Question 1

What is a CAT?

Accepted Answer

The aim of the surgery is to remove the cholesteatoma (undefined)and prevent any further damage being caused to your ear and surrounding structures. A secondary aim may be to improve hearing, depending on the type of damage that has been caused.

Question 2

What does a CAT involve?

Accepted Answer

Needle and sticker electrodes are placed on the face and head to provide the surgeon with invaluable information on the position of the important nerves. 
A small amount of hair needs to be shaved around the ear to reduce the risk of skin infection.
Surgery is performed via a 4-6cm incision behind the ear.
The first part of the operation involves removing all of the cholesteatoma. The mastoid bone (the hard bone behind your ear) is carefully drilled away to expose the cholesteatoma, which is removed under microscopic vision.
Through the ear hole the cholesteatoma is exposed from the front, and a microscope is used to magnify and help visualisation. If the cholesteatoma has grown to become stuck to vitals structures (e.g. nerve of facial movement, the inner ear, balance organ, and brain lining), it is carefully dissected to be free of them. All the cholesteatoma is removed. The bones of hearing are removed if there is any chance of further hidden cholesteatoma being left behind. 
The second part of the procedure involves repairing any damage that the cholesteatoma may have already done, by placing cartilage where bone has been eroded. If the bones of hearing are removed along with the disease an ossiculoplasty (javascript:void(0))is performed to restore the hearing using an artificial prosthesis. In most cases this is done during the same surgery. Although in some cases, the surgeon may elect to come back to finalise this when they are satisfied that there is no remaining cholesteatoma.

Question 3

How successful is a CAT?

Accepted Answer

More than 90% of patients report a resolution to ear discharge following surgery. Nearly all patients with pre-existing hearing complaints report an improvement when an ossiculoplasty is undertaken with this procedure.
One in five will have cholesteatoma recurring and require further operations.

Question 4

What are the risks of a CAT?

Accepted Answer

It is a safe procedure done frequently in specialist hospitals without any serious problems. However, there are potential risks of surgery that you should be aware of: 
All surgical procedures have risks of infection, bleeding and scar. Infection risk is reduced by operative techniques, a shot of antibiotics and an antimicrobial pack that is placed in your ear after the operation for 2 weeks.
Severe bleeding is uncommon after ear surgery. However, to reduce the risk of bleeding under the skin post-operatively, we place a pressure bandage around your head after the operation that stays on for up to 24 hours, which you can remove yourself the next day.
Scarring is reduced by meticulous closure using automatically absorbing stitches for any incision we make.
Reduction in hearing: if the Cholesteatoma is wrapped around your bones of hearing we will have to sacrifice those bones to reduce the risk of recurrence. Whilst we reconstruct the hearing with prosthesis, a minority of patients will notice a reduction in their hearing. More frequently, patients report an improvement in their hearing. There is a tiny risk of total hearing loss in the operated ear. 
1 in 5 people complain of a metallic taste on the tip of half their tongue following surgery. This is temporary. Permanent change in taste is very rare. If your taste is central to your career (e.g. chef or sommelier) please discuss this with your surgeon.
The effect of this surgery on tinnitus is unpredictable. Many patients report an improvement in their pre-existing tinnitus, some report no change and rarely patients report deterioration in their tinnitus. 
Patients occasionally report temporary balance disturbance following surgery. Permanent change in balance is extremely rare following this surgery. 
There is a small but serious risk to the nerve that controls face movements on that one side of the face. We use a nerve monitor during surgery to prevent this, in addition to pre-operative imaging which alerts us to the anatomy of this nerve. In the few cases where this injury have been reported, the majority are temporary. Permanent damage would require further surgery to restore some function to the muscles of the face. 
There is a small but serious risk of leakage of brain fluid and meningitis. This is most pertinent in those whose Cholesteatoma has already damaged the lining between the brain and the ear. If leakage of brain fluid is noted during the operation we will fix it, by using cartilage and other grafts harvested from around the ear. However, if it is noted following surgery, you will need to have a second operation to fix this. 
This operation is done under a general anaesthetic and the anaesthetist will discuss the risks of an anaesthetic with you on the day.

Question 5

What to expect on the day of your CAT?

Accepted Answer

Combined approach tympanomastoidectomy is a major operation done in an operating theatre. It is done under a general anaesthetic as a day case (patients go home on the same day).
You/your child will be expected to avoid food and liquids in the hours before you arrive (you/your child can eat up to 6 hours and drink water 2 hours before your arrival to hospital). You/your child will be checked into a ward and introduced to the nursing team. Your anaesthetist and surgeon will meet you before surgery: you will have a chance to ask any final questions at this stage. (Although it is recommended that questions are addressed before your surgery date).
For children, a parent will be allowed to bring their child to the theatre area, where anaesthesia is started. As the child falls asleep the parent will be escorted back to the ward.
The procedure takes 3-4 hours, and you/your child can go home 4-6 hours after surgery if you are eating, drinking, have emptied your bladder, and have someone to go home with you.
After the procedure is finished, tight bandage is placed around your/your child's head and ear to reduce the chance of bleeding following surgery. You can take this off yourself the following morning.

Question 6

What to expect after your CAT?

Accepted Answer

A pack is left in the operated ear for around 2 weeks, to reduce the risk of post-operative infections. Due to the pack, patients often cannot hear effectively from this ear until we remove it in clinic. People who have surgery must keep their ears dry and avoid rapid air pressure changes (e.g. flying, diving) for the first 2-4 weeks. People who have surgery traditionally take 1-2 weeks off from work/school depending on the physicality of their daily routines.

Mr Nish Mehta

Consultant Otologist, Ear, Nose and Throat (ENT) &

Auditory Implant surgeon

MBBS, PhD, FRCS (ORL-HNS)

E: office@nishmehta.co.uk

T: 020 31503115

Combined Approach Tympanomastoidectomy (CAT)