0:01

So this is another case where we have a question

0:03

whether it is a mass, cancer, or pancreatitis.

0:07

And as we see here, the CBD is dilated, and lots

0:11

of intrahepatic bile ducts are also dilated.

0:14

And as we follow this downwards,

0:16

we see change in the caliber of the CBD,

0:19

which becomes slightly narrow suddenly.

0:22

And then we see a lesion in the pancreatic head,

0:26

which is kind of slightly intermediate signal

0:28

intensity compared to the parenchymal

0:31

intensity in the rest of the pancreas.

0:34

But the good thing here to note is that we see

0:37

non-dilated duct, with some of the side branches

0:40

dilated, which just shows abrupt cut off at

0:44

the location of the anticipated apparent mass.

0:48

So can we have a mass like this,

0:50

where there is no ductal dilatation?

0:52

Yes, that can happen.

0:53

Sometimes it is possible that you have a mass which

0:56

has not chronically evolved; it was very aggressive

0:58

enough that it evolved in few days and few

1:01

weeks, and it never allowed time for dilation

1:03

to the duct to dilate and undergo

1:06

atrophy in the pancreas; that can happen.

1:08

But the point here is, in this particular

1:10

mass, the lesion is all confined within the

1:15

periphery or the outline of the pancreas itself.

1:18

We see the vessels in the neighborhood.

1:21

Those are looking mostly clean except

1:23

some haziness or fat stranding, which

1:25

can happen in any kind of inflammation.

1:28

None of the vessels are compromised

1:30

in caliber, at least on T2.

1:31

Okay.

1:32

And we do not see any other findings

1:34

like adenopathy or mesenteric deposits.

1:38

And we do not see anything in the liver.

1:40

So point is, what kind of pancreatitis

1:43

it can be, if it is pancreatitis.

1:44

It doesn't look like it is chronic pancreatitis.

1:46

But it can be autoimmune pancreatitis.

1:47

And as I said earlier, we can be the first person

1:52

calling autoimmune pancreatitis because the serum

1:54

levels are negative, specifically in type 2.

1:58

And focal masses can present.

1:59

Mostly in the pancreatic head.

2:00

But it can present anywhere.

2:02

So in this case, given this appearance,

2:07

the first impression in my mind was it

2:09

is possibly autoimmune pancreatitis.

2:11

So what I did, I moved to the DWI here,

2:15

and as we go to high B value DWI, I do

2:18

not see significant change of intensity

2:21

compared to the rest of the parenchyma.

2:24

So it is possible that autoimmune

2:26

pancreatitis can show diffusion

2:28

restriction, and it is still pancreatitis.

2:31

And it can mimic adenocarcinoma.

2:33

But once you don't see it, once it is

2:35

absent, that is more reassuring that it

2:38

is possibly not adenocarcinoma at least.

2:41

So not seeing diffusion restriction was

2:42

a very good sign, at least in this case.

2:45

And as we go to the ADC, we do not see significant

2:47

difference in attenuation or intensity here

2:50

compared to the rest of the parenchyma.

2:52

And once we go to the arterial phase,

2:55

let's see how it looks on pre-contrast first.

2:58

Because if the tumor is there or chronic

3:00

pancreatitis is there, it should be

3:01

fibrotic and it should appear hypotense,

3:04

compared to the rest of the parenchyma.

3:06

In our case, it appears close to ISO or slightly

3:11

hypertense to the rest of the parenchyma.

3:13

Can this still be pancreatitis?

3:15

Because yes, it can be because if you have

3:17

higher content or edema inside the pancreas,

3:20

edema will have more water content,

3:23

and it'll look slightly more hypertense on

3:25

T1 weighted images, more water, more high point.

3:30

So let's see how it looks on arterial phase.

3:32

Remember, in the arterial phase, fibrosis

3:34

will look high, pointent.

3:36

And it will be seen better.

3:38

But what happens in this case,

3:40

that apparent mass actually enhanced

3:42

as the rest of the parenchyma did.

3:45

It was not hypointense.

3:46

So now we have three things together.

3:49

A duct which is not dilated, parenchyma which

3:51

is maintained, apparent mass in the pancreatic

3:53

head which enhances in the arterial phase,

3:57

it is homogeneously enhancing, it is well

3:58

defined, it is not encasing along with the

4:01

vessels and doesn't show diffusion restriction.

4:05

And let's see how it looks on delayed phase.

4:10

Again, we can see the legion is mostly

4:12

confined to the boundaries of the pancreas

4:16

and it is not invading any of the vessels.

4:19

All of the vessels are spared.

4:20

Remember, cancer will always cause

4:22

some kind of abatement or encasement

4:24

because it has aggressiveness,

4:28

which pancreatitis doesn't have that.

4:30

Pancreatitis is usually benign, so it

4:32

doesn't have that, that aggressiveness.

4:34

It can lead to involvement of

4:36

the fat in the surrounding.

4:37

It can lead to It can lead to dirtiness,

4:40

but it will never involve a vessel.

4:43

Inflammation can cause dirtiness in the fat,

4:46

but it will never involve the surrounding vessels.

4:49

And as we go to the delayed phase, we see

4:52

the similar kind of finding, homogeneous

4:54

diffuse enhancement of the pancreatic

4:56

head lesion with maintained boundaries

5:00

without involvement of the vessels.

5:02

So, given this appearance, we strongly

5:05

came to the conclusion that what we

5:06

are seeing is not a case of cancer.

5:08

It is most likely autoimmune pancreatitis.

5:11

And then we advised follow-up

5:13

after the steroid has been given.

5:16

So what we did, we followed up on this

5:17

case and see what happens here.

5:21

This is a follow-up in the

5:22

same case; that mass is gone.

5:26

There is nothing there.

5:27

The pancreas looks just absolutely normal.

5:30

And in this case, serum and

5:32

IgG4 were negative.

5:34

So this was actually a type 2A IP autoimmune

5:38

pancreatitis, and see the ductal dilatation in the

5:42

CBD and intrahepatic bile duct is also resolved.

5:45

So that means whatever we had.

5:47

The involvement of the terminal CBD was because of

5:50

that inflammation going on in the pancreatic head.

5:52

So all the strictures dilatation has been resolved

5:55

after the treatment was given to this patient.

5:58

And that mass is no longer existing there.

6:00

And we can see the same finding on the

6:03

post-contrast homogeneous enhancement

6:05

of the pancreas without any apparent

6:07

mass, completely resolved pancreatic

6:09

dilatation and CBD is also looking normal.

6:13

So this was a proven case of autoimmune

6:15

pancreatitis, which was diagnosed exclusively on

6:18

the MR. And we saved an unnecessary VAPL procedure,

6:23

which is a very extensive procedure, and which

6:25

can cause compromised pancreatic parenchyma,

6:28

and can lead to type 2 diabetes, unnecessarily

6:31

in a patient who has just had pancreatitis.

6:34

So your diagnosis, an accurate, precise

6:37

diagnosis on MR, can save lives, and can prevent

6:41

unnecessary procedures like VAPL procedure.