ABOUT THE CONDITION
How does the ear work?
The ear consists of the outer, middle and inner ear. Sound travels through the outer ear and reaches the eardrum, causing it to vibrate. The vibration is then transmitted through three tiny bones in the middle ear called ossicles. The vibration then enters the inner ear and the nerve cells within the inner ear are stimulated to produce nerve signals. These nerve signals are carried to the brain, where they are interpreted as sound. The middle ear also contains other structures like your balance system and facial nerve. It also sits very near to the brain which lies just above it.
Figure showing the outer, middle and inner ear and ossicles (*)
What is the mastoid bone?
The mastoid bone is the prominent bony area that can be felt just behind the ear. It contains a number of air spaces. It connects with the air space in the middle ear. Therefore ear diseases in the middle ear can extend into mastoid bone.
Why do you need mastoid surgery?
The commonest reason for mastoid surgery is for a condition called cholesteatoma. This is a collection of dead skin cells that grows like a sac from the ear drum into the middle ear and mastoid bone. Sometimes mastoid surgery is performed for access as part of other operations for example cochlear implant surgery.
A: Cholesteatoma in the top (Attic) of ear drum; B: Cholesteatoma in the back of ear drum;
What problems can develop from cholesteatoma?
Over a few years, as this sac of skin grows larger it can cause repeated ear infections. The enlarging sac can also start to rub and erode the surrounding structures in and around the middle ear such as the small bones conducting sound, bony covering of the inner ear, bone protecting the nerve which moves the face and bone between the ear and the brain.
What symptoms may I develop?
Repeated ear infections can cause a smelly discharge from your ear and cause ear discomfort. Erosion of the bones of hearing can cause a hearing loss. You can also experience disturbances in your balance and develop tinnitus which is a sound in your ear e.g. buzzing, hissing, and ringing. Very rarely the infection can cause complications such as meningitis and abscess formation. This infection can produce fever, severe pain and swelling around the ear and stiffness of neck.
Will I need any tests?
In the first instance your consultant will examine your ear with a handheld otoscope. A microscope may be used to examine the ear more thoroughly and this can be accompanied by suctioning earwax for a better view. Suctioning of your ear is very safe but can sometimes cause mild discomfort and dizziness. An audiogram will be performed to check your hearing levels. A CT scan or MRI scan may be requested by your consultant.
What treatment may I need?
Ear suction and antibiotic treatment will only provide temporary relief from your symptoms. The only safe and effective way of treating cholesteatoma is to have it removed with an operation
ABOUT THE PROCEDURE
What is the benefit of having surgery?
Mastoid surgery is also commonly called mastoidectomy. There are various forms of the operation often tailored to the size of the cholesteatoma. Other terms include atticotomy, atticoantrostomy and combined approach tympanoplasty.
The operation almost always is performed under a general anaesthetic. It can take between 1 hour to 3 hours.
Surgery involves making a cut above the opening of your ear or behind your ear. Cuts will also be made in your ear canal. Some surgeons might do the operation through the ear canal with the help of a telescope called endoscope especially if the disease is limited. Sometimes the mastoid bone is opened up with a drill to get to the disease. Sometimes other combined techniques with an endoscope and LASER are used in mastoid surgery.
Once the bone covering the infection within the mastoid cells is removed, the resultant bony defect is called a mastoid cavity. Some surgeons leave the mastoid cavity open into the ear canal. This allows the surgeons to inspect the mastoid cavity easily. Others close up the mastoid cavity with bone, cartilage or muscle from around the ear. Sometimes the opening of the ear is made bigger to aid examination and cleaning in the outpatient clinic. You should discuss with your surgeon his/her preferred approach. At the end of the operation, packing will be placed in your ear while it heals. The packing can be left for up to 3 weeks before removal at a clinic. Some surgeons use absorbable packing which does not need to be removed. Any stitches can be removed at your GP Surgery after 7 to 10 days. There may be also a head bandage for up to 24 hours.
Picture of a mastoid cavity with larger ear canal and ear drum
What are the alternatives to surgery?
Sometimes surgery is not the best option for you. This is a decision you will make together with your surgeon. Cleaning your ear regularly with suction at a clinic and using antibiotic drops intermittently may contain the disease but will never cure it completely. There will continue to be a risk of developing a complication from an enlarging cholesteatoma. These rare complications are, meningitis/brain abscess, facial weakness, dizziness and total loss of hearing.
Other Factors to consider.
If your job involves swimming or requiring an intact eardrum, (eg jobs in the military) or depends on a normal taste sensation (chef), mastoid surgery can cause problems and you must discuss this with the surgeon before the operation.
ABOUT THE RISKS
Complications fall into one of the following categories:
What are the risks?
It is very common to experience taste disturbance following surgery. This is because the taste nerve runs very close to the ear drum and may sometimes be injured during surgery. This abnormal taste occurs on the same side of the tongue as the operated ear. This is usually temporary but can sometimes be permanent.
There is a rare complication of facial weakness following surgery. The risk is higher with revision operations. The facial nerve which is the nerve that controls movement of the face runs through the mastoid bone and middle ear. Sometimes the nerve swells after surgery but this is temporary and facial movement recovers. If the nerve is damaged, there may be permanent weakness to the face.
Allergic reaction to the medication in the ear dressings: Some patients may develop a skin reaction to the ear dressings. If your ear becomes itchy or swollen, you should seek advice from your surgeon. The ear dressings contain medication to prevent infection.
Recurrence/ Residual disease
Recurrence and residual disease is common to very common. The risk is higher with more extensive cholesteatoma and may be related to the surgical technique used by your surgeon
What should I expect after the operation?
Loss of hearing
Most patients will have a degree of hearing loss before the operation. It is uncommon to lose your hearing completely after the operation. If the disease has eroded your inner ear or your balance system there is a higher risk of total and permanent hearing loss.
This is normally temporary but can last longer if the disease has damaged the balance organ.
You may already hear a noise in your ear (tinnitus) before surgery but it can sometimes be worse after. You may continue to experience tinnitus especially if you have hearing loss.
A mastoid cavity is still commonly created and and may require care in the form of regular cleaning to avoid excessive accumulation of wax. Infections can occur causing ear discharge and this can sometimes be a chronic problem.
After the operation, you will be transferred to the recovery area. When your anaesthetic has worn off, you will be taken back to the ENT ward. You will notice that you have a dressing over your ear and sometimes a head bandage as well.
What else will I expect after surgery?
Your ear will be sore after the operation and you will be given painkillers by the hospital and some to take home. This discomfort often lasts for up to 2 weeks. You will have packing in your ear and this is left in the ear for up to 3 weeks. Your ear will feel blocked due to the packing. You can expect a bit of spotting from blood arising from your packing or your wound. You can apply some cotton wool and dressing to these areas until the spotting stops. The cotton wool and dressing should be changed regularly. If you have stitches, this can be removed by your GP practice nurse after 7 to 14 days. If your packing starts to fall out, you can trim the loose end with a pair of clean scissors and leave the rest in place. You should keep your ear dry during this period.
If you have any concerns with your ear please get in touch with your ENT department.
How long will I stay in hospital?
You can sometimes get home the same day but be prepared for an overnight stay.
If there is a complication following surgery, you might need to stay in hospital for longer.
What is the recovery period?
How quickly you recover depends on the extent of your operation. You may be able to go back to work after 2 weeks, but will have to keep water off the ear. Most people will fully recover after 6 to 8 week.
A post-operative outpatient appointment will be made a few weeks after surgery. If there is packing in your ear, it will be removed at this visit. Following mastoid surgery, it is not uncommon to require long term care of the ear, especially if you have a mastoid cavity.
Before you give your consent to the treatment, you should ensure that you understand the benefits that you will gain from the procedure, the risks (in particular the ones that may matter most to you) and go through any questions you may have with your specialist.
Author: Mr Arun Iyer
Disclaimer: This publication is designed for the information of patients. Whilst every effort has been made to ensure accuracy, the information contained may not be comprehensive and patients should not act upon it without seeking professional advice.