0:01

This is an MRI in a 10-year- old child with headache.

0:05

And we see an abnormality.

0:07

We see an area of bright signal in the posterior

0:09

aspect of the interhemispheric fissure.

0:11

And on the sagittal T1 weighted image,

0:13

we see along the superior aspect

0:15

of the corpus callosum,

0:16

an area that is bright with adjacent

0:19

hypointense signal.

0:21

This sagittal T1-weighted image is performed

0:23

with a gradient technique.

0:25

One of the things you can do is actually use a

0:27

regular spin echo technique and some of this

0:31

susceptibility artifact along

0:32

the edge goes away.

0:34

And you can see this curvilinear area

0:37

of T1 shortening

0:38

bright signal that goes along the

0:41

superior margin of the corpus callosum.

0:44

You can see the normal portions

0:46

of the corpus callosum.

0:47

There's the rostrum,

0:49

the genu,

0:50

the body,

0:51

the isthmus and the splenium

0:53

of the corpus callosum.

0:55

The lipoma follows all the way from the anterior body

1:00

over the isthmus and splenium

1:02

and hooks around the splenium.

1:04

This is likely a lipoma of the corpus callosum.

1:08

But to confirm what it is,

1:11

we use fat-suppressed imaging

1:13

where we keep all other parameters identical.

1:17

And we see that this bright signal

1:19

on T1 weighted imaging goes away.

1:21

This confirms that it's a lipoma,

1:23

that it's just fat.

1:24

An intracranial lipoma is often in the midline

1:27

along the superior margin of the corpus callosum

1:29

is one of the most common places.

1:32

It's considered to be an incidental finding.

1:35

One thing to be aware of,

1:36

as we saw on that gradient T1 weighted image,

1:38

and also on the susceptibility-weighted image,

1:40

you often see susceptibility hypointensity

1:43

along the margins of the colossal lipoma.

1:45

That can be totally normal and that should not

1:48

dissuade you from this being the diagnosis.