0:00

Let's take a look at the cerebellar vermis on the sagittal

0:03

midline with some magnification.

0:06

Just to get us oriented,

0:07

here's our fourth ventricle with the fastigium of the fourth,

0:09

whose shape and pointedness, and size,

0:12

we pay close attention to.

0:15

Here's the inferior recess of the fourth,

0:17

the floor of the fourth,

0:18

where you'll find the facial colliculus bump,

0:21

the inferior colliculus,

0:21

the superior colliculus, the posterior commissure,

0:24

the habenula and the pineal gland.

0:26

Behind the cerebellum is the straight sinus.

0:29

And above it, the vein of Galen.

0:30

The tentorium cerebelli and the falcotentorial region

0:34

coalesce in this position.

0:36

Inferior to the cerebellum

0:37

is the foramen magnum.

0:39

If we draw a line from the tip of the basion to the tip of

0:44

the opisthion, we like to see the cerebellar

0:47

vermis above that line.

0:49

But it can lie 3 or 4 mm below that line,

0:52

as long as,

0:53

I'll draw it again so you can see it a little better,

0:55

maybe with another color.

0:56

As long as the cerebellum is not compressed,

1:01

is not squished from anterior to posterior,

1:04

and as long as the cerebellar tonsils

1:06

are nice and round,

1:07

rather than being peg-shaped.

1:10

If they're peg-shaped,

1:11

then we have to worry a bit about Chiari malformation

1:14

or one of its lesser variants.

1:16

Now, let's turn our attention in the midline

1:19

to the cerebellar vermis.

1:20

We've got a small structure,

1:23

initially, anterosuperiorly, the lingula.

1:26

Then the next structure is going to be the centrum.

1:30

I'll use yellow for that.

1:32

Then the largest,

1:33

the granddaddy of them all,

1:34

I'll use blue, is the culmen.

1:36

It's the biggest lobe of the cerebellar vermis.

1:40

Then we get into three lobes.

1:42

They're kind of hard to separate them out.

1:45

Here, we've got the declive,

1:47

the folium and the tuber corresponding to this lobe.

1:51

And so, declive, folium, and tuber,

1:53

we'll say declive, folium, tuber.

1:57

Then underneath that and slightly anterior to it,

2:01

we have the pyramis or the pyramidal

2:04

lobe of the cerebellum.

2:06

And then we get into the last two lobes, which we'll use

2:10

light blue for the uvula.

2:12

And then the one all the way anteriorly,

2:15

we'll make a different color just so you

2:17

can pick it out in purple, the nodulus.

2:19

And here is the tonsil of the cerebellum,

2:23

sitting right above the line drawn from the tip of the

2:27

basion to the tip of the opisthion.

2:29

That's the normal anatomy of the cerebellar

2:31

vermis and the sagittal midline.

2:32

Pomeranz out.