FAQs

Yes. The main aim of cholesteatoma surgery is to completely remove the cholesteatoma. This is difficult due to complex anatomy of the area in which cholesteatoma arises as well as the variable nature of the cholesteatoma. Surgery using dissection alone results in cholesteatoma being left behind in 20-30% of cases, even in experienced hands. The laser greatly reduces the risk of leaving cholesteatoma because it is minimises bleeding during surgery, can be aimed around the obstacles that exist in the ear, is precise and simple to use, being 'point and shoot', and can vaporise cholesteatoma that is firmly stuck and difficult to dissect.

The laser assists the removal of cholesteatoma in the following situations:

When the cholesteatoma is bloody and inflamed, dissection can cause bleeding that renders continued surgery difficult or even unsafe. The laser uses heat to vaporise the cholesteatoma and so can cauterise the bleeding as it clears away the cholesteatoma.

If the cholesteatoma is strongly stuck to underlying tissues, dissection can cause the tissue to fragment and this can result in tiny fragments being overlooked. Since the laser works in a completely different way, not by dissection but by vaporising the cholesteatoma, the laser can just as easily remove adherent cholesteatoma as cholesteatoma that can be freely dissected.

When the cholesteatoma is difficult to reach with a conventional instrument, such as the spaces around the hearing bones, the laser helps because it is 'point and shoot' and so is easier to use than dissecting instruments.

If the cholesteatoma is hidden from direct view, the laser is fibre guided and the fibre can be bent around the obstacle. The laser can also be bounced off a mirror. The hidden cholesteatoma can be viewed in the mirror at the same time. Because the laser does not cause bleeding it is easier to use around an obstacle than dissecting instruments.

After all the cholesteatoma appears to have been removed, we know from worldwide results that there is a reasonable chance that there will be tiny fragments of residual cholesteatoma. It is easy with the laser to heat the entire cholesteatoma bed to denature and eliminate possible remnants. It is not possible to do this so completely with any other instrument.

Only in areas where the cholesteatoma is easy to access, where is it not inflamed, bloody, attached to hearing bones, adherent or hidden behind obstacles, may it be preferable to use conventional dissection instruments. In these circumstances, mainly in the mastoid air cells, the precision of the laser may be a disadvantage because conventional dissection can remove the disease more quickly.

All surgical instruments used on the facial nerve have the potential to injure the nerve if used carelessly. The blame for any facial nerve injury lies on the surgeon not the instrument.
Specialist ear surgeons are trained to identify and protect the facial nerve as part of cholesteatoma surgery. A specialist ear surgeon will identify the facial nerve prior to removing the disease, so that the nerve can be protected throughout the process of clearing away the cholesteatoma.
All specialist ear surgeons will already be trained to use other potentially hazardous instruments, such as the surgical drill, with care near the facial nerve. In the same manner, the laser should not be used before the facial nerve has been identified.
On occasion, cholesteatoma erodes the bone over, and becomes firmly adherent to, the facial nerve itself. The laser is not used under such circumstances and the cholesteatoma is dissected from the nerve.

Mr Hamilton published a prospective comparison of dissection and laser surgery for cholesteatoma in the world's leading ear surgery journal in 2005. Even though he was meticulous when dissecting out the disease, residual cholesteatoma subsequently was found in 30% of cases. When he used the laser as well, subsequently there was residual cholesteatoma in only 3%. After this, Mr Hamilton has only ever operated on cholesteatoma when a laser was available.

A different journal included an editorial to commend the high quality of the research in Mr Hamilton's paper and to recommend that all cholesteatoma surgery should be undertaken with a laser.

The laser has a range of properties that match the problems set by cholesteatoma.

The properties of the laser which make it well suited to cholesteatoma surgery are that it is easy to use, being 'point and shoot' technology; that it is haemostatic; that it can be transmitted or reflected around corners; and, because it does not involve movement, it is safe to use around or on hearing bones.

The section "How does your operation differ from cholesteatoma surgery that relies on dissection?" on this website provides further details on how these properties match up with the problems set by cholesteatoma.

It is usually not possible to predict accurately the answer to this question for a specific ear before the operation is performed. This is because there are many factors that can influence the hearing in an ear affected by cholesteatoma. The following detailed information explains how the laser can provide better hearing than standard dissection techniques:

Loss of hearing in the affected ear is due to a combination of two types of hearing loss: damage to the cochlea and the loss due to disease or damage to the middle ear.

Damage to the cochlea

Pre-existing cochlear hearing loss is mainly due to 'wear and tear'. This increases with age.

Cochlear hearing loss due to ear surgery is more commonly caused by excessive movement of the hearing bones during surgery, as this can transmit damaging energy into the cochlea. This is similar to how loud sound can damage hearing. Standard dissection relies on movement to get rid of cholesteatoma and so is risky around or on the hearing bones. If relying on dissection to remove cholesteatoma, hearing bones involved in cholesteatoma are removed with the disease to avoid permanent damage to the cochlea. The laser can remove disease from the ossicles without movement and without putting the cochlea at risk.

Cochlear hearing may be worse after surgery if the inner ear organs have been involved. This is rare but is much more likely if the cholesteatoma has eroded into the inner ear (a "fistula"). Under these circumstances, conventional dissection removes the cholesteatoma from the fistula. This carries a risk of opening the inner ear, which may cause cochlear hearing loss. The laser can kill the cholesteatoma cells eroding the inner ear without opening the inner ear. Mr Hamilton has published research showing how a laser technique for this purpose is better at preserving inner ear hearing than conventional surgery.

Damage to the middle ear hearing apparatus

Pre-existing middle ear loss in a cholesteatoma patient may be due to erosion of the hearing bones by the cholesteatoma, inflammatory fluid within the middle ear or loss of middle ear volume due to inflammation and the cholesteatoma, itself. Ear discharge in the ear canal can also prevent sound from reaching the ear drum.

After surgery, hearing loss in the middle ear may be affected by the integrity of the hearing bones, the geometry of the residual hearing bones, the stiffness of the ligaments of the hearing bones, the size of the middle ear space, the inflammation of the lining of the middle ear space, the ventilation of the middle ear and the integrity of the ear drum, even before considering the shape, position, material and length of any hearing prosthesis.

Approximately one quarter to one third of patients with cholesteatoma have intact hearing bones. With dissection only techniques, removal of cholesteatoma from the hearing bones has a higher chance of damaging the cochlea than laser surgery. Surgeons who do not use the laser generally take out hearing bones affected by cholesteatoma rather than put the cochlea at risk. Many specialist ear surgeons attempt to reconstruct the hearing with prostheses. Non-specialist ear surgeons may not reconstruct the hearing apparatus, with obvious consequences for hearing in many cases.

Mr Hamilton published a paper in the world's leading ear surgery journal providing evidence that preservation of the intact chain of hearing bones provided better hearing than when the chain was dismantled and later reconstructed. This is because the average hearing of the reconstructions was worse and a proportion of reconstructions fall apart.

Cholesteatoma is located within the middle ear space, which is contained within the bones of the base of the skull.
There are two main ways to gain access to the cholesteatoma within the bone. The first ( the 'lateral approach' ) is down the ear canal. The second ( the 'orthogonal approach' ) is through the air filled spaces of the bone behind the ear ( the 'mastoid' ), which is part of the base of the skull.
Down the ear canal, access is limited to the space deep to the ear drum (the 'mesotympanum'), even with an endoscope. However, if the hearing bones are removed, the surgeon can also gain access to space directly above the mesotympanum, the 'epitympanum' or 'attic'.
The orthogonal approach through the air spaces within the skull provides access to the mastoid air cells, the epitympanum and the upper mesotympanum. The deep surface of the hearing bones, hidden from the lateral approach, can also be seen.
The orthogonal approach necessitates a scar behind the ear to allow access to the mastoid process.
If the surgeon chooses to use a purely lateral approach, access is limited to the space deep to the ear drum (the "mesotympanum"), even with an endoscope, unless the hearing bones or ear canal are removed. These extra steps may also be associated with poorer hearing (if the hearing bones are dismantled) and with a higher rate of recurrent cholesteatoma (if the ear canal is partially removed and not reconstructed well). If these are avoided, it can provide access only to limited disease. Despite these clear disadvantages, this form of surgery has undergone a revival recently as it has been undertaken with endoscopes, with the short-term aim of avoiding a scar behind the ear.

The preceding section provides details about the options that the surgeon has to gain access to the cholesteatoma. The skin has to be cut to get into the bone. All surgical procedures on the ear involve a skin, but procedures down the ear canal can hide the scar from everyday view.

With an endoscope, the incision is near the ear drum and won't be seen. This may be useful for uncomplicated ear drum perforation repair, or cholesteatoma limited to the mesotympanum, or the epitympanum if the hearing bones are absent. There is a second ear canal incision, at the outside edge of the ear canal (an 'endomeatal' incision) that allows the use of two hands. It is not visible after surgery and Mr Hamilton tends to use this for disease limited to the mesotympanum. If the cholesteatoma is not so limited, Mr Hamilton prefers to use a combined lateral and orthogonal approach to gain maximal access to the cholesteatoma, to free both hands and to use the laser easily. This needs an incision behind the ear ( a ' postaural' incision ).

Some patients are aware of temporary numbness adjacent to the scar, but most patients experience no pain from the scar, because it is superficial, involves no major muscles and is made with sterile instruments. Because of the excellent blood supply in the head, the scar heals rapidly and almost invisibly. Once healed, they are hidden and cannot be seen in everyday life. When the pros and cons are weighed up together, Mr Hamilton feels that the short-term disadvantages of a nearly invisible scar are less than those of limited access, with increased risks of permanent hearing loss and recurrent cholesteatoma.

The surgical endoscope is a rigid optical rod that the surgeon can insert into the surgical field to provide a different view to that provided by the surgical microsope. The endoscope has a fish eye lens and so can provide a wide field of view. This can provide a view around the curves of the ear canal so that the whole of the ear drum can be seen. Some endoscopes contain a prism so that it they can provide an angled view. This can help inspect adjacent areas that are hidden from direct view by the bone of the ear canal, such as the epitympanum and the back part of the mesotympanum.
Endoscope-only middle ear surgery is promoted by some surgeons because the incision used to gain access to the middle ear can be hidden in the ear canal, so that there are no external stitches.

The endoscope does not remove cholesteatoma, but is simply a way of looking at it. It does not offer any advantages for removing cholesteatoma, as surgeons chiefly use dissecting instruments with the endoscope. Since the endoscope occupies one hand, it limits the surgeon to just one hand to dissect the cholesteatoma, so the disadvantages of dissection are made worse by having only one free hand.
Laser use is hampered by the difficulty of evacuating laser smoke from the ear, with no hand to hold the suction and no space to insert the sucker.
Endoscope-only surgery is limited to the approach through the ear canal.
If the hearing bones are removed, the surgeon can also gain access to space directly above the mesotympanum known as the epitympanum or attic, but at the potential cost of poorer hearing for the patient after surgery.
Because of the limited approach, surgery viewed only with an endoscope may struggle to reach all of the cholesteatoma if the disease extends beyond the mesotympanum and epitympanum. This means that many procedures need to be converted so that the microscope can be used.

Mr Hamilton does use endoscopes for cholesteatoma as accessory instruments for inspecting certain hidden areas of the middle ear, but even in these areas, Mr Hamilton may prefer to use an otological mirror to view these areas if disease is located there, as the laser energy can be bounced off the mirror, something that cannot be done with the endoscope.
The main aim of cholesteatoma surgery is to get rid of all of the cholesteatoma. This requires good access to all of the cholesteatoma and the best techniques to remove what is often a very difficult disease to remove. Sensitive tissues need to be protected and delicate reconstruction may be required.
If successful clearance of cholesteatoma is not achieved, it is due to the anatomy of the ear, the nature of the disease and the difficulties associated with using dissection instruments in this area. The endoscope does not address most of these difficulties and in some ways it compounds them; In a tiny space such as the middle ear and with the delicate structures contained within the space, the relatively crude treatment resulting from one-handed surgery is the opposite of what Mr Hamilton wants to provide.

Yes. In close to 100% cases, not only will the ear be dry, which means that it will no longer discharge, but it will also be robust, which means that it will be able to tolerate water during hair washing, swimming and diving, just like a normal ear.