2. NORMAL ANATOMY
⚫Conical, round or hemispherical shape.
⚫ Comprised of 15-20 lobes, each encased in
fascial sheath defined byAMF & PMF
⚫ Extends from 2nd or 3rd intercostal space to 6th
or 7th intercostal space
⚫ Extends laterally to anterior axillary fold and
medially to lateral sternum
3. Relationship to chest wall
⚫Superior two-thirds overlies pectoralis major
muscle
⚫Lateral portions overlies serratus anterior muscle
⚫ Inferior-most margin overlies upper
abdominaloblique muscles
⚫ Axillary tail of Spence: Extension of normal
breast tissue toward axilla.
4. ZONALANATOMY
Premammary (Subcutaneous) Zone
⚫Most superficial zone.
⚫Anterior margin defined by skin, posterior margin
defined byAMF.
⚫ Contains subcutaneous fat, blood vessels, anterior
suspensory (Cooper) ligaments, formed from two
leaflets ofAMF inserting into dermis which provides
support for breast and is usually visible on
mammograms and sonograms.
5. Mammary Zone
⚫Defined anteriorly byAMF and posteriorly by PMF
⚫Contains majority of ducts/TDLUs (Terminal dust
lobular units), stromal fat and stromal connective
tissue
⚫Subdivided haphazardly by interspersedASLs.
Retromammary Zone
⚫Most posterior of three zones
⚫Defined anteriorly by PMF and posteriorly by chest
wall
⚫ Contains fat and PSLs which attach PMF to chest wall
10. GENERATOR
• High voltage generator used-more efficient x rays produced.
• 20-40KVP of xray energy is required for good contrast.
• High frequency generator works on single phase and provides rectified
smoothed voltage supply to the tube with ripple factor of about 1%.
• They are smaller in size with good reproducibility and capable of providing
up to 600 mAs.
11. X RAYTUBE
• Only characteristic x rays are produced which are of low KVP and high
mAs.
• Cathode – dual filament in focusing cup with focal spot size 0.3-0.4 and 0.1-
0.15 mm (for magnification)
• Anode -rotating ,SID – 65cm.
• Small focal spot
• minimizes geometric blurring
• maintains spatial resolution
• The tube is tilted by about 25 degrees to minimize the effective
focal spot size.
12. The anode is mounted on a molybdenum
stem, which is attached to a bearing with rotor
and stator assembly.
In mammography, in addition to the anode tilt,
tube tilt is also incorporated.
Hence, the term effective anode angle is used.
It is defined as the anode angle relative to the
horizontal tube mount.
The effective anode angle is about 22–24°, for
a source to image distance of 65 cm.
This can be achieved either by 0° anode angle
and 24° tube tilt or 16° anode tilt and 6° tube
tilt
13. Magnification
• Advantages
• Magnification of 1.5x to 2.0x is
used
• Increased effective resolution of
the image receptor by the
magnification factor
• Small focal spot size used
• Reduction of scatter
• Disadvantages
• Geometric blurring caused by the
finite focal spot size (more on
cathode side)
• High breast dose (in general
similar to contact mammography)
14. HEEL EFFECT
Shape of the breast requires higher
intensity of radiation near the chest wall, to
create uniform exposure to the screen-film
.
The cathode is positioned toward the chest
wall and the anode is toward the nipple .
Permits easy positioning of the patient .
Increases the intensity of radiation near
the chest wall, where greater penetration
is needed .
The anode is often grounded with zero
potential and the cathode is given higher
potential .
15. TARGET MATERIAL
• 3 Types-1)Molybdenum-m/c used-produce low kvp radiation
2)Specialised tungsten
3)Rhodium
Tungsten and rhodium are used for dense breast tissue.
TUBE PORT
•1-mm thick Beryllium used as the tube port
• Beryllium provides both low attenuation and good structural integrity
16. FILTERS
• Common Targets/filters in mammography include
• Mo/Mo
• Rh/Rh
• Mo/Rh
• A Mo target with Rh filter are common for imaging thicker and
denser breasts
• Generally, filter material is same as target material.This will
allow its K characteristic X-rays to reach the breast, and suppress
the low and high energy bremsstrahlung X-rays.
17.
18. Compression
• Breast compression is necessary
• it reduces overlapping anatomy and decreases tissue thickness of the breast
• less scatter, more contrast, less geometric blurring of the anatomic
structures, less motion and lower radiation dose to the tissues
19. • Compression is achieved with a low
attenuating lexan paddle attached
to a compression device
• 10 to 20 newtons (22 to 44
pounds) of force is typically used
• A flat, 90°paddle (not curved)
provides a uniform density image
• Parallel to the breast support table
• Principal drawback of compression
is patient discomfort
20. COMPRESSION PEDDLE ADVANTAGES
(i) Decreases the thickness of the breast , thus reduces the scattered radiation –
improves the contrast .
(ii) Decreases the kinetic blur .
(iii) Reduces geometric unsharpness by homogenously bringing the object
close to the film .
(iv) Makes breast thickness uniform in film density.
21. (v) Differentiates the easily compressible cysts and fibro-
glandular tissue from the more rigid carcinomas
Separates the super imposed breast lesions
(vi)
(vii) Reduces radiation dose to the breast tissue .
22. GRIDS
Stationary grids or grids placed in between the
screen and the film are no longer used as the thin
grid lines compromised on the quality of the image .
Hence oscillating grids are used with Linear Grid
ratio of 4:1 or 5:1
The grid lines are eliminated by the motion of the
grid .
Currently, high transmission cellular grid
(HTC) is employed. It is basically crossed
grid with grid ratio of 3.8:1, which
reduces radiation in two directions.
23. AUTOMATIC EXPOSURE CONTROL
AEC system employs phototimers to measure the
Xray intensity and quality .
Kept closer to the image receptor , to minimize the
object to image distance – improves spatial
resolution .
TWO TYPES :
(i)Ionization chamber type
(ii) Solid state diode type
25. Difference between Mammography and General
X-ray tube
• Mammography
•Anode made up of Rh/Mo.
•Anode angle increased up to 24
degrees.
•Tube angulated.
•Low kvp used: 22-40kvp
•SID: 65 cm
•Focal spot size: 0.3mm and 0.1mm
•Produces low energy x-rays.
•Single emulsion film used.
• General X-Ray tube
•Anode made up of Tungsten.
•Anode angle is up to 16 degrees.
•Horizontal tube.
•Larger kvp used: more than 40kvp
•SID: 108 cm
•Focal spot size: 1.0mm and 1.2mm
•Produces higher energy x-rays than
mammography.
•Double emulsion film used.
26. PATIENTPREPARATION:
Explanation of procedure to the patient.
The patient should be asked to change into hospital gown
Should be instructed not to put on talcum powder/
breasts on the
/deodorant/antiperspirant/lotion under arms or on
day of mammogram as can mimic calcium spots.
9
27.
28. CRANIO-CAUDAL (CC)VIEW
The casette is placed under the breast
at the level of the inframammary fold .
The breast is then pulled until the
inframammary fold is taut .
Compression is applied and Xray beam is
directed vertically from above .
Postero medial aspect should also be
included .
Central x ray beam targeted towards
center of breast.
29. Essential image characteristics
• No overlying structures should be seen.
• The pectoral muscle will be seen in 30–40% of patients.
• The nipple should be in profile and shown medial to the midline of
the film.
• The medial portion of the breast should be included on the film.
• There should be no folds in the breast tissue.
30.
31. MEDIOLATERAL OBLIQUE(MLO) VIEW
Best view to image all of the breast tissue
and the pectoral muscle .
The C-arm of the mammographic unit is
rotated to 45 degree so that the cassette is
parallel to the pectoral muscle .
The film holder is kept high up in the axillary
fossa and the patient s arm is abducted at
the elbow by 80degrees.
The xray beam enters the breast from the
medial side –compression is applied to the
pectoralis major muscle .
32. Essential image characteristics
• The axilla, axillary tail, glandular tissue, pectoral muscle and infra-
mammary fold should be demonstrated.
• The pectoral muscle should be demonstrated to nipple level.
• When both medio-lateral oblique projections are viewed together
‘mirror image’, they should be symmetrical, matching at the level of
the pectoral muscle as a deep ‘V’ and at the inferior border of the
breasts.
33.
34.
35.
36. SUPPLEMENTARYVIEWS
1. Lateral projections (mediolateral/lateromedial)
2. Extended craniocaudal projection
3. Cone down compression view
4. 90 degrees lateral view and angled craniocaudal
views
5. Tangential views in palpable masses
6. Spot and magnification views
7. Cleavage view.
37.
38. ▶ Axillary view
▶ also known as a "Cleopatra view”
▶ Valuable in women where lymph gland
involvement of a breast carcinoma is
suspected or there is accessory breast tissue.
▶ Demonstrate of entire axillary tail (separation
of parenchyma from thoracic wall indicates
that all of axillary has been shown).
▶ Lateromedial oblique (LMO)
▶ Improved visualization of superomedial tissue
▶ Improved tissue visualization and comfort for
women with pectus excavatum, recent
sternotomy, prominent pacemaker
39. ▶ Tangential (TAN) view
▶ Verify skin lesions, to locate skin
calcification or lesions considered to be
near skin
▶ for palpable lesions that are obscured
by surrounding dense glandular tissue
on mammogram.
▶ Cleavage view
▶ Show lesions deep in posteromedial
breast not seen in CC view
▶ To view postero-medial portion of both
breasts
40. DIGITAL MAMMOGRAPHY
The stages in digital imaging :
1. Image capture by digital detector
2. Conversion of latent image into digital data set
3. Processing of image data
4. Display of processed image
5. Transmission and archival of data set
