0:00

Challenge number three.

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So what's the issue here with this area

0:05

of non mass enhancement?

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Gimme a moment to think about it.

0:10

What problems are we going to run into?

0:13

Well, here's the problem.

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This lesion is under eight millimeters

0:17

from the skin's surface.

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And the problem that can happen if you do this is

0:23

that you can biopsy in a significant amount of tissue, um,

0:28

not just the lesion here, but you take the skin

0:30

and you can actually, with the, um, vacuum going full force,

0:35

if you go round a couple of times, you're doing 12 biopsies,

0:37

you can take a three centimeter chunk of skin

0:43

out of the patient's breast.

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Now ask me how I know that I only did it once,

0:48

but I'm very cautious about it ever since.

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And this is what happens.

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So your average chamber of the standard needle is usually

0:57

around two centimeters, depending what needle you're using.

1:01

You're usually aiming to have the lesion sometime, somewhere

1:04

around the middle of the chamber.

1:05

So you can take out this big chunk of skin

1:08

adding to your complexity.

1:09

Don't forget that you have your needle block set

1:13

in your grid right here.

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So you can't see that patient's, uh,

1:19

skin surface while you're doing the scan.

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It's hidden behind the block, which is kind

1:23

of a pretty scary thing.

1:25

A big clue that you might be getting skin is if

1:27

you hear noise like this.

1:30

So if you hear something that sounds like somebody drinking

1:32

through a straw from the bottom of their glass, your vacuum

1:36

is sucking air in from the outside, which you don't want it

1:40

to do, and that may well mean that you are too superficial

1:43

and you are taking a skin biopsy.

1:47

So what can we do in this case?

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There's a couple of different things

1:50

that we can do that can be really helpful.

1:52

So I will put in a lot of superficial lidocaine to push

1:56

that lesion deeper.

1:57

Now you've gotta move quick in that situation

1:59

because that sort of lidocaine buffer doesn't last very

2:02

long, but it's worth doing it.

2:04

So put a whole load of lidocaine in

2:06

and sort of push it away from the skin.

2:09

You can take your regular cannula

2:11

and I'll show you a diagram in the minute

2:13

and your regular needle

2:15

and just push that biopsy chamber further into the breast.

2:19

So the lesion, instead of being in the middle

2:21

of the biopsy chamber,

2:22

is more towards the proximal range of the chamber.

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Now the advantage with doing this

2:27

with a regular needle is you are

2:28

still maintaining good sampling.

2:31

As you can see, one of my other options here is

2:33

to use the petite needle, whatever your version for your,

2:36

um, needle supplier is using.

2:38

And that's usually a needle

2:39

that's about a one centimeter chamber rather than a

2:43

two centimeter chamber.

2:44

And that's obviously gonna help my concerns about the petite

2:47

needle, which is why I don't use it unless I have to,

2:50

and we'll talk where we need to use it in a minute is

2:52

that you are reducing your volume of your samples by 50%.

2:56

So you are increasing the chance of

2:58

You, you having a sampling error.

3:01

Another thing that I always do is I make sure

3:04

that the skin is protected by the outer plastic cannula

3:07

that the needle goes within.

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So you want to make sure that that cannula,

3:13

if I'm doing drawing a skin nick here

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and the outer cannula, you want to be through the skin,

3:23

make sure, and it tends to kind of catch on that skin.

3:26

So it tends to want to kind of pull that skin in.

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You don't want that. You wanna make sure that cannula is

3:30

through the skin and then the needle just can't cut the skin

3:35

if you've got it protected by that.

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Um, can't not be good at drawing

3:41

and talking at the same time if you have it protected by

3:43

that outer cannula.

3:45

And the way that I do that is I put the cannula

3:48

and the needle, the needle through the cannula, the cannula

3:51

through the block,

3:53

but I don't push the block up tight to the skin, which is

3:58

where you want it to end up being until I've pushed

4:01

that cannula through.

4:02

So I wiggle it around, rotate it from side to side,

4:05

that tends to help get that cannula

4:08

all the way through the skin.

4:10

Second thing we can do is

4:12

that we can not use the block at all.

4:14

Now, I've done this in patients

4:16

who have very superficial lesions that I'm really concerned

4:19

that I'm gonna end up biopsying that skin.

4:23

And so we don't use the block,

4:25

we still make the same skin nick,

4:27

and we do it freehand without that needle guide.

4:29

Now it's a little tricky. Um, you have to have some sort

4:32

of silk tape to just hold the, um, cannula

4:36

and fiduciary in position, usually against the roof

4:38

of the grid while you're doing it.

4:40

But it does mean you can watch the skin every

4:43

minute while you're doing it.

4:44

It's not sort of my funnest way of doing biopsies,

4:47

but last resort I would do that.

4:48

And then our final way is to use a petite needle.

4:53

So let's just look at how we use that.

4:56

So here's a regular deep lesion, plenty of distance

4:59

between the lesion and the skin

5:01

with our regular two centimeter chamber.

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Put the lesion in the middle, no problem.

5:06

Here's our superficial lesion,

5:08

which I showed you on a diagram before.

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If we put in the middle of the needle,

5:11

would end up biopsying a big chunk outta the skin,

5:14

but I've pushed that needle in further to make sure that

5:18

that lesion is in the proximal end of the cavity of the, uh,

5:21

biopsy chamber and I'm still below the skin.

5:24

And then this third way is to add, use the petite needle.

5:28

The petite needle usually has a blunt tip

5:30

for reasons that we'll see in a minute.

5:31

Not a sharp tip, but you do get half the sampling

5:34

that you do with the regular needle.