0:01

So next is, we need to know what is the

0:03

ideal protocol to evaluate pancreas.

0:05

So nowadays we are talking about abbreviated

0:08

MR protocols because we need lesser table time

0:11

that is more efficient for the departments.

0:13

And a comprehensive protocol actually deals with

0:16

coronal T2-weighted images, axial T2-weighted

0:18

images, and then fat-suppressed T2-weighted and

0:21

diffusion-weighted with ADC, in-phase and out

0:23

phase T1, and fat-suppressed T1-weighted images.

0:27

In addition to that, we need post-contrast

0:29

images if we are dealing with the pancreas.

0:31

Tumor specifically, and that is taken

0:33

at 15 seconds and 35 seconds, and it is

0:36

very important to understand because

0:38

this timing is different than the liver is.

0:40

Liver receives the supply from,

0:42

mostly from portal vein, pancreas receives

0:44

mostly from the aorta, directly from the

0:46

aorta, which comes from the celiac trunk.

0:49

So it enhances earlier than the liver is.

0:51

And the lesions, those are hypointense,

0:53

are better seen on the arterial phase,

0:55

and the venous phase is important to

0:57

delineate the anatomy and relationship.

0:59

with the different structures and the vascularity.

1:02

And in addition to that, we can add

1:03

coronal T2 and 3D MRCP sequences.

1:06

Taking post-contrast T1 coronal is

1:09

optional, but some of the institutions

1:11

do that to make it more comprehensive.

1:13

But again, in my opinion, they can,

1:15

that can increase the time of scanning.

1:17

For the abbreviated protocol, mostly people are

1:19

dealing with the cystic lesions in the pancreas.

1:22

And we are just trying to follow up

1:23

different cystic lesions like IPMNs.

1:25

And that can be very, very short,

1:27

just taking coronal T2, axial T2 with and

1:30

without fat separation, and MRCP images.

1:32

And that should be sufficient to

1:34

measure the lesion and follow this up.

1:37

On T1-weighted images, the pancreas

1:38

demonstrates high intensity compared

1:40

to the liver and the musculature.

1:42

And that happens because of the high content

1:44

of the protein, paramagnetic substances like

1:46

manganese, or higher content of the endoplasmic

1:49

reticulum within the pancreatic cells.

1:51

On fat-suppressed T1-weighted images,

1:53

pancreas even becomes more hyperintense.

1:55

That happens because of the dynamic

1:57

range increases on the background.

1:59

And that is actually good for us

2:00

because we can find the lesions as

2:03

hypointense even on pre-contrast images.

2:05

You can actually demonstrate whether the

2:07

lesion is situated and how it is related with

2:09

the mesentery and other overlying structures.

2:12

On T2-weighted images, the pancreas looks

2:14

slightly hyperintense or intermediate

2:16

compared to the musculature or the liver.

2:18

And we can actually find

2:19

cystic lesions really well.

2:21

on the background of T2-weighted images.

2:23

As I said earlier, arterial phase is taken about

2:25

15 seconds, and, uh, venous phase is taken about

2:28

35 to 45 seconds, uh, just to be very precise.

2:32

And this is how the pancreas looks.

2:34

We can see on T2-weighted images here,

2:37

we can delineate the pancreatic duct.

2:39

This is the CBD, and we can see the intensity

2:43

of the pancreas as compared to the musculature

2:45

slightly hyperintense or intermediate.

2:47

And this is how we can see the

2:49

entire pancreas up to the tail.

2:51

On T1-weighted fat-suppressed pre-contrast

2:53

images, you can see that parenchyma are looking

2:55

slightly hyperintense compared to the background.

2:57

That happens because of the dynamic range

2:59

increases on the background throughout.

3:01

And if something is, like,

3:02

hyperintense, this is actually an SMV here.

3:04

But if you have a hyperintense lesion,

3:06

you can see it better on this background.

3:08

And you can delineate a relationship with the SMV

3:10

or any other structures in the mesenteric root.

3:13

This is a quick idea how we can see the entire

3:15

abdomen on T2-weighted coronal weighted images.

3:18

You can see the entire abdomen,

3:20

including all of the structures: spleen,

3:21

liver, kidneys, if there is any other

3:24

pathology in the abdomen, adrenal gland.

3:27

And then we can start seeing the

3:28

pancreatic tail from the splenic hilum.

3:31

And we can follow this up

3:36

forward and see the pancreatic anatomy

3:40

throughout with the pancreatic duct

3:42

and its insertion with the CBD.

3:45

So coronary tubated images are very,

3:47

very important because sometimes you can

3:48

catch some of the pelvic pathologies.

3:50

And those are better seen only on

3:52

these images because otherwise you're

3:54

going to miss those pathologies.

3:56

And these are the MRCP images where you can

3:58

see the entire pancreatic duct draining into

4:00

the major papilla and the CBD draining along

4:03

with the pancreatic duct in the major papilla.

4:06

Just to give you a quick idea about secretin

4:08

MRCP, these are very important because if

4:10

you want to pick up a pathology which is

4:11

subtle enough and you cannot see otherwise,

4:14

you can give secretin to the patient.

4:16

And take images afterwards.

4:17

It's a very unique protocol.

4:18

Basically what we do, we take a thick slice,

4:21

thick slab T2-weighted projection sequences,

4:23

and pick up a slice where we can see the entire

4:25

pancreatic duct, as well as CBD together.

4:28

And in the background, we have negative

4:31

T2-weighted contrast, which can be anything.

4:33

I mean, some of the people actually use manganese-

4:35

containing liquids like pineapple juice.

4:38

And if you give that titrated negative

4:41

oral contrast to the patient, it's going

4:42

to suppress the abdominal content throughout.

4:44

And then we inject about 1 cc per 10 kg

4:48

secretin IV and take images about 15 to 30 seconds

4:51

for about next 10 to 15 minutes.

4:54

And then we just see the side

4:57

ducts or the main pancreatic duct

4:59

better after giving secretin.