0:02

Hello, and welcome to Noon Conference hosted by MRI Online.

0:06

In response to the changes happening around

0:08

the world right now and the shutting down of

0:10

in-person events, we have decided to provide free

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noon conferences to all radiologists worldwide.

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Today we are joined by Dr. Kimi Kondo.

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Dr. Kondo is an associate professor of

0:21

radiology, division of Interventional Radiology

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at the University of Colorado.

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She is board-certified in interventional

0:31

radiology and diagnostic radiology, and a fellow

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of the Society of Interventional Radiology.

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A reminder that there will be a Q&A session

0:40

at the end of the lecture, so please use the Q&A

0:42

feature to ask your questions, and we will get

0:44

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

0:47

That being said, thank you all

0:48

for joining us today, Dr. Kondo.

0:50

I will let you take it from here.

0:52

Well, welcome everybody, and thank you for joining me.

0:55

Today I'm going to be talking about renal cryoablation.

0:59

And in terms of the learning objectives, I hope at

1:02

the conclusion of this presentation that you're going to

1:06

be able to describe the methods by which cryoablation

1:09

functions, summarize the benefits and risks of

1:13

percutaneous cryoablation for renal tumors, and be

1:16

able to discuss the indications and contraindications

1:20

of percutaneous cryoablation for tumors.

1:23

And just note, I don't have any, um, relevant

1:27

financial disclosures.

1:30

In terms of cryoablation, we first

1:32

have to talk about how this works.

1:34

Um, as you can see right here, these are the probes, and you

1:40

can see the formation of ice, and how that works is basically

1:46

the Joule–Thomson effect, where the probe itself is hollow.

1:50

And as you can see that at very high

1:53

pressure, um, we have gases that go through.

1:57

So if we have argon.

2:00

Then it comes out, and it's going to return.

2:03

That's going to be kind of a low-pressurized system.

2:07

And so basically when you have that occurring, you

2:11

have rapid expansion of this gas, resulting in the

2:15

change of temperature, and with argon that

2:18

results in cooling or the formation of an ice ball.

2:22

And then if we wanted to warm the probe back up,

2:25

we would be using and pushing helium through.

2:28

So you'll both have argon and helium tanks

2:31

set up and connected to the cryo machine.

2:36

The probes themselves are anywhere from 13 to 17 gauge, and

2:41

at the edge of the ice ball, it's going to be zero degrees.

2:45

So you're going to see that visible ice.

2:48

But we don't consider that to be kind of what I

2:51

consider a killing temperature, and so we always want

2:55

to have at least five millimeters of an ablation margin.

2:59

And that's, you know, I, when I talk to patients,

3:02

I tell them that it's the same with surgery.

3:05

You can never see, you know, like micros

3:08

or at the microscopic level, little cells.

3:11

So you always want to have that surgical margin.

3:14

And I think, you know, patients understand what that is.

3:17

And for the same reason, we're going to have kind of that

3:20

ablation margin where, yes, we're going to, uh, be

3:25

treating or, or injuring normal tissue,

3:29

but that's because of this margin.

3:32

In terms of how cryoablation works, it works

3:36

by both direct and indirect cellular injury.

3:39

When you have the freezing, what happens

3:41

is that extracellular ice will form first,

3:45

which will decrease the amount of extra-

3:48

cellular free water and increase that osmolarity.

3:52

So the water is going to go from inside the cell to

3:56

outside the cell, causing cell shrinkage and dehydration.

4:00

When the intracellular ice forms, then

4:04

you've got damage to the cell membrane.

4:06

And then additionally, any of the vasculature,

4:09

you're going to have intravascular ice form

4:12

within the blood vessels when you thaw.

4:15

And typically when we do this, you're going to have two cycles.

4:19

You're going to have a freeze cycle,

4:21

then a passive thaw, a second freeze

4:24

cycle, and then an active thaw.

4:27

In order to get your probes out during that

4:30

passive thaw, you're going to have melting of

4:33

that extracellular ice before the intracellular

4:37

ice, which is going to drive water into the cell,

4:41

which, in addition to having the, the ice and the

4:46

swelling from that, by driving the water in, you're

4:49

going to have further, uh, bursting of the cells.

4:53

And then again, you'll have endothelial damage

4:57

to the blood vessels because, again, it'll draw

4:59

water out of those cells because of edema.

5:02

And I like to tell patients, and I think a way that they

5:05

can easily understand this, is if you tell them, um, about,

5:10

say if you have a full bottle of, of water in

5:14

those, you know, really thin plastic containers,

5:18

and if you put it in the freezer, what happens?

5:21

Well, typically it expands and it bursts.

5:24

And so that's the same thing, um,

5:27

with what happens to the cell.

5:28

And they can visualize that and,

5:31

and understand that concept.

5:34

There's also delayed, um, damage.

5:37

And basically, um, one, you have the ischemia that occurs

5:42

from, so that you don't get, uh, in terms of the healing,

5:47

you have apoptosis, and then you'll have the macrophages and

5:50

the neutrophils, you know, kind of clean up all that debris.

5:54

So the other thing that's really important,

5:56

and I think most patients are going to ask, is

5:58

like, okay, you know, is this going to be.

6:02

A lot of times they think of these types of procedures

6:06

like surgery, where tissue is going to be removed, but remind

6:09

them that, no, with ablation, it's not going to be removed.

6:13

But what will happen is that it'll scar down and get smaller.

6:18

In terms of the probes, um, there are basically two systems.

6:23

One is Galil, which was bought by Boston Scientific, and so

6:28

for those, um, IceSeed, IceRod, IceSphere, and they have

6:33

different sizes in terms of gauge, as you can see here.

6:37

And then what these isotherm, um, pictures show you is

6:41

the shape of the ice ball itself and what is considered

6:46

zero ice versus negative 20 degrees,

6:48

negative 40.

6:50

And what we want to achieve in renal tumors

6:54

is at least the negative 20-degree ice.

6:57

Um, if you are talking about something like

6:59

prostate, then you're going to want that negative 40.

7:03

But in renal tumors, negative 20 is just fine.

7:07

But as you can see, there's a pretty significant, uh,

7:11

you know, width of that zero-degrees ice.

7:14

So you really have to make your, the size of your ice

7:16

ball and your ablation zone bigger than the tumor itself.

7:21

The other, uh, product is Endocare, which was

7:25

initially sold and bought by HealthTronics, and

7:28

then that division was recently bought by Varian.

7:33

And so similarly, they have a different right-angle

7:38

probes.

7:39

They also have a variable right-angle probe,

7:43

which you can have a 1.5-centimeter setting

7:47

all the way up to a five-centimeter setting.

7:50

This is really nice because you can see

7:52

that the shape of the ice ball is a little

7:55

bit less of an egg, and some of these, uh,

8:00

uh, sizes, and typically, most of the time, the active

8:06

tip is going to be three centimeters in size, but with

8:09

this variable probe, you can change that, that distance.

8:14

The only downside of using this probe

8:17

is that it even, um, because it's a slider and it's a

8:21

right angle, is that it is longer than the other probes.

8:25

And so you really have to make sure that,

8:28

depending on the patient's body habitus, that

8:30

you've got clearance in the scanner gantry.

8:35

So what are the advantages and

8:38

disadvantages of cryoablation?

8:40

Well, one, the ice ball is visible with CT, and so

8:44

whether or not you place the probes with CT guidance

8:48

or ultrasound guidance, um, typically we're going

8:52

to be watching the size of the ice ball with CT.

8:57

I know that initially at the beginning

9:00

of cryoablation, a lot of, uh,

9:03

intraoperative or say maybe laparoscopic ultrasound was

9:08

being done by the urologist, but the problem was is that

9:13

they could never see the, the backside of the ice ball.

9:17

And so that resulted in a number of

9:21

residual RCC from incomplete treatment.

9:25

And so, like I said, whether or not you place the probes

9:29

with ultrasound or CT, you want to monitor that size with CT.

9:34

Um, the other thing that I've found as opposed to

9:37

other methods of ablation, namely heat-based, which

9:41

would be RFA, radiofrequency ablation, or microwave,

9:46

is that typically I find that patients have less pain

9:50

during the treatment because you're also going to have

9:53

cooling of the nerves that are within the tissues.

9:57

And so most of the time I'm able to

9:59

do this with conscious sedation and,

10:01

quite honestly, more patients complain of if they're in

10:06

a prone position of maybe having their arms over their

10:09

head as opposed to having pain at where I'm treating.

10:14

You can use up to eight probes independently.

10:18

Um, into one machine.

10:20

So that's certainly an advantage, and I find that

10:26

that cold, as opposed to a heat-based ablation system,

10:31

tends to be less harmful to the collecting system.

10:34

They actually did an animal model where

10:36

they punctured the collecting system with,

10:40

um, the probe and didn't have any leaks. Now,

10:44

granted saying that there have certainly been,

10:47

uh, reports and, uh, experiences where even

10:52

with cryoablation that you've had a urine leak.

10:56

The same with RFA and with microwave ablation.

11:00

But I find that typically I can get away with having

11:04

the probe a lot closer, especially with the more

11:08

central tumors with, uh, cold rather than heat.

11:12

It's an outpatient procedure.

11:14

Um, if, for example, the patient has pain or there's

11:19

some complication, you can keep them overnight, but

11:22

I would say 98% of my patients go home the same day.

11:27

One of the disadvantages of using cold is that you have

11:30

an increased risk of bleeding because you don't have the

11:33

cautery effect that you would have with a heat-based system.

11:37

Now, the Galil, or, um, probe will talk about

11:42

being able to, on the way out, kind of heat the tract.

11:47

Um, I think they, at first, they used to tout it as being

11:51

a cautery, and now they no longer do that because it

11:54

doesn't act, from what I'm told, it doesn't actually

11:57

get up to the temperatures of a true cautery device.

12:01

Um, it is longer to treat with cryoablation than

12:06

with microwave or RFA, again, because you're, you

12:10

have two cycles. Typically, it'll be an initial

12:14

10-minute freeze cycle, followed by an eight-minute

12:17

passive thaw, followed by a second freeze cycle,

12:21

anywhere from eight to 10 minutes in length.

12:24

And then when you have an active thaw, that's going to take

12:27

some time in order to raise the temperature of the probe,

12:31

warm enough that you can remove it from the body safely.

12:36

In terms of workup and selection, as all of you

12:40

know, that typically renal masses, even very large

12:44

renal masses, are usually incidental findings.

12:47

Um, mostly because if they do have hematuria and everything

12:53

like that, it would have to be a very central type of tumor.

12:57

Um, I've had patients that have had, you

13:01

know, eight-, 10-centimeter tumors that have

13:05

been incidental because it has

13:07

not caused some pain whatsoever.

13:10

In terms of imaging, certainly you would want a

13:12

renal mass protocol, whether you're using CT or MRI.

13:16

I see all my patients in clinic, um,

13:19

even patients that are out of state.

13:21

The nice thing, I guess one of the, uh,

13:24

good outcomes, if you could say, of

13:26

COVID-19 is increase of telehealth.

13:30

And so that's been very helpful so that

13:33

patients don't have to take a long drive.

13:35

The University of Colorado happens to be a tertiary

13:38

care center, so we do get a lot of patients

13:40

that travel from far away, and so that's helpful.

13:44

Um, in terms of biopsy of renal masses,

13:47

there are some people that will

13:50

do it at the same time of the cryoablation.

13:54

Personally, I like to biopsy the tumor prior to doing

13:59

it at a separate session, and my rationale is that

14:04

up to, uh, 20% of the time in kind of sizes, like two-

14:10

centimeter tumors or whatnot, you could have a benign mass.

14:14

So I kind of feel that, uh,

14:18

you know, if you're doing the biopsy at the time of the

14:23

ablation, you are going to treat no matter what because of the

14:25

fact that you won't get the pathology results back in time

14:30

to know whether this is, say, a benign oncocytoma, and I

14:36

don't like to be doing procedures that may not be indicated

14:40

because while the risks of cryoablation or microwave or

14:47

RFA ablation are pretty low, um, that it is

14:51

increased compared to doing a renal biopsy.

14:56

However, if you have a patient who is on anticoagulation

15:00

or something like that where it would be difficult

15:04

to stop, or it's, you know, a much larger tumor

15:07

that we're doing, that the likelihood of this

15:10

not being an RCC or renal cell carcinoma is very, very low.

15:15

Then I will do the biopsy at the time of the

15:18

procedure. When I do that, however, I place the

15:22

probes first, and the reason I do that is that, um,

15:27

as many of you might know, is that when you

15:29

do a renal biopsy, it's not uncommon to get

15:33

a little bit of bleeding within the tumor.

15:36

And so if you biopsy first, you could potentially

15:40

obscure your margin and not know just how large or

15:44

where to place the probes in order to have that good

15:49

ablation margin of at least five millimeters.

15:54

So I like to place my probes first.

15:56

Once I've placed the probes and put it in what

15:58

we call a stick mode so they don't move, then

16:02

I will go ahead and do a single-core biopsy.

16:07

In terms of indications, T1a size RCC,

16:12

so less than four centimeters in size.

16:15

Patients who are poor surgical candidates, and a

16:18

lot of times these patients happen to be of advanced

16:21

age, um, patients who don't want or refuse surgery.

16:26

There are a lot of patients who like the

16:29

thought of having a minimally invasive

16:33

image-guided procedure as opposed to surgery.

16:37

If the patient has a solitary kidney, whether or

16:41

not that's because of prior nephrectomy or it being

16:44

congenital, or they have limited renal function.

16:48

Yes, partial nephrectomy is renal sparing, but I find that,

16:53

um, percutaneous ablation is going to

16:55

be even more renal sparing than surgery.

16:59

Certainly patients who have multiple RCCs or

17:02

something like on Hippel–Lindau, who are at risk

17:06

of forming RCCs throughout their lifetime.

17:09

And it's not uncommon that we're going to be

17:13

treating them subsequent times for additional

17:16

lesions that are probable RCCs, that it's

17:20

again, going to be more renal

17:23

sparing and preserve that tissue.

17:26

In terms of contraindications, there's relatively few.

17:30

An absolute one would be if there's some

17:34

uncorrectable coagulopathy or that they're not,

17:38

um, stable, and that would be rather unusual.

17:41

Again, renal cell carcinoma is typically a slow-

17:44

growing cancer, but maybe you have somebody who

17:48

is not stable.

17:49

And then from a medical standpoint, and so

17:52

this would not be an option, and you might be

17:54

doing active surveillance in those patients.

17:57

Relative contraindications would be tumors greater

18:01

than five centimeters in size because of the

18:04

increased risk of residual or recurrent tumor.

18:09

Or if they're in the hilum or central collecting

18:12

system where you could possibly cause a lot of

18:16

damage, but as I'll, I'll address in a minute,

18:19

that there are things that we can do to decrease

18:23

that risk of injuring the collecting system.

18:27

In terms of selection, the patients that

18:30

are really favorable are patients with

18:33

tumors that are exophytic or posterior.

18:36

Um, challenges are when they are

18:39

endophytic because, again, um,

18:42

greater risk of, uh, injuring the collecting system.

18:46

Also, a lot of times these are difficult to visualize

18:50

when you're doing non-contrast CT, and they might

18:54

be isoechoic on ultrasound, so even placement of

18:59

the probe under ultrasound may be different.

19:02

Um, in those instances, uh, I will give IV contrast.

19:07

A lot of times I will get everything set up.

19:10

I'll know from the prior imaging exactly where I'm looking

19:13

for, I'll have them go ahead and give the contrast.

19:17

I won't necessarily do another scan because, again, I know

19:22

from the planning, from the pre-procedure

19:25

imaging of where I'm looking for.

19:27

And so I want to maximize the amount of time that I have

19:31

where that IV contrast is on board with anterior lesions.

19:36

Again, in terms of positioning, certainly you would be

19:40

traversing more kidney if you have them in a prone position.

19:44

Um, I have done them supine.

19:46

Maybe, you know, you might need that

19:48

side or different side angled up.

19:51

A lateral decubitus position also works,

19:54

especially if it's more superior in location.

19:58

Um, if that's the case, if you have them in a prone

20:01

position, you may have the pleura in the way, and

20:05

certainly you want to minimize the chances of giving

20:09

them a pneumothorax by doing a percutaneous ablation.

20:13

And if I'm going to do a lateral decubitus,

20:17

because it's a more superior tumor, I will place that

20:21

side down because that minimizes the movement of the lung.

20:27

Um, and then again, if it's in close proximity to the ureter

20:32

or the collecting system, sometimes you're going to have to

20:35

ask your urology colleagues to place a retrograde stent.

20:40

You can connect to saline so that you

20:43

could be running saline at the time of the

20:46

procedure for that pyeloperfusion.

20:50

Um, some talk about using warm or heated saline.

20:54

Typically, I just use room temperature, and that's

20:57

good enough if you have close proximity to the

21:00

to the bowel or to, say, muscle or the abdominal wall.

21:06

You could either, uh, use fluid, whether it be

21:11

saline or D5W. Um, again, in this instance, it's

21:16

not like with, um, RFA, where you have to make sure that

21:20

you're using D5W, that you're not using normal saline.

21:24

With cryoablation, those ions don't matter,

21:27

so you can just use regular saline, um,

21:31

to push and perform hydrodissection.

21:35

I also like to use air for pneumodissection because

21:40

if you have hydrodissection, that fluid is still

21:44

going to freeze, but air is not going to freeze.

21:47

If you're going to maybe use a lot of, of say, pneumodissection,

21:53

you can also use CO₂ that's going to be

21:56

absorbed a little bit better, um, by the patient.

22:00

Um.

22:01

And, uh, another alternative that's been described

22:05

in the literature is actually to place a balloon.

22:08

Um, and that could be done as well to, again,

22:11

to protect those surrounding structures.

22:14

So let's go into a case.

22:16

This is a 61-year-old male who complained about back pain.

22:20

And again, this was an incidental finding.

22:23

A biopsy was performed at a separate session, and

22:28

this happened to be a chromophobe renal cell carcinoma.

22:33

And we put this patient in a prone position.

22:37

And you can see here that

22:40

typically there will be a marker on the Endocare system

22:44

at the tip, and then also three centimeters back,

22:48

so you can see where your active tip is.

22:54

But based on those charts, you're going to know that

22:58

the formation of the ice, as you can see here,

23:02

is much larger than that.

23:04

And so, um, this is what I talk about when

23:07

the ice ball is very visible, um, by CT.

23:12

If you were, again, doing this by ultrasound, um, you

23:16

would not see the back portion of that ice ball.

23:19

And while I'm sure things can be done MRI-guided, I

23:24

personally have not done an ablation using MRI guidance.

23:28

Um, at our hospital, uh, they'd rather

23:31

be doing MRI scans, um, versus us taking

23:37

scanner time away to be doing a procedure.

23:40

And then this is after the probe has been removed.

23:44

You can still see that

23:47

there is ice.

23:49

This is the lesion again itself.

23:51

It's not uncommon to kind of see this void where

23:55

the probe is, and it's also not uncommon that

23:58

sometimes that this can be a little bit hyperdense.

24:02

When I first started to do this,

24:05

it, uh, kind of unnerved me that it was hyperdense

24:08

because I thought that was bleeding, um, and hemorrhage.

24:13

But I think what the reason you get that is

24:16

because you've had heating that, that at that

24:19

area you just might get initially it to be

24:22

hyperdense, but haven't had necessarily, uh, used

24:27

that or seen that as, uh, hemorrhage or hematoma.

24:32

And then this was one month post cryoablation.

24:36

So I always warn my patients, especially if

24:40

they happen to go and get a scan that is not

24:45

local, or maybe some ER where they don't have

24:49

a history that they have ablation, if that,

24:52

they compare it to the prior, you may have somebody

24:56

who's going to say, oh my goodness, um, this lesion

24:59

has grown, and there'll be warning bells going off.

25:03

And all it is is the ablation zone that I've

25:07

purposely made larger than the lesion itself.

25:11

And then in this instance, this is, um, the scan,

25:15

four years post cryoablation, um, no enhancement.

25:19

It's not uncommon to get, uh, basically areas of

25:23

calcification, and it's not uncommon that there's just

25:28

been fat pulled into this ablation zone, which is scar.

25:34

In this patient, this is a patient with Von Hippel–Lindau,

25:37

43-year-old male with bilateral renal masses.

25:41

This happens to be on his left kidney, and you can see on

25:45

the T1 fat-sat VIBE pre, and then on the post that we've

25:50

got, you know, this lesion here, and then a little bit of

25:55

some enhancement here, and it can be pretty central.

25:59

And you can wonder if that, you know, again,

26:03

multiple ones in this, on this one site.

26:08

And here, like I said, that when we're doing

26:10

it by CT, most of the time, you know, you're

26:13

not necessarily doing it with contrast.

26:17

And here are multiple probes,

26:20

um,

26:21

at different locations, both on the axial plane

26:25

and then cranial-caudal, and you can see that

26:28

this probe is quite central near the hilum.

26:32

So in this patient, again, because it was so

26:35

close centrally, and I was concerned about having

26:39

a urine leak, if you're too close to the ureter,

26:42

without pyeloperfusion, you could

26:44

have stricture of that ureter.

26:47

So in this one, I did ask for a retrograde ureteral

26:50

stent placement for pyeloperfusion because of the size.

26:54

And typically I use, uh, in terms of they do have

26:59

charts in terms of the number of probes to use per size.

27:03

But a good general rule of thumb is

27:06

one probe for every centimeter size of the tumor.

27:10

So in this one, I used four of the PR-24 probes.

27:14

I did do a biopsy at the time of the ablation because,

27:19

again, him being found Hippel–Lindau, the likelihood of

27:22

most of these being renal cell carcinomas was very high.

27:26

And then that did come back as clear

27:28

cell, um, renal cell carcinoma.

27:31

And here is, you can see the, uh, reformat.

27:36

In terms of the post, this is basically, again,

27:42

pre- and post-ablation at seven months, and you

27:46

can see that there's no enhancement and that the,

27:51

that it has really scarred down and just showing

27:54

you the, uh, fat-sat VIBE post-treatment to

27:59

show just how well, um, of an ablation we did get.

28:05

This patient is a 55-year-old male

28:08

who complained about back pain.

28:12

Um, this was his mass pre-treatment.

28:16

He happened to have a laparoscopic

28:19

cryoablation at an outside hospital.

28:23

And this was the scan post-ablation.

28:27

And you can see that while some of the

28:31

tumor has been treated, there's a pretty

28:34

large residual, um, portion of the cancer.

28:39

Um, I did biopsy this previously,

28:43

and it was clear cell renal cell.

28:45

Just to confirm what we thought, that the ablation

28:50

that was done laparoscopically was incomplete, and

28:54

in this one we did, because of the colon nearby,

28:59

and again, because of the size of the probes

29:03

that I was using, that basically I didn't

29:06

want to, uh, freeze any of the muscle here.

29:10

I did use pneumodissection here.

29:13

Okay.

29:15

Post, I typically will do, uh, a non-contrast

29:19

scan through the area at the time, uh, after I've

29:23

removed the probes, and you can see that there

29:26

was a little bit of bleeding after the procedure.

29:31

Um, that

29:33

interestingly enough went into kind of that

29:36

negative space where I had injected the air.

29:39

Um, we watched the patient afterwards.

29:42

Um, if you're concerned about, um,

29:45

you know, bleeding and everything like that, you

29:48

could certainly do a contrasted CT scan or be

29:52

monitoring them, watching vital signs and checking,

29:57

you know, serial hematocrits, that type of thing.

29:59

Um, this patient, uh, actually was fine.

30:04

Blood pressure stayed stable, not a

30:07

problem, and went home as an outpatient.

30:11

He did complain about some back pain, but

30:14

the problem was that he had the back pain he

30:17

said was similar to the back pain that he had,

30:20

um, normally. We brought him back

30:23

for a one-month post-cryoablation.

30:26

Scan, and I saw this, and I immediately called him up, told

30:31

him to get to the ER because, you know, this was hemorrhage.

30:36

We had him come through the ER, and you could see

30:38

that there was a very significant hemoglobin

30:42

drop compared to the labs that I had at the time.

30:47

And you can see we have this very, very large, um, hematoma.

30:53

That was accounting for his pain.

30:56

Um, we watched him overnight, did not

30:58

have to do any additional therapy, and

31:02

over time, that hematoma did resolve.

31:06

Um, in terms of why this one bled, I don't know if it

31:11

had to do with the fact that he had previous intervention

31:15

from the laparoscopic, uh, procedure or, or what.

31:20

Um, I really don't know.

31:21

I have had a few instances where there's been

31:25

no prior surgery where they have had a hematoma.

31:29

So again, that leads us to complications.

31:33

Reported rates of major complications are 3% to 7%.

31:38

Probably one of the higher ones is going to be

31:41

bleeding, with, again, you don't have that cautery effect.

31:45

Say if you were doing radiofrequency

31:47

ablation or microwave, if the tumor is

31:52

Renal Cryoablation, Dr. Kimi Kondo (3-29-21)

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