0:01

Okay, here we have another plain radiograph.

0:04

I think plain radiographs, especially

0:06

in the pediatric population, are very

0:08

difficult to interpret because, you know,

0:10

you've got all these areas of cartilage,

0:13

bowel gases everywhere, you've got a funny

0:16

looking pelvis and the spine and

0:18

everything else, but I think you have to

0:20

try to look for symmetry or asymmetry.

0:23

That's going to be your biggest friend.

0:26

As we look at this, I see

0:27

a subtle difference in symmetry.

0:30

As far as the area in the iliac wing on the

0:33

right, it looks sort of less dense, if you

0:38

will, compared to the contralateral side.

0:40

Looking at the femoral head, this side is a

0:43

little brighter, or sclerotic, or, or what

0:45

have you, and more lucent on this side.

0:47

The question is, which is normal,

0:49

which is abnormal, meaning that, is

0:51

this not bright enough, or is this

0:53

too bright, similarly on either side.

0:56

Whatever the case may be.

0:58

One of those things is abnormal.

1:00

One of those things shouldn't be right

1:01

because it should be relatively symmetric.

1:03

And because of this, we considered some kind of

1:06

an infiltrative process and an MRI was obtained.

1:10

On the MRI, I'm leaving parameters here

1:12

for you just to convince you that I'm

1:14

not lying, that this indeed, the middle

1:17

image here is a T1-weighted image because

1:22

notice the fat is very, very bright.

1:23

Fat is bright here.

1:25

This is the bladder.

1:26

The bladder is dark.

1:27

Fluid is dark on T1.

1:29

But the marrow should be bright on T1.

1:32

Let me blow that up.

1:33

The marrow everywhere.

1:35

The iliac wings.

1:37

The vertebral bodies.

1:39

The femoral heads.

1:41

The femoral shafts.

1:42

Everywhere that marrow should

1:44

be is completely replaced.

1:46

And look at it.

1:47

It's almost the same signal as the muscle.

1:50

This diffuse infiltrative process is complete

1:54

and suspicious for a malignancy.

1:57

And if we look very closely, I'm going

1:58

to show this to you another,

2:00

another view, but there's actually something

2:02

wrong with the margins of this bone also.

2:06

So let's go and look at the STIR sequence

2:09

again to convince you this is not T1.

2:12

The image on your right, it sort of

2:14

looks like a T1 until you look at the

2:15

parameters and you notice that it's a

2:17

fat-suppressed fluid-sensitive sequence.

2:20

In that case, we have lots of edema

2:23

or lots of fluid-like something in the

2:26

marrow of every single bone that we see.

2:28

We know this is a fluid-sensitive sequence

2:30

because the bladder is nice and bright.

2:31

It has fluid in it.

2:33

Remember I told you to take a look along

2:34

the margins of that right iliac wing?

2:36

Well, here is the margin

2:38

of the right iliac wing.34 00:01:23,994 --> 00:01:24,914 Fat is bright here.

1:25

This is the bladder.

1:26

The bladder is dark.

1:27

Fluid is dark on T1.

1:29

But the marrow should be bright on T1.

1:32

Let me blow that up.

1:33

The marrow everywhere.

1:35

The iliac wings.

1:37

The vertebral bodies.

1:39

The femoral heads.

1:41

The femoral shafts.

1:42

Everywhere that marrow should

1:44

be is completely replaced.

1:46

And look at it.

1:47

It's almost the same signal as the muscle.

1:50

This diffuse infiltrative process is complete

1:54

and suspicious for a malignancy.

1:57

And if we look very closely, I'm going

1:58

to show this to you another,

2:00

another view, but there's actually something

2:02

wrong with the margins of this bone also.

2:06

So let's go and look at the STIR sequence

2:09

again to convince you this is not T1.

2:12

The image on your right, it sort of

2:14

looks like a T1 until you look at the

2:15

parameters and you notice that it's a

2:17

fat-suppressed fluid-sensitive sequence.

2:20

In that case, we have lots of edema

2:23

or lots of fluid-like something in the

2:26

marrow of every single bone that we see.

2:28

We know this is a fluid-sensitive sequence

2:30

because the bladder is nice and bright.

2:31

It has fluid in it.

2:33

Remember I told you to take a look along

2:34

the margins of that right iliac wing?

2:36

Well, here is the margin

2:38

of the right iliac wing.

2:40

Here is the margin.

2:41

It's sort of moth-eaten over here.

2:42

I can't follow it.

2:43

And there's stuff outside.

2:46

So there's a collection that's extended

2:48

outside the bone into the periosteum,

2:51

sort of giving us that mottled appearance

2:54

that we saw on the plain radiograph.

2:56

So a biopsy was taken, and this

2:59

was another case of leukemia.

3:01

A very, very infiltrative process that you don't

3:05

want to miss, especially if you know what the

3:08

marrow signal should look like on T1 versus

3:11

a fat-suppressed fluid-sensitive sequence.

3:14

It looks like it's the opposite view in here.