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This was a patient who presented with hypoglossal

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nerve palsy on the right side as well as some

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element of Pharyngeal Dysmotility.

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We have a CT scan and MRI scan which show

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the abnormality at the right skull base.

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You notice that the clivus appears to be undercut on

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the right side compared with the normal

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bony anatomy on the left side.

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And in association with that, we have a soft tissue

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mass that's not evident on the contralateral side

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that is present on the right side in that

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parapharyngeal and posterior parapharyngeal space.

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When we look at the associated MRI scan, we see on

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the non-contrast T1-weighted scan the normal bone

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marrow of the clivus on the left side and

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replacement of the bone marrow on the right

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side with low signal intensity.

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So the normal fat has been replaced by this low

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signal intensity tissue, and this low signal

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intensity tissue extends into the parapharyngeal space

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and around the region of where we would expect

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the eustachian tube to be entering.

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So whenever you think about the eustachian tube,

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you have to trace the eustachian tube

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backwards to the middle ear cavity

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and the external auditory canal.

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And this patient did indeed have some inflammatory

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reaction that was present within the

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external auditory canal. So again,

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this is another example of otitis externa

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with the infection occurring within the external

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auditory canal and with spread of that infection of

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the external auditory canal through

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the fissures of Santorini.

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So we described again at the junction of the

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cartilaginous portion of the external auditory canal

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and the bony portion of the external auditory canal.

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We have that little space which is described as the

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fissures of Santorini which

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are oriented on this side.

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We're in the left ear

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in a fashion that leads directly to and along the

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eustachian tube to the skull base which is the

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root of spread of the Pseudomonas infection.

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In follow-up on this particular case,

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the patient developed an abscess which is identified

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on this post-gadolinium coronal MRI scan.

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Here are the mastoid air cells which are opacified

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and showing contrast enhancement.

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Here is just a little bit of meningitis dural-based

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enhancement associated with the mastoiditis.

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And here is the abscess formation below the mastoid.

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And this is.

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What we would term the bezold.

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I don't know whether it's a T.

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Besold abscess

3:07

of mastoiditis in association with osteomyelitis

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and cellulitis at the skull base,

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which you're seeing a little bit here from malignant

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otitis externa or malignant external otitis (MEO).

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I like malignant otitis externa.

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So another example of this very dangerous,

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dangerous infection.