Tour the Ear

Timothy C. Hain, MD • Page last modified: March 31, 2023

Going from through ear structures from the periphery to the central structures

External, Middle and Inner Ear

External Ear:

Middle Ear

Tympanic Membrane
- TM perforation (a break in tympanic membrane)
- Tympanosclerosis (scarring of tympanic membrane)
Ossicles
- Ossicular chain discontinuity (a break in the bones in the middle ear)
- Otosclerosis (hardening and fusion of bones in middle ear)
Stapes footplate and round window
- Otosclerosis (bony ossification of bones in middle ear)
- Perilymphatic fistulae
Ear Muscles
- Tensor Tympani
- Stapedius
The mastoid sinus
- mastoiditis(infection)
Eustachian tube
- ETD

Inner Ear showing the main structures

Inner Ear

MRI of the inner ear

MRI now provides considerable detail about the inner ear. The MRI above is done exactly at the level of the 8th (inner ear) nerve. It shows the nerves on both sides emerging from the brainstem, with the cochlea in front, and the vestibule behind. The semicircular canals are not seen on this picture.

MRI of the inner ear

One cut above the MRI above is this image. Here, one can see the lateral semicircular canal (the partial rings). The cochlea is no longer seen as it is lower. The vertical canals are also not seen as they span several "cuts". The can be seen in full with MRI's that are rotated so that the cuts are oriented in the planes of the canals.