0:02

Hello and welcome to Noon conferences hosted by MRI Online.

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In response to changes happening around the world

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right now and the shutting down of in-person

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events, we've decided to provide free daily

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noon conferences to all radiologists worldwide.

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Today, we're joined by Dr. Narendra

0:16

Shet for a lecture on pediatric adrenal lesions and mimic.

0:20

Dr. Shet is a pediatric radiologist at Children's

0:23

National Hospital and serves as both a director

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of Body MRI, and the program director for

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the Pediatric Radiology Fellowship program.

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Uh, that being said, thank you

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guys so much for joining us today.

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We hope you enjoy this conference.

0:36

Dr. Shet, I'll let you take it from here.

0:39

All right.

0:39

Thank you very much.

0:40

Um, so, uh, it's my pleasure to be here today.

0:43

I'll talk with you about pediatric adrenal lesions

0:46

and mimics. Um, we'll review some of the imaging

0:50

that can be done for the pediatric adrenal gland,

0:52

um, as well as, uh, some of the, um, the normal

0:57

appearance of the adrenal gland, and then go over

0:59

some cases of true lesions, as well as mimic lesions.

1:05

So, um, adrenal lesions in pediatric

1:08

patients can come from a variety of causes.

1:10

Uh, some inborn, some acquired. Um, these

1:14

can be asymptomatic, but some of them may

1:16

present with pain or and/or palpable masses.

1:20

So, in terms of imaging in the neonate, um, or in the

1:25

fetal period, for that matter, um, ultrasound and MR

1:27

are, um, are.

1:30

Good modalities for imaging.

1:31

The adrenal gland. Uh, ultrasound can be done

1:34

postnatally as a first-line imaging test.

1:36

An MR is typically reserved for

1:38

equivocal cases, uh, in older children.

1:40

Ultrasound, again, is a first-line modality.

1:42

Um, CT or MR can be done for better characterization,

1:45

uh, particularly if there's a concern for an

1:47

adrenal mass and if there is an underlying mass.

1:50

Nuclear medicine studies, um, as I'll discuss in

1:53

several cases, can be helpful for mass characterization.

1:57

It's important that we don't, uh, overuse nuclear medicine

2:00

as, um, uh, due to radiation considerations in children.

2:03

But there are some, uh, really helpful uses

2:07

for particular nuclear medicine, um, studies.

2:12

So this is the normal adrenal gland, and we'll

2:14

talk about how it appears in different modalities.

2:18

So this is typical ultrasound of a neonate.

2:20

Uh, there's a normal trilaminar appearance.

2:24

To the adrenal gland.

2:25

Uh, you can see that the dark outer

2:27

portion is the hypoechoic cortex.

2:31

The bright central portion is the

2:34

hypoechoic medulla, and this is the medulla.

2:38

And then the dark, um, further central structure is the

2:42

hypoechoic cortex again, and you can see here that above

2:45

the neonatal kidney, that this is an inverted Y shape.

2:51

So ultrasound can be used, uh, to look at the adrenal gland.

2:53

And the adrenal gland is typically fairly large in

2:56

the neonatal period, uh, due to hormone stimulation,

2:59

and then it slowly diminishes in size over time.

3:03

This is a typical CT appearance, a coronal

3:06

reconstruction showing an adrenal gland.

3:08

Uh, you can see there on the left

3:09

again, that inverted Y shape.

3:12

And then this is just the normal adrenal gland

3:15

on MR. Uh, this is actually a patient with

3:17

sickle cell disease, which is why their kidneys

3:19

look a little bit, uh, dark in the cortex.

3:22

But this is a normal inverted Y shape, uh, of

3:24

the adrenal gland in the, um, in an adolescent.

3:29

So we'll jump into some cases, um, just with that context

3:32

of understanding what a normal adrenal gland looks like.

3:36

So this is a five-year-old male with left leg pain.

3:40

So the patient presents and, um, got

3:44

a series of hip radiographs, and.

3:47

The, uh, if you remember, the indication was left leg pain.

3:50

And what you can see here is that the left leg, the

3:54

left proximal femur, certainly does look abnormal.

3:56

There's heterogeneous mineralization in the proximal

3:59

femur, and if you look very closely, you can see that

4:02

there's some periosteal reaction along the femur.

4:05

Now.

4:06

Anytime you see periosteal reaction, um, your consideration

4:09

should be that there's a history of trauma, um, a

4:12

history of infection or a history of underlying neoplasm.

4:17

And in this case, the bone mineralization

4:21

is a little bit unusual as well.

4:22

So trauma is probably off the table.

4:24

So what your considerations would be

4:26

would be, um, infection or neoplasm.

4:31

And given, um, this appearance.

4:34

The, and the clinical presentation is screened elsewhere.

4:39

And looking in the abdomen, you can see that

4:40

there's outlined by cursors a, um, heterogeneously,

4:45

isoechoic, uh, mass in the left upper quadrant.

4:49

And this was an MR that was subsequently done.

4:51

And this is a contrast-enhanced image, and you

4:53

can see there much more clearly a well-defined,

4:56

uh, rounded suprarenal mass on the left.

4:59

Which has heterogeneous enhancements, generally

5:02

hypoenhancing, but there are some areas

5:03

that are fairly, um, fairly well enhancing.

5:09

So I'll just give you a few seconds

5:10

to think about this question.

5:11

So, which of the following is not typical of neuroblastoma?

5:14

Neuroblastoma typically encases

5:16

vessels, rather than invading them.

5:18

Choice B, common locations for metastatic

5:20

neuroblastoma include the liver and the bone marrow.

5:23

Choice.

5:23

C, neuroblastoma is typically

5:25

followed with PET, and is, it is not

5:27

MIBG avid.

5:29

Or choice D, the primary site of involvement

5:31

can be outside the adrenal gland.

5:33

So think about that for a few seconds.

5:38

Alright, and so the answer is choice C, um, and

5:42

one of the things that we'll discuss is the role

5:44

of nuclear medicine in MIBG, um, in, uh, treatment.

5:49

And so, um, will.

5:53

Discuss where, um, MIBG can be particularly helpful,

5:56

and most of neuroblastoma is in fact MIBG avid.

6:01

So neuroblastoma is the third

6:02

most common pediatric malignancy.

6:04

It's, um, most commonly in.

6:07

The most common ones are actually leukemia

6:09

and CNS malignancies, but it can be associated

6:12

with several syndromes, um, as noted below.

6:14

And the median age of presentation is 22 months.

6:17

And this is important to remember, um, when considering

6:20

pediatric abdominal masses, 'cause the age can be helpful

6:23

in terms of stratifying your differential diagnosis.

6:29

So in terms of the clinical presentation, often

6:31

it's, uh, abdominal pain or palpable mass, but

6:34

they can present with non-specific B symptoms, um,

6:37

such as malaise or weight loss, or in this case,

6:39

uh, metastatic disease presenting with leg pain.

6:42

Um, they can have focal.

6:44

Neurologic deficits.

6:45

Um, and one of the things that we'll discuss

6:47

is, um, neuroforaminal extension and how that

6:50

generally reflects, um, advanced disease.

6:53

Uh, one of the unique presentations of neuroblastoma

6:55

is what's called opsoclonus myoclonus, which

6:57

is the paraneoplastic syndrome, um, with.

7:00

Some, uh, eye movements, as well as, uh, muscle jerks.

7:04

It affects two to 3% of neuroblastoma patients.

7:06

But that clinical presentation, uh, usually

7:09

alerts clinicians that they want to work the

7:12

patient up for a, uh, possible neuroblastoma.

7:17

So I'll just present this here, um, as an older staging

7:20

system, and this is the International Neuroblastoma

7:23

Staging System, um, that you may encounter.

7:26

'Cause this is the classic, uh,

7:28

stratification of neuroblastoma.

7:30

But stage one is typically a localized tumor, uh, with some

7:34

complete, with a complete gross resection. Stage two, two A,

7:38

and two B are both, uh, have incomplete resection.

7:42

Um, two B, the difference being whether

7:45

or not its lateral lymph nodes have tumor.

7:47

Stage three is if the lesion's unresectable

7:50

and it's extending across midline.

7:51

And midline is an important thing to

7:53

remember, as that's one of the distinguishing

7:55

features that's typical of neuroblastoma.

7:58

Stage four is where there's dissemination to, uh,

8:01

distant nodes, marrow, skin, liver, other organs.

8:04

And then four S is one that I've included at the bottom,

8:07

um, as a unique subtype, but it's infants less

8:09

than 1-year-old, um, who have skin, liver, and marrow

8:13

metastases, but there's near a hundred percent survival.

8:17

So in terms of staging updates in 2008,

8:20

the, uh, International Neuroblastoma

8:21

Risk Group staging system, um, was used.

8:26

Uh, published their new criteria.

8:28

And this is used with the old INSS

8:31

staging that I just showed you.

8:33

Um, the main thing to remember is that this new

8:35

system focuses actually more on the pre-treatment

8:37

evaluation rather than the post-surgical.

8:39

So if you remember when I was discussing the, um, the

8:43

old staging system, it had to do with resectability.

8:45

And so that's usually a post-surgical evaluation.

8:48

Um, the new system focuses more

8:50

on the pre-treatment evaluation.

8:52

Um, one of the things that.

8:53

This new system uses is what's called

8:55

image-defined risk factors, or IDFs.

8:59

Um, so there is a long list of them, but, um, some

9:02

of the take homes are, um, assessing whether or not

9:05

there's tumor, neural, or vascular encasement.

9:09

Um, there's tumor extension between multiple body

9:12

compartments, um, or if there's intraspinal extension.

9:17

So this is, uh, taken from a, uh, an excellent

9:20

Radiographics article from 2018, um, highlighting some

9:23

of the updates in neuroblastoma treatment and management,

9:27

as well as diagnosis, uh, and showing the different

9:30

stages of, um, in the, uh, INRGSS staging system.

9:37

And you can see here that they do, um,

9:40

utilize the role of IDRFs, and they've separated

9:43

them out into four different criteria.

9:47

So now shifting gears, we'll talk a little bit more about

9:53

the staging system, and we'll talk a

9:58

little bit more about the imaging.

9:59

So on radiographs, radiographs typically, and

10:02

I didn't really allude to this before, but

10:04

radiographs are typically not particularly

10:06

helpful when evaluating for adrenal lesions.

10:08

Um.

10:10

Mainly because you can't really see them very well.

10:12

That being said, uh, if there are calcifications

10:15

associated with the adrenal gland or

10:17

with a mass, they can be appreciated.

10:19

The more notable thing that you may see on

10:21

radiographs and neuroblastoma is that there's

10:23

mass effect, uh, upon the adjacent solid organs.

10:26

In bowel, calcifications are typically noted in about

10:30

a third of cases of neuroblastoma on radiographs.

10:33

They're much more clearly seen on CT.

10:35

If there is osseous metastatic disease, as I

10:37

mentioned before, you can expect to see periostitis.

10:40

Um, the other feature of the underlying bone is

10:42

that you may see permeative lucency involved.

10:47

So on ultrasound, uh, you typically see a

10:49

heterogeneously hypoechoic adrenal mass.

10:52

Um, or in our case it was more isoechoic.

10:55

Um, the important thing is the heterogeneity.

10:57

Um, hypoechoic foci typically reflect the presence of

11:00

hemorrhage or necrosis, and then hyperechoic foci typically

11:05

represent calcifications, which may or may not shadow.

11:08

Um, CT and MR are usually done to really.

11:11

Uh, visualize the extent of the, uh, primary lesion and.

11:17

As I noted before, um, the neuroblastoma typically does

11:21

cross midline, uh, calcifications are best seen on CT, so

11:24

in about 75% of cases, calcifications can be appreciated.

11:28

Uh, on MR, these tend to be T1 hypointense

11:32

with, um, T1 hyperintense foci represent the

11:35

areas of hemorrhage, and generally they're T2

11:38

hyperintense, though they're often very heterogeneous.

11:40

Um, an important feature is that there's typically

11:42

encasement of vessels rather than invasion of vessels.

11:45

An MR is superior for demonstrating neuroforaminal

11:49

extension and also, um, to identify marrow involvement.

11:55

So this is just a typical example of a CT, and you

11:57

can see here there's a midline mass that's, um,

12:01

there's a mass that's extending across midline.

12:04

It's clearly encasing some vascular structures.

12:06

And you can see here this is the aorta.

12:08

As well as the right renal artery.

12:09

And you can see that there's foci,

12:11

necrosis in this hypodense area.

12:14

This is just a similar, um, similar imaging-wise,

12:19

uh, case on MR, where you can see that there's, uh,

12:22

clearly encasement around the aorta, but preservation

12:25

of the flow void, um, and it's crossing midline.

12:31

So shifting to, uh, nuclear medicine, uh,

12:34

MIBG is, um, particularly helpful, 'cause there's avid

12:38

uptake in about 90% of neuroblastoma due to, uh,

12:41

the presence of a norepinephrine transporter.

12:44

Um.

12:45

One thing to keep in mind is with, uh, MIBG studies,

12:47

as well as with any, uh, scintigraphy studies, is

12:50

to remember the normal physiologic distribution.

12:53

So on scintigraphy, you should see uptake

12:56

of MIBG in the salivary glands, liver,

12:58

the spleen, the heart, and the bladder.

13:00

And I'll show you an example, um, actually of that MR

13:02

case that I just showed you, uh, and the distribution

13:06

of MIBG on that, um, on that subsequent study.

13:09

So, uh, the challenges in the

13:12

subset of patients in neuroblastoma.

13:15

That's not MIBG.

13:16

It's so about 10% of patients, uh, classically,

13:19

FDG PET was used in metastatic evaluation.

13:22

Um, recently though, uh, gallium DOTATATE has been used,

13:26

um, it's a somatostatin analog that's been used in, um,

13:29

in adults and now has started to be used in neuroblastoma.

13:33

Um, the advantage of this over PET is that there's

13:35

typically greater image resolution than with, um, with FDG.

13:39

If lesions are not MIBG avid, um, in general, um,

13:43

bone scans are done in conjunction to evaluate

13:45

for bone metastases, but it can be challenging to

13:47

interpret these, um, due to the presence of normal

13:49

physiologic uptake given that they are skeletally immature.

13:54

So this is just, uh, that case that I, uh,

13:56

showed you before with the MR, and you can

13:58

see the normal physiologic distribution.

14:00

There's heart, there's salivary gland, there's liver, a

14:03

little bit of spleen, and then there's, um, the bladder.

14:05

And then you can see that this,

14:07

uh, the mass is pretty avidly,

14:09

um, taking up MIBG.

14:12

And this is an anterior image, and this is a posterior image.

14:17

So I did wanna mention the, um,

14:19

possibility of extra-adrenal neuroblastoma,

14:21

'cause actually, um, even though adrenal is the most common

14:25

single location of neuroblastoma, um, extra-adrenal sites

14:29

represent actually almost two thirds of neuroblastoma.

14:33

So the extra-adrenal retroperitoneum, um, is

14:36

almost as frequent as the, um, as the adrenal

14:40

gland, as a site of neuroblastoma, and the posterior

14:42

mediastinum is a, uh, another common location.

14:44

Um, one thing that I do want to take away from the

14:47

lecture is that, um, if you have a posterior mediastinal

14:50

mass in a child, three and under, um, it's typically

14:53

considered neuroblastoma until proven otherwise.

14:56

Um, some less common sites of involvement

14:58

include the, uh, the pelvis and the neck.

15:01

So this is just a companion case, um, where you see

15:04

again, a large mass, um, this one is not crossing midline.

15:07

This one has something of a claw sign on the right kidney.

15:12

And you can see here that there's expansion of the IVC,

15:15

and it's not just the IVC that's expanded, but it looks

15:18

like there's soft tissue, um, that's expanding the IVC.

15:22

So this is just an example of a Wilms tumor.

15:24

Um, and the reason I bring this up is that it is the

15:27

main differential that you have when

15:29

you're thinking about a renal or SRE mass.

15:31

Um, so Wilms is the most common pediatric renal mass.

15:34

It's the most common abdominal mass

15:35

in children, one to eight years old.

15:38

It's typically older, um, children who are affected

15:41

compared to those with neuroblastomas at the peak age.

15:44

For Wilms tumors, typically three to four years old.

15:47

And as far as imaging features, uh,

15:49

Wilms tends to not cross midline.

15:51

Um, it tends to not have calcifications.

15:53

It tends to invade into vessels and causing

15:55

tumor thrombus, as in this case, and they tend

15:58

to have metastatic disease, um, to the lungs.

16:01

So this is just a summary chart showing some

16:03

of the features to keep in mind when you're

16:05

thinking about neuroblastoma versus Wilms.

16:08

Remember, um.

16:10

Uh, one thing I didn't, uh, allude to, but, um,

16:13

just keep in mind, again, metastatic involvement.

16:16

Neuroblastoma, you typically encounter liver,

16:18

bone, and skin, whereas Wilms, typically lungs.

16:22

Um, I'll skip a lot of treatment stuff just

16:25

because, um, there's still a lot of, um, a

16:29

lot of considerations in, uh, and novel things

16:33

occurring in the treatment of neuroblastoma.

16:35

Um.

16:36

Typical mainstays of treatment include, uh, neoadjuvant

16:39

chemotherapy to make the tumor resectable, and

16:42

then, um, ideally, um, resection of the lesion.

16:46

And then, uh, if in the absence of that, um, other

16:50

alternatives can be, uh, bone marrow transplant.

16:53

Um, one of the recent things that's occurred, um, is

16:56

to use the principle of the MIBG avidity of the lesion

16:59

and use, um, MIBG as a, uh, as a means of treatment,

17:04

which is being done in a few centers around the country.

17:09

So, um, this is a second case.

17:11

This is a one-year-old with a history of

17:13

prematurity who presents with failure to thrive.

17:18

So what you can see on this radiograph here is that

17:22

there's something going on in the left upper quadrant.

17:26

Um, as you can see, there's mass effect, which

17:29

is, uh, one of the things I had mentioned

17:31

before as a, um, as a consideration for, um.

17:35

When you see neuroblastoma on radiographs.

17:38

So next modality is ultrasound.

17:42

What you can see here is, um, this is a sonographer

17:45

who wasn't quite sure what exactly we were seeing here

17:47

because there's a spleen with question marks, but you

17:50

can see that this is the measurement for the spleen.

17:52

Um, and then there's something below the spleen.

17:55

And so this is two measurements.

17:58

Of what's this sort of homogeneously,

18:01

hypoechoic, mass in the left upper quadrant.

18:04

Um, given the failure to thrive and, um, this

18:06

mass effect, the suspicion was for neuroblastoma.

18:11

So the patient had undergone an MR. And if you can see

18:14

here on the, uh, this T2-weighted image at left and this

18:18

post-contrast image on the right, there's actually nothing.

18:21

There's no pathologic mass that we can see.

18:23

Um, there's a spleen.

18:25

It's kidney, and there's nothing,

18:27

really nothing in the SRE region.

18:30

Looking at some additional images, you can see here

18:32

that there's some, uh, hyperintense stool on T1,

18:36

and you can see that there's a fairly abundant amount,

18:39

and you can appreciate that there's mass effect upon

18:42

the bladder by this distended structure here, which

18:44

is actually the rectum that's filled with stool.

18:47

And so they, um.

18:49

Given that, um, and, and sorry, that wasn't the rectum,

18:53

that was actually the sigmoid that was filled with stool, and

18:56

given that presentation, um, the worry was that there might

19:00

actually be, um, some pathologic cause of constipation.

19:03

And so contrast enema is done, and you can see here

19:06

that the rectosigmoid ratio is actually inverted.

19:09

Um, so in typical, in, uh, most cases, and normal, um.

19:15

Contrast enemas,

19:16

the rectum should be more distensible than

19:17

the sigmoid, and in this case, it's reversed.

19:20

So this is actually a late presentation of Hirschsprung's

19:22

disease, which had a, which is a, uh, was

19:24

a mimic for the adrenal, for an adrenal lesion.

19:27

Um.

19:29

It's important to remember when thinking about

19:31

Hirschsprung's disease, that we typically

19:32

do think about it in the neonatal period.

19:34

But, um, while 90% of cases present in the

19:36

neonatal period, 10% of them present later,

19:39

um, typically with chronic constipation.

19:41

Um, but they may present with complications

19:43

such as, um, Hirschsprung's-associated enterocolitis,

19:45

um, the common teaching that, um, that.

19:50

Pediatric radiologists give to trainees

19:52

as regarding the rectosigmoid ratio.

19:54

And so that's what we look for on lateral images.

19:57

In contrast enemas, typically the

19:58

rectosigmoid ratio is greater than one.

20:01

Um, and in short-segment Hirschsprung's disease,

20:04

which is the most common type, it's less than one.

20:07

Um, and remember, fluoroscopic findings in general are

20:11

going to be suggestive, but not necessarily diagnostic.

20:14

Um, rectal biopsy needs to be done to

20:17

make that confirmation of Hirschsprung's.

20:21

So we'll shift to, uh, a different, uh, different

20:24

lesions that you can find within the adrenal gland.

20:26

So this is a newborn with antenatal

20:29

follow-up for, uh, renal ectasis.

20:33

And so this is an ultrasound that was done.

20:35

Um, the ectasis, the, uh, kidneys were evaluated, and the

20:40

sonographer picked up on, in the left adrenal gland.

20:44

There was a lesion.

20:46

And you can subtly appreciate normal

20:49

adrenal morphology and cortex.

20:52

But there's also this heterogeneous lesion in the

20:56

left adrenal gland, which has some echogenic portions

20:58

and some, um, more hypoechoic or anechoic portions.

21:04

And so an MR was done just given.

21:06

The nature of that lesion.

21:08

Um, one thing I didn't mention, but there is,

21:10

um, some color flow that was, uh, appreciated

21:13

within that site, which is, uh, why MR

21:16

was done.

21:16

Um, given this appearance, the suspicion

21:19

was that this was a neuroblastoma.

21:22

So this is a, uh, gradient echo T1-weighted

21:25

sequence that shows that there's a light-bulb,

21:28

bright lesion in the, um, left adrenal fossa.

21:32

And remember, light-bulb bright is a buzzword

21:35

that we use, um, and in a different, uh,

21:37

adrenal lesion that I'll talk about later.

21:39

But in that lesion, it's

21:42

typically T2 that's referred to.

21:43

And this is a T1-weighted sequence.

21:45

So on T1, um, there's only a few

21:47

things that really should be, uh.

21:50

Bright, um,

21:52

blood,

21:53

being one of them.

21:54

Um, other things to consider would be melanin, um,

21:57

calcium, um, proteinaceous material, fat, um, as well as gadolinium.

22:05

So this is just an example of a neonatal adrenal hemorrhage.

22:08

Um, so the adrenal gland in the neonate is at

22:12

increased risk of hemorrhage due to its large size,

22:14

its vascularity, and usually there's some

22:16

underlying condition that causes the child to

22:18

have a hemorrhage, either, um, traumatic delivery,

22:22

um, sepsis, um, hypoxia, coagulopathy, shock.

22:26

And in the prenatal period, typically,

22:29

adrenal hemorrhage is not common.

22:31

More commonly, they occur on the right than left.

22:33

The, um, the underlying thought is that

22:35

the, um, right adrenal vein is that there's

22:39

compression between the kidney and the liver.

22:41

But another proposed thought is that the right

22:42

adrenal vein connects directly to the IVC.

22:45

That's more prone to, um, to

22:48

spasm or thrombosis in the setting of neonatal stress.

22:51

And then the left adrenal vein, um, these

22:53

can occur bilaterally in about 10% of cases.

22:56

And the overall incidence of neonatal adrenal

22:58

hemorrhage is about one to two in a thousand.

23:03

So in radiographs, um, you can see calcifications,

23:06

and these typically conform to the shape of the,

23:10

uh, adrenal gland, although they don't have to.

23:12

But that's typically a finding

23:14

that's in very remote hemorrhage.

23:17

Um, otherwise there really shouldn't be any manifestations

23:20

on radiographs for neonatal adrenal hemorrhage.

23:23

Uh, the mainstay of workup is ultrasound.

23:25

Um, and the appearance of the hemorrhage really

23:28

depends on the age of the blood products.

23:29

So typically when a hemorrhage is acute, it's echogenic,

23:34

and as it becomes subacute, it becomes more and more liquid.

23:36

Um, and, and it has, uh, correspondingly

23:40

a more cystic appearance.

23:41

Um.

23:42

If it's a remote hemorrhage, you may or

23:44

may not see the calcifications again.

23:46

Um, you may appreciate them on

23:47

radiographs. Uh, color Doppler,

23:50

um, typically they should be avascular as opposed

23:54

to neuroblastoma, which is really the main thing

23:56

that, um, that is a differential consideration.

24:00

That being said, because these are

24:03

occurring within the adrenal gland,

24:04

it's possible that you may get some vascular

24:06

flow, um, artificially from adrenal tissue

24:09

that's, um, that's within your, um,

24:12

within your color box on Doppler.

24:15

So this is an example of an acute adrenal hemorrhage.

24:18

And you can see here that this

24:21

is fairly uniformly hyperechoic.

24:23

And again, as I mentioned, you can see that

24:24

normal trilaminar appearance of the adrenal gland.

24:27

Um, so this is unaffected tissue.

24:29

And then within the adrenal.

24:31

Itself, there is this, uh, hypoechoic hemorrhage.

24:35

So as the hemorrhage ages, it becomes more

24:37

and more hypoechoic and liquid over time.

24:39

And so this is a chronic or remote

24:42

neonatal adrenal hemorrhage.

24:45

So MR, um, as I mentioned, it's

24:47

used, really used in atypical cases.

24:49

If there's some suspicion that

24:51

there's congenital neuroblastoma.

24:52

Um, and the appearance, like on ultrasound, is really, um.

24:59

Depends on the age of the blood products.

25:01

So acute hemorrhage tends to be T1 bright, and chronic

25:03

hemorrhage typically has a T2, uh, dark hemosiderin rim.

25:07

Uh, the enhancement features are not really very reliable.

25:10

Um, and as a, um, as an aside, we typically

25:14

try not to give, um, gadolinium in the first 30

25:17

days of life to, um, to neonates, uh, just because

25:20

they have generally depressed renal function and

25:23

with all the concerns for gadolinium deposition.

25:26

Um, you know, if avoidable, we try to avoid

25:29

contrast administration in the neonatal period.

25:34

As far as management goes, um, as I mentioned there,

25:37

you know, it can be very difficult to differentiate

25:39

these two, um, particularly when you have an

25:42

evolving adrenal hemorrhage, which looks cystic

25:44

and solid, much as a, um, as a neuroblastoma would.

25:47

So the recommendation typically is that, uh, short

25:51

interval repeat ultrasound, in four to six weeks, be done.

25:54

Um.

25:55

Because if it's neuroblastoma, it typically will

25:58

enlarge and become more complex over four to six weeks.

26:01

And, uh, management really should not be affected too much.

26:05

Whereas, uh, hemorrhage should decrease in size

26:08

and echogenicity in that four to six week period.

26:10

Um, and some people will, uh, suggest, too, that the, uh,

26:15

four- to six-week period be repeated, um, so that we can,

26:19

these can be followed until they are, uh, no longer visible.

26:24

This is just a related case.

26:26

Um, you can see here that the circle is

26:28

outlining this is the right adrenal fossa.

26:31

There's something that's hyperdense on CT, on

26:34

an unenhanced CT, um, that bright structure in

26:37

the, uh, left upper quadrant is an enteric

26:39

tube, but there's a hyperdense structure on an

26:42

unenhanced CT, which makes you think of hemorrhage.

26:44

So this is a right adrenal hemorrhage.

26:47

Um, however, in this case, you can appreciate

26:50

that there's a liver laceration and a, um.

26:56

And a focus of active hemorrhage.

26:58

And there's a right renal laceration as well,

27:02

as a perinephric hematoma, also with active hemorrhage.

27:06

Um, and this was a, this was subsequently done as a

27:10

contrast-enhanced study in that same patient from before.

27:13

And so this is an example of a traumatic adrenal hemorrhage.

27:16

Um.

27:17

In older pediatric patients, adrenal

27:19

hemorrhage is usually related to blunt trauma.

27:20

This was a non-accidental trauma.

27:23

Um, some other things that you can consider for

27:25

pediatric adrenal hemorrhage in older kids would

27:27

be coagulopathy, vasculopathy, or meningococcemia.

27:33

Okay?

27:34

This is a 17-year-old female who presents with pretension.

27:40

Okay?

27:41

And you can see a nice, normal-looking left kidney.

27:46

However, medial and superior to the left kidney,

27:49

there's a well-defined, uh, lesion that measures

27:55

about four by three by three centimeters, and

27:58

CT was done to better characterize

28:02

this, and you can see that there's a fairly.

28:07

Homogeneous, a little bit heterogeneity to it, but, uh,

28:10

avidly enhancing lesion in the, um, left SRE space.

28:17

Um, and, uh.

28:20

I wanna shift gears and just have you think about this

28:22

question, because this will give away to you probably what

28:25

this, uh, this lesion is, but which of the following is

28:28

not associated with von Hippel–Lindau syndrome: renal cell

28:31

carcinoma, renal cysts, pheochromocytoma, or adrenal cysts?

28:38

Right?

28:39

Think about that for a few seconds.

28:44

All right.

28:44

And the answer is choice D, adrenal cysts.

28:49

So this was a pheochromocytoma.

28:51

They're typically hypervascular, secrete

28:54

catecholamines, uh, and arise from the organ of Zuckerkandl.

28:59

Um, and the retroperitoneum is typically the

29:00

most common location, uh, if it's extra-adrenal,

29:04

um, but many of them arise from chromaffin and

29:07

tissue, uh, in the adrenal glands themselves.

29:11

The rule of tens is that 10% of them are in children,

29:15

10% are bilateral, 10% are malignant, 10%

29:18

are outside of the adrenal, and 10% are familial.

29:22

But that's, that's an old number.

29:24

I don't think that's actually accurate.

29:26

I think, um, many more genetic associations are

29:29

now being, um, now being discovered, and they

29:33

often present with symptoms related to excess

29:36

catecholamine production of hypertension or arrhythmia.

29:40

So, um, just as a segue into von Hippel, um, so von

29:45

Hippel syndrome is associated with an increased incidence

29:48

of pheochromocytoma, about 10 to 20% of patients.

29:51

Um, in 50% of those cases, they're bilateral cases, and

29:54

they do have a high incidence of metachronous lesions

29:58

that are identified after, um, after surgical removal

30:01

of one lesion, that, uh, one will occur in another site.

30:05

Um, 20% of them are extra-adrenal.

30:09

Uh, the, uh, the malignancy or the neoplasm that's

30:13

of, um, more concern, I think, in the setting of

30:16

von Hippel–Lindau is a, um, source of morbidity and

30:19

mortality is renal cell carcinoma, so about 28 to 45%

30:22

of patients with VHL develop renal cell carcinoma.

30:26

And these typically present in younger patients than

30:29

the typical age of onset for renal cell carcinoma.

30:32

But that being said, it's still older than

30:34

the pediatric population, so it's still

30:36

unusual that, um, that this would present

30:38

with RCC in, uh, in a pediatric patient.

30:42

Renal cysts are exceedingly common in von Hippel–Lindau,

30:44

so it's up to 75% of patients.

30:47

Pancreatic hepatic cysts are also associated with

30:49

VHL, but adrenal cysts have not been really reported.

30:53

Um, and then pancreatic neuroendocrine tumors

30:56

are another association with von Hippel–Lindau.

31:00

So from imaging, uh, on ultrasound, uh, pheochromocytoma

31:04

typically is a round or ovoid soft tissue mass.

31:07

It's fairly variable, the echogenicity of it.

31:10

Um, on CT, one, um, notable thing to remember is that

31:14

there's, uh, typically avid contrast enhancement.

31:17

Um, one of the, uh, the classic teachings,

31:22

um, was that, uh, you wouldn't want to give, um,

31:27

you wouldn't want to give, uh, iodinated contrast to these

31:30

patients because of the risk of a hypertensive crisis.

31:32

But, um, nowadays, uh, we give nonionic iodinated

31:36

contrast to patients.

31:38

And so the risk of any hypertensive crisis is

31:41

not really any greater than in any other patient.

31:45

Um, these typically can be heterogeneous

31:48

due to cystic or necrotic components.

31:50

They may have, uh, internal hemorrhage, or rarely,

31:53

they may have areas of calcification.

31:57

This is an example on MR. Um, so just a picture from

32:00

the internet, but I'll show you another, uh, a case

32:03

on the next slide, um, of pheochromocytoma and MR.

32:07

Um, the hallmark features, as I mentioned.

32:10

Um.

32:11

You know, that term light-bulb bright.

32:13

Uh, and that's, uh, reflecting on their

32:15

appearance on T2 of pheochromocytoma.

32:18

But this is only seen in about 70% of patients.

32:20

Um, on CT there's, uh, you know, similarly on MR,

32:24

there's avid enhancement unless there happens to be some

32:27

areas of cystic or, uh, cyst development or necrosis.

32:33

And then this is just an example of a bilateral

32:36

pheochromocytoma in a patient with von Hippel–Lindau.

32:40

And so you can see here that this is a T2-weighted image,

32:44

and it doesn't really have that light-bulb bright appearance.

32:46

There's a cystic internal component, um, or

32:50

necrotic internal component, which you can see

32:52

on this post-contrast image is not enhancing.

32:54

So it, it doesn't quite fit the rules, um, the, uh,

32:59

the light-bulb bright appearance, but as I mentioned

33:01

before, about 30% of them don't really fit that rule.

33:07

So this is a 17-year-old male with left upper quadrant pain.

33:13

And so you can see here on the image on the left, there's

33:18

the heterogeneous, uh, T2-hyperintense suprarenal mass.

33:22

Uh, you can see that it's generally hyperenhancing,

33:24

but there are some hyperenhancing foci.

33:27

So if this patient was, um, about

33:30

15 years younger, I think we would

33:33

guess that this is most likely neuroblastoma.

33:36

Um, but this patient's quite a bit older than that, and

33:39

so neuroblastoma is not really typical in this age group.

33:42

So another thing to consider is other neural crest tumors.

33:45

So in this case, this is a ganglioneuroma.

33:47

Um, these can be incidentally detected,

33:50

but they may present with mass effect.

33:52

Um, and then rarely they may have enough catecholamine

33:55

secretion to cause flushing or hypertensive syndromes.

33:58

Um, it may be difficult to distinguish these on an

34:02

imaging basis from non-metastatic neuroblastoma.

34:05

Um, and as I mentioned, the median age

34:07

for ganglioneuroma or other neural crest

34:09

tumors is typically older than for neuroblastoma.

34:11

Um.

34:13

So just briefly going over some of the imaging

34:16

features that you'd expect for, uh, ganglioneuroma.

34:19

Um, on ultrasound, they typically are, um, homogeneous.

34:24

They're hypoechoic, well circumscribed. On CT,

34:27

they tend to be homogeneous, which is in contrast, though, to,

34:31

um, to, um, neuroblastoma, which tends to be a little bit

34:36

more heterogeneous because of the development of necrosis.

34:39

Um, on MR, they tend to be low on T1

34:42

and heterogeneously high on T2, and they

34:44

tend to have fairly variable enhancement.

34:46

Um, one important thing to note is that because

34:48

of the catecholamine production, um, they can

34:51

also be MIBG avid, similar to neuroblastoma.

34:53

So that really doesn't necessarily, um, give you a

34:56

differentiating, um, factor between the two of them.

35:01

All right, and this is the sixth case.

35:03

This is a newborn with a left upper

35:05

quadrant lesion that was noted prenatally.

35:08

Uh, on our CT, though, you can see that

35:10

this lesion is actually, uh, has a notable

35:14

appearance of an arterial feeding vessel.

35:17

And this, even though it looks like a, um, an adrenal

35:22

region mass, it's actually a subdiaphragmatic,

35:26

uh, extralobar pulmonary sequestration.

35:29

So pulmonary sequestration can mimic a, uh,

35:33

an adrenal mass if it's subdiaphragmatic.

35:36

Um, pulmonary sequestration, in general, can

35:39

be supradiaphragmatic or subdiaphragmatic.

35:41

Um, if they are subdiaphragmatic, they

35:43

tend to be the extralobar type.

35:45

And remember the distinction between the two of

35:47

them is the extralobar, the intralobar types, is

35:51

whether or not there's systemic venous drainage,

35:53

which occurs in extralobar types, or pulmonary

35:56

venous drainage, which occurs in intralobar types.

36:01

So on imaging, pulmonary sequestration, uh,

36:03

tends to show as an echogenic focal mass. You

36:05

may appreciate the anomalous arterial supply.

36:08

Um, more work has been done recently in, um, in

36:12

the last, uh, 10 or so years, um, fetal imaging.

36:16

And so these can be appreciated, uh, prenatally as

36:19

well, and the feeding vessels may be appreciated there.

36:22

On CT or MR, uh, you can generally

36:24

better localize the anomalous vasculature.

36:26

Um, and from a surgical planning standpoint, it's,

36:31

uh, important to recognize the anomalous artery.

36:33

The venous drainage really shouldn't make a difference

36:35

in terms of, um, the approach for the repair, but the artery

36:38

is the feeding vessel that's really the important thing to find.

36:41

Um.

36:43

As a protocoling, uh, tip in general, um, you would,

36:47

if you have any suspicion that there's a pulmonary

36:49

sequestration, you'd want to do CT angiography.

36:51

If there's any suspicion, in general, that you have

36:53

a neonatal lung lesion that is, um, that you'd

36:57

like to get a CT for, typically it should be a CTA.

37:01

Um, that being said, if it's subdiaphragmatic sequestration,

37:04

where you're thinking about possibly an adrenal

37:06

mass, um, it may be hard to know this prospectively.

37:11

This is, uh, our seventh case. It is a

37:13

15-year-old with acute-onset abdominal pain.

37:18

And so, um, superior to the right kidney,

37:20

you see kind of this heterogeneous, ugly-looking

37:23

mass, uh, which has, um, it's predominantly

37:26

hypoechoic, but there's definitely some

37:28

hypoechoic areas that, um, look like necrosis.

37:31

And there's definitely some pronounced

37:34

vascularity within this region.

37:37

So a CT was done to better characterize.

37:39

And you can see here that, uh, in addition to this mass,

37:43

which is fairly heterogeneous and has large areas of

37:46

necrosis, there's a satellite mass within the liver.

37:50

There's multiple pulmonary masses as well.

37:54

Um, so this is an example of a

37:56

metastatic adrenal cortical carcinoma.

37:58

Rare, um, it arises from the adrenal cortex.

38:02

Um, there is a bimodal, um,

38:04

involvement.

38:05

So under the age of five, um, but typically older than

38:09

neuroblastoma is one peak, and the other peak is in

38:12

patients ages, uh, in the 30- to 40-, 50-year-old range.

38:17

Um, histologically, these tumors are not exactly

38:19

the same, even though they both fall under

38:21

the umbrella of, um, adrenal cortical carcinoma.

38:24

Pediatric patients typically present

38:26

with, um, endocrine symptoms.

38:28

Uh, these are often very large at presentation.

38:30

There's a few, um,

38:32

genetic syndromes with an increased risk of, uh,

38:35

adrenal cortical carcinoma, including Beckwith–

38:38

Wiedemann syndrome and familial adenomatous polyposis.

38:44

So more commonly, um, these are located on the right,

38:47

for whatever reason, but, uh, up to 15% of them are bilateral.

38:51

And then frequent sites of metastasis include,

38:53

uh, lungs, liver, skin, and lymph nodes.

38:58

So on ultrasound, um,

39:01

adrenal cortical carcinoma tends to be small.

39:03

Um, if it's small, um, it's homogeneous.

39:07

But most of them, as I mentioned, are,

39:10

uh, present when they're fairly large.

39:12

And in those cases, they tend to be heterogeneous,

39:14

um, because of the areas of necrosis.

39:16

Um, and then they have intermixed

39:17

areas of color flow, uh, on CT.

39:21

Um.

39:22

They're typically heterogeneously enhancing.

39:24

They can displace or even invade adjacent organs just

39:28

'cause of the na, the aggressive nature of this lesion.

39:30

Um, you can use CT for characterizing metastatic disease

39:34

and 25% of 'em have central calcifications on MR.

39:38

Um, you know, as with many of the lesions that we've

39:40

uh, talked about, they're sort of T1 heterogeneous.

39:43

They tend to be T1, T2

39:45

bright, but they are variable.

39:46

And then there's heterogeneous enhancement

39:48

related to the, uh, degree of necrosis.

39:51

I think this may be our last case, but it's a

39:54

newborn female who's presented with some virilization.

40:00

So these are the adrenal glands, and you know that from

40:04

the trilaminar appearance, they can see cortex medulla.

40:08

Cortex.

40:09

And so what you can appreciate here is that these sort

40:13

of have a much more bulky appearance and that it's not

40:16

really that inverted Y, but there's a lot more tissue.

40:18

And that's really the case for both sides.

40:21

Probably more so even on the left that it

40:23

has, um, that really bulky, um, appearance.

40:28

And this is an example of congenital adrenal hyperplasia.

40:32

Um, it's really a group of conditions, but.

40:36

All with the same endpoint, which is that

40:38

there's diminished cortisol production, and 90%

40:41

of 'em are due to, uh, 21-hydroxylase deficiency.

40:44

So these inadequate cortisol levels cause

40:48

pituitary to stimulate ACTH production, and

40:51

then that causes stimulation of the glands.

40:53

And so you get this really bulky appearance of the

40:56

adrenal glands, but generally normal morphology.

40:59

But of, of.

41:00

Of the, um, tissue differentiation, but

41:03

just very, very bulky, as you can see here.

41:06

So it may be difficult to clinically suspect these

41:09

in males, but in, um, females, clitoromegaly or

41:13

enlargement of labial folds are typically noted.

41:17

So on ultrasound, um, the enlarged adrenal

41:20

glands can be appreciated bilaterally.

41:23

Um, it may be tough to appreciate this in newborns, but, um.

41:27

In general, just because the adrenal

41:28

glands tend to be very pronounced anyway.

41:31

But the classic description, um, is

41:34

this cerebriform appearance, or this

41:36

brain-like appearance of the adrenal glands.

41:38

And if you think to areas of, um,

41:42

what you'd expect to see on neonatal.

41:45

Um, uh, what you'd expect to see on, uh, neonatal

41:49

brain sonography, that this sort of has that appearance

41:51

of the sulcal fold pattern, the gyral pattern,

41:56

and then the intermixed, um, tissue in between.

42:00

And so that's where that concept of

42:02

the cerebriform appearance comes.

42:04

Um, some of the other features include

42:06

a stippled appearance of the gland and

42:08

asymmetric, uh, enlargement on the left side.

42:11

So as in this case where the left is

42:13

more, uh, pronounced than the right side.

42:18

So it's an important diagnosis to make.

42:20

Um, you know, not from, uh, from an imaging

42:22

standpoint, it can be challenging, but, um, it's.

42:25

The clinician really, uh, doesn't want to miss this to

42:28

avoid, um, the possibility of salt-wasting crisis.

42:31

And then, um, just in terms of gender development,

42:34

too, uh, important for the, um, for the sake

42:36

of appropriately assigning a patient's sex.

42:39

Um, these are typically treated medically.

42:42

So I think that's a, uh, general overview of some of the

42:46

more common pediatric adrenal lesions that you'll encounter.

42:49

Um, remember with neuroblastoma.

42:52

Um, there's still some evolution in the staging and, um,

42:56

and there's been a transition to an image-defined risk

43:00

factor-based staging system where, um, emphasis is

43:05

on the imaging appearance, uh, prior to surgery rather

43:10

than the old staging system, which is post-surgically.

43:13

Um, remember adrenal cortical carcinoma is fairly rare.

43:18

Um.

43:19

When thinking about neuroblastoma as a, um, as an adrenal

43:26

lesion, um, ganglioneuroma and ganglioneuroblastoma

43:30

are other of those neural crest tumors that can be

43:32

considered or, and are typically in older population.

43:36

Um, just recapping some of the other cases

43:39

that we had, remember with, um, hypertension.

43:42

Um.

43:43

You can think about things like pheochromocytoma,

43:46

um, because of its catecholamine production.

43:49

And pheochromocytoma is typically seen, uh, is

43:53

in, um, in the older pediatric patients if you

43:56

are going to see it in the pediatric population.

43:59

And, uh, some of the syndromes associated with the

44:01

one that we discussed in depth was, um, was, uh.

44:09

Von Hippel–Lindau syndrome, um, which is notable for, uh,

44:13

adrenal cortical carcinoma and for pheochromocytoma,

44:15

as well as for renal cell carcinoma.

44:17

Um, and remember with neonatal adrenal hemorrhage,

44:21

one of the take-homes that I wanted you to, uh,

44:23

remember is that these typically, uh, will, uh,

44:27

resolve with time, but they should be followed with

44:30

ultrasound just to exclude the possibility of cystic,

44:33

um, neuroblastoma or some sort of congenital neuroblastoma.

44:39

All right, and that's the end of my presentation,

44:43

and I'm happy to take any questions.

44:47

So I've got a couple questions.

44:48

Um,

44:52

one is regarding 18F-DOPA imaging in neuroblastoma,

44:56

and I haven't actually encountered any 18, uh,

44:59

F-DOPA imaging in the study of neuroblastoma.

45:04

All right.

45:05

And there's a, um, a follow-up question, uh, from another

45:14

attendee regarding, uh, staging of neuroblastoma cases.

45:18

So typically image-defined risk factors are something

45:20

that we should, uh, consider putting in our reports.

45:24

You should have some familiarity with it.

45:25

I do.

45:26

I, you know, I, I don't think it's

45:28

necessarily in the scope to know, um,

45:31

to know them by heart.

45:32

But I think it is helpful when, uh, for

45:35

initial staging to refer to, um, to refer

45:39

to the imaging image-defined risk factors.

45:41

And that, um, that publication I put at the end of my

45:43

presentation is a, um, is a, uh, is a good reference.

45:49

Um, and it does feature that chart, which

45:51

I was initially shown, I think, in 2011.

45:54

Um, but the staging regarding, um,

45:59

uh, regarding neuroblastoma,

46:03

uh, there's another question on the incidence

46:06

of adrenal adenoma and adrenomyelolipoma,

46:09

um, in children and how to diagnose them.

46:12

So adrenal adenomas are pretty uncommon, um, in children.

46:16

I think one of the things that you'd really

46:17

want to look for is, um, using chemical shift,

46:21

and trying to identify them on the in- and

46:23

out-of-phase, but it's pretty uncommon that

46:25

the children present with adrenal adenoma.

46:27

I think you're much more, um, I would say that in

46:30

general that should be much lower on your differential

46:33

when considering adrenal lesions in pediatric patients.

46:36

Um.

46:37

Adrenomyelolipoma, again, is exceedingly

46:39

uncommon, uh, in pediatric patients.

46:42

Um, I, I, I really would not think of them

46:45

very high on the, your differential diagnosis.

46:47

And just as a, as an aside, um, you know, when thinking

46:50

about fatty lesions or things like, you know, adeno, I

46:53

think, um, a helpful thing to do when imaging is, um,

46:57

to, uh, use axial, uh, GRE sequences.

47:03

So use, um, things like in Siemens, use the, um, the VIBE

47:06

sequences, and GE use the LAVA images, um, where they use

47:11

a Dixon technique, and you can, um, in addition to getting

47:14

your GRE images, you can also get, uh, in- and out-of-phase

47:17

images so that you're getting more bang for your buck.

47:24

Okay.

47:26

Um, and then somebody's, uh, uh, offered,

47:29

another attendee offered a question regarding

47:31

how Hirschsprung's is related to adrenal.

47:33

And so, uh, you know, I just wanted to emphasize it's

47:35

not really that it's related to the adrenal gland, it's

47:38

just that, um, the bulk of stool is presenting as a left

47:43

suprarenal mass, and so it's important to think about that one.

47:46

Thinking about, um, you know, an imaging

47:48

area that can be very challenging, uh,

47:50

sometimes to identify what's in the suprarenal space.

47:54

Um, and in that case that we had, um, the, uh,

47:59

the suprarenal, uh, region, there was stool filling

48:03

that area, which made it look on ultrasound as

48:06

though there was an actual mass in that area.

48:12

Okay.

48:13

I think I've addressed, uh, all these questions.

48:18

Um, I am, thank you guys for attending,

48:21

and I hope you guys found this helpful.

48:27

All right, guys, uh, as we bring this to a close,

48:30

I want to thank you, Dr. Shet, for your time today.

48:32

And thanks to all you guys for

48:33

participating in our noon conference.

48:35

A quick reminder that this conference will be

48:36

available on demand on, um, mrionline.com,

48:41

in addition to all the previous noon conferences.

48:43

Tomorrow we're going to be joined by Dr. Ellen Chung for

48:46

a lecture on creating an environment of stability.

48:48

You can register for that at mrionline.com and

48:52

follow us on social media at The MRI Online for

48:54

updates and reminders on upcoming conferences.

48:57

Thank you guys again so much, and have a great day.