Learning objectives
To be able to recognize the different middle ear compartments on MR imaging: the middle ear can be easily analyzed on MRI,
on axial and coronal sections using some anatomical landmarks.
Anatomical specimens of dry temporal bones sections in coronal and axial views are compared to CT sections and MR equivalent images to present the MR landmaks,
delineating the different compartments of the tympanic cavity
Background
If the middle compartments are easily located on CT,
they are delineated with more difficulties on MR eventhough the gold standard for postoperative follow-up of cholesteatoma is MRI.
A precise localization of a lesion in the tympanic compartments,
helps the surgeon for his/her preoperative planning,
during surgery and for the follow up.
Findings and procedure details
We propose an easy way of reading of middle ear compartements on MRI images without the need of CT/ MR superposition.
MRI protocol :
- axial images are directly acquired in a plane parallel to the orbital roof.
This plane is parallel to the lateral semicircular canal.
- coronal sections are perpendicukar to the axial ones.
The middle ear is divided in three different compartments on the coronal section: From the top to the bottom:
- Epitympanum (E)
- Mesotympanum (M)
- Hypotympanum (H)
The...
Conclusion
A precise localization of a lesion in the tympanic cavity is very important before surgery.
MRI is often the only way to document precisely a lesion particularly in the field of recurrent cholesteatoma.
The radiologist must learn how to exactly and easily localize a lesion in the middle ear.
With this MRI reading technique,
there is no need to superimpose CT and MRI anymore
Personal information
Ms Aïna Venkatasamy,
Radiology resident,
Strasbourg University Hospital,
Strasbourg - FRANCE
[email protected]
Professor Francis Veillon,
Professor of Radiology,
Departement of Radiology 1,
Hôpital de Hautepierre,
Strasbourg University Hospital,
Strasbourg - FRANCE
[email protected]
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