The document summarizes key aspects of breast anatomy and mammography. It describes: 1. The functional unit of the breast is the TDLU, which consists of a lobule and terminal duct. Each lobule contains intralobular terminal ducts, ductules, and fibrous tissue. 2. Mammography equipment includes an X-ray tube, target, compression device, and image receptor. Digital mammography uses detectors rather than film. 3. Standard mammogram views are craniocaudal and mediolateral oblique. Additional views may be needed. Common findings include masses, calcifications, asymmetries, and architectural distortions.

1. ANATOMY
• Modified sweat gland.
• 15-20 lobes
• Functional unit of breast is TDLU, which
consists of a lobule and its extra lobular
terminal duct.
• Each lobule consists of intralobular
segment of terminal ducts, ductules,
loose intra lobular stromal fibrous
tissue.
• TDLUs–site of most breast pathology
and ANDIs

2. Mammography and Tomosynthesis
• Dr Shamim Hyder Kalenchira

4. Lymphatic drainage
• Axillary or lateral pathway
– fed by Sappey’s Plexus, as well as by ducts satellite
lymphatics and by most of the parenchymal
lymphatics
– this pathway runs around the inferior edge of
the pectoralis major and reach the pectoral group
of axillary nodes
• internal mammary pathway
– originates from both the lateral and medial halves
of the breast and passes through the pectoralis
major; connections may lead across the median
plane and hence to the contralateral breast
• retromammary pathway
– comes from the posterior portion of the breast

5. Lymphatic drainage
• Lymph of the breast drains as:
– About 75% into axillary nodes(anterior group)
– 20% ---- internal mammary nodes
– 5% ---- posterior intercostal nodes
• Internal mammary nodes drain the lymph not
only from the inner half of the breast,but from
the outer half as well there is a tendency for the
lateral part of the breast to drain towards the
axilla and the medial part to the internal
mammary chain
• Subareolar plexus of Sappey – plexus of lymph
vessel present deep to the areola

7. MAMMOGRAPHY

8. Mammography equipment
• Generator
• Xray tube- fine focus of 0.2-0.5 mm with an additional 0.1mm
focus for magnification.
• Target- Molybdenum and rhodium.
• Beryllium window-minimises absorption of radiation within
the tube.
• Molybdenum filter- by transmitting only characteristic
radiation, absorbs unwanted radiation and forms a
monoenergetic beam.
• Compression device: 1-4mm thick plastic plate.

10. TARGET
• The xray tubes are designed with tungsten, molybdenum ,
rhodium targets.
• Tungsten target is operated under 30kVp with a 0.5
Aluminium filter- brehmsstrahlung and 12keV L-shell
characteristic xrays.
• Molybdenum target with Mo/Rh filter is more suitable for
mammography.
• Rhodium target filtered with Rh filter gives a similar spectrum
as molybdenum.
• Since the atomic number is higher, the brehmsstrahlung
radiation is also higher than molybdenum.

11. FILAMENT
• Positioned within a focussing cup with two focal spot sizes.
• Filament types are either double wound/flat ribbon/ circular
filament.
• Focal spot size is very critical in mammography where high
spatial resolution is required.
• Small focal spot is used with small anode angle, which permits
the use of high mA factors.
• Usually the cathode is positioned towards the chest wall ,
which makes the patient positioning east and takes care of
the heel effect.

12. FILTERS
• Thin beryllium window or borosilicate glass window is used to
reduce inherent filtration, since it offers low attenuation.
• For a tungsten target x ray tube , Mo or Rh filter is
recommended.
• In case of rhodium target x ray tube , rhodium filter of 0.025
mm is used which gives high quality x rays with higher
penetration.
• Combination is suitable for thicker and dense breast imaging.

13. 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.
• Covered tiny details such as micro calcifications.
• Hence oscillating grids are used.
• Grid ratio of 4:1 or 5:1.
• The grid lines are eliminated by the motion of the grid.
• Grids improve the image quality.

15. 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 towards the chest wall and the
anode is towards 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.

17. Compression peddle
• Decreases the thickness of the breast, thus reduces the
scattered radiation- improves the contrast.
• Decreases the kinetic blur.
• Reduces the geometric unsharpness by homogenously
bringing the object close to the film.
• Makes the breast thickness uniform in film density.
• Differentiates the easily compressible cysts and fibroglandular
tissue from the more rigid carcinomas.
• Separates the super imposed breast lesions.
• Reduces radiation dose to the breast tissue.

18. • The compression device is
parallel to the receptor surface.
• Radiolucent plate that is flat
and parallel to the support
table.
• Should match the cassette size.

19. Automatic exposure control
• AEC system employs phototimers to measure the x ray
intensity and quality.
• Kept closer to the image receptor, to minimize the object to
image distance- improves spatial resolution.
Two types:
- Ionization chamber type.
- Solid state diode type.

20. SCREEN FILM SYSTEM
• The x ray film should have high resolution and small grain size
and used along with single intensifying screen
• The emulsion surface of the film must face the screen.
• Prevents loss of resolution due to light diffusion in the screen.
• Gadolinium oxysulifde activated with terbium is used
as screen phospor.

22. DOUBLE EMULSION TECHNIQUE

23. RADIOLOGICAL ANATOMY OF THE BREAST
• Schematically, the radiological
examination may show the
following normal anatomical
structures:
– Skin
– Nipple and areola
– Fatty tissue
– The breast tissue proper, or
corpus mammae
– Blood vessels

25. Mammography
• Overall breast density reflects ratio between glandular elements
(higher density) and fat (lower density); usually symmetric between
breasts.
• Fatty involution typically begins in lower-outer quadrant; progresses
with age to upper-outer quadrant
• American College of Radiology Breast Imaging and Reporting and
Database System (BI-RADS) density categories
A: Almost entirely fat
B: Scattered fibroglandular densities
C: Heterogeneously dense
D: Extremely dense

27. NIPPLE-AREOLA COMPLEX AND SKIN
• Normal skin thickness is usually < 2 mm
• Dermal papillae often visible as grooves in nipple
• Nipple usually everted
• Should be seen in profile on at least one of two standard
mammographic views
• New nipple inversion requires diligent search for subareolar
pathology, esp. if unilateral
Can be caused by periductal mastitis, esp. bilateral

28. Imaging Approaches
• Screening mammography
– CC and MLO views of each breast
– Additional views performed as
necessary to include all glandular
tissue
• Diagnostic mammography
– Examination is tailored to clinical
question,
– performed under direct supervision
of radiologist
– Any number of views are used to
answer the question
– • Is there a real abnormality?
– • If finding is real, what is the
morphology and level of suspicion
for cancer?
– Final assessment may require
additional modalities,
e.g., ultrasound or (rarely) MR
– Report should conclude with a Bl-
RADS final assessment and a
management recommendation
– Rare use of BI-RADS 0 if MR needed
due to inconclusive mammogram
and US, finding too vague to biopsy

29. Conventional Vs Digital Mammography
• Researches have proven that digital is superior to film for
women under the age of 50 and for women with dense
breasts.
• 25% less radiation to the patient
• Ease of storing, sharing and manipulating electronic images

30. Mammography
In digital mammography screen-film system has been
replaced by Detectors to give the digital images
Conventional

31. DIGITAL MAMMOGRAPHY
• The stages in digital imaging :
• Image capture by digital detector
• Conversion of latent image into digital data set
• Processing of image data
• Display of processed image
• Transmission and archival of data set

33. IMAGE ACQUISITION DEVICES
• CHARGE COUPLE DEVICE TECHNOLOGY
• Digital detectors consist of a
phosphor, which is optically
coupled to the CCD.
• ADVANTAGE- The slit
collimation of the X-ray beam
results in a significant
reduction in scatter.
• This eliminates the need for a
grid, leading to potential dose
savings .

34. SELENIUM-BASED DETECTORS
• Selenium based detectors consist of a thin layer of amorphous
selenium deposited on the imaging plate.
A uniform positive charge is built up on the surface of the selenium.
• When X-ray photons strike the surface of the selenium, electrons
are freed.
• This leads to a partial discharge of the uniform surface charge
pattern.
• The degree of discharge reflects the local radiation exposure,
leadingto a latent image in the form of a charge distribution
pattern.
• This charge pattern is then “read” and the resultant electrical signal
digitised.

35. ADVANTAGES OF DIGITAL
MAMMOGRAPHY
1. Acquired in less than a minute as compared to
conventional mammography .
2. Spot view digital systems are available to help
guide breast biopsy .
3. Superior contrast resolution especially in dense
breast tissues
4. Offers the possibility of three dimensional breast
tomography using relatively low doses .

36. MAMMOGRAPHY POSITIONING

37. Standard views:
45* Medio lateral Oblique (MLO view)/ Lundgren’s view
Craniocaudal view (CC view)
RCC RMLO
LCC LMLO
Left
Craniocaudal
Right
Craniocaudal
Right
Mediolateral
Oblique
Left
Mediolateral Oblique

38. Cranio caudal 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 x ray beam is directed vertically
from above.
• Postero medial aspect should also be included.

40. Mediolateral oblique 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
patients arm is abducted at the elbow by 80 degrees.
• The x ray beam enters the breast from the medial side-
compression is applied to the pectoralis major muscle.

42. LAT
Left Axillary Tail
LCV
Left Cleavage
LFB
Left From Below
LLMO
Left Lateromedial
Oblique
LML
Let Mediolateral
LRL
Left Roll Lateral
LRM
Left Roll Medial
LLM
Left Lateromedial

43. MAMMOGRAPHIC SIGNS
• The detection and identification of elementary mammographic signs form
the basis for correctly interpreting breast pathologies and describing them
accurately in the mammographic report.
• The specific features are the basis for classifying the lesions as either
benign or malignant. These features define the positive predictive value
(PPV)

44. Mammographic signs can be described in terms of:
– Opacity (mass)
– Architectural distortion
– Calcifications
– Radiolucency
– Asymmetry
– Focal asymmetry
– Skin thickening and retraction
– Oedema and trabecular thickening
– Asymmetrically dilated ducts

45. OPACITY
• Definition
– A space-occupying lesion visible in two projections, implying the
concept of mass and volume.
– An alteration visible in just one projection can be described as a
density or focal asymmetry.
• Shape: oval (may include 2 or 3 lobulations), round or
irregular
• Margins: circumscribed, obscured, microlobulated,
indistinct, spiculated
• Density: high, equal, low or fat-containing.

47. • The margin of a lesion can be:
• Circumscribed (historically well-defined).
This is a benign finding.
• Obscured or partially obscured, when the margin
is hidden by superimposed fibroglandular tissue.
• Microlobulated. This implies a suspicious finding.
• Indistinct (historically ill-defined).
This is also a suspicious finding.
• Spiculated with radiating lines from the mass is a
very suspicious finding.

49. • The density of a mass is related to the
expected attenuation of an equal volume of
fibroglandular tissue.
High density is associated with malignancy.
It is extremely rare for breast cancer to be low
density.

51. ARCHITECTURAL DISTORTION
• The term architectural distortion is used, when the
normal architecture is distorted with no definite mass
visible.
This includes thin straight lines or spiculations radiating
from a point, and focal retraction, distortion or
straightening at the edges of the parenchyma..
• Architectural distortion can also be seen as an
associated feature.
For instance if there is a mass that causes architectural
distortion, the likelihood of malignancy is greater than
in the case of a mass without distortion.
• Classification
– Marginal
– Intra-parenchymal distortion.

52. Notice the distortion of the normal breast architecture on oblique view
(yellow circle) and magnification view.

53. CALCIFICATIONS
• Definition
– Calcifications are amorphous, radiopaque, acellular entities produced by
calcium deposits.
– They reflect the secretory or degenerative processes of the breast.
Malignant calcifications may be caused either by cellular secretion or by
calcification of necrotic cancer cells.
– Calcifications are among the most frequent mammographic signs and can
also be amongst the most difficult to define and interpret.
• In relation to their site of origin, calcifications are classified as
– Intraductal
– Lobular
• Evaluation
– Shape
– Distribution
– Site
– Size
– Number

54. • Lobular calcifications: This results in uniform, homogeneous and sharply outlined
calcifications, that are often punctate or round.
When the acini become very large, as in cystic hyperplasia, 'milk of calcium' may fill these
cavities.
• Intraductal calcifications: form a complete cast of the ductal lumen.
This explains why they often have a fine linear or branching form and distribution.
Intraductal calcifications are suspicious of malignancy and are classified as BI-RADS 4 or 5.

55. DUCTAL CALCIFICATIONS

56. LOBAR CALCIFICATIONS

57. .

59. Suspicious morphology
• Amorphous (BI-RADS 4B)
So small and/or hazy in appearance that a more specific particle
shape cannot be determined.
• Coarse heterogeneous (BI-RADS 4B)
Irregular, conspicuous calcifications that are generally between 0,5
mm and 1 mm and tend to coalesce but are smaller than dystrophic
calcifications.
• Fine pleomorphic (BI-RADS 4C)
Usually more conspicuous than amorphous forms and are seen to
have discrete shapes, without fine linear and linear branching
forms, usually < 0,5 mm.
• Fine linear or fine-linear branching (BI-RADS 4C)
Thin, linear irregular calcifications, may be discontinuous,
occasionally branching forms can be seen, usually < 0,5 mm.

61. Distribution of calcifications
• The arrangement of calcifications, the distribution, is at least as
important as morphology.
These descriptors are arranged according to the risk of malignancy:
• Diffuse: distributed randomly throughout the breast.
• Regional: occupying a large portion of breast tissue > 2 cm greatest
dimension
• Grouped (historically cluster): few calcifications occupying a small
portion of breast tissue: lower limit 5 calcifications within 1 cm and
upper limit a larger number of calcifications within 2 cm.
• Linear: arranged in a line, which suggests deposits in a duct.
• Segmental: suggests deposits in a duct or ducts and their branches.

63. • Site: Before starting to analyse calcifications, it is
advisable to ascertain that calcifications are truly
intra-mammary, to rule out skin or
pseudocalcifications due to artifacts.
• Size: Many different dimensions are reported, but
calcifications associated with malignancies are
generally between 0.5 and 2 mm, though often even
smaller.
• Number: There is no consensus . The number of
calcifications must be evaluated together with their
morphology and distribution.

64. RADIOLUCENCY
• A sharp-edged radiolucent mass may be seen/ with a
radiopaque rim that is generally complete or only partly
broken. Varying in size and sometimes occupying the whole
breast.
• These may be round, oval or more rarely lobulated.
• They are usually caused by lipomas/ pseudolipomas and foci
of fat necrosis.

66. ASYMMETRIC BREAST TISSUE
• Significant areas of fibroglandular tissue on one side that
appear different compared with the contralateral breast,
because they are either of greater extent or of higher density.
If there are no other abnormalities, this is simply a normal
variant of breast structure.

67. FOCAL ASYMMETRY
• Areas of glandular tissue without the characteristics of a true mass,
but recognizable with similar appearance in the craniocaudal ,
lateral and oblique projection.
• These may simply be normal local asymmetries but further
investigation is justified, with targeted magnification views and if
necessary ultrasound.

68. SKIN THICKENING AND RETRACTION
• Skin thickening and retraction can be diffuse or focal. Skin
thickening or even ulceration can occur as a result of tumor
direct invasion or through thickening and retraction of
Coopers ligaments.
• Skin changes can result from a contiguous malignancy,
infection or inflammation, primary skin disorders, lymphatic
or vascular obstruction. and systemic diseases affecting the
skin.
• Post-surgical scarring and fat necrosis can also cause skin
thickening and retraction.

69. • A high density, stellate
opacity with radiating
spicules into the
surrounding parenchyma is
seen in the inner subareolar
location with thickened and
retracted overlying areolar
skin.

70. OEDEMA
• Diffuse oedema causes generalized thickening of the
trabecular stromal net. There may also be thickening of the
skin.
• This finding is typical of benign processes such as mastitis,
post-radiotherapy changes and congestive heart failure
secondary to kidney failure.
• Thickened skin also invariably accompanies inflammatory
carcinoma in which a focal opacity may be visible
mammographically.
• Post-therapy follow-up may be advisable in these cases to
permit a differential diagnosis.

71. ASYMMETRICALLY DILATED DUCTS
• Linear, ribbon-like, tubular or branching, single or multiple
opacities, parallel and radiating in the retroareolar space.
• This appearance is typical of ectactic ducts and, less
commonly, of intraductal papilloma or carcinoma.

72. BI-RADS - Breast Imaging Reporting and Data
System
• BI-RADS 0: Screening mammogram with finding for which
additional evaluation is needed
– Also known as recall or call-back
• BI-RADS 1: Negative mammogram
• Bl-RADS 2: Mammogram with a benign finding
• Bl-RADS 3: Mammogram with a probably benign
finding, for which short-interval follow-up suggested

73. • BI-RADS 4: Mammogram with a suspicious
abnormality for which biopsy should be considered
• BI-RADS 5: Mammogram with a finding highly
suggestive of malignancy, for which appropriate
action should be taken
• BI-RADS 6: Mammogram with a known
biopsy-proven malignancy, for which appropriate
action should be taken

76. Breast Ductography
• Helps define the cause of unilateral, single-
pore, spontaneous nipple discharge.
• Allows diagnosis of the underlying condition,
definition of the extent of disease,
identification of central and peripheral lesions,
and guidance of surgical excision.
• It involves cannulation of the discharging duct,
injecting contrast material within and
obtaining 90 degree and craniocaudal views.

77. Normal ductogram

78. In this patient, contrast outlines (single arrows) a duct that is wider than normal
(dilated), and the contrast column is disrupted by the presence of a tumor (double
arrow). About half of the patients presenting with spontaneous nipple discharge are
found to have papillomas, which are benign, non-cancerous tumors. The tiny, blunt-
tipped needle used to inject the contrast is seen at the edge of the film (wide arrow).

79. Breast tomosynthesis
• Modification of a digital mammography unit to enable
the acquisition of a three-dimensional (3D) volume of
thin-section data.
• Images are reconstructed in conventional orientations
by using reconstruction algorithms similar to those
used in computed tomography (CT).
• Reduces or eliminates tissue overlap.

80. In breast tomosynthesis, a moving x-ray source
and a digital detector are used.

81. • The X-ray tube makes an arc, during which is acquired a series
of images, each of which is delivered a dose equal to a
fraction of that provided in a standard mammogram. During
the acquisition any detector element receive in time
sequence related information on each object volume
element. The set of digital projections thus contains a
complete structural information on all the object layers in the
form of raw data

82. • Acquisitions may be performed either with the
step-and-shoot method or with a continuous
exposure method.
• The image data are sent from the acquisition
workstation to the reading workstation. Images
are reconstructed by using a mathematical
algorithm similar to those used in CT
reconstructions, to generate a set of thin image
sections parallel to the breast platform

84. • Tomosynthesis, therefore, does not provide direct projection
images, but reconstructed images of any individual layers
through several available algorithms, more or less efficient,
each aimed to removing from reconstructed slice the upper
and lower layers "structured noise".
• DBT allows the detection of a greater number of expansive
lesions and a better morphological analysis of masses and
architectural distortions, thanks to the contrast of findings
greater than the background, given by the more shade
structures belonging to the upper and lower layers, and then
to the smaller amount of noise. It is thus exceeded one of the
limits of two-dimensional imaging, which is the masking of
lesions caused by superimposition of normal structures.

85. • A further advantage of DBT is given by the lack of need for
operator training (the breast is positioned just like a
conventional mammography in MLO and / or CC projection)
and for the radiologist (as he continues to perform diagnosis
from images with mammograms features).

86. Comparison of screening mammography with breast tomosynthesis in a 57-year-old
woman. (a) Digital mammogram shows a mass (arrows) in the lower outer part of the
left breast. The mass is not clearly visible because of surrounding dense tissue. (b)
Breast tomosynthesis image provides clearer depiction of the mass (arrows), which is
well circumscribed.

87. Invasive ductal carcinoma in a 45-year-old woman with a lump in the left breast for 6
months. (a) Digital mammogram clearly shows an oval-shaped relatively well-
circumscribed primary mass. (b) Breast tomosynthesis image provides better
depiction of the microlobulated, spiculated border of the mass (arrows), a finding
suggestive of malignancy.

88. Computer-Aided Detection
• CAD programs are commercially available systems that use
computer software to assist the mammographer in detecting or
identifying potentially suspicious abnormalities on a mammogram.
• The CAD program identifies potential abnormalities on the images
and marks areas on the study that the computer considers to be
suspicious.
• The radiologist reviews the flagged areas to assure that nothing
was missed.
• DM readily provides images that can be used with CAD. Film screen
mammography has to be digitized in order for CAD to be
performed.

90. Bibliography
• Bi-RADS for Mammography and Ultrasound 2013 Updated version
Harmien Zonderland and Robin Smithuis
• Diagnostic Radiology: Musculoskeletal and Breast Imaging by Berry
Manorama, Chowdhury Veena, Mukhopadhyay Sima, and Suri Sudha