Learning objectives
Provide an anatomical overview of inner ear structures.
Describe the CT and MR imaging features of inner ear malformations by using a standard classification system.
Background
Sensorineural hearing loss in children is a major cause of disability.
Its early diagnosis is very important since delayed diagnoses may affect the development of language,
the academic skills and social and emotional development.
It can be due to congenital or acquired anomalies; at least half of them have a genetic origin and among the acquired ones the infection due to cytomegalovirus is the most common cause.
Congenital sensorineural hearing loss can be divided intotwo categories.
The majority ofwhich are membranous malformations.
Here,
the pathology...
Findings and procedure details
Procedure details:
CT examinations
High-resolution CT of the temporal bone,
followed by image reconstruction in both the axial and coronal planes,
is required to evaluate the inner ear and its malformations.
Axial scanning is performed in planes parallel to the infraorbitomeatal line from the top of the petrous apex to the inferior tip of the mastoid bone.
Coronal reformatted images are obtained from the anterior margin of the petrous apex to the posterior margin of the mastoid.
MRI Examinations
The use of a 1.5- or...
Conclusion
Imaging plays an important role in the evaluation of congenital sensorineural hearing loss.
CT and MR imaging provide excellent delineation of the intricate anatomy of the inner ear: CT depicts the minute details of osseous structures,
and MRI allows visualization of the fluid-filled spaces and the vestibulocochlear nerve.
Together,
these complementary modalities can aid decision making about the best management strategy by facilitating the identification and characterization of inner ear malformations and any associated neurologic abnormalities.
A broad spectrum of inner ear malformations have been...
Personal information
Dr Rola Zayed,M.Sc
Fellow in training,
Ain Shams University,
Cairo,
Egypt.
Email: rola
[email protected]
References
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Donaldson JA,Duckert LG,Lambert PM,Rubel EW.Surgical anatomy...