Hearing loss imaging at LPCH

  • Hearing loss evaluation requires imaging of the very small structures of the middle ear and inner ear.
  • High resolution MRI of the inner ear allows visualization and evaluation of internal cochlear architecture for the detection of ear malformations or other acquired inner ear damage.

  • Photon counting CT allows the highest resolution imaging available of the middle ear with 0.2 mm slice thickness, providing optimal evaluation of the middle ear ossicles. 

Example: Temporal Bone – Middle Ear Ossicle Anatomy (Normal)

Example: Cochlear Anatomy

  • 2-year-old boy

  • Sensorineural hearing loss 

  • Photon counting CT and thin section MRI

  • Normal cochlear anatomy well demonstrated on CT and MRI

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Axial Photon Counting CT of the left temporal bone through the cochlea

Axial high resolution T2 MRI of the left cochlea

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Previous images magnified

High resolution axial imaging (CT on left, MRI on right) allows visualization of cochlear internal architecture. For example,

  • The thin bony interscalar septum separating the turns of the cochlea from one another (horizontal arrows).

  • The modiolus (vertical arrows) in the central cochlea housing the spiral ganglion nerve cells carrying auditory information to the brain.

Example: 3 Year old boy with sensorineural hearing loss

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Axial Photon Counting CT, 0.2 mm slice thickness images of the right and left temporal bones at the level of the cochleas for inner ear evaluation. Compare to previous normal example.

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Previous images magnified, showing:

  • Incomplete development of the modiolus on both sides (vertical arrows).

  • Absence of the distal interscalar septum creating poor separation between the cochlear middle turn and apical turn (incomplete partition anomaly, horizontal arrows).

  • Enlarged vestibular aqueducts (oblique arrows).

Example: Middle ear Ossicular Prosthesis

  • History of left cholesteatoma removal from the middle ear.

  • Previous left ossicular prosthesis placement.

  • Now with recurrent conductive hearing loss.

Oblique axial, 0.2 mm slice thickness, photon counting CT of the left stapes (arrow) showing good visualization of the stapes superstructure and crura, but the prosthesis can not be visualized extending to the stapes head.

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Oblique coronal, 0.2 mm slice thickness, photon counting CT of the left stapes superstructure (horizontal arrow), which is no longer in contact with the ossicular prosthesis (vertical arrow), due to dislocation of the prosthesis.