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Hello everyone and welcome to Noon Conferences

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hosted by MRI Online. In response to

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changes happening around the world

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5 00:00:07,260 --> 00:00:09,180 right now and the shutting down of in-person

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events, we decided to provide free

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conferences to all radiologists worldwide.

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Today we're joined for a lecture from Dr. Nataliia Dichko

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on the role of radiologists in liver transplantation.

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Dr. Dichko received her medical degree and

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completed a residency in diagnostic radiology

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at the National Medical University and further

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education at the Faculty of the National Medical

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Academy of Postgraduate Education in Kyiv, Ukraine.

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And constable Ukraine in the ESR Education Committee.

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A reminder, there will be a Q and A session at

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the end of the lecture, so please use the

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Q and A feature to ask your questions, and we'll

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get to as many as we can before our time is up.

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That being said, thank you all

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so much for joining us today.

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I'll let Dr. Dichko take things from here.

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Thank you for the kind introduction, warm

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greetings to all of you dear colleagues.

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And before I start, I would like

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to say thank you to organizers.

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I'm really glad to be present here as a part of

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this educational platform, and today we'll discuss

1:05

the role of radiologist in liver transplantation.

1:09

I have nothing to disclose, and we will have the next

1:13

plan of our lecture and start our talk from the

1:16

basic knowledge about transplantation itself.

1:20

Then we will discuss a list of

1:21

indications and contraindications.

1:24

And then we will move on to the main and

1:27

the most interesting part of our lecture.

1:30

We will see what kind of protocols we have.

1:32

We will discuss parenchymal evaluation and

1:35

possible incidental findings, tips and tricks

1:39

of liver volumetry, vascular

1:42

evaluation, and biliary tract at the end.

1:45

So transplantation is a treatment of choice for

1:48

the patient with an end-stage of liver disease.

1:51

What is the main step for recipient is to be included

1:55

in national waiting list and when the suitable

1:58

donor is found, both of them, they receive medical

2:03

evaluation, including laboratory and clinical

2:07

tests, and then, of course, radiologic evaluation.

2:11

And in this point,

2:13

the radiologist enters the game.

2:15

What is important to mention here is that

2:18

radiologists should be included in transplant team.

2:22

Then further, based on the results of diagnostic

2:27

imaging, they together plan surgery itself,

2:32

and then patient will have a surgery and go to

2:36

the rehabilitation phase and further follow-up.

2:41

And here is a simple evaluation

2:44

protocol for potential living

2:45

liver donors.

2:47

Radiologists play one of the key roles in this

2:50

scenario and rapidly developing imaging technologies

2:54

give us an opportunity to demonstrate the role

2:56

of state-of-the-art imaging in the operative planning.

3:00

Focus on the main clinical tasks: successful

3:03

surgery for both donor and recipient,

3:06

especially where it is a living donor.

3:11

And here's our part.

3:13

A considerably healthy donor receives upper

3:17

abdominal CT scan and further volume of

3:20

the liver and, uh, vessel angiography.

3:25

And furthermore, maybe invasive or special

3:31

investigations such as MRI of liver for

3:35

additional liver evaluation and biliary system.

3:41

Depending on the type of a donor, there are

3:43

two types of transplantation that exist and are named:

3:47

Deceased donor liver transplantation and living

3:51

donor liver transplantation. For

3:54

example, in our clinic for the previous year,

3:57

there were performed almost 200 liver

4:00

transplantations, and the biggest amount of

4:03

them was living donor liver transplantation.

4:07

And what is also important to mention is that

4:09

close relatives for a recipient are priority,

4:14

and of course they should be complementary

4:16

by all laboratory and radiological features.

4:21

Going forward, what is the indication list?

4:24

And it includes, for the first, acute liver failure,

4:29

which occurs according to the inflammation process.

4:33

For example, hepatitis, autoimmune

4:36

hepatitis, drug toxicity.

4:39

For example, then we're going

4:41

to the next point: cirrhosis.

4:44

Chronic liver diseases.

4:46

In the case of autoimmune hepatitis,

4:49

maybe alcohol liver disease, and

4:53

other point is metabolic liver disease.

4:56

In this case, it could be end stages of cirrhosis,

5:01

iron overload, or hemochromatosis, Wilson’s

5:04

disease, cystic fibrosis, et cetera.

5:08

Also in this list are included biliary

5:11

diseases, for example, biliary

5:13

atresia is right here.

5:15

S. Sclerosis con, primary biliary cirrhosis.

5:20

Also here, some vascular diseases, of course, in the

5:24

first place Budd–Chiari syndrome or occlusive disease.

5:29

And also in this list included primary liver

5:33

malignancy, hepatocellular cancer, carcinoid tumor,

5:37

epithelioid hemangioma, and the other reasons.

5:42

For example, polycystic liver disease,

5:47

or maybe severe trauma or traumatic injury of liver.

5:53

Well, let's take a look.

5:54

There's a list of contraindications

5:56

to liver transplantation surgery.

5:59

They are divided into absolute and relative.

6:02

There's a list of absolute contraindications.

6:06

Extrahepatic malignancy or metastatic

6:08

disease included. Active, uh, uncontrolled

6:12

infections, for example, an ongoing

6:14

pneumonia or fungal infection or sepsis.

6:18

Then, uh, patients with a brain death, for

6:22

example, in the case of severe traumatic

6:25

injury, will be unfortunately excluded from

6:28

the waiting list for the liver transplantation.

6:32

Uh, some syndromes, uh, anatomy abnormalities

6:36

that preclude liver transplantation.

6:39

Also, unfortunately, patients with

6:42

Acquired Immunodeficiency Syndrome is here.

6:46

Um, then ongoing alcohol or substance abuse.

6:51

There is a preparation program that exists where

6:54

mentioned as a rule for recipient time

6:57

point at six months pre-operation without

7:01

alcohol or forbidden substances abuse.

7:05

And the last is, uh, severe cardiopulmonary disease.

7:10

To relate to this list,

7:13

considerations could be attributed: HBV

7:17

infection, advanced age of recipient, cholangiocarcinoma,

7:21

and psychological instability.

7:26

The patient, the gold standard for donor imaging

7:30

is contrast-enhanced CT with further volume and

7:35

post-processing of angiography, and of course, MR.

7:39

MR with MRCP.

7:42

And additional sequences if it's gonna be necessary.

7:46

For example, a liver lab, sometimes in some cases

7:49

may be supplemented with ultrasound or contrast-

7:54

enhanced ultrasound examination of the patient.

7:57

But we use as usual CT and with

8:00

a combination with MR imaging.

8:04

So let's take a look at our CT protocol.

8:07

The recommended slice thickness for post-processing—

8:11

the best is one millimeter. Then imaging phases.

8:16

Non-contrast CT scan is used to detect liver steatosis

8:20

or calcium deposition in the parenchyma.

8:24

Then a single slice arterial angiographic scan

8:27

with volume rendering

8:31

and maximum intensity projection reconstruction

8:34

demonstrates vessel anatomy, also including even

8:37

small segmental hepatic arteries, its variants and

8:42

pathology. For example, small RHA could be occurred

8:47

and found with this post-processing evaluation.

8:52

Late arterial and venous phase allow for

8:56

characterization by hyper- or hypovascular

9:00

focal liver lesion and venous anatomy.

9:03

Delayed phase is optional, but delayed phase

9:06

facilitates the characterization of liver suspicious

9:12

lesions. For example, small cholangiocarcinoma

9:16

and fibrotic lesions or tissue.

9:20

However, I would like to mention that contrast

9:23

agent concentration would be not less than

9:27

350 milligrams iodine per milliliter for a

9:31

dose of 1.5 till 2.5 milliliters per kilogram

9:37

body weight of patient and injection rate three, but

9:40

the better is of course five milliliters per second.

9:45

Anyway, CT protocols and phases should

9:49

be carefully optimized to reduce the

9:53

radiation dose for the living liver

9:57

donor during screening

9:59

procedure. It's very important.

10:01

Going forward, MRI protocol. We have both scanners,

10:06

MRI scanner with, um, MR field 1.5 Tesla

10:12

or 3.0 Tesla, phase array multichannel coil.

10:18

If it's necessary, we inject

10:20

hepatobiliary contrast and it's preferred.

10:23

Imaging phases almost the same as in CT: arterial

10:28

phase, portal, delayed or transitional phase,

10:32

hepatobiliary phase, T2-weighted, MRCP,

10:37

coronal, oblique plane, and exhale imaging.

10:41

They are optional.

10:42

3D respiratory

10:45

gated sequences are preferred here, and additional

10:50

sequences is a liver lab, which includes IDEAL IQ, Dixon

10:55

with a selected ROI and its calculated fat signal

10:59

fraction and R2*, R2* mapping and iron deposition.

11:06

Moving forward, what kind of incidental finding

11:10

could be found during parenchymal evaluation?

11:13

The most often and frequent is steatosis or hepatic

11:18

steatosis. Steatosis refers to an increase

11:21

of intracellular fat in the liver.

11:24

This diffuse change

11:27

affects nearly 25% of the population.

11:31

But there are three types of steatosis

11:35

that exist: focal hepatic steatosis, most

11:38

often diffuse hepatic steatosis, and multifocal

11:42

nodular hepatic steatosis, which is rare.

11:46

But, uh, diffuse hepatic steatosis can lead to fibrosis

11:50

in the end stage and, as a result, uh, liver cirrhosis.

11:55

Here is an example.

11:57

Uh, CT unenhanced.

11:59

You may combine this.

12:01

Two parenchymal organs, liver and

12:03

spleen, and the liver attenuation would

12:06

be lower than the combined spleen.

12:09

And after contrast injection, the focal fatty

12:13

sparing is here. You may see in this example.

12:17

And, uh, liver is, uh, uh,

12:21

heterogeneous geographic regions.

12:25

The liver in a peripheral,

12:28

um, space of, uh, right lobe.

12:32

As you can see there.

12:35

So parenchymal evaluation also includes liver

12:39

fibrosis as a reason, as a common feature of almost

12:43

all causes of chronic liver disease. It involves the

12:47

accumulation of collagen and other macromolecules.

12:52

Macromolecules within the extracellular

12:54

matrix. Fibrosis itself tends to progress,

12:58

leading to hepatic dysfunction,

13:01

portal hypertension, and ultimately cirrhosis.

13:06

The current clinical standard for reference

13:10

for assessing liver fibrosis is a biopsy,

13:13

but we want to exclude all this manipulation,

13:17

and, uh, we may show and use our tools.

13:21

For example, MRI elastography and a fabulous detailed

13:25

lecture less than months prior was near channel by

13:31

Dr. Javadi, and he told every tip

13:35

and trick about the elastography.

13:38

I will just briefly touch that.

13:40

The protocol includes in and out of

13:43

phase sequences, Dixon sequences,

13:47

T2 single-shot TIR, NAvFat saturation,

13:52

R2* and T2* relaxometry

13:55

for iron identification. As you can see in this

13:59

example, confidence maps will be generated.

14:04

Then going next, it's iron deposition or, as called,

14:09

hemochromatosis. It's a metabolic disorder with

14:14

abnormal and overload iron accumulation,

14:18

and increasing of total body iron stores.

14:21

Liver, as we know, is a primary

14:23

organ of deposition and also the

14:28

choice is a biopsy of the liver, but we try to

14:32

avoid, as I told, and MR is the method of choice,

14:36

non-invasive measuring and management of patients

14:40

with primary to secondary hemochromatosis.

14:43

And here is an example of this screening MR

14:48

liver iron quantification, which includes T2*

14:51

relaxometry with different echo times as needed,

14:55

and signal intensity ratio

14:58

performed using ROI, different ROIs.

15:02

And you may see in this example patient with, uh,

15:05

iron overload liver in these images.

15:11

Then LiverLab is, um, additional sequences.

15:16

It's a semi-automatic software, comprises

15:19

the fat and iron screen component.

15:22

Two-point and two methods for evaluation:

15:27

Multi-Dixon VIBE,

15:29

six-point Q-Dixon and image-based method and histo-

15:34

path-based method, spectroscopy with using spectroscopy.

15:39

It also provides clinical reports, and here

15:42

are some examples of this software calculation.

15:46

Non-invasively identification,

15:49

with Q-Dixon automatic liver segmentation and

15:53

report, estimate liver volume and number

15:57

of voxels, and reports the

16:00

presence of the intrahepatic fat.

16:03

And here is an example of Q-Dixon

16:06

automatic liver segmentation.

16:09

And, uh, ROI Q-Dixon report histograms.

16:14

They describe proton density,

16:16

fat fraction values, and R2*

16:18

values distribution, as you may see here.

16:23

And, um,

16:25

also, Q-Dixon reports color bars show the

16:30

values of proton density fat fraction and R2*,

16:34

both for the whole liver volume

16:37

segment and for the ROI positioned in the right

16:41

lobe, as it is marked just right here.

16:44

You may see on this example.

16:46

Here's another one,

16:48

example of the patient.

16:49

Also the same color bar shows the values

16:53

of the fat fraction and table with report.

16:58

Uh, here in this patient it's, uh, 50% of fat signal

17:02

fraction, which is a sign of, um, liver steatosis.

17:09

So going forward, what else could be in the par-

17:14

enchymal evaluation is vascular disorders such as

17:18

Budd–Chiari syndrome or hepatic venous outflow obstruction.

17:23

This term is applied to the clinical manifestations

17:27

of hepatic venous outflow obstruction at

17:30

any level from the small hepatic veins to the

17:33

junction of the inferior vena cava and the right

17:37

atrium, regardless of the cause of obstruction.

17:41

When it's acute, uh, situation,

17:43

there are clinical, uh, symptoms.

17:46

Occur, but when it's chronic, it could

17:49

be an incidental finding of a patient, and

17:51

chronic appear in the case of vessels, uh,

17:55

perivascular fibrosis related to inflammation.

17:59

And here you may see another example of

18:02

early enhancement of the caudate lobe and central liver

18:07

around the inferior vena cava, inhomogeneous molded

18:11

liver, hepatomegaly, and, uh, regenerative nodules.

18:17

Then we are going forward. Hemangioma.

18:21

It's a benign finding very often,

18:25

and it's, uh, just a simple liver

18:27

venous malformation. As usual,

18:30

it's incidental, and it could be

18:32

multiple or a single small finding.

18:37

It depends, but it's not—as usual—

18:39

it's not preclude, uh, donation of a liver.

18:43

It depends on the size and also the

18:46

location. You should discuss it together

18:49

with the surgeon, and of course, you should

18:52

carefully report all these findings in your, uh,

18:56

diagnostic report to the recipient and donor.

19:01

Parenchymal evaluation includes, uh,

19:04

other incidental finding is hepatic

19:07

adenoma. It's also benign,

19:10

solitary tumor, generally hormone-induced.

19:14

It could be also, if it is small,

19:17

asymptomatic, and could be incidentally found.

19:20

Clinical investigations occur when it's

19:24

hemorrhage or rupture occurs in this lesion,

19:29

when it can be a bigger size, or a hemorrhage

19:34

could occur even in a small adenoma.

19:37

Also, you should carefully report it and, uh, show all

19:43

these findings in your report.

19:47

Then focal nodular hyperplasia, benign liver lesion.

19:51

Also, it could be asymptomatic small

19:55

lesions and strong female predilection.

19:58

Sometimes it's also hormone-induced and,

20:01

as usual, an incidental finding, and

20:04

has the special sign—a central scar.

20:08

But, uh, the small, uh, small, um,

20:12

um,

20:13

small lesion could not preclude donation,

20:17

and sometimes patient, uh, need further

20:21

investigation or diagnostic imaging.

20:26

Unfortunately, not only benign incidental

20:29

findings could occur. Sometimes small,

20:33

um, small aggressive lesion could be

20:36

found during the screen. And one of the

20:39

most common is hepatocellular carcinoma.

20:42

The most common malignant primary liver tumor

20:45

is strongly associated with liver cirrhosis.

20:49

And this tumor plays in the fifth place

20:52

of the most common cancers in the world.

20:55

And here is an example of asymptomatic small, uh,

21:01

tumor, which is located in the left, uh, liver lobe.

21:05

Here is in different phases of, um, enhanced CT.

21:10

And here is an example also of a small,

21:13

uh, hepatocellular carcinoma,

21:15

during MRI

21:17

visualization, also as an incidental finding.

21:22

Another type of finding is, uh, cyst. So

21:27

you should differentiate it from a simple

21:29

cyst, because, um, a simple cyst should not

21:32

include any septae or calcium deposition.

21:36

And this occurs in the case of hepatic hydatid disease.

21:41

It's serious, and also patients need, uh, some special

21:47

treatment in the case or maybe any other examination.

21:52

It could be

21:53

not so easy to perform liver transplantation,

21:59

and it also could be a contraindication

22:03

to liver donation—this incidental finding.

22:08

So going to the liver volumetry itself, it's

22:12

very important to discuss it previously with a

22:15

surgeon, what type of transplantation is gonna

22:18

be. And in case when it's adult recipient, the

22:22

left lobe or right lobe totally can be needed.

22:26

But if it is children and less than 10

22:30

kilograms of body weight, sometimes their

22:34

only left lateral section is necessary to be donated.

22:39

You should discuss it together with the surgeon.

22:42

And we're going, um, exactly to

22:45

liver volumetry to perform.

22:48

In our clinic, we use a semi-automatic software,

22:52

and you may see how it looks in this window.

22:56

It's, um,

22:57

a few windows with special marks with a type of, um,

23:05

vessel visualization for a portal vein, for example,

23:08

angiogram, hepatic vein, about liver itself.

23:14

If there are any incidental findings, you may

23:17

put some special, uh, phase just right here.

23:21

And if you have

23:23

MR or MRCP in the right, uh, lower corner,

23:28

you should put these images. Going to the selection

23:33

of all these types of images, you are gonna see

23:36

the next picture. Here, I try to select

23:41

the best variant. It's gonna be, um, liver

23:45

um,

23:46

visualization.

23:47

The best is a portal phase, as I remember.

23:51

Yeah.

23:52

And here is, um, a, uh, portal

23:55

phase also marked, uh, hepatic veins.

23:59

In this example, we haven't got any incidental

24:02

lesions, so there is absent here any, um, uh,

24:07

picture and we haven't got

24:10

any immersive visualization.

24:12

We just were working with, um, uh,

24:15

enhanced, uh, computed tomography.

24:18

Then the next step is, um,

24:21

phase registration.

24:23

Sometimes you should check, uh, if, uh, everything

24:26

is correct or if you, uh, need, uh, some, um,

24:33

markers you could manually just correct, uh, phase

24:37

or organ location by itself in this window with, uh,

24:42

phase registration.

24:45

Then going to the next step, which

24:48

is gonna be, uh, liver segmentation

24:51

itself, and it's performed automatically.

24:54

All liver volume, as you may see

24:56

here, it's marked with a blue color.

24:59

All liver parenchyma automatically marked.

25:02

But if it's necessary, uh,

25:05

to perform some corrections,

25:08

because, uh, some major vessels or

25:11

nearby organs could be included,

25:14

you should use this toolbar and manually correct

25:19

any, any changes if you

25:22

need, if you decide that, um,

25:25

it's necessary. And slide by slide,

25:28

check all this liver volume. And if you

25:33

agree, your mark is accepted, and, uh, it'll

25:37

automatically calculate all liver parenchyma volume.

25:41

Then going to the next step is vessel

25:44

segmentation. Here is marked, uh, um, type of a

25:49

vessel with which you're working just right now.

25:53

It's hepatic vein, and you choose, um, previously with

25:57

a phase selection, um, portal or hepatic vein phase,

26:03

where these types of vessels are better marked.

26:07

And you work with, um,

26:10

uh, some

26:12

manually markers. Uh, you should—you

26:17

should manually mark a vessel, and then

26:21

automatically all hepatic veins can

26:24

reconstruct during the post-processing.

26:27

And you also

26:28

need to check up if everything is correct.

26:32

If it's not, you should, uh, just manually change

26:37

your marker and, uh, reload, for example,

26:41

and, uh, renew—just renew all

26:44

your, um, vessel segmentation.

26:49

And the same situation with the portal vein.

26:51

You may see here now you are working with a portal

26:54

vein, and here it is. It's bright, and I guess

26:58

it's gonna be a good automatic segmentation

27:02

of these vessels after your manual marking.

27:05

And the same situation with

27:07

um, uh, hepatic angiography.

27:10

Uh, here it is marked that you are

27:13

working with arterial phase, and here

27:15

is, um, hepatic artery bright and, um,

27:19

marked right here.

27:21

Then the next step after finishing

27:26

all these vessel segmentation is, um,

27:30

liver virtual planning—liver resection

27:33

virtual planning itself—and you should

27:37

perform it together with the surgeon,

27:40

'cause you discuss the lines of resection

27:43

together and, depending on the middle hepatic

27:47

vein including or excluding it, so you come

27:52

together and decide what type of resection is gonna

27:56

be, and you draw manually all lines which are

28:00

necessary for this virtual operation planning.

28:06

And, uh, here is a toolbar for, um,

28:10

drawing, and then it automatically

28:13

performs, uh, the resection as planned.

28:17

Or if it's necessary, some segmental resection, you

28:21

may mark as a segment resection of a partial liver.

28:27

And, uh, at the end it’s gonna look like that, marked

28:31

with different colors: right lobe and the left

28:34

lobe, and automatically it calculates

28:38

all, uh, volumes which are necessary

28:42

depending on right or left liver lobe.

28:46

And here it’s gonna look in the final

28:49

report, showing possible graft

28:53

volumes. You may see in this example.

28:56

And here it looks like, uh, what is

28:59

gonna be—uh, exactly right

29:02

lobe marked with a different

29:04

color—and the left lobe.

29:06

Here it is all examples of volumes, and then

29:12

you calculate, uh, as necessary for

29:18

the recipient. This volumetric calculation should be

29:22

performed together with a surgeon to exclude and to

29:26

prevent small-for-size syndrome and correlation

29:31

with territories and, um, their blood supply.

29:37

Sometimes it could be needed when, um, some, uh, not

29:41

typical resection is planned or, for example, just

29:45

a lateral left lobe resection.

29:49

Also, um, different, uh, segments

29:53

with different volumes, and it also

29:56

calculates automatically by using this.

30:01

Software.

30:03

So moving forward, a recipient requires a

30:07

graft of, uh, 0.8% of his body weight ratio

30:13

to avoid the small-for-size syndrome. With a

30:16

normal liver parenchyma, a liver treatment

30:19

volume of 30 or 40% of the total liver volume

30:24

is considered adequate for a donor's survival.

30:29

And, uh, as I know, a minimum 30% future liver for

30:34

normal healthy livers is standard in the United States.

30:39

And, uh, more conservative volume, or more

30:43

than 35% for older patients may be considered.

30:49

And in our report, we should mention

30:51

the future liver and 19% by using these

30:57

formulas. And, uh, for recipient, we

31:01

calculate graft-to-recipient ratio, and it's

31:04

really important, uh, to report it, uh, in our, um,

31:11

radiology, uh, radiology report for the surgeon.

31:17

Then going to vascular evaluation, uh, we'll

31:22

start from a three-dimensional volume rendered

31:26

image shows a normal hepatic arterial anatomy.

31:30

And here is an example, uh, when the

31:33

classical anatomy is shown.

31:35

Then the common hepatic artery

31:37

arises from the celiac trunk.

31:40

You may see it here. Then,

31:42

now, left gastric artery is going just right.

31:45

Here is also typical gastroduodenal artery

31:50

and proper hepatic artery, and then this

31:54

proper hepatic artery dividing distally

31:57

into the right and the left branches.

32:01

But this classic and standard anatomy is not, um,

32:07

so often, and, um, different variation could occur.

32:14

And, uh, it's very important

32:16

to mention them in, uh,

32:19

our radiological report. And Professor Michel

32:23

has classified the anatomic variants of the hepatic

32:27

artery into 10 subtypes, as it's shown here in

32:31

the table. And the most often is, uh, type III,

32:36

where the right hepatic artery arises

32:39

from the superior mesenteric artery.

32:41

This type of, uh, anatomical variant is

32:45

most frequent, and we should mention

32:48

it just to minimize risk to the recipient.

32:52

Because, uh, single vascular anastomoses

32:55

are preferred, and accessory hepatic arteries

32:59

pose an increased risk of complication or

33:03

bleeding or ischemic complication.

33:07

We should mark it and show it to our surgeon.

33:11

It's really, really important and necessary.

33:15

Then going to the portal venous anatomy.

33:19

Portal venous variants appear in

33:21

approximately 10% of cases.

33:24

In, uh, this example shows

33:26

the classic variant of anatomy.

33:28

Where is the main trunk? Then going, uh, left...

33:32

Um...

33:34

Left, uh, portal vein branch, and the right, uh,

33:37

posterior and anterior segments of, uh, portal vein.

33:43

And here is an example.

33:44

There are five major variants in the portal

33:47

venous anatomy shown here in this table.

33:51

But, uh, type B, portal vein trifurcation, is

33:56

the most frequent one, and, um, personally

34:01

I saw it the most often in my patients.

34:05

And, uh, what is important is that the right-sided

34:09

variation may preclude right donation. And,

34:13

uh, also all variants we should mention

34:15

in our report and show everything to the

34:20

surgeon. Also, what is important to mention is that if a

34:24

portal vein variant is observed, you should be really

34:29

careful reviewing biliary anatomy because,

34:34

uh, sometimes—no, not sometimes—even often,

34:38

almost always—they are the same.

34:41

'Cause if we have, uh...

34:43

For example, uh, type B portal vein trifurcation,

34:47

it is really high percent that their biliary

34:51

tree is gonna be the same with the trifurcation,

34:54

and you should, uh, observe it carefully.

34:59

So going to the hepatic venous anatomy,

35:02

and here is the classic variant.

35:04

Where is a middle hepatic vein, right hepatic

35:07

vein, and the left hepatic vein is present.

35:11

But, uh, any known hepatic venous variants

35:16

could preclude donation. And, uh, it's

35:19

important to ensure sufficient outflow

35:22

drainage for right lobe liver donation.

35:27

And you should carefully

35:29

investigate all, all hepatic veins.

35:32

'Cause, uh, really very often, uh, we should, um, uh,

35:38

look for, um, accessory right inferior hepatic vein.

35:43

And, uh, this is the most common variation

35:46

of, uh, hepatic vein anatomy variant.

35:50

And it is present in up to almost 50% of the

35:55

population and drains the posterior part of the right

35:59

lobe directly into the inferior vena cava, as it shows

36:04

just right here in this example. Here are different

36:07

types of, uh, accessory right inferior hepatic vein.

36:12

An accessory right inferior hepatic

36:14

vein can help to drain liver segments.

36:16

Segments that remain following B segmentectomy,

36:21

seven and eight, for example.

36:23

And here is my patient with, uh, accessory

36:27

right hepatic vein segment, and it marked here.

36:32

But it wasn't only one.

36:34

It was two large accessory inferior right hepatic

36:38

veins in this patient, like it was showed previously.

36:42

In the example, it could be not only one, it

36:46

could be multiple accessory hepatic veins.

36:51

Moving to the main hepatic venous anatomy

36:54

as the key of the right lobe donation.

36:56

We should mention that during right-sided

37:00

hepatectomy, one or more significant branches of the

37:04

main hepatic vein will need to be transected.

37:07

And here is an example of

37:09

different anatomy variations

37:12

mentioned right here, and reconstruction

37:15

of the middle hepatic vein is necessary

37:19

if the transection plane contains significant segment V

37:23

V5 segment or V8 segment variant veins, or

37:28

even their combination, which also should be

37:32

reported and shown to our surgeon. But sometimes

37:37

different, uh, abnormal or unusual atypical

37:42

types of resections should be performed.

37:46

And it's really important to mention

37:49

variant anatomy of the right hepatic

37:52

vein, as it's shown just right here.

37:56

This example, or left hepatic vein, like

38:00

it's shown on the right example and table.

38:03

And this also should be described

38:06

and shown to our surgeon.

38:09

And moving to the last, but not the least, is the

38:12

biliary tract. The classic biliary anatomy is shown

38:17

here, and preoperative knowledge of intrahepatic bile

38:21

duct anatomy is crucial for

38:24

planning liver transplantation.

38:26

The first and the main aim of MRCP

38:29

is to assess the biliary tree anatomy

38:32

and possible variants.

38:34

Here is an example of 3D MRCP with a classical

38:39

biliary tract tree anatomy. And, uh, not always

38:45

it's like that.

38:46

There exist a few variants

38:49

and they're shown just right here.

38:51

There biliary variants identified at MR

38:56

cholangiography include drainage of the right

38:59

posterior duct into the left duct or common

39:03

hepatic duct and trifurcation patterns.

39:06

Could require additional anastomosis

39:10

if left lobe donation is planned.

39:13

And here is an example of a right-sided

39:19

branch called crossover.

39:22

An anomaly here is marked like here is

39:26

type IIIA, and also type of trifurcation.

39:31

As I said before, a statistically

39:34

significant association between portal venous

39:37

and biliary variants was also demonstrated

39:41

by Professor Lee and colleagues.

39:43

As I told you previously, if we have a portal

39:47

trifurcation assessment in portal venous

39:52

anatomy, so it's really high opportunity there

39:56

there's gonna be a biliary

39:58

trifurcation in this patient.

40:01

And, um, it's also

40:04

really important to mark in your report, and

40:08

other types and variants of

40:14

biliary tract anatomy are shown just here on this table.

40:18

And they are important to recognize

40:21

if a left hepatectomy is planned.

40:23

Here they are—the most complicated

40:27

ones—for different, um,

40:31

segments, as it’s marked just right here.

40:35

So to conclude, I would like to say

40:38

that radiologists play a vital role in

40:42

ensuring the safety of living liver

40:46

donation by handling powerful diagnostic

40:48

tools such as MR, MDCT, and MRI.

40:54

But, uh, unfortunately, however, there

40:57

is no standard algorithms

41:01

for imaging or reporting that exist.

41:05

And, uh, I would like to mention that, um, our

41:09

take-home message gonna be like that:

41:11

That for successful transplantation and

41:14

minimizing risks for the donor, the best

41:17

choice for us is teamwork with the surgeon.

41:21

Then a combination of all available

41:23

methods could help us exclude contraindication

41:26

or incidental findings

41:30

which may preclude donation. Then the correct

41:33

MR and MDCT protocols are valuable tools in the

41:38

evaluation of potential living liver donors that

41:42

provide complete and comprehensive information

41:46

on the hepatic vascular anatomy, the liver

41:49

parenchyma, and the volumetric measurement.

41:53

At this point, I would like to

41:55

thank you for the attention.

41:56

I hope my message was interesting, and I

42:00

will be happy to answer all your questions.

42:05

Thank you.

42:08

And I can see a few questions right here.

42:11

Uh, first, according to, um, um...

42:15

Liver scintigraphy.

42:16

Any comment about use, um, liver scintigraphy for

42:21

measurement of hepatic functional, uh, reserve?

42:24

Um, in, uh, to be honest, uh, in our clinic we

42:28

don't use, uh, nuclear imaging techniques.

42:32

Um, they are great and useful to visualize

42:37

acute and/or biliary, um, bowel obstruction

42:43

or some, some surgical bowel leak.

42:46

They are great, but, uh, I guess we are

42:49

going from the simple, um, techniques

42:54

to the, um, complicated some, but we use...

42:57

Ultrasound is a primary modality for initially

43:01

assessing suspected biliary pathology, and, um...

43:05

Ultrasound is available everywhere, is fast method.

43:10

It requires minimal, uh, patient preparation.

43:14

Uh, and what is important, it avoids ionizing radiation

43:18

in case of, uh, dose-reducing examination.

43:21

So, uh, we don't use, um, unfortunately...

43:26

Uh, these methods in, in our, uh...

43:29

Um, preparation of, uh, donors.

43:33

Uh, then the next question is about superior

43:37

mesenteric artery origin of hepatic artery

43:42

variation, uh, via gastroduodenal or

43:46

main, uh, superior mesenteric artery.

43:50

Um, if I got it clear, um...

43:53

Um, the question according to, uh, more

43:58

complicated, um, anatomic variant, uh, I guess...

44:02

But in my practice, I saw, um, the biggest

44:07

amount of, uh, variations, uh, of hepatic

44:11

artery with the superior mesenteric artery.

44:14

Um, less frequent...

44:17

Only once or twice, uh, we, uh,

44:20

with, uh, gastroduodenal artery.

44:23

And, uh, if it's gonna be easier or more

44:26

complicated to, uh, perform, uh...

44:29

Surgically, um, anastomosis, it's an answer...

44:34

Uh, or answering, gonna be from the surgeons.

44:38

'Cause, uh, I, I saw just, uh, uh, some vessels,

44:42

some variations, and I report them.

44:45

And, uh, all other decisions about, um...

44:49

Which variant is gonna be better and,

44:52

uh, in the future, um, uh, to the

44:55

patient is the decision of the surgeon.

44:58

So, um, I guess, I, I hope

45:02

that I answered this question.

45:05

Uh, then another chat is about, um...

45:09

Um, about, um, post-transplantation

45:12

complications. Um, it's an examination,

45:16

then post-surgical of a patient.

45:19

And, um, the most frequent one

45:22

is, um, um, biliary, um, with...

45:28

Organizing hematoma. But, uh, it's not, uh...

45:33

Often. In my practice with our patients, uh...

45:37

I didn't, uh, see them as a complication. Also,

45:42

uh, sometimes, uh, hepatic thrombosis occurs.

45:47

Uh, it's a more often complication,

45:49

and, um, it depends on...

45:51

Uh, different, uh, parameters, uh, also

45:56

include in the laboratory changes. 'Cause, um...

46:00

Liver transplantation is also not a technical

46:03

situation—situation of immune response of a patient.

46:07

And sometimes, uh, different hemodynamic changes

46:12

occur and, uh, thrombosis or ischemia...

46:16

And as a result, ischemic changes of...

46:18

Parenchyma could occur. But, uh, it's not also

46:23

often—just, it was once or twice in my practice.

46:27

Um, what else?

46:28

Uh, um, some bleeding...

46:31

Bleeding.

46:31

It's according to anastomosis changes. But,

46:35

um, I have never seen that in my practice.

46:41

'Cause, um, all technical situations and technical...

46:46

Changes, uh, which could occur...

46:49

It was, it was not, um, in, in my

46:53

experience, uh, with my patients.

46:57

Um, then, um, what is the main

47:00

items in the template report?

47:03

Thank you.

47:03

Main items.

47:04

Um, so, of course, uh, main, uh, positions

47:08

and main points where you should...

47:09

Top is, uh, liver volumetric.

47:13

Um, the, the first question from the surgeons

47:15

you're gonna have is, uh, what the volumetric...

47:18

Um, liver active and functional liver volume.

47:24

And, uh, according to, uh, um, different

47:28

parts of transplantation—if it's gonna be

47:31

left lobe donation or right lobe donation—

47:35

it depends, uh, to avoid, um...

47:38

Uh, small graft syndrome.

47:40

They need to know, um, volume of,

47:44

uh, transplanted, uh, graft.

47:46

Um, and we calculate in our

47:49

report, we calculate, as I showed, uh,

47:52

Graft-to-recipient ratio. It’s a number,

47:58

uh, of, uh, parameters of weight and

48:02

height of patient and volume of liver,

48:05

as you saw it in, um, in my lecture.

48:09

Then we, the second question gonna be about the

48:12

vessels, of course, uh, 'cause, uh, it depends,

48:15

uh, how complicated surgery gonna be and

48:20

some unexpected, uh, um, situations gonna occur.

48:23

Bleeding or, or something.

48:26

They should know everything about arteries and, um,

48:31

Um, main hepatic vein. Main hepatic vein, uh,

48:34

plays a key role according to, um, um, liver

48:38

resection to the right or left, uh, lobe donation.

48:43

And, uh, we are carefully, uh, explore what

48:48

kind of branches, uh, to the different segments

48:51

of, uh, from the main hepatic vein are going.

48:54

And, um,

48:56

biliary anatomy, of course.

48:58

Um, but it depends.

48:59

It's almost, um, the same as, um,

49:04

portal venous anatomy.

49:05

It is interesting 'cause they are almost,

49:08

uh, as, um, the same going and, and it's also

49:13

important to, to mention. And, um, also if any,

49:19

uh, incidental findings gonna, gonna be there.

49:21

Of course you report it.

49:22

But, um, in this case it's gonna be even

49:26

question about excluding from the liver donation.

49:29

Uh, it depends on, uh, which finding you're gonna,

49:32

which findings you're gonna have, uh, from this, um,

49:36

uh, liver donor.

49:38

So if, uh, it is healthy donor, then, uh, these

49:41

points, uh, as I told you previously, um, liver

49:45

volumetric and, uh, the vessels and, um, biliary

49:49

anatomy, these points are the main, and, uh,

49:53

you should, uh, absolutely mention all that.

49:56

And, um, that's—

49:58

So that's maybe some additional questions

50:00

gonna be from your surgeon team. But, um,

50:04

we, we report on just, just like that.

50:07

Uh, so, um, success of liver transplant?

50:11

839 00:50:12,675 --> 00:50:16,365 No, we discussed too it like, uh, complications.

50:16

Uh, it is a further evaluation of a patient,

50:20

um, with success of liver transplant.

50:23

It's great when we can, uh, see them and follow

50:27

up after year or two after transplantation and,

50:32

um, success depends on, um, teamwork, I guess.

50:36

Surgeon, radiologist,

50:38

and all, all, uh, teamwork, uh, in your clinic.

50:42

Um, so I guess that's, that's all.

50:45

That's all questions.

50:46

Uh, if I missed something, um, maybe,

50:51

um, I guess I answered all, all the

50:54

questions which I can see in the, our chat.

50:58

Um, so I hope you liked my lecture and this

51:02

information was interesting for all of you.

51:06

If there are any questions, I'm gonna be glad to answer.

51:10

Right, everybody?

51:10

Yes.

51:11

Producer close.

51:11

I wanna thank Dr. Dichko for this lecture and thanks to

51:14

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51:16

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51:18

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51:20

in addition to all the previous new conferences.

51:23

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51:25

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51:27

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51:30

normal variants, and pitfalls.

51:32

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51:34

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51:36

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51:39

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51:42

Thank you so much.

51:43

Thank you.

51:43

Bye.