Examining The Ear: Part 1
This is Part 1 of the Examining The Ear series, aimed at giving an insight into the anatomy and conditions of the ear.
Anatomy Of The Ear…
The ear is made up of three different parts. The outer ear, the middle ear and the inner ear. The outer ear is made up of the pinna and the ear canal, and everything before the eardrum. The middle ear is the air filled space behind the eardrum, where the three smallest bones in the body, the ossciles, are suspended. These bones are called the malleus, the incus, and the stapes. There is also a tube connecting the middle ear space to the throat called the Eustachian tube. The inner ear is fluid filled and contains the cochlea, which transfers the vibrations of the sound waves that pass through the outer and middle parts into an electrical stimulus that is sent along the auditory nerve and is interpreted by the brain as sound.
The tools your audiologist uses to look into your ear are vast and ever-evolving. As time goes on, technology develops and we discover new and better ways of examining the ear. The most important tools that audiologists use to examine the ear are listed below:
Welch Allyn Diagnostic Otoscope
Contains a rechargeable battery supply with a small bulb in the head for illumination. The speculum allows access to the external ear canal. The rear lens provides low power magnification of the visualised structures.
An endoscope is used to look inside the body for medical reasons; the oto-endoscope is specifically used for for endoscopy of the ear. It is connected to a fibreoptic light source for illumination, and the findings are recorded and shown on camera. A recent development in oto-endoscopy is the iCLEARscope video oto-endoscope. For more information about this tool that Hearing Healthcare Centre have recently began using (pictured right), click here.
When examining the ear with the tools listed above, your audiologist will look out for key signs to tell if the ear is healthy or not.
Firstly, your audiologist will look for any obvious abnormalities, such as inflammation or sores, on the outer ear and mastoid. They will then begin to look inside the ear into the external canal using an otoscope. During this, they will look for any signs of ear wax, foreign bodies, skin changes, and discharge.
After this, they will look further into the middle ear at the tympanic membrane, otherwise known as the eardrum. There are four main landmarks the audiologist will look out for when examining the tympanic membrane:
- Lateral process of malleus
- Cone of light
- Pars tensa
- Pars flaccida
These areas are labelled on the diagram below, along with other key parts of a healthy eardrum…
Right tympanic membrane