Grommet Surgery Melbourne
Grommet surgery is a procedure that places a ventilation tube in the ear drum. This tube (or grommet) drains fluid out of the middle ear and allows ‘equalisation’ of air pressure between the outside environment and the middle ear. Grommet surgery is a minor procedure, commonly performed in children, for recurrent ear infections or persisting middle ear fluid.
When is grommet surgery recommended?
Grommet surgery, as mentioned above, is one of the most common day-case paediatric surgeries performed. Indications for surgery include:
Recurrent ear infections
Fluid in the middle ear that is persisting.
Chronic infection that doesn’t resolve with antibiotic therapy
Severe ear drum retraction
Severe eustachian tube dysfunction
The ear infections ( episodes of ‘acute otitis media’) have to be recurrent enough to warrant surgery. The duration and severity of each infection is also considered. Fluid in the middle ear can be described as a “middle ear effusion” or “glue ear”. When treating a persisting middle ear effusion - the duration and effect that it is having on the patient is weighed up in deciding whether to perform the surgery. The reason that the fluid is described as a ‘glue ear’ relates to the consistency of the fluid in the middle ear. The fluid (or effusion) often has a very thick, tenacious consistency - that is almost ‘glue’ like. Hence the term ‘glue ear’. Severe eustachian tube dysfunction can cause pain particularly when outside pressure changes - such as when flying or diving. (Think of a water bottle squashing inwards due to pressure change on an aeroplane). If the eustachian tube dysfunction is causing significant pain during these activities and medical treatment is not effective, grommet insertion can also be helpful.
What are Grommets?
A grommet is a small tube with a flange or ‘lip’ that allows the tube to sit in the ear drum. The tube has an opening that allows fluid and air to leave the middle ear space. The tube is tiny - with the hole (or lumen) of the tube being less than 1.27mm wide.
Other names for grommets include:
pneumatic equalising or PE tubes.
Australia and UK patients most commonly refer to ventilation tubes simply as grommets (derived from industrial term to mean a washer or eyelet with a hole in the middle).
Why does the fluid not clear naturally?
The ear is divided into three chambers. The outer, middle and inner ear. The outer ear or ‘external auditory canal’ is about 2.5cm long and is a part bone and part cartilaginous canal. The tympanic membrane or ear drum separates the outer ear from the middle ear. The ear drum is usually fixed between the outer and middle ear compartments. The middle ear houses the hearing bones or ossicles. These are the malleus, incus and stapes (or the hammer, anvil and stirrup). These three bones are connected and form a bridge between the ear drum and inner ear. The malleus is connected to the tympanic membrane and the stapes is connected to the inner ear via a small opening into the inner ear called the oval window. In broad terms, the sound causes the ear drum to move which in turn moves the ossicular chain and this then allows for movement of fluid in the inner ear which stimulates the hearing nerve (or cochlea) allowing for sound perception to be carried along the cochlear nerve to the central brain.
There is a natural connection between the middle ear compartment and back of the nose called the eustachian tube. This tube, like the outer ear, is a part bone and part cartilaginous tube. It is much smaller and more complex than the external ear canal. When the eustachian tube is working it allows for air and fluid to leave the middle ear. Yawning, chewing or blowing the nose can open the eustachian tube in healthy individuals. In young children, the eustachian is still developing and this can predispose to infections in the middle ear or allows fluid accumulation in the middle ear space. Even adults can experience this with a cold or upper respiratory infection - the eustachian tube becomes swollen and the middle ear does not ‘equalise’ well. This can cause decreased hearing and result in a blocked sensation. If fluid accumulates in the ear this hearing change can be more pronounced. In medical terms, this results in a ‘conductive hearing loss’ akin to hearing underwater.
What does Grommet surgery involve?
Grommet surgery is a short procedure. It is usually performed in a hospital setting under a general anaesthetic. Usually, a breathing tube (endotracheal tube) is not required - rather a breathing mask (Laryngeal Mask Airway) is placed into the throat and sits above the voice box.
The operating microscope is used to examine the external ear canal and ear drum. Any wax or debris is cleared. A small incision (or myringotomy) is made into the ear drum and fluid is then suctioned from this created hole. A grommet or ventilation tube is then selected based on the indication for the surgery. Common options include a Shepard tube, Collar buttons or Reuter Bobbin ventilation tube. Less commonly, a long term grommet is required and this is called a “T-tube.” The grommet is placed into the myringotomy site. Antibiotic drops are sometimes then applied into the ear. The procedure usually takes 10-20 minutes. The anaesthetic is stopped and the patient is taken to recovery and woken up. Patients are discharged home several hours later.
What is the post-operative care following Grommet surgery?
Grommet surgery is not a particularly painful procedure. Panadol can be given, as needed, in the days after the surgery and is usually all that is required. There can be mild irritation of the ear canal and discharge. Prescription antibiotics ear drops may be prescribed. It is important to let any treating doctors know that there are grommets in place - as not all ear drops are appropriate to use with the grommets ( given that the ears drops could enter the middle ear via the grommet lumen).
Avoiding water exposure after grommet surgery:
This is a debated topic. In Australia, the general advice is to avoid water exposure to the ears after grommet insertion. There is a risk of water entering the middle ear and causing an ear infection. This involves wearing earplugs when bathing or showering. During swimming using earplugs and a swimming cap is also advised. There are a variety of semi-fitted, reusable earplugs.
However, the number of ear infections caused by swimming or water exposure is still low. Especially in young children or those challenged by plugging the ears - it may be acceptable to try without plugging the ears, in the first instance. This should be discussed with your surgeon.
If the ear discharges fluid or pus after the surgery this indicates there is an infection. It can occur in the setting of a cold or upper respiratory infection as well. It should be assessed by your doctor. Topical antibiotic drops usually clear this infection. Your GP or Dr. Gordon should be consulted - sometimes ear suctioning or further treatment is also needed.
A post-operative hearing test is arranged at about 4 weeks after the surgery. This checks that the hearing has normalised and also checks that the grommet is not blocked. If there is any hearing loss or change in speech (for children) in the months after the grommet surgery - a sooner follow up appointment should be arranged.
Following grommet surgery, the ears should be checked every 6 months - this looks at the ‘status of the grommets’. To see if the grommets are still sitting in the ear drum and if the hole (lumen) of the grommet is still open. Usually, the grommet falls out of the ear drum between 6 - 12 months after the surgery. This depends on a number of factors including the type of grommet used. The movement of the grommet into the out ear canal is termed ‘grommet extrusion’ and is a painless (and often unnoticed) phenomenon. The grommet is often found sitting in the external ear canal or falls out of the ear canal together with ear wax.
If the grommet does not extrude after an extended period of time (18- 24 months) consultation with Dr. Gordon is required. Rarely, further surgery is required to remove the grommet, allowing the hole in the ear drum to close. In a small group of patients, the hole made to insert the grommet (myringotomy site) does not close - this hole is monitored and may also require surgery to ‘patch’ the ear drum closed. The medical term for this procedure is ‘myringoplasty.’
Further grommet surgery
About 10 - 15% patients will require a repeat set of grommets. This can be described as a ‘second set’ of grommets. Revision grommet surgery is more common when the initial surgery is performed in younger children and as a sole procedure (without removing the adenoids). Also, some features of the Eustachian tube, soft palate and facial development can make repeat grommet surgery more likely. At a second (or subsequent surgery) the grommet tube may be changed to a longer staying tube. Additionally, there will be a discussion about possibly combining this revision grommet surgery with adenoid removal (adenoidectomy).
This advice is only general in nature, may not be applicable to every patient. Please contact Dr. Dan Gordon’s rooms for further information.