190 Mammography

Front 1

kVp range used in mammography

Back 1

20 - 35 kVp

Front 2

Two advantages of using low kVp in mammography are:

Back 2

Producing high radiographic contrast
Producing a very low energy x-ray beam

Front 3

The anode heel effect can be used in mammography by positioning the ______ toward the ______ wall

Back 3

cathode
chest

Front 4

Breast tissue is made up of what 3 tissues?

Back 4

Adipose tissue
Fibrous tissue
Glandular tissue

Front 5

Anodes used in mammography are typically made of what?

Back 5

Molybdenum

Front 6

The exit window of the x-ray tube in mammography can be made of what two materials?

Back 6

Beryllium and borosilicate glass

Front 7

Magnification projections of the breast provide what three things?

Back 7

Increased resolution
Reduction in scatter radiation
Improved visibility of detail

Front 8

The use of a grid in mammography does what three things?

Back 8

Improves radiographic quality
Increases patient dose
Reduces scatter reaching the image receptor

Front 9

Breast compression will reduce ______

Back 9

magnification

Front 10

Breast tissue has very _____ inherent subject contrast

Back 10

low

Front 11

AEC's should not be used for mammography (true/fasle)

Back 11

False

Front 12

Magnification radiography of the breast ______ patient exposure

Back 12

increases

Front 13

What is the focal spot size range used in mammography?

Back 13

0.1 - 0.6 mm

Front 14

When magnification mammography is used, the magnification factor used is in what range?

Back 14

1.5 - 2

Front 15

Molybdenum is used in mammography x-ray tube targets to create useful _______ characteristic x-rays

Back 15

characteristic

Front 16

The low kVp used in mammography will increase what ?

Back 16

photoelectric absorption

Front 17

Quality mammograms can't be produced at high 90 kVp because differential absorption is too ____

Back 17

low

Front 18

Compared to a general diagnostic x-ray unit, the half value layer of a mammography x-ray unit is very _____

Back 18

low

Front 19

What is the minimal total tube filtration of a mammography x-ray unit?

Back 19

0.5 mm Al equivalent

Front 20

The increased photoelectric interactions from using a low kVp will create ____ contrast, and ______ patient dose

Back 20

higher
higher

Front 21

Dedicated mammography x-ray units use what type of generator?

Back 21

High frequency (1% ripple factor)

Front 22

The majority of the beam is made up of what type of radiation?

Back 22

Characteristic

Front 23

What energy range of photons will maximize subject contrast, and allow the visualization of microcalcifications?

Back 23

17-20 keV

Front 24

If the energy levels of the beam are too high:
1. Breast tissue will be ____ penetrated
2. produce _____ scatter
3. ______ image contrast

Back 24

1. over
2. more
3. decrease

Front 25

A smaller focal spot will ______ recorded detail

Back 25

increase

Front 26

Beryllium is used as in the port window to allow _______ energy photons to exit the tube.

Back 26

low

Front 27

Two geometric problems to overcome are:

Back 27

1. Decreased resolution at chest wall
2. Missed tissue along chest wall

Front 28

The geometric problems are compensated by what 3 things?

Back 28

1. Heel effect
2. Off center placement of the tube
3. Elimination of cathode side of the beam

Front 29

The heel effect is very pronounced due to what?

Back 29

Short SID

Front 30

Tube configuration uses effect to an advantage by placing the _______ toward the chest wall and the _____ toward the nipple

Back 30

cathode
anode

Front 31

The ______ axis is used to line up the tube

Back 31

reference

Front 32

The effective target angle of the anode is:

Back 32

22-24 degrees
(more than general x-ray due to SID, off centering, and anode heel effect)

Front 33

Compression of the breast (25-45 lbs) will do what 3 things?

Back 33

1. Improve spatial resolution (see more anatomical tissue)
2. Improve contrast
3. Lower patient dose

Front 34

Mammography screen film systems use ______ emulsion film and _____ intensifying screen

Back 34

single
one

Front 35

Selenuim direct capture detector has a direct converesion of x-ray energy to what?

Back 35

Electrical signal

Front 36

1 in __ woman will develop brest cancer

Back 36

8

Front 37

At low energy _____ predominates over compton scattering

Back 37

photoelectric absorption

Front 38

low kvp must be used to maximize _________ effect

Back 38

photoelectric