Ch. 23 Mammography
____% of men's cancer deaths are from breast cancer
.22%
The ratio of benefit (lives saved) to risk (possible deaths) caused because of radiation induced breast cancer is
1,000 to 1
Women's risk of breast cancer include
1. Age 2. Family history 3. Genetics 4. Early menstruation 5. Late menopause 6. Late age at birth of first child or no children
What are the two leading causes of death from cancer in women
1. Lung Cancer 2. Breast Cancer
Breast cancer is how much more common in women that men
100 times
The x-rays mot useful for enhancing differential absorption in breast tissue & for maximum contrast range from ___to___keV
17 to 24 keV
Mammography was first attempted in what year
1920's
In what year did the U.S. Gov. mandate regulations in mammography to set standards for image quality, patient dose, personnel qualifications,& exam procedures
1992
Compression is ___-___ lbs of force for a breast exam
25-45 lbs of force
How many new cases of breast cancer are found each year & how many deaths do they cause in the U.S
260,000 new cases 40,000 deaths
The x-ray beam should be filtered with ___to ___mm of molybdenum or rhodium to accentuate the characteristic x-ray emission
30 to 60 mm
Screening women in the ___to___ year age group is beneficial in reducing mortality
40 to 49
Breast cancer is one of the leading causes of death among women between the ages of ___&____
40-50 years old
Screening mammography in patients ____years or older reduces cancer mortality
50 years
1 out of every ___ women will develop breast cancer during her lifetime
8
Approximately ___% of breast cancer is ductal & may have deposits of microcalifications smaller then approx___mm
80% ; 500 mm
With early detection more than ___ % of women diagnosed with early stage disease will survive
90%
First radio graphic exam of the breasts before age 40 used for comparison with future mammograms
Baseline Mammogram
In conventional radiography, subject contrast is great because of large differences in mass density & atomic number in
Bone, muscle, fat, lung tissue
When vigorous compression is used all tissue is brought closer or farther to the image receptor
Closer
Exam performed on patients with symptoms or elevated risk factors. Two or three views of each breast may be required
Diagnostic mammography
Normal breasts consist of three principal tissues
Fibrous, glandular, & adipose (fat)
Young breasts are dense & more difficult to image because of_________ tissue, older breasts are more _____ & easier to image
Glandular ; Fatty
Which breast tissue is most sensitive to cancer radiation
Glandular tissue
Colors on a mammogram Hypo= Hyper=
Hypo=dark colors Hyper=light colors
Post menopausal breasts are characterized by a degeneration of fibroglandular tissue & increase in adipose tissue which appears dark on film & requires____ radiation exposure
Less
High or low kVp must be used to maximize the photoelectric effect to enhance differential abs absorption & contrast resolution
Low kVP
Hybrid imaging includes what two exams
MRI & PET exam
A prime example of soft tissue radiography
Mammography
Molybdenum & rhodium k-characteristic x-rays have energy that is most effective for Brest imaging. All manufactured mammography imaging systems have target filter combinations of
Mo- Mo Mo- Rh Rh- Rh
Mammography became clinically acceptable with the introduction of___ as the target & filter
Molybdenum
Compression immobilzes the breast & reduces
Motion blur
In soft tissue radiography only ___&____ are imaged
Muscle & Fat *Have similar effective atomic numbers & similar mass densities
L-shell x-rays are all absorbed and contribute only to ___ dose * not to the image
Patient dose
At low x-ray energy ___ absorption predominates over ___scattering
Photoelectric ; Compton
Mammographic exam performed on a symptomatic women sight he use of a two-view protocol; usually medial lateral oblique & cranial caudal to detect an unsuspected cancer
Screening Mammography
Clues that it is cancer in a mammogram
Sharp edges
Soft tissue radio graphic techniques are designed to enhance differential absorption in ____ tissues
Similar
Compression improves spatial resolution & contrast resolution & reduces patient dose *T/F
True
Compression is important in conventional radiology & mammography with several advantages * T/ F
True
Compression reduces absorption blur & scatter radiation *T/F
True
Early detection of breast cancer leads to more effective treatment
True
If a malignancy is present it appears as a distortion of normal ductal & connective tissue patterns
True
Radiation can cause as well as detect breast cancer
True
A compressed breast riser near the chest wall is less likely to be_____exposed and tissue near the nipple is less likely to be_____exposed
Under exposed; Over exposed
A compressed breast has more ___thickness
Uniform
The optimum degree of compression is
Unknown *The more vigorous the compression the better the image & lower the dose. But the higher the level of patient discomfort
The incidence of breast cancer is highest in what quadrant of the breast
Upper lateral quadrant
X-ray mammography requires low kVp. As kVp is reduced, the penetrability of the x-ray beam is reduced, which requires an increase in___
mAs