Ear drum perforation
What causes the ear drum to perforate?
Most perforations of the ear drum are caused by either trauma, infection or as a result of ear surgery. There are different types of trauma that can cause the ear drum to perforate:
Direct trauma – such as from cotton bud or Q-tip used to clean wax from the ear canal, or from head trauma such as during a road traffic accident.
Acoustic trauma – due to exposure to very loud noise at close range such as from a bomb blast, a loud speaker or an open slap to the ear.
Barotrauma – due to sudden changes in pressure, especially during scuba diving or sky-diving.
Middle ear infections can also cause the ear drum to perforate. Most of these heal spontaneously but some can persist and cause chronic problems such as ear drainage and hearing loss (known as chronic otitis media).
The most common surgical cause of an ear drum perforation is ventilation tube (grommet or T-tube) insertion. Read more about this complication of ventilation tubes here.
What kind of problems can a perforated ear drum cause?
Many ear drum perforations will heal spontaneously without further problems. Traumatic perforations and those caused as a result of a middle ear infection typically heal within 2 to 4 weeks. Of those that do not heal, recurrent ear infections, hearing loss and cholesteatoma can be a problem.
These can occur because the ear drum acts as a natural barrier that prevents bacteria and fungi in the outer ear (where they are common) from entering the middle ear. With this natural barrier gone, bugs in the water can wash through the perforation and cause infections during swimming or showering/bathing. The middle ear provides a suitable environment for these bugs to proliferate and hence cause infection. People who have an ear drum perforation and also wear hearing aids are also more prone to developing ear infections due to the increased humidity that hearing aids cause in the ear, which encourages bacteria and fungi to multiply.
Hearing loss is generally only a problem if the perforation is very large, involving most of the ear drum, or if the hearing bones (ossicles) have been exposed for a long time or have been exposed to many ear infections and have developed scar tissue or calcification (tympanosclerosis) around them or partially eroded.
Dead skin from the ear canal can sometimes abnormally migrate from the ear canal, through the hole and into the middle ear where it can form a cholesteatoma (a type of skin cyst), which can itself cause infections and hearing loss in addition to other potentially serious problems. It is thought that perforations near the edge of the ear drum (marginal perforations) may be more prone to developing this. Read more about cholesteatoma here.
How is it diagnosed?
People who present to their doctor or ENT specialist with a perforated ear drum are usually experiencing one of the problems mentioned above. Sometimes a perforation is picked up on a routine examination by the GP without the person knowing that they had one. It is usually diagnosed based on the symptoms that the patient is having and on examination of the ear drum with an otoscope. In most cases the ENT surgeon will also ask for a hearing test to be performed to ensure that there is no associated hearing loss.
How are ear drum perforations treated?
In cases where the perforation is dry, not located at the edge of the ear drum, shows no evidence of cholesteatoma formation and is not associated with recurrent infections or a hearing loss, nothing needs to be done unless the patient prefers it.
Some people will prefer not to have surgery to repair their ear drum even if problematic. If hearing loss alone is an issue, then a hearing aid can be tried, but this can itself cause infections when used in an ear with a perforation for reasons described above. Taking hearing aid breaks can reduce the infection risk by allowing the aided ear to dry out for a few hours throughout the day. In cases of recurrent ear infections caused by getting the ear wet, simple precautions can be taken to prevent them by keeping the ear dry during swimming and showering/bathing and using antibiotic ear drops during infections.
For a problematic perforation, a repair of the ear drum, called a cartilage tympanoplasty, can be performed in which a piece of cartilage is taken from around the ear and used to patch the hole. This will definitively stop recurrent infections by making the ear waterproof once again and remove the need for ear protection during swimming or showering/bathing. Tympanoplasty can also potentially improve hearing loss, especially in large perforations. Sometimes the hearing loss is due to a concurrent problem with the ossicles, in which case they can be assessed and potentially repaired at the time of tympanoplasty (called an ossiculoplasty).
For marginal perforations a tympanoplasty is recommended to reduce the risk of cholesteatoma.
Are antibiotic ear drops safe to use in an ear with a perforation?
Yes. Many non-ENT doctors do not feel comfortable about prescribing ear drops into an ear with a perforation because of a theoretical risk of certain types of drops causing irreversible deafness. Such drops (such as Sofradex and Gentamicin) contain antibiotics that belong to the aminoglycoside family, which do have a risk of hearing loss when administered intravenously, but the risk is very small in drop form. The ENT-UK group, which provides guidance for ENT surgeons, has published guidelines that state that drops containing aminoglycosides can be safely used in ears with perforations for up to two weeks without issue. For this reason most ENT surgeons will routinely prescribe these drops for an ear infection, even in the presence of an ear drum perforation. A baseline hearing test is recommended before drops are started where possible.
There are other drops that do not contain aminoglycosides, such as Ciproxin and Ofloxacin, but instead contain antibiotics that belong to the quinolone family. These can be used as a safe alternative to the aminoglycoside-containing drops.
Read more about tympanoplasty here.
Read more about ocssiculoplasty here.
Read more about how to efficiently keep the ear dry during showering and bathing here.
Download a leaflet on the proper way to instil ear drops into the ear here.
Here is shown a dry, relatively small perforation of the right er drum caused by a grommet. This sized perforation is unlikely to cause hearing loss.
A large (sub-total) peforation involving most of the ear drum. This size of perforation may be associated with a hearing loss. As it is close to the edge of the ear drum, dead skin from the ear canal can migrate inwards through it and form a cholesteatoma.
Another large (sub-total) peforation involving most of the ear drum. In this case, dead skin from the ear canal has migrated inwards through it at the top of the hole and formed a cholesteatoma. In this patient it is causing infections. Pus can be seen at the bottom right of the picture. This patient will have a large hearing loss.