0:00

This is an MRI of the brain

0:02

in a three-year old child with developmental delay.

0:05

And there's a nice normal appearance

0:07

of the lateral ventricles,

0:08

appropriate myelination in both

0:11

cerebral hemispheres.

0:13

We're not seeing any issues yet until we get

0:17

down a little bit lower on the right posterior

0:19

aspect of the mesocephalon.

0:21

We see this area of T1 shortening.

0:23

We don't know for certain what this is yet,

0:26

but there's a couple of things we can do.

0:28

One of the things people will sometimes do to

0:30

evaluate a finding is do post-contrast imaging.

0:34

It's still bright on post-contrast imaging,

0:36

but on post-contrast imaging,

0:38

we don't know if this is bright signal from post

0:41

contrast enhancement

0:42

or if it's the intrinsic T1 shortening

0:44

from this finding to begin with.

0:46

However, prior to giving contrast,

0:48

T1 fat-suppressed imaging was performed

0:50

and the bright signal went away.

0:53

That confirms that this is fat,

0:56

and so therefore, it is a lipoma.

0:58

And similarly, on post-contrast imaging,

1:01

the post-contrast bright signal that we see here

1:04

on this post-contrast T1-weighted imaging,

1:07

goes away on post-contrast T1-weighted

1:10

imaging with fat suppression.

1:11

So, therefore,

1:12

this finding has bright signal related to fat,

1:17

which is a small lipoma of the tectal plate

1:20

and is not an enhancing lesion.

1:23

If it did not suppress on fat-suppressed imaging,

1:26

then you have to wonder about other possible

1:28

sources of intrinsic T1 shortening.

1:31

One of the most common ones is subacute blood

1:34

products or methemoglobin.

1:35

In this patient,

1:37

that small area of bright signal

1:39

on T1 weighted imaging was originally raised

1:42

as concern for a hematoma.

1:44

But appropriate use of fat-suppressed imaging

1:48

helped confirm that it was not a hematoma.

1:51

A tectal plate lipoma will often show up at

1:54

either the 5 o'clock or the 7 o'clock position,

1:57

and that's exactly where we see

1:59

it in this individual.

2:01

So, being aware of the normal location

2:04

for this lipoma,

2:06

as well as being aware of the MRI techniques

2:09

you can use to confirm the fatty nature,

2:11

fat-suppressed imaging,

2:13

both pre and post-contrast,

2:14

in this case,

2:15

it allows you to confidently state that this is

2:17

an incidental lipoma that does not require

2:20

follow-up and should have no implications

2:22

to the brain development.