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Case Review & Image Case Review & Image CritiqueCritiqueCritiqueCritique

Olive Peart, M.S. R.T. (R)(M)www.opeart.com

West Physics Consulting is a proud supporter of MTMI’s Diagnostic Imaging Programs.

Thank you West Physics!

The Need for Dedicated The Need for Dedicated Mammography ImagingMammography Imaging

Breast is all soft tissue Similar mass densities Need to maximize d o a

contrast Need highest possible

resolution Need to keep radiation

doses low

Digital Mammography TubeDigital Mammography Tube

Electronic vacuum tube Two electrode

T t T t t A d ◦ Tungsten Target at Anode Single tracks more reliable and less expensiveMaximum anode heat loading of dual tracks are inferior to single tracks Single track tungsten tubes support 2-3 times the max anode load vs. dual track

◦ Cathode with filament

Inherent & Added Filtration Inherent & Added Filtration ◦Inherent:OilGlass or metal window of x-ray t btubeMirror assemblyCompression plate ◦Added:Rh/Ag/AlMo (analog)

Line Focus PrincipleLine Focus Principle

The line focus principle allows a large area of focal spot heating while keeping heating while keeping the effective focal spot small

Decreasing target angle = decreasing effective focal spot size

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Anode Heel EffectAnode Heel Effect SID 60-70 cm FOV 24 x 30cm

Reduce variation of du a a o ointensity due to heel effect

Cathode-anode orientation◦ Anode at nipple

HalfHalf--Field GeometryField Geometry Central axis of beam

parallel to chest wall 24x30cm FOV

requires mim. effective anode angle effective anode angle of 20-24˚(tube tilt + anode angle)◦ Typical 16˚anode angle

+ 6˚ tube tilt

Grids Grids

Improve contrast Decrease scattered

radiation Results in more radiation Results in more radiation

dose to patient◦ Always used in routine imaging◦Never used in magnification mammography or Tomo

Characteristic of the GridCharacteristic of the Grid Focused grid Grid ratio 3:1 to 5:1

– focused to the SID Grid frequency 30-50 q y

lines per cm Grid interspace

material◦ Carbon◦ Wood

High Transmission Cellular (HTC) GridHigh Transmission Cellular (HTC) Grid

Characteristics of a crossed-grid

Reduces scatter in two directions rather than one

Copper as the lead strip Air as the interspace

material Result in less radiation

to patient

Focal Spot Size Focal Spot Size

0.4 mm or smaller for routine work. The most commonly used is 0.3mm.

0.15 mm or smaller for magnification. The most common focal spot size in magnification is 0.1mm.

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Back Back Up Up TimersTimers

Needed to avoid gross overexposure Maximum back up time =◦ 600 mAs for grid techniques◦ 300 for non-grid workA id b k ti b i Avoid back-up timer by using higher kVp not higher mAs

The back up time will reach if an implant covers the majority of the detector

Automatic Exposure Control Automatic Exposure Control

Analog: The ionization chamber ◦ The AEC device is positioned below the IR to minimize OID

Digital: Amorphous selenium or Scintillation phosphors (e.g. Cesium iodide)◦ Entire image detector serves as the AEC devices

Exposure ModesExposure Modes

Manual – operator selects all parameters Auto-time – system selects mAs, operator

selects filter and kVA t kV t l t kV d A Auto-kV – system selects kV and mAs, operator selects filter

Auto-filter – system selects filter, kV and mAs

Input Input -- Patient InformationPatient Information Work list◦ Patient’s name selected from a list

IP scanner◦ Used with CMUsed with CM

Magnetic card swipe◦ Patient’s information on credit card-like device

Digital ImagingDigital Imaging

Latent image –formed on digital detector

ADC – sends signal from detector to computer

LCD (Display monitor)

Biggest AdvantageBiggest Advantage

Wide latitude Linear response

to the intensity of x ray of x-ray exposure

Optimization of contrast

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Exposure LatitudeExposure Latitude Range of exposures (under/over) that

can be used ◦ Analog receptors can produce an acceptable image within a range of 30% underexposure and 50% overexposureDi it l i i d t bl ◦ Digital imaging can produce an acceptable image at 50% underexposure and 100% overexposure

Digital can correct exposure factors over 100% times greater than or 50% less than normal range

Pre ProcessingPre Processing

Automatic Rescaling will correct Raw Data◦ Enhance contrast &

sharpness ◦ Corrects artifacts due to ◦ Corrects artifacts due to

bad detector elements◦ Applies processing

algorithms Generates a histogram

Other Advantages of DigitalOther Advantages of Digital Improve workflow by

reducing repeats Reduce cost

associated with associated with repeats

Reduction in lost films Every reprint is an

original◦ Medico legal risk reduced

Disadvantages of DigitalDisadvantages of Digital

Start-up cost Visual cues of over and under exposure

not easily seen◦Decrease contrast (over exposure)◦Decrease contrast (over exposure)◦Quantum noise (under exposure)

Loss of experience with manipulating technical factors and film processing

Loss of ability to control patient dose De-emphasize thinking of radiation

safety and patient protection

Other FearsOther Fears

Outsourcing of reports – eliminating the need for a radiologist at any one site

An insufficient backup system

The Digital ImageThe Digital Image

Digital is formed as a 2-dimensional (2-D) matrix of picture elements (pixels)

The matrix A box of cells ◦ The matrix–A box of cells with numeric values arranged in rows and columns

Each cell corresponds to a specific location in the image

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The Matrix SizeThe Matrix Size

Determined by the number of pixels in the rows and columns

Expressed by listing the Expressed by listing the number of pixels in each dimension (length and width)◦ Common sizes: 512 × 512 1024 × 1024

A PixelA Pixel

One individual cell in a matrix Pixels have bits of information◦ A single unit of data

i l bi di i ‘0’ ‘ ’ h◦ A single binary digit, ‘0’ or ‘1.’ The computer can use as many bits as necessary to express a decimal digit

What is a byte?◦ A bunch of 8 bits

Image ResolutionImage Resolution

Each digital image has between 25,000 and 1 million pixelsThe smaller the pixels, the greater the spatial resolutionspatial resolutionThe greater the number of pixels, the greater the image resolution

Spatial ResolutionSpatial Resolution The minimum separation between two

objects at which they can be distinguished as two separate objects in the image◦ In analog imaging spatial resolution~11 lp/mmg g g p p/◦ In CR ~ 2.55-5 lp/mm. DM~7 lp/mm

Dynamic range is higher in digital which increases contrast resolution ◦ More densities seen & gives the appearance of more detail

CNR & SNRCNR & SNR

Contrast –minimum density difference between two tissues that can be detected in the image as different densities.

SNR – measure of image noise◦ Increase SNR = decrease contrast

Dynamic Range & MTFDynamic Range & MTF Reflects the receptor’s ability to respond to

different exposure levels◦ Quantum mottle in CR if the exposure is 50% below

the ideal exposure p◦ Lower contrast in CR if the exposure is more than

200% of ideal exposure

Modulation Transfer Function – ability of the detector system to produce an image exactly as the object

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Window Level & WidthWindow Level & Width Window level controls

the brightness displayed ◦ Increase window level =

increase brightness Window width controls Window width controls

the ratio of black to white displayed therefore the contrast ◦ Increase window width =

decrease contrast

Brightness & ContrastBrightness & Contrast Image Brightness – controlled by the

processing software (not mAs) ◦ Brightness can be altered after the exposure.

Image contrast – controlled by processing f ( k )software (not kVp)

◦ Contrast can be altered after the exposure. Recorded Detail – controlled by the digital

acquisition i.e. pixel size and display matrix and the capabilities of the monitor

LCD MonitorsLCD Monitors Has DAC - Converts the

electronic signal from the computer to light (a visible image)M it l ti d d Monitor resolution depends on the pixel pitch ◦ the pixel pitch is the distance between cells of the same color

Post Processing Post Processing AWS allows rapid viewing of the image◦ Low resolution◦ Post processing of image

RWS for interpretation◦High resolution

Change Brightness/ContrastChange Brightness/Contrast Images Images -- Dense and Fatty BreastDense and Fatty Breast

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Imaging Calcifications or Spot Imaging Calcifications or Spot CompressionCompression

Inverting Image or Add Ruler or Inverting Image or Add Ruler or TextText

Image ZoomImage Zoom Other Post ProcessesOther Post Processes Noise reduction or suppression -

removes signals that do not provide useful image data

Edge enhancement , frequency processing or spatial frequency processing or spatial frequency filtering

Smoothing Background removal or shuttering

Storage OptionsStorage Options

Electronic image storage or archival in encoded form to reduce space◦ Short term – local storage gon the hard drive◦ Medium term – redundant array of independent disks

(RAID)◦ Long term – digital linear tapes, RAID or optical disk◦ Compressed storage

Image CompressionImage Compression

Required for teleradiography◦Lossy◦Lossless

Lossy is acceptable in general radiography but not acceptable for mammography

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Laser PrintingLaser Printing

Processing without chemicals

No drainage or water connection

Film can be handled under daylight conditions – no darkroom needed

Disadvantage Very expensive Optical density and latitudes lower

PACS & Teleradiography PACS & Teleradiography PACS – Picture Achieving and Communication

System◦ DICOM compatibility◦ Modality comparison

P i fil i◦ Prior film comparison Teleradiography – images can be transmitted

to distant locations e.g. Radiologist’s home◦ Virtual consultation◦ Internet access to images – via telephone, cable or

satellite

Understanding Digital QCUnderstanding Digital QC MQSAMQSA Mammography Quality Standards Act –

enacted October 27, 1992 Enforcement by FDA began in 1995 ◦ All mammography units must be: Accredited Certified Inspected

Certifying AgenciesCertifying Agencies

FDA or FDA approved certifying state The FDA will not certify facilities in

approved certifying states and certifying states can only certify certifying states can only certify facilities within their state borders

The FDA - approved certifying states are: Illinois, Iowa, South Carolina and Texas

Accreditation BodiesAccreditation Bodiesin USin US

American College of Radiology (ACR), States of Arkansas, Iowa and Texas

State accreditation bodies can accredit only those facilities that are located in their respective states

State accreditation bodies or FDA can only accredit specific FFDM models

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Quality Standard IncludeQuality Standard Include Regular quality control testing Mandatory initial qualifications for

mammographer, radiologist and physicistp y

Enforcing continuing education qualification for mammographer, radiologist and physicist

Regular inspection of mammography facilities

Key Components of the MQSA Key Components of the MQSA Certificate placement Consumer complaints mechanism Infection control Self referrals

Medical records Medical records Record keeping & transferring of

records (HIPAA) Communication of results to patient Assessment categories Medical audit Personnel requirements

Qualification & Qualification & DocumentationsDocumentations

There are 3 different initial requirements: Prior to 10/1/94 Between 10/1/94 & 4/28/99

After 4/28/99 After 4/28/99

Initial QualificationInitial Qualification--MammographerMammographer

After 4/28/99 Complete 27.5 hours mammography

course Complete 25 supervised exams (12.5hrs)◦ State specific i.e. State license

Board Certification (ARRT or ARCRT) 8-hours edu specific to digital 8- hours edu specific to DBT

BBenefits enefits of CQIof CQI

Reduction of unnecessary radiation to patient by reducing repeat

Improve overall efficiency of service

Improved patient satisfaction

Consistency of image production

Cost effectiveness

Analog Quality Control Analog Quality Control Mammograher Testing Duties

Daily tasksDarkroom cleanliness/ processor quality control

Weekly tasksViewbox and viewing conditions/phantom iimages

Monthly tasksVisual checklist

Quarterly tasksRepeat analysis/ analysis of fixer retention

Semiannual taskDarkroom fog testing/ screen-film contact/compression

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Digital Quality ControlDigital Quality Control

FFDM Computer

Mammography◦ Digital QC has ◦ Digital QC has manufacture specific quality control test

Digital Digital –– Summary QC TestSummary QC Test Daily

Monitor Cleaning Workstation viewing & Viewing Conditions

Weekly◦ Flat Field Test

◦ Brightness/non-uniformity/high frequency modulation (HFM)Brightness/non uniformity/high frequency modulation (HFM)◦ MTF & CNR measurement CNR –differentiate micro-cal from background

image MTF –Modulation Transfer Function: consistency of

CNR◦ Artifact Evaluation of Detector & Printer◦ (Hologic)–SMPTE & compression indicator Communication between AWS and detector/printer

◦ Phantom Image check

Digital Digital –– Summary QC TestSummary QC Test

Monthly AOP Mode and SNR Check◦ Automatic optimization of parameters◦ SNR – image obscured by random signal variations

Visual Check list Visual Check list Quarterly

Repeat Analysis Check Semi-annually

Compression Force Test

Clinical Image Evaluation Clinical Image Evaluation --DigitalDigital

◦ Positioning◦ Compression Exposure ContrastSh Sharpness Noise

◦ Artifacts Labeling

Clinical ImageClinical Image Facility’s best work – include 2 MLO/2 CC Reviewed/approved by supervising radiologist Must be “negative” images◦ BI-RADS 1 (“nothing to comment on…breasts are symmetrical…no masses, architectural y ,disturbances or suspicious calcifications”)◦ BI-RADS 2 (“benign”) with prior approval & report

Must not be from models or volunteers Entire breast must be imaged in a single

exposure on each projection.

RequirementsRequirements One dense case and one fatty case ◦ The clinical and phantom images from each unit must be taken within 30 days of each other and must be within the time period shown on the laser film printer QC chart shown on the laser film printer QC chart

All clinical images should be clearly dated

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Different Breast Densities (BIDifferent Breast Densities (BI--RADS)RADS)

FattyA. Fatty

breast

B. Scattered areas of fibroglandular

www.acr.org

densities

C. Hetero-genously

dense

Extremely dense

Dense

Never compress against a fixed margin or tissue

Movable margins of breastMovable margins of breast◦ Lateral and inferior margins

Fixed margins of the breast◦ Medial and superior margins

44--Projection Projection Routine ImagingRoutine Imaging

Craniocaudal (CC) of both breast

Mediolateral (MLO)of both breast(MLO)of both breast

Good CompressionGood Compression Breast should be

compressed until taut

Avoid compression against a fixed margin or tissue

Most movable margins are the lateral and inferior

Fixed margins are the medial and superior

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Key Point for the CCKey Point for the CC IP at elevated inframammary crease Ipsilateral arm down. Contralateral arm

raised - holding the machine for support Must include, within 1 cm, the same , ,

amount of tissue measured on the MLO Best demonstrates the anterior, central,

medial and posteromedial portions of breast – poorly visualize lateral breast tissue

Image Evaluation Image Evaluation --CCCC

Nipple in profile/centered Medial and lateral tissue

in the collimated field◦ Nipple centered

Pectoral muscle not always seen

CC should include within 1cm the PNL measurement of the MLO

Dense area adequately penetrate

Key Points for the MLOKey Points for the MLO Tube angulation will vary between 30 –

70 degrees depending of patient size i.e. Image plate parallel to muscle.

Arm closest to the breast being imaged, draped over the top of image plate.draped over the top of image plate.

The image plate in the armpit. Compression must support the anterior

breast tissue to preventing sagging & distortion of ductal architecture.

The pectoral muscles should be demonstrated to the level of nipple.

MLO Imaging MLO Imaging

MLO best demonstrates the extreme posterior and upper outer quadrant

Distortion of the anterior Distortion of the anterior, central and medial breast tissue

MLO positioningMLO positioning The more parallel

the image plate is to the pectoralis muscle the more tissue will be included in the image.

Source: ACR Manual 1999

Image Evaluation Image Evaluation -- MLOMLO

Pectoral muscle extend to or below the PNL

Inframammary fold open

Dense areas well penetrated

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Problem Imaging the MLOProblem Imaging the MLO

Drooping breast Abdominal tissue

superimposing the inframammary foldinframammary fold

Missing posterior breast

Imaging ImplantsImaging Implants

Routine 4-projection MLO and CC with limited compression

4 ID-projection series –MLO & CCM bilit i & f t Mobility, compression & exposure factors

depend on: Type of implantDegree of scarring and adhesion of theimplant to the chest wallBreast size and amount of actual tissue

EightEight--projection Seriesprojection Series

Standard projections demonstrates margins of the implantimplant◦ Manual technique may be necessary

EightEight--projection Seriesprojection Series

Modified (ID) projections demonstrate breast tissue◦Manual or AEC ◦Manual or AEC techniques depending on amount of breast tissue over the detector

ID TechniqueID Technique

Locate the extent of the implant

Have the patient step away from the unit

Place the IP just posterior to edge of posterior to edge of implant

Use thumb and finger to hold anterior breast

Compress. The edge of IP helps keep the implant back

Standard projection are inadequate Suspicious area seen on one projection

only Suspicious area needs work-up to avoid p p

the trauma of surgery

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90-degree mediolateral -ML

Lateromedial -LM L t di l

From Below - FB Cleavage - CV Axillary Tail – AT Superior-Inferior

Lateromedial oblique -LMO

Tangential - TAN Exaggerated craniocaudal –XCCL or XCCM

Supe o e oOblique - SIO

Positions◦ Rolled positions:◦ RM, RL & RS, RI◦ Magnification and

spot Ingenious!Ingenious!

In the normal anatomy the patient’s nipple does not fall in profile. What are your options?What are your options?

A. Image the entire breast first – using nipple marker. Separate imaging with nipple in profile - only if necessary

B. It is the normal anatomy. No added imaging necessary A

You are imaging an elderly patient with very thin breast. How do you eliminate the wrinkling?

A. Repeat. Push breast tissue posteriorly to remove wrinkling. Send repeat image

B. Leave wrinkling, do not repeat

C. Repeat. Push breast tissue posteriorly to remove wrinkling. Send both images

D. Use the XCCL projection C

How do you eliminate this skin fold in the axilla?

A. Smooth back the breast tissuetissue

B. Raise patient’s arm higher C. Lower patient’s armD. Additional imaging or

supplementary projections may be necessary

D

On this RCC the fold should be removed. What is its likely location?

A.On the mediolateral aspect of the breast

B.On the superior aspect of the breast

C.On the inferior aspect of the breast

D.On the lateral breast

C

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Why are mag view of the specimen recommended? Select the best answer…

A. To confirm the lesion was removed

B. To evaluate calcificationsC. To please the radiologistD. To please the patient

B

Case Case 66

Male patient came to the department because he felt bilateral breast lumps…

Give a possible cause.

A. CancerB. PapillomaC. FADD. Gynecomastia – right

greater than left D

Case Case 77

Above is the previous mammogram. To the right is the current. (Same patient).

What could have caused the change? HRT

Case Case 88 Your patient refused

compression and this was the result.

What is the recommended next step?

A. Image must be drepeated

B. No action needed–this was the patient’s choice

C. Ensure that the patient understands that that the mammo was suboptimal

D. A & C D

Case Case 99 Identify the

calcifications in the axilla region

A Possible DCISA. Possible DCISB. Oil cystsC. Deodorant

calcificationsD. Micro hematomas

C

Case Case 1010 What is the

‘Triangular Marker’ used to indicate?

A Nonpalpable lumpA. Nonpalpable lump

B. Skin lesion

C. Palpable lump

D. Surgical scars

C

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You noticed a lesion in the posterior aspect of the right breast.

What do you think What do you think the radiologist will suggest as the next image?

A. Repeat MLOB. Spot compression /mag C. XCCLD. Magnification onlyB

Case Case 12 12 What problem is

demonstrated here?

Nipple not Nipple not centered & not in profile

Clipping of medial breast

Case Case 1313

What problems are demonstrated here?

Closed IFClosed IF

Nipple not in profile

Not enough pec muscle

Case Case 1414 Identify the problem

•Medial Breast overlap

Case Case 15 15

What is obscuring the axillary breast tissue?

What other problem?

ArmNo open IF seenDrooping anteriorSkin fold in axilla

Case Case 1616

What problem is demonstrated here?

Tissue overlap on pmedial breast

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Identify the projection

CleavageCleavage

Identify the projection

AT

Identify the projection

90 ML90 ML

Identify the projection & problem

ML – 90ML 90

Clip IF

Identify the projection

XCCL

This artifact appeared during a needle localization. Identify the artifact…

•Patient gown

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Case 23 Which area of

breast tissue is missing◦ A. medial◦ B. lateral◦C. anterior◦D. posterior

lateral

Case 24

Identify the pathology and problem

Dimpling

No open IF

Case 25

Identify a possible cause of the problem

Finger

Skin fold cause by past lumpectomy

Case 26 What is the main

reason for the closed IF here?

Fold of skin

Quiz ShowQuiz ShowQuiz ShowQuiz Show

The tail of Spence is easily The tail of Spence is easily visualized using the AT projectionvisualized using the AT projection

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What area of the breast is best What area of the breast is best imaged using the Cleavage?imaged using the Cleavage?

Which projection is often used to Which projection is often used to prove “teacup” benign calcificationprove “teacup” benign calcification

Note: The ML cannot be Note: The ML cannot be used to replace the MLO

When imaging the kyphotic patient, When imaging the kyphotic patient, instead of the CC we could use the… instead of the CC we could use the…

When using magnification, the skin When using magnification, the skin dose is much higher than routine dose is much higher than routine imaging.imaging.

Spot compression can be Spot compression can be performed in any projection.performed in any projection. The true reverse of the MLO is the The true reverse of the MLO is the

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The XCCL projection is used to image The XCCL projection is used to image the extreme lateral aspect of the breast the extreme lateral aspect of the breast with the patient positioned CC with the patient positioned CC

Which positions can be used to Which positions can be used to remove superimposed tissue remove superimposed tissue

Rolled Lateral (RL)Rolled Lateral (RL)Rolled Medial (RM)

Rolled Superior (RS)Rolled Inferior (RI)

In additional to the CC & MLO which In additional to the CC & MLO which projections is often utilized when projections is often utilized when imaging the lumpectomy patient.imaging the lumpectomy patient.

The LM can be used to improve The LM can be used to improve details of medial lesions.details of medial lesions.

When imaging the male breast, on which When imaging the male breast, on which projection would chest hair present a projection would chest hair present a problem?problem?

The TAN projection can be used The TAN projection can be used to locate skin calcifications.to locate skin calcifications.

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The SuperiorThe Superior--inferior Oblique (SIO) inferior Oblique (SIO) directs the beam from the…directs the beam from the…

Inferior lateral to the inferior medial aspect of the breast

Superior lateral to the superior medial aspect of the breast

None of the above

Lateral to the inferior medial aspect of the breast

Superior lateral to the inferior medial aspect of the breast

Match the following associations:Match the following associations:

Magnification

Lumpectomy imaging

Spatula

Depressed sternum

Pectus excavatum

Large breast

Small breast

Microcalcifications

Skin folds

Sectional Imaging

Questions???

Thank You!Thank You!