Mammography basics Instrument Views Birads

1. MAMMOGRAPHY
DR. BRIBIN BRIGHT

2. MAMMOGRAPHY - INDICATIONS
 Screening of asymptomatic women.
 Screening of high risk women.
 Follow up of patients after mastectomy of same and opposite breast / same breast with implant
 Investigations of benign breast diseases with eczematous skin,nipple discharge , skin thickening .
 Investigation of a breast lump.
 Investigation of occult primary with secondaries .
 Male breast evaluation .

3. TYPE OF MAMMOGRAPHIC EXAMINATION
 Diagnostic mammography
Is performed on patients with symptoms or elevated risk factors.
Two or three views of each breast may be required.
 Screening mammography
Is performed on asymptomatic women with the use of a two view protocol,
usually medial lateral oblique and cranio caudal , to detect on unsuspected cancer

4. MAMMOGRAPHY - BASICS
 Uses low-energy x-rays (40kVp) for dectecting breast pathologies.
 Higher kV - Poor Contrast
Lower kV - Good Contrast
 Tissues within breast have very small difference in attenuation property - Lacks contrast
 <40kVp - Good photoelectric effect - brings out contrast between the tissues within the breasts.
 Better contrast
Better detailing of structures

5. INSTRUMENTATIONS
 HIGH FREQUENCY X-RAY GENERATOR
 X-RAYTUBE
 ANODE
 CATHODE
 BEAM PORT
 K-EDGE FILTERS
 COMPRESSION PADDLE
 SPOT COMPRESSION
 PARALLEL LINEAR GRID
 IMAGE RECEPTOR
 AEC (AUTOMATIC EXPOSURE CONTROL)

6. X-RAY TUBE
 Rotating Anode type
- Glass or Metal ceramic
Advantage
-Decreases off focus radiation
-IncreasesTube lighting
 Cathode - Dual focalspots
0.3mm (Imaging)
0.1 mm (Magnification)
( Focal spot - Penumbra - Resolution)
Helps identifiying microcalcification

7. ANODE (TARGET)
Usually-Tungsten (xray /Floro/ CT/ cathlab)
 MOLYBDENUM -17.5 & 19.6 keV
 RHODIUM -20.2 & 22.7 keV
 CHARACTERISTIC RADIATION
Characteristic x-ray Characteristic x-rays are produced after ionization of a k- shell electron.When an outer-shell
electron fills the vacancy in the k shell, an x-ray is emitted.
In mammography,17.5- 19.5kev characteristic x-ray is produced with Mo and 23kev is produced with Rh

9.  ANODE ANGLE = 16° to 0 to -9°
 EFFECTIVE ANODE ANGLE
- Angle of anode relative to the horizontal tube mount
 XRAYTUBE TILT
-To reduce unwanted radiation
- focus only to the breast area

10.  SOURCETO IMAGE DISTANCE (SID)
- lesser than usual Radiography -60/65 cm (Chest = 18)
- short SID
- Heel Effect utilized
 At Cathode → chestwall – Thicker tissues
SIDE
 At Anode → Nipple region – LessThickness
SIDE
Non-uniformity of X-ray Intensity
Along the cathode side - More Intensity
Along the Anode side - Less Intensity

11. PARTS OF MAMMOGRAPHY EQUIPMENT
 Beam port - 1 mm Beryllium
Since metal/ Glass is used in XRAYTUBE
metal will absorb the low energy photons from xray tube
 K-edge filters - Cuts unwanted Low energy photons (RADIATION)
/ High energy photons (SCATTER – Reduces contrast)
(0.03mm Mo / 0.025mm Rh)

12. PARTS OF MAMMOGRAPHY EQUIPMENT
To decrease Breast thickness, spreads out the tissue
- Spreads out superimposed anatomy.
 Scatter Radiation - contrast
 Radiation dose to the breast tissue
 Geometric Blurring (closer to image receptor )
 Decreases the kinetic blur .
 Makes breast thickness uniform in film density.
 Differentiates the easily compressible cysts and fibro-
glandular tissue from the more rigid carcinomas
 Separates the super imposed breast lesions .
Compression paddle

13. PARTS OF MAMMOGRAPHY EQUIPMENT
 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 microcalcifications
 Hence oscillating grids are used o Grid ratio of 4 :1 or 5 : 1
 The grid lines are eliminated by the motion of the grid .
 Grids improve the image quality and cause a significant reduction

14. PARTS OF MAMMOGRAPHY EQUIPMENT
 Spot.compression - for imaging particular region
 Parallel Linear grid - (4:1 to 5:1) low grade ratio grids used
to increase the Contrast
 Image Receptor
Screen film
CR Cassette
Flat panel detector - (Digital Mammography)
 AEC -Automatic Exposure Control
KeV selected → MAS automatically chosen.

15. FLAT PANEL DETECTORS - INDIRECT
Indirect Amorphous silicon technology
 Xray scintillator (Gradoliniun Sulphate / Csl)
Produces light flashes when Xray beam falls over it.
 Silicon Photodiode array (Photo detector)
Made of Amorphous silicon
Converts light photons from the scintillator into electrical signal
 TFT-electronic switch
- Reads electrical signal
- Gives positional information
-This data is sent to AEC (Analogue to Digital Converter)
 AEC
Converts it into digital signal and are finally sent to Computer for processing
 Disadvantage - LIGHT SCATTER
Scattering of light within the phosphors leading to unsharpness

16. FLAT PANEL DETECTORS - DIRECT
 Crystals of amorphous selenium
directly converts Xrays into electrical signal that is stored in a capacitor (ready to be read)

17. MAGNIFICATION TECHNIQUE
 To increase the visibility of finer details like microcalcification
Increase O ID - object to Image Distance
Breast is kept over a raised platform
No need for grid as there is presence of air gap

18. SCREEN FILM MAMMOGRAPHY
 Old method
 The image is created directly on a film-Non modifiable
 Less sensitive for women with dense breasts
 Screen film cassette used
Single emulsion film
Single screen
Terbium activated Gadolinium oxysulphide
Screen emits green light
Film will be sensitive to greenlight (ORTHOCHROMATIC FILM)

19. COMPUTER RADIOGRAPHY (CR) MAMMOGRAPHY
 A/K/A Filmless radiography
Electronic radiography
Digital storage phosphor imaging
 Xray images are acquired in digital format
 Photostimulable phosphor plates used
 Imaging plate has high sensitivity to xrays
 COMPONENTS
 storage phosphor cassette
 Storage phosphor reader
 Bar code scanner
 Workstation
Photostimuliable Phosphor (PSP) Cassette
PSP Receptor materials
. BaFBr : Eu2+
. BaF (Br1): Eu 2+
.Ba SrFBr:Eu 2+

20. DIGITAL MAMMOGRAPHY
 Also called full-field digital mammography (FFDM)
-in which the x-ray film is replaced by electronics that convert x-rays into mammographic pictures of the breast.
Display Monitor - HIGH RESOLUTION (5 MP)
 Direct Digital Mammography
- Flat panel detector with amorphous selenium array
 Indirect Digital Mammography
-Flat panel scintillator with amorphous silicon diode array

21. DIGITAL MAMMOGRAPHY
 ADVANTAGE
Better contrast,more details.Better delineation of parenchyma & subcutaneous tissue
Better noise level reduction
Tolerance to over/under exposure (Avoids Repetition?
Post-processing techniques for better diagnosis
Radiation dose is decreased- Mean glandular dose in mammography
Screen Film (2-3m bGy)
Digital (20-30% reduction)
Image can be seen quickly and stored digitally(less storage space )

22. LIMITATIONS OF 2D MAMMOGRAPHY
 20% of cancers will be missed
 10% recalled for additional workup
 75-80% of biopsies result in benign lesions
 sensitivity decreases with increased breast density
 2D mammograms,take images only from the front and side, this may create images with
overlapping breast tissue

23. ADVANCES IN DIGITAL MAMMOGRAPHY
 Computer -Aided Diagnosis
- uses software to detect area of clinical significance and highlight them for better output image
 Digital BreastTomosynthesis (DBT)
XrayTube rotates /moves in a 50-55° arc around the breast,
capturing several (11-25) low dose projections of the breast at different angles.
Then reconstructed to 3D Projection images (1 mm slices)
3D MAMMOGRAPHY

24. DIGITAL BREAST TOMOSYNTHESIS - DBT (3D MAMMOGRAPHY )
Disadvantages of DBT
• Twice the radiation compared to 2D mammo
• More storage requirements
• Takes longer time to read
• Cannot be read on demand
Advantages of DBT
• Increased cancer detection rate
• Lesions are better defined
• Precise location of lesions
• Less false positive recalls
3D MAMMOGRAPHY

25. HOW MAMMOGRAM IS PERFORMED ?

26. HOW MAMMOGRAM IS PERFORMED ?
 CRANIO CAUDAL (CCVIEW)
demonstrate maximum tissue on both medial and lateral
aspects of the breast with the retromammaryspace and some
pectoral muscle
The following points were analyzed on CC view:
 nipple should be in profile
 nipple should point straight and should not be pointing lateral
or medial
 PND (pectoral nipple distance) must be within 1 cm of the
same measurement of the MLO view.

27. HOW MAMMOGRAM IS PERFORMED ?
 MEDIOLATERAL OBLIQUE(MLOVIEW)
demonstrate axilla,axillary tail,and inframammary
fold with all the breast tissue
The following points were analyzed on MLO view:
 Breast should be pulled out with nipple in profile
 The pectoralis muscle margin should be well visualized
 The lower edge of pectoralis muscle should be at the level
of pectoralis–nipple line (PNL) or below
 PND must be within 1 cm of the same measurement of
the MLO view.
 When MLO image of both breasts are viewed as mirror
images,pectoralis muscle should meet in the midline and
form a “V”.

28. OTHER VIEWS
 Latero-medial (LO) - from the outside towards the center
 Medio-lateral (ML) - from the center towards the outside
 Spot compression - compression on only a small area,to get more detail
 Cleavage view - both breast compressed,to see tissue near the center of
the chest
 Magnification -to see borders of structures and calcifications

30. REPORTING A MAMMOGRAM
 Breast Imaging Reporting and Data System (BI-RADS)
RISKASSESSMENT AND QUALITYASSURANCETOOL developed byAmerican college of radiology (ACR)
that provides a widely accepted lexicon and reporting schema for imaging of the breast.
All mammographic, ultrasound and breast MRI findings and reports should closely adhere to the BI-RADS lexicon
and assessment categories.

33. THANKYOU