R2 ImageChecker D CAD User manual

User Manual

Software Versions 8.1– 8.3

PN 14375 Rev 001

Mammography

ImageChecker® D CAD Server

User Manual

Software Versions 8.1– 8.3

PN 14375 Rev 001

Technical Support

For support in North America contact:

Toll Free: +1 866.243.2533 (866.CHECKED)
Email: [e-mail]
Hours: Monday – Friday, 6:00 AM – 5:00 PM, PT (GMT –8:00)
Website: www.r2tech.com

For support in Europe, South America, or Asia, contact your local dealer or distributor.

© 2006, Hologic Inc. All rights reserved. Duplication or distribution without written permission is
prohibited. Hologic reserves the right to revise this manual. Issued October 2006.

Protected by one or more of the following U.S. Patents: 4907156, 5133020, 5452367, 5491627,
5537485, 5622171, 5657362, 5673332, 5729620, 5732697, 5740268, 5815591, 5828774,
5832103, 5917929, 6014452, 6035056, 6075879, 6078680, 6185320, 6198838, 6263092,
6266435, 6301378, 6404908, 6434262, 6477262, 6574357, 6580818, 6640001, 6628815,
6909795, 7054473, 7072498

Citra, Earlier. Smarter. Better., EmphaSize, Gold Standard CAD, Hologic, the Hologic logo,
ImageChecker, LORAD, Malc, PeerView, R2, R2 Technology, the R2 Logo, and Selenia are
trademarks or registered trademarks of Hologic in the USA. Embrace is a trademark of the Agfa­Gevaert Group in the USA. ClearView is a trademark of Fujifilm. Senographe is a registered
trademark of GE Medical Systems in the USA. MAMMOMAT is a registered trademark of
Siemens Medical Solutions in the USA.

Hologic Inc.
35 Crosby Drive
Bedford, MA 01730-1401 USA
Tel: [phone]
Sales: +1.781.999.7453
Fax: [phone]

www.hologic.com

Asia Pacific
Room 302, Hung Kei Building
5-8 Queen Victoria Street
Central, Hong Kong
Tel: [phone]

Hologic N.V.
Authorized Representative
Leuvensesteenweg 250A
1800 Vilvoorde, Belgium
Tel: [phone]
Fax: [phone]

MergeCOM-3 Advanced Integrator’s
Tool Kit is a product of Merge
Healthcare.

ii ImageChecker D v8.1–8.3 User Manual – PN 14375 Rev 001

Contents

Part 1: Introduction....................................................... 1

1.1. Intended Use......................................................... 1

1.2. Available Resources ................................................... 1

1.3. Warnings and Cautions ................................................ 2

Part 2: System Description ............................................... 7

Radiological Interpretation .............................................. 2

System Operation ..................................................... 3

Installation and Maintenance ............................................ 4

Symbols Used ........................................................ 5

2.1. Overview ........................................................... 7

2.2. CAD with ImageChecker D .............................................. 8

2.3. Benefits of CAD....................................................... 8

2.4. Clinical Workflow ..................................................... 9

2.5. System Features ..................................................... 10

ImageChecker CAD Algorithm .......................................... 10

Advanced License Features ............................................. 10

2.6. DICOM Connectivity .................................................. 11

Supported Views and Image Specifications ................................. 11

Supported Workstation Vendors......................................... 12

Archiving CAD Marks................................................. 12

CAD Results Formats ................................................. 13

Other Outputs....................................................... 13

System Data Flow .................................................... 14

Part 3: System Operation ................................................ 17

3.1. General Usage Guidelines ............................................. 17

3.2. Displaying CAD Results ............................................... 18

3.3. Printing Results and Reports ........................................... 19

Printing CAD Results ................................................. 19

Printing a Reimbursement Report........................................ 20

3.4. System Shutdown and Startup ......................................... 21

ImageChecker D v8.1–8.3 User Manual – PN 14375 Rev 001 iii

Contents

Shutting Down the System ............................................. 21

Restarting the System ................................................. 22

3.5. Using Queue Manager ................................................ 23

Part 4: Algorithm Description

4.1. ImageChecker CAD Algorithm .......................................... 25

4.2. ImageChecker CAD Marks ............................................. 26

4.3. EmphaSize (Variable-Size) Marks........................................ 27

4.4. PeerView Digital ..................................................... 28

4.5. What the Algorithm Marks............................................. 29

............................................ 25

Calcifications........................................................ 29

Masses/Architectural Distortions......................................... 30

4.6. Detecting Calcifications ............................................... 32

4.7. Detecting Masses .................................................... 34

4.8. Operating Points ..................................................... 36

Part 5: Index............................................................. 39

iv ImageChecker D v8.1–8.3 User Manual – PN 14375 Rev 001

Part 1: Introduction

f 1.1. Intended Use
f

1.2. Available Resources

f

1.3. Warnings and Cautions

The ImageChecker D CAD Server uses R2 Technology’s Gold-Standard CAD
(computer-aided detection) software to analyze mammography images. The CAD
results, when viewed with mammography images on a workstation, are used to assist
in the detection of regions of the breast that may be cancerous. The system is not a
diagnostic device; radiologists can interpret only original mammograms.

1.1. Intended Use

The ImageChecker system is a computer system intended to identify and mark
regions of interest on routine screening and diagnostic mammograms to bring them
to the attention of the radiologist after the initial reading has been completed. Thus,
the system assists the radiologist in minimizing observational oversights by
identifying areas on the original mammogram that may warrant a second review.

1.2. Available Resources

The following resources are available when working with ImageChecker D.

•

Technical Support and Service: For contact information, see ‘Technical Support’

on the back of the title page of this manual.

•

User Manual: This user manual describes the use of ImageChecker D in a simple,

streamlined format. You can purchase additional copies of the user manual
through your R2 Technology Account Manager.

•

Customer Bulletins: R2 Technology is committed to making our products safe and

easy to use. If an issue arises or new features become available, you will receive a
Customer Bulletin.

•

Training: The R2 Technology Applications team is available to train your staff,

should you feel they need additional training. Contact your R2 Technology
Account Manager if you want personalized instruction.

 Note: If you purchased the ImageChecker D system directly from an FFDM

manufacturer or distributor, your technical support and training will be provided by them.

ImageChecker D v8.1–8.3 User Manual – PN 14375 Rev 001 1

Part 1: Introduction

1.3. Warnings and Cautions

Radiological Interpretation

• The radiologist should base interpretation only on the original images and not

depend on the CAD marks for interpretation.



• The device is a detection aid, not an interpretative aid. The CAD marks should be

activated only after the first reading.

• The device does not enhance what the user sees, rather it helps to identify regions

on mammograms that should be re-examined.

• The device marks calcification features with triangles (Calc marks) and mass

features with asterisks (Mass marks). Where mass and calcification features
overlap within a specified distance (10-mm default), the device marks overlapping
features with pointed crosses (Malc marks). These features may not represent
cancer, and the skill of the user is still required for proper interpretation of areas
marked by the device.

• EmphaSize (variable-size) marks – Some sites may choose to display prominence

detail, in which case the size of a Calc, Mass, or Malc mark is proportional to the
ranking of the feature by the algorithm. The marked features may not represent
cancer, and the skill of the user is still required for proper interpretation of areas
marked by the device. For more information, see ‘

Marks

’.

4.3. EmphaSize (Variable-Size)

• During routine interpretation of mammograms and CAD marks created by

ImageChecker D, R2 Technology recommends use of a mammography
workstation that has been FDA-approved, recently calibrated, and employs a CAD
marking schema authorized by R2 Technology.

• The use of digitized images (scanned film images) for primary reading has not

been approved by MQSA. Digitized film images retrieved from archive should be
used only for the purpose of comparison with digital images meeting the current
standard.

• The device does not identify all areas that are suspicious for cancer.

– Some lesions are not marked by the device and a user should not be dissuaded
from working up a finding if the device fails to mark that site.

– The device is not designed to detect changes from other mammograms.

– The device is not designed to detect skin thickening or nipple retractions.

– Conditions of the breast that diminish mammographic sensitivity, such as
density of normal tissue, also diminish the sensitivity of the device.

– The device is more sensitive for detection of calcifications than masses, and the
sensitivity depends on the site-specific operating points chosen. For sensitivity
values, see ‘
algorithm has a lower sensitivity for masses greater than 2.5 cm in diameter.

4.8. Operating Points’. In addition to not marking all masses, the

– Individual practice patterns may influence results obtained when using this
device. Therefore, each facility and radiologist should carefully monitor the results

2 ImageChecker D v8.1–8.3 User Manual – PN 14375 Rev 001

1.3. Warnings and Cautions

that this device has on their practice of mammography in order to optimize its
effectiveness.

• Safety and effectiveness have not been established for analyzing mammograms

from patients with breast implants. For patients with breast implants, only
Implant-Displaced Views can be processed by the system and only in cases with a
maximum of 2.5 cm (1 in) of the breast implant appearing on the image.

• The performance of the system has not been characterized for special diagnostic

views (e.g., magnified views or spot-compressed views). Process only full-view
diagnostic images.

• The performance of the system has not been characterized for segmented views of

the breast (e.g., ‘mosaic’ views) where there is not a clear breast border. Process
only views with breast borders.

• Superolateral to Inferomedial Oblique (SIO) and From Below (FB) views are not

supported by ImageChecker systems when using the GE Radiotherapy Structure
Set (RTSS) CAD format. These views will be processed, but the results will be
flipped for the Right FB, Left FB, and Left SIO views, and so should not be used for
the SIO and FB views when using the GE RTSS CAD format.

System Operation

• Operators should review this manual and receive training before using the system.



• Use the system only outside the patient environment. The system is rated for use

only in an office environment.

• For proper system operation, the technical quality of the original films or images

(e.g., contrast) should meet relevant MQSA standards or the appropriate national
standards and be acceptable to the mammographer.

• The symbol next to the power connector indicates a potential shock hazard. To

reduce the likelihood of electrical shock or fire hazard, connect the computer only
to a power receptacle that is properly grounded and provides voltage and current
within the specifications of the system.

• There is a small risk of electrostatic discharge (static electricity). It is mostly a

nuisance and not likely to cause harm. However, a shock can cause accidental
injury, if, for example, you suddenly withdraw your arm and hit it against
something. To minimize possibility of shock, maintain greater than 40% relative
humidity, use shoes with natural-material soles, place equipment on nonpolymer
floors such as concrete, wood or floors treated with static dissipative, and/or
routinely touch metal with a metal object, such as a key, to painlessly discharge the
charge from your body.

• Do not place liquid containers on the device. In the event of a spill, shut down

power to all components prior to cleaning to minimize the possibility of electrical
shock. If internal components are exposed to liquid, do not operate the device –
contact your service representative.

• Always shut down the computer according to the procedures provided in this

manual. Improper system shutdown can cause loss of data or damage to the
computer operating system.

ImageChecker D v8.1–8.3 User Manual – PN 14375 Rev 001 3

Part 1: Introduction

• The device design and mode of operation are consistent with current standard

mammography clinical practices, as governed by the requirements of the
Mammography Quality Standards Act (MQSA) of 1992. Users are advised to
comply with the MQSA for the United States, or the appropriate national
standards, when implementing the ImageChecker Mammography System in
clinical protocols.

• This equipment has been tested and found to comply with the limits for a Class A

digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to
provide reasonable protection against harmful interference when the equipment is
operated in a commercial environment. This equipment generates, uses, and can
radiate radio frequency energy and, if not installed and used in accordance with
the instruction manual, may cause harmful interference to radio communications.
Operation of this equipment in a residential area is likely to cause harmful
interference, in which case the user will be required to correct the interference at
her or his own expense.

Installation and Maintenance

This product contains no user-serviceable parts. To prevent damage to the system:



• Maintain equipment in a well-ventilated, air-conditioned environment.

• Do not install or repair the ImageChecker D system. Only trained personnel,

authorized by R2 Technology, are qualified to install or repair the system.

• Disconnect power cord before moving or servicing.

• Before cleaning the computer, always shut down the system according to the

shutdown procedures in this manual and disconnect the power cord to prevent the
possibility of electrical shock. Never use alcohol, benzene, thinner, or other
flammable cleaning agents.

• Never use a two-prong adapter or extension cord to connect primary power to the

system. Use of a two-prong adapter disconnects the utility ground and creates a
severe shock hazard.

For service training, contact your technical service representative or call
R2 Technology Technical Support (see ‘
page of this manual).

Technical Support’ on the back of the title

4 ImageChecker D v8.1–8.3 User Manual – PN 14375 Rev 001

Symbols Used

The following internationally recognized symbols may be used in this manual and on
the ImageChecker products.

1.3. Warnings and Cautions

Type B Equipment Off

OnDangerous Voltage

StandbyFuse

Alternating CurrentProtective Earth Ground

Attention: Consult accompanying documents, or
pay special attention to the note next to the symbol.

Common Symbols

ImageChecker D v8.1–8.3 User Manual – PN 14375 Rev 001 5

Part 1: Introduction

6 ImageChecker D v8.1–8.3 User Manual – PN 14375 Rev 001

Part 2: System Description

f 2.1. Overview
f

2.2. CAD with ImageChecker D

f

2.3. Benefits of CAD

f

2.4. Clinical Workflow

f

2.5. System Features

f

2.6. DICOM Connectivity

2.1. Overview

The ImageChecker Mammography System is the first FDA-approved computer-aided
detection (CAD) system for full-view diagnostic and screening mammograms.
ImageChecker D is a server computer equipped with software that identifies and
marks regions of interest on routine diagnostic and screening mammograms that may
warrant a second review by the radiologist. Its purpose is to help minimize
observational oversights.

After the radiologist completes the initial reading of the mammogram, he or she views
the regions of interest marked on the images, and then returns to the original
mammogram for additional review if necessary.

Note that ImageChecker D is not a diagnostic device. Radiologists should base their
interpretation only on the original mammogram images.

ImageChecker D v8.1–8.3 User Manual – PN 14375 Rev 001 7

Part 2: System Description

2.2. CAD with ImageChecker D

The ImageChecker D system is a CAD server equipped with software that analyzes
images. The system accepts images from a digital mammography device or archive,
and then analyzes the images using a proprietary algorithm (i.e., a set of criteria) that
identifies regions of interest. These regions include:

• Clusters of bright spots, which are regions suggestive of calcification clusters

• Dense regions with or without radiating lines, which are regions suggestive of

masses or architectural distortions

ImageChecker D generates CAD marks identifying the regions of interest, and sends
the marks for display on a digital review workstation. The system can also send the
digital images and results to an archive system.

The original digital mammograms for a specific case are displayed on the workstation
for review by the radiologist. After making an initial interpretation from the original
mammograms, the radiologist displays the CAD marks and chooses whether or not to
reinspect the marked regions on the original mammogram.

The ImageChecker algorithm marks certain regions based on their image
characteristics. The system marks visually perceptible structures that have some of the
generally accepted geometric characteristics of calcifications or masses. The marked
areas may be something other than an actual abnormality, but the radiologist
generally recognizes that upon a second review of the original mammogram.

For more information about the CAD marks and the ImageChecker algorithm, see
‘

Part 4: Algorithm Description’.

2.3. Benefits of CAD

The interpretation of mammograms is challenging. Normal breast tissue varies widely
among women, even for the same woman over time or at different times of the
month. The radiologist also has to balance the need for accurate detection with the
need to limit the number of unnecessary procedures. The combination of viewing a
large number of cases, radiologist fatigue, the complex image of the breast structure,
and the subtle nature of certain observable characteristics of the disease can result in
false-negative readings. Studies show that half of undetected cancers are missed due
to observational oversights. The prevalence of observational oversights is not strongly
related to experience and may be inevitable with human observers.

The ImageChecker Mammography System is like a spellchecker for medical images. It
is designed to help radiologists in reducing the number of false-negative readings due
to observational oversight by drawing their attention to areas that may warrant a
second review.

Retrospective clinical studies using the film-based ImageChecker CAD algorithm have
shown that use of the ImageChecker system could result in earlier detection of up to
23% of the cancers currently detected with screening mammography in those women
who had a prior screening mammogram 9–24 months earlier. Early detection is the
key to higher survival rates, better prognosis and lower treatment costs.

8 ImageChecker D v8.1–8.3 User Manual – PN 14375 Rev 001

2.4. Clinical Workflow

The ImageChecker D system uses a high-performance computer that can be located
in any non-patient environment, provided it is connected to the mammography
network. The computer is a CAD server that that receives and processes DICOM­conformant images and supports up to four digital inputs. Sites with full-field digital
mammography (FFDM) systems can integrate ImageChecker D into their network
and view R2 Technology CAD results on their review workstations. Once configured,
little direct interaction with ImageChecker D is necessary. Any interaction is through
a user-friendly web browser interface.

ImageChecker D integrates easily into the clinical workflow. Following a mammo­graphy examination, the acquisition workstation sends digital images to the review
workstation as well as to the ImageChecker D system, which then analyzes the images
and sends the CAD results to the review workstation(s).

The radiologist reviews the original mammograms for a patient as he or she normally
would. At that point, the radiologist views the R2 Technology CAD results to
determine if any area on the original mammogram warrants further review.

After viewing the CAD results and performing any additional review, the radiologist
finishes the reading as he or she normally would.

2.4. Clinical Workflow

Images

F

Þ

Images

Examination

is performed

ImageChecker D
analyzes images

Workflow with ImageChecker D

CAD Results

Radiologist reviews

mammograms

 Note: With all review workstations (except those from Fischer Imaging), you can also

send ‘for processing’ images from the review workstation back to ImageChecker D for
analysis. (ImageChecker D can also process ‘for presentation’ images produced by GE
Senographe systems.) You might do this if the image was not analyzed when sent by the
acquisition workstation, for example, in the event that ImageChecker D was unavailable
for processing at that time.

ImageChecker D v8.1–8.3 User Manual – PN 14375 Rev 001 9