0:00

So why do we give pain to the patient?

0:03

Compression is very critical in mammography,

0:06

and I'm going to talk about why that is in the next few slides.

0:09

When I say compression, that is very necessary in mammography.

0:14

First and foremost, it reduces overlapping anatomy

0:19

and decreases tissue thickness because this is an

0:22

uncompromised breast with no compression.

0:26

Look at here, the scatter to primary ratio is 0.21.

0:31

So, lot of scatter and there's lot of overlapping

0:35

object, very difficult to separate them

0:39

because a three-dimensional object is imaging to a planar image,

0:42

mammography image.

0:44

To reduce the scatter to primary ratio, we do

0:48

multiple ways. We use what is called as a grid, that is first thing.

0:52

Second thing is we compress the breast.

0:54

When you compress the breast, it actually reduces

0:58

the overlay of the anatomy, spreads it

1:02

on the breast table. At the same time, it will reduce the

1:06

scatter to primary ratio quite significantly.

1:10

In addition, the breast does not move when you take an image,

1:14

so the chances of motion artifact is gone.

1:18

So the breast compression is necessary,

1:21

which results in less scatter,

1:24

which provides more contrast. It also results in less

1:28

geometric blurring of anatomic structure,

1:32

less motion,

1:33

and more so, it lowers the radiation doses required to the

1:37

tissues.

1:39

And that's why it's done. And also that's why a lot of

1:43

people who come for screening mammogram on a yearly basis or a biannual

1:47

basis hate that experience because the breast is

1:51

compressed to a large extent.

1:53

So, the compression paddle is parallel to breast support,

1:58

or it can be right angle to the chest wall.

1:59

The purpose is the compression also tries to draw the

2:03

tissues away from that chest wall where the predominant breast

2:07

cancers are found. So you want to position and pull the breast

2:11

image as much as possible closest to the chest wall.

2:15

The advantage of compression is reduces scatter,

2:19

it reduces geometric unsharpness,

2:22

it reduces less superposition of the anatomy,

2:26

it results in a higher contrast film,

2:29

and also the patient dose is reduced, and it reduces

2:33

motion unsharpness.