0:01

This is the second case of otomastoiditis

0:05

and I want to show one of the potential

0:08

complications of otomastoiditis on this case.

0:12

So, once again, as we scroll through the images,

0:16

we come to the external auditory canal with its

0:20

cartilaginous portion and bony portion.

0:22

Immediately, we start to see that there is opacity within

0:26

the middle ear cavity medial to the tympanic

0:29

membrane. And we see this soft tissue here,

0:32

which is extending from the middle ear cavity into

0:35

the round window niche on the left side.

0:39

You notice also that there is some opacification of

0:41

mastoid air cells and you have the normal variation

0:45

in the size of the mastoid air cells on the

0:47

normal side as well as the left side.

0:51

So looking at this,

0:52

we come to the middle ear ossicles and we see again

0:55

that there is not aeration around the middle ear

0:58

ossicles the way there is on the right side,

1:00

but soft tissue which is also extending

1:04

into the anterior epitympanic space.

1:06

And this is the horizontal portion or tympanic

1:09

portion of the facial nerve coursing right

1:11

by just adjacent to that inflammation.

1:15

So in looking at this, this patient, we would say,

1:18

has evidence of otomastoiditis with middle ear

1:23

cavity opacification and mastoid fluid with a

1:27

fluid level on the left side in the mastoid.

1:30

So it's not until we see erosion of the ossicles or

1:33

displacement of the ossicles or areas of dehiscence

1:36

that we would even raise the specter

1:38

of cholesteatoma. Now,

1:41

cholesteatoma as well as otitis media and otomastoiditis

1:46

usually cause a conductive hearing loss

1:49

because of the fluid that is damping down,

1:53

the ability of the stapes to

1:55

shake or the ossicles to move

1:58

and cause that wave to enter the cochlea.

2:05

So this patient, however,

2:07

had a sensorineural hearing loss.

2:10

So that's unusual for an explanation

2:13

with just otomastoiditis.

2:15

And because of the sensorineural hearing loss,

2:19

the patient also got an MRI scan.

2:23

So I want to show the MRI scan at this juncture,

2:26

the MRI scan was done with both a skull base

2:30

protocol as well as post gadolinium

2:34

enhanced sequences.

2:36

So we'll put this on 2-1-1.

2:39

I'll drag down the CT image as well as

2:45

the post gadolinium enhanced scan.

2:47

So on the post gadolinium enhanced scan,

2:50

and I must admit that this is one month later

2:53

on the post gadolinium axial fat-sat scan,

2:57

you see an awful lot of,

3:00

and enhancement of the mastoid air cells as well

3:04

as extending into the middle ear cavity.

3:07

And some of this mastoid looks more eroded.

3:12

So there's probably an element now of coalescent

3:15

mastoiditis but more importantly on the

3:18

post gadolinium enhanced scan we can see abnormal

3:22

enhancement in the basal turn of the cochlea.

3:26

So here we have the middle and apical turns of the

3:29

cochlea and here we have enhancement in the basal

3:32

turn of the cochlea as well as in the vestibule and

3:37

this is the enhancement in the middle ear cavity

3:40

just adjacent to this and you may actually

3:46

see sometimes enhancement avid enhancement

3:49

of the facial nerve as well.

3:51

So the semicircular canals, little bit worried about

3:54

this posterior crus of the superior semicircular

3:58

canal enhancing more than the anterior crus but

4:02

pretty clearly basal turn of cochlea and the

4:06

vestibule. If we look on the CT image,

4:10

what we're actually looking for is a difference in

4:13

the signal intensity of the CSF between the

4:18

right and left side in the cochlea.

4:20

And this is pretty obvious when we look at the

4:25

right and left side on the same slice.

4:29

So here we have the cochlea with

4:31

its modiolus or mediolus,

4:33

that's the internal skeleton of the cochlea

4:36

with the apical and middle turn and

4:40

basal turn here. And as we look on the left side,

4:45

you see you never have that bright signal intensity

4:48

of CSF-like signal intensity in the basal turn.

4:51

And in point of fact,

4:52

even in the middle turn it is not as bright and

4:57

that's because there's purulent material in there

5:00

and the same thing is true with the vestibule.

5:03

So the vestibule looks nice and bright here and

5:05

clean on the left affected side

5:08

it's kind of grayish.

5:10

It should be all this bright signal intensity but

5:13

doesn't have that same signal intensity and that

5:16

would be indicative on the CT image of the

5:19

inflammation that's occurring in there.

5:21

Much clearly seen on the post gadolinium

5:25

enhanced fat-suppressed scan.

5:27

So we have what looked like on the CT

5:31

scan as otomastoiditis. However,

5:34

upon review of the MRI with post gad fatsat images,

5:38

we now see the patient developed coalescent

5:42

mastoiditis as well as spread to the inner ear

5:45

structures, the basal turn of the cochlea,

5:47

the vestibule, and possibly the one of the ampullae

5:53

of the superior semicircular canal, identifying this as

5:57

labyrinthitis. So inflammation of the internal ear,

6:01

the inner ear structures would be called labyrinthitis,

6:04

and that's one of the complications of

6:08

otomastoiditis, and we'll talk about

6:11

other ones in just a moment.