0:00

I want to take a moment to talk about the

0:02

skeleton on the sagittal midline view

0:05

since everybody gets a sagittal midline view for brain MR.

0:08

We've got the diploic space

0:11

which has variable amounts of fat in it,

0:13

especially in the midline where

0:14

it's pretty much devoid of fat

0:16

as you frequently volume average the sagittal suture and

0:20

the sutural volume averaging can produce

0:23

this little dotted appearance.

0:24

I'll make it a little lighter so you can see it,

0:26

of the diploic space.

0:27

You've got an inner table,

0:29

an outer table, and then the galea, which is visible inferiorly,

0:33

but superiorly, it hugs the outer table,

0:35

so it's hard to separate out the galea unless

0:38

it's lifted off by a subgaleal hematoma.

0:40

Here is the superficial fascia of the scalp.

0:44

There's the skin, and here's some subcutaneous fat.

0:47

Then we have the tip of the basion and the tip of

0:51

the opisthion, which define the foramen magnum.

0:54

Then we've got the anterior button of C1,

0:57

the atlantodental interval,

0:59

which we pay careful attention to

1:00

in rheumatoid arthritis,

1:01

and the tip of C2.

1:04

And there are some membranous and ligamentous structures

1:07

we'll tackle in the cervical spine talk and vignette.

1:11

We've got the anterior arch of C1,

1:12

as mentioned, and the posterior arch of C1,

1:15

the posterior arch of C2.

1:17

Don't forget to look at the sphenoid sinus and the frontal sinus.

1:22

The clivus is a particular area of consternation.

1:25

You can have synchondrosis here.

1:28

You can have bone islands here.

1:29

You can even have recruitment of red

1:31

marrow in this flat bone structure.

1:33

And sometimes that may produce some consternation

1:36

when you're considering the diagnosis

1:38

of metastatic disease.

1:40

However, typically, red marrow fades

1:42

or becomes less bright on the T2-weighted image.

1:45

And when you inject it and do first-pass imaging or

1:48

delayed contrast imaging, the enhancement is little to

1:52

scant, and that will help you differentiate it from

1:54

something of importance or significance.

1:57

We're going to tackle, in its entirety, the brainstem

2:00

skeletal anatomy in another series of vignettes.

2:03

Pomeranz out.