it is packed. Chewing can be tender. Some people notice a metallic taste on one side of the tongue for a while, because a small taste nerve runs through the operating field. Mild unsteadiness for a day or two is common as the inner ear settles.

So: major in significance, moderate in recovery, and routine in the hands of a team that does it regularly. Whether it is the right choice for your ear is a separate question, and one your surgeon should answer against the alternative of leaving the disease where it is.

Who is usually offered a mastoidectomy, and who is asked to wait?

Surgeons think about this operation in terms of threat. The stronger the threat to hearing, balance, the facial nerve or the brain, the more clearly surgery is recommended. Several groups fall squarely on the offered side.

Anyone with a confirmed cholesteatoma is usually advised to have it removed, at any age, because the NHS is clear that it will not go away on its own and tends to enlarge. People with acute mastoiditis who develop an abscess, show signs of a complication, or fail to improve on intravenous antibiotics are typically offered surgery promptly, as MedlinePlus describes. Those with a chronically infected, discharging ear that has not responded to months of drops and clinic cleaning may be offered it to achieve a dry ear. And people receiving a cochlear implant have a mastoidectomy as part of the access route, per the Mayo Clinic.

Other people are asked to wait, or offered something different first. A child with early mastoiditis who is clearly improving on antibiotics is usually observed rather than operated on. An ear with an active, wet infection may be treated with antibiotic drops and cleaning for a period beforehand, because operating on inflamed tissue is harder and bleeds more; the choice and duration of any drops sits with the prescribing clinician. Someone whose other ear has no useful hearing will have a much longer conversation, because any risk to the operated ear carries higher stakes. A frail older adult with a small, stable cholesteatoma may be offered regular clinic cleaning and monitoring instead of an anesthetic.

None of these are rules. They are the considerations a treating team weighs, and the final recommendation should be explained to you in terms of your ear, your scan and your health, not a general category.

What are the risks of mastoidectomy surgery?

Every consent conversation for this operation covers the same short list, and it is worth understanding why each item is on it rather than simply hearing it read aloud.

Hearing can change in either direction. Removing a cholesteatoma that was bridging a gap between eroded hearing bones can leave hearing temporarily worse until reconstruction is done or heals. Less commonly, the inner ear itself is affected, causing a permanent loss in that ear; the NHS lists hearing loss among the possible complications. Tinnitus, a ringing or buzzing, may appear or change for the same reason.

Dizziness is common for a few days as the inner ear settles after nearby drilling, and it usually fades. Persistent vertigo is uncommon and prompts review.

Facial weakness is the risk people fear most. The facial nerve travels through the mastoid on its way to the muscles of expression. Nerve monitoring and careful drilling exist to protect it. Temporary weakness from swelling or local anesthetic is more likely than permanent injury, which the NHS describes as rare.

Taste disturbance on one side of the tongue can follow stretching or division of a small nerve, the chorda tympani, that crosses the middle ear. It often improves over months.

Rarer events include leakage of the fluid that surrounds the brain if the thin roof of the cavity is breached, wound infection, bleeding, and numbness of the outer ear from the incision.

Finally, cholesteatoma can be left behind or come back. The NHS notes it can return and that long-term follow-up, sometimes including further surgery, is needed. Hearing these risks is not a reason to refuse surgery; it is the information that lets you compare them with the risks of leaving the disease alone.

Are there alternatives to mastoidectomy?

Alternatives exist, but they depend entirely on what is wrong, and the most common condition has none that work.

For acute mastoiditis, the first-line treatment is not surgery at all. Intravenous antibiotics, chosen by the treating team and adjusted once laboratory cultures return, control many cases, and a myringotomy to drain the middle ear may be added. MedlinePlus lists surgery as the step taken when these measures do not control the infection or when an abscess forms. Watchful, hour-by-hour observation in hospital is therefore a genuine alternative for the child who is improving.

For a chronically discharging ear without cholesteatoma, medical management may be tried first: careful suction cleaning in clinic and courses of antibiotic ear drops, which work by delivering the drug directly to the infected lining. Some ears become dry this way and stay dry. Others relapse whenever water gets in or a cold arrives, and at that point surgery to remove diseased mastoid cells and repair the eardrum may be offered as a more durable fix.

For cholesteatoma, the position is different. The NHS states plainly that surgery is the only way to remove it. Clinic cleaning can keep a small pocket tidy and delay problems, and some people who are unfit for anesthesia or who decline surgery choose this path with close monitoring. That is a legitimate choice as long as everyone understands it manages the pocket rather than treating it, and that erosion continues underneath.

Hearing aids deserve a mention only to set them aside. They amplify sound; they do nothing to a pocket of skin eroding bone. What they can do is help after surgery, once the ear is safe, if a hearing gap remains. Ask your team which of these paths applies to your ear, and why.

How long is recovery from mastoidectomy? A realistic mastoidectomy recovery time

Recovery unfolds in layers, and knowing the order helps. The timings below are typical ranges drawn from NHS guidance on cholesteatoma surgery; your team’s instructions override them.

The first two days are about the dressing. A firm bandage around the head usually comes off within a day or two. There is a steady ache behind the ear that the team manages with pain relief they prescribe, and the ear feels blocked because it is packed. Mild unsteadiness is common. You are encouraged to walk, eat lightly and sleep with the head slightly raised.

The first week is about protection. The NHS advises taking about a week off work or school. Keep the ear completely dry, which in practice means a cotton ball coated in petroleum jelly in the outer ear during showers and no hair washing over the ear until cleared. Sneeze with your mouth open, avoid blowing your nose, and skip heavy lifting or straining, all of which push pressure into the healing middle ear.

Weeks two to six are about the packing. Depending on the material used, it either dissolves or is removed at a clinic visit, and hearing often improves noticeably at that point. Some people are prescribed antibiotic drops for a period; follow the prescriber’s instructions rather than a general rule. The NHS advises avoiding swimming and flying until your surgeon says it is safe, which is often a few weeks, and the same caution applies to strenuous exercise.

Months, not weeks, are the timescale for the final result. Scars fade, taste changes settle, and the true hearing outcome becomes clear once the ear is fully healed. If you had a canal wall up operation, the NHS notes a check operation or scan is often planned within about a year.

What is life like after mastoidectomy? Hearing, water and the mastoid bowl

Most people who have had this operation describe the same relief: the ear stops leaking. After years of a damp pillow and a hand cupped over the ear in the shower, a dry ear changes small daily habits in ways that are hard to appreciate until they arrive. Life after mastoidectomy is, for most, quieter in every sense.

Hearing is more variable, and honesty here matters. If the disease had already destroyed the hearing bones, removing it does not bring them back; reconstruction may be attempted at the same time or in a later operation, and its results depend on how much healthy tissue remains. If hearing was preserved and the eardrum repaired well, many people notice improvement once the packing is gone. Some end up with a fixed gap that a hearing aid fills well, now that the ear is safe to wear one in. A permanent inner ear loss is uncommon but real, which is why it appears on the consent form.

The biggest lifestyle difference depends on the type of operation. After a canal wall up procedure, the ear canal looks normal and, once healed, often needs few special precautions beyond follow-up. After a canal wall down procedure, you have what surgeons call a mastoid bowl: a single open cavity that collects wax and dead skin and cannot clean itself. It needs suction cleaning in clinic, typically at intervals your surgeon sets, and water in the bowl tends to cause infection, so custom swimming plugs or a lifelong habit of keeping the ear dry become normal.

Follow-up is long. The NHS notes cholesteatoma can return years later, so clinic reviews or MRI surveillance continue well beyond the point when the ear feels forgotten. Most people fold this into life the way they fold in a dental check.

What people often get wrong about mastoidectomy

The myths around this operation tend to make people either far more frightened or far more casual than the evidence supports. A few deserve correcting.

It is brain surgery. No. The mastoid sits beside the brain lining, and surgeons treat that wall with great respect, but the operation is confined to the bone of the ear. Confusing proximity with entry inflates fear.

It will fix my hearing. Not necessarily, and sometimes not at all. The operation’s purpose is a safe, dry ear. Hearing depends on what the disease has already eroded and on whether reconstruction is possible. Anyone promising a specific hearing result is promising something the evidence does not support.

Cholesteatoma is a tumor. It is skin in the wrong place, not a cancer, and MedlinePlus is explicit on this. It does not spread to other organs. It does erode bone, which is why it still needs removing.

Drops or antibiotics can clear a cholesteatoma. They can reduce infection on its surface. The NHS states that surgery is the only way to remove the pocket itself.

Mastoiditis is a thing of the past. It is much rarer than before antibiotics, but MedlinePlus and Cleveland Clinic both still describe it as a real complication of ear infections, particularly in children, and its neighbors have not moved.

Once operated, it is finished. Cholesteatoma can recur, and the NHS describes long-term follow-up as standard. Skipping the check scan or second-look operation because the ear feels fine is one of the more common ways a small problem becomes a large one.

Everyone ends up with a cavity to clean. Only canal wall down operations leave a mastoid bowl. Many people have a canal wall up procedure and an ear that looks and behaves normally.

Questions to ask your care team before a mastoidectomy

A good consultation leaves you knowing not just that you need surgery but why this operation, in this form, now. These questions tend to open that conversation. Write the answers down; the details blur quickly.

• What exactly did the CT scan show, and how far does the disease extend into the mastoid?
• Are you planning a canal wall up or a canal wall down operation, and what made you choose that approach for my ear?
• Will you repair the eardrum or the hearing bones at the same time, or is that a separate stage?
• What is my hearing like now in this ear and in the other one, and what range of hearing outcomes should I realistically expect?
• Will facial nerve monitoring be used during the operation?
• What is the plan if you find the disease is more extensive than the scan suggested?
• How will I know whether cholesteatoma has been left behind, and will that be checked with a second operation or an MRI?
• How long should I expect to be in hospital, and who do I contact if something worries me after I go home?
• What specific water and flying precautions apply to me, and for how long?
• If I end up with a mastoid bowl, how often will it need cleaning, and where?
• What would happen if I chose not to have surgery, or to delay it?
• Are there features of my general health that change the risks for me?

Notice that none of these ask the surgeon to promise a result. They ask for the reasoning, the plan and the safety net. A team that answers them clearly is giving you what you need to consent with your eyes open, and to recognize early when something is not going to plan.

When to call your doctor after a mastoidectomy or with a suspected mastoid infection

Two situations call for a prompt phone call rather than waiting for the next appointment: a new or worsening ear infection that might be reaching the mastoid, and a recovery after surgery that stops behaving normally.

Before any surgery, MedlinePlus and Johns Hopkins describe the picture that should prompt urgent assessment in someone with an ear infection: increasing pain, swelling or redness over the bone behind the ear, an ear that begins to stick out, high or persistent fever, or a child who becomes unusually drowsy or irritable. In an adult or child, new severe headache, a stiff neck, confusion, weakness on one side of the face, or sudden severe dizziness alongside an ear infection are emergency signs, because they can indicate that infection has spread beyond the bone. Seek emergency care rather than a routine appointment.

After surgery, most days are uneventful, and a little blood-tinged fluid on the dressing in the first day or two is expected. Contact your surgical team the same day if you notice any of the following:

• Bleeding that soaks through the dressing or does not stop with gentle pressure.
• Increasing pain, redness, heat or swelling around the incision, or the wound opening.
• Fever, or foul-smelling discharge from the ear canal after the first few days.
• New weakness of the face on the operated side, including difficulty closing the eye or a drooping mouth.
• Severe or worsening dizziness, vomiting, or a sudden change in hearing.
• Clear, watery fluid dripping steadily from the ear or nose, especially when leaning forward.
• Severe headache, neck stiffness, confusion or unusual sleepiness.

Your discharge paperwork should include a direct number for the ward or clinic. Use it. Surgical teams would far rather hear about a false alarm than learn a week later about a complication that could have been treated on the day it began.

Frequently asked questions

Is a mastoidectomy major surgery?

Yes in significance, moderate in disruption. It is performed under general anesthesia and involves drilling bone within millimeters of the facial nerve, inner ear and brain lining, which is why it demands specialist skill. The incision itself is small and hidden behind the ear, blood loss is usually minor, and the NHS notes people having cholesteatoma surgery often go home the same day or after one night.

How long is recovery from mastoidectomy?

Most of the visible recovery takes a few weeks, with the full result clear over months. NHS guidance describes about a week off work, keeping the ear dry throughout, and avoiding swimming and flying until the surgeon clears it, often a few weeks. Packing in the ear canal dissolves or is removed at a clinic visit, and hearing typically improves at that point. Scars, taste changes and hearing settle over the following months.

What is life like after mastoidectomy surgery?

For most people, quieter and drier. The chronic discharge stops, which changes daily habits more than people expect. Hearing varies with how much damage existed beforehand. After a canal wall up operation, the ear looks normal and needs mainly follow-up. After a canal wall down operation, you have a mastoid bowl that needs periodic suction cleaning in clinic and lifelong care to keep water out.

How serious is mastoiditis?

Serious enough to be treated in hospital, because the mastoid shares thin walls with the brain lining, a major vein, the facial nerve and the inner ear. MedlinePlus lists meningitis, brain abscess, facial paralysis and hearing loss among possible complications. Most cases are controlled with intravenous antibiotics, sometimes with drainage of the middle ear; surgery is reserved for infections that do not settle or that form an abscess.

Does a mastoidectomy affect hearing?

It can, in either direction. Removing disease that was bridging eroded hearing bones can leave hearing temporarily worse until reconstruction heals, while repairing a perforated eardrum can improve it. A permanent inner ear loss is uncommon but is listed by the NHS as a possible complication. Your surgeon should describe a realistic range for your ear based on your hearing test and scan, not a promised figure.

Can cholesteatoma come back after mastoidectomy?

Yes. The NHS notes cholesteatoma can return, sometimes years later, so long-term follow-up is standard. After a canal wall up operation, where preserved bone can hide small remnants, a check operation or an MRI within about a year is often planned. After a canal wall down operation, recurrence is usually visible during routine clinic cleaning. Attending follow-up even when the ear feels fine is the main safeguard.

What does canal wall down mastoidectomy mean?

It means the surgeon removes the bony wall between the ear canal and the mastoid, creating one open cavity, often called a mastoid bowl, and then rebuilds the eardrum. The advantage is that any returning disease is easy to see and clean in clinic. The trade-off is a cavity that collects debris, needs periodic suction cleaning, and is prone to infection if water gets in, so precautions become lifelong.

Will I have a visible scar after mastoidectomy?

Usually not a noticeable one. The incision is typically placed in the natural crease behind the ear, where hair and the ear itself conceal it, and it fades over months. Some surgeons perform parts of the operation through the ear canal with an endoscope, reducing the external cut further. Numbness of the outer ear around the incision is common early on and generally improves with time.

Can children have a mastoidectomy?

Yes. Mastoiditis is more common in children than adults, according to MedlinePlus, and cholesteatoma also occurs in childhood. In children the pathway is similar: imaging, general anesthesia, and a hospital stay of a day or so, with parents encouraged to stay. Preparation focuses on explaining the bandage, the blocked-ear feeling and the need to keep the ear dry. Any pain relief or drops are prescribed and adjusted by the pediatric team.

When can I fly or swim after mastoidectomy?

Only when your surgeon confirms the ear has healed enough, which NHS guidance describes as often a few weeks after surgery rather than a fixed date. Pressure changes during flight and water entering a healing ear both risk disrupting the repair or causing infection. If you have a canal wall down cavity, keeping water out of the ear typically becomes a permanent habit, often with fitted swimming plugs.

References

• MedlinePlus Medical Encyclopedia: Mastoiditis
• MedlinePlus Medical Encyclopedia: Cholesteatoma
• NHS: Cholesteatoma

This article is for general information only and is not a substitute for professional medical advice. Please consult a qualified doctor about your individual situation.