0:00

So let's look at the coaxial technique.

0:03

Here, we have a radiologist performing a sampling of

0:06

tissue by placing the biopsy needle

0:09

directly through the introducer the right hand

0:12

of the individual is on the deployment mechanism and

0:15

this introducer is

0:18

actually being held and stabilized with

0:21

the left hand. So what is the beautiful thing about the coaxial technique

0:24

a coaxial technique is particularly helpful

0:27

because the introducer is Advanced just in

0:30

distance to allow for a throw of the

0:33

biopsy needle into the target at anatomic site.

0:36

So imagine the introducer is just within

0:39

striking range. And so what we

0:42

can do is we can remove the biopsy needle after the first

0:45

biops. He's taken and then replace

0:48

That perhapsy needle after that sample has been

0:51

harvested so we can take multiple samples in the

0:54

same location without oven to Traverse the skin.

0:58

The soft tissues and any other sites of interest on our

1:01

route to achieve that tissue sample. So repeated

1:04

punctures that may actually pose

1:07

risks to the surrounding territory are minimized

1:10

in the setting of a coaxial technique. What we're

1:13

doing here is again placing an

1:16

introducer and that introducer allows us again to

1:19

take repeated samples.

1:22

one of the things that I want to draw your attention to is imagine

1:25

if there's risk for bleeding we

1:28

would know that that risk for bleeding is secondary to

1:32

tissues that would have been traversed that blood

1:35

would be emanating from the

1:38

holobore of that introducer and if there is a

1:41

need in order to

1:43

embolize that track which we'll talk about in a bit we can do so through

1:46

that introducer needle because of the coaxial technique,

1:49

but imagine if we didn't have that introduce a

1:52

needle in place. Imagine if we went directly in with that

1:55

biopsy needle through this skin through the

1:58

soft tissues took a biopsy remove the map

2:01

see needle harvested the tissue went back and again,

2:04

how would we know if the tissue is bleeding? We may

2:07

not know until it declares itself. So the use of the coaxial technique

2:10

allows us direct entry to

2:13

that site in order to perform the

2:16

repeated biopsy safely, but also to

2:19

perform embolization techniques, which we'll talk about in a bit.

2:22

Question for you, an IR is performing

2:25

corneal biops with coaxial technique with an 18 gauge needle.

2:28

What should be the size of the external coaxial needle or

2:31

introducer?

2:32

Is a 20 gauge?

2:34

a 10 gauge

2:37

is a 25 gauge or is it 17 gauge?

2:41

If you said 17 gauge you would be spot on.

2:45

So the coaxial needle which is the introducer maintains

2:48

the position. Okay, and it should

2:51

be approximately one gauge larger than the biopsy. So

2:54

one gauge larger would if it's 18 gauge would be

2:57

17 gauge given that the gauge as it

3:00

decreases in Number the bore

3:03

the girth of the needle increases

3:06

in size.