Specification and Testing of
Radiographic Systems For Breast Biopsy
William Geiser, MS DABR
Senior Medical Physicist
UT MD Anderson Cancer Center
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Introduction
• Types of specimen radiography systems
• The procedure – getting the images
• Laws and regulations
• TG
TG--209 Proposed specifications and testing
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Mastectomy Specimen
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Mastectomy Specimen Zoomed
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2
Contact Radiograph
24x30 cm cassette
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Segmental Mastectomy Gross specimen
Image
Patient Info
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Patient Info
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3
Segmental Sliced
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Segmental Sliced Zoomed
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Patient Info
Patient Info
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Why the sliced specimen
• Radiological and pathological size estimations of pure
ductal carcinoma in situ of the breast, specimen
handling and the influence on the success of breast
conservation surgery: a review of 2564 cases from the
Sloane Project.
• Thomas JJ,, Evans A
A,, Macartney J,
J, Pinder SE
SE,, Hanby A
A,,
O,, Roberts T
T,, Clements K
K,, Lawrence G
G,,
Ellis I,
I, Kearins O
Group.
Bishop H;
H; Sloane Project Steering Group.
• The agreement between pathological and radiological size
of DCIS was poor in mastectomies but was improved by
specimen slice radiography, suggesting specimenspecimen-handling
techniques as a cause.
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Stereotactic Breast Biopsy
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3:1
Magnification
18x24 cm CR
Cassette
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Cabinet xx-ray systems are used to perform
radiography of breast specimens in both the
stereotactic breast biopsy suite and in the operating
room. What type of specimens are imaged in the
operating room?
0% 1.
0%
0%
0%
0%
Stereotactic breast biopsy specimens
2. Mastectomy specimens
3. Segmental mastectomy specimens
4. Ultrasound guided biopsy specimens
5. Both segmental and full mastectomy
specimens
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Answer
5 – Both segmental and full mastectomy
specimens
Ref:
http://EzineArticles.com/?expert=Dr._Nitha
_Thejal
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Regulations
• Current Regulations
– FDA
– State
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FDA Statements
• Some cabinet xx-ray systems are used for medical
applications, such as analyzing tissue samples for
tumor metastases. These systems are medical
devices and subject to additional FDA regulations.
• Use of cabinet xx--ray products is regulated either by
the U.S. Occupational Safety & Health
Administration11 or by State Government.
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Who regulates the QC testing required to be
performed on specimen xx-ray systems?
0% 1.
Food and Drug Administration
0% 2.
2
N l Regulatory
Nuclear
R l t
Commission
C
i i
0% 3.
Individual State Radiation Control Programs
0% 4.
Mammography Quality Standards Act
0% 5.
OSHA
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Answer
• 3 – Individual State Radiation Control
Programs
• Ref: 21 CFR 1020.40 :
http://www.fda.gov/Radiation-http://www.fda.gov/Radiation
EmittingProducts/RadiationEmittingProduct
sandProcedures/SecuritySystems/ucm22719
6.htm
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FDA – Code of Federal Regulations
• Cabinet XX-ray Systems - FDA
– 21CFR1020.40
•
•
•
•
•
•
•
Radiation Emission Limit
Fl
Floors
Ports and Apertures
Interlocks
Ground Faults
Controls and Indicators
Operating Procedures and Technical Manuals
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Cabinet X
X--ray Systems
• Texas Regulations
– 25 TAC 289.228
• This section establishes requirements for the use of
industrial radiation machines not otherwise covered by this
chapter. For purposes of this section, industrial radiation
machines include, but are not limited to, portable/handheld
fluorescence xx--ray (open beam), fluoroscopy hand held
intensified, fluoroscopy xx--ray, industrial accelerator,
spectrography xx-ray, flash xx--ray, flash xx--ray for bomb
detection, educational facility (x(x-ray for nonnon-human or not
live animal use), diffraction xx--ray, uncertified cabinet xx--ray,
and minimal threat radiation machines
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• No registrant shall permit any individual to operate a
cabinet xx--ray system until the individual has received a
copy of and instruction in the operating procedures for the
unit.
• Tests for proper operation of interlocks shall be conducted
and recorded at intervals not to exceed 12 months
• The registrant shall perform an evaluation to determinate
compliance with §289.231(o)(1)
289.231(o)(1)--(3) of this title and Title
21, CFR, §1020.40 at intervals not to exceed one year. The
registrant shall ensure that radiation emitted 5 centimeters
from the external surface of the cabinet xx-ray system does
not exceed 0.5 millirem (5.0 mSv) in any one hour.
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• (c)
(c)Requirements
Requirements –
– (1)Emission
(1)Emission limit. (i) Radiation emitted from the
cabinet xx-ray system shall not exceed an
exposure of 0.5
0 5 milliroentgen in one hour at any
point five centimeters outside the external
surface
– http://www.fda.gov/Radiationhttp://www.fda.gov/RadiationEmittingProducts/RadiationEmittingProductsandProced
ures/SecuritySystems/ucm227196.htm
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• (ii) Compliance with the exposure limit in paragraph
(c)(1)(i) of this section shall be determined by
measurements averaged over a crosscross-sectional area of ten
square centimeters with no linear dimension greater than 5
centimeters, with the cabinet xx--ray system operated at those
combinations of xx-ray tube potential,
potential current,
current beam
orientation, and conditions of scatter radiation which
produce the maximum xx-ray exposure at the external
surface, and with the door(s) and access panel(s) fully
closed as well as fixed at any other position(s) which will
allow the generation of x radiation
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What is the maximum allowable exposure limit for
cabinet xx-ray systems
0% 1.
0.05 mR in one hour
0% 2.
2
0 1 mR
0.1
R iin one hour
h
0% 3.
0.25 mR in one hour
0% 4.
0. 5 mR in one hour
0% 5.
1.0 mR in one hour
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Answer
• 4. 0.5 mR in one hour
• Ref: 21CFR1020.40(c)(1)(i)
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The Measurement
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Low Energy Window Open
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Exposure Measurement
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Specification of Specimen X
X--ray systems
• Must be FDA Approved!!
– Bioptics
– Faxitron
– Kubtec
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Stereotactic Breast Biopsy Specimen
X-ray System
• X-ray Tube
• Magnification
• Field Size
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Field Size
• Large enough to image a 5 cm diameter
specimen dish at the proposed magnification
factor
• All systems at least 12 x 12 cm
• We use a 18 x 24 cm Mammography CR
cassette
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12
Specimen Dish
4.8 cm
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X-ray Tube Specifications Cabinet
Systems
Specification
Faxitron MX 20
Bioptics Biovision
Kubtec Xpert 40
kVp
10 kVp ‐ 35 kVp
5 kVp ‐ 45 kVp
10 kVp ‐ 50 kVp
mA
300 µA
1.5 mA
1.0 mA
Focal Spot
< 20 µm
50 µm
?
Window Filtration
0.01 " Beryllium
0.125 mm Beryllium
0.005 mm Beryllium
Resolution
10 lp/mm
Active Imaging Area
12 cm x 12 cm
10 lp/mm
10 cm x 15 cm, 12 cm x 18 cm
?
5 cm x 5 cm up to
20 cm x 20 cm
Magnification
?
1:1, 2:1, 4:1
up to 5x
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Specifications Core Biopsy Systems
Specification
Faxitron DX ‐50
Bioptics Core Vision
Kubtec Xpert 20
kVp
10 kVp ‐ 35 kVp
5 kVp ‐ 30 kVp
10 kVp ‐ 25 kVp
mA
0.1 mA
0.35 mA
1.0 mA
Focal Spot
50 µm
?
?
Window Filtration
0.2 mm beryllium
0.005" beryllium
Resolution
0.03" beryllium
10 lp/mm or 20 lp/mm
35 micron
Active Imaging Area
5 cm x 5 cm
3 cm x 7 cm
?
5 cm x 5 cm
5 cm x 10 cm
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What is smallest detector size provided by any of the
vendors for stereotactic core biopsy imaging?
0% 1.
3 cm x 7 cm (21 cm2)
0% 2.
2
5 cm x 5 cm (25 cm2)
0% 3.
10 cm x10 cm (100 cm2)
0% 4.
15 cm x15 cm (225 cm2)
0% 5.
20 cm x 20 cm (400 cm2)
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Answer
• 1. 3 cm x 7 cm (21 cm2)
• Ref
Ref:: Ref: Bioptics Core vision technical specifications:
http://www
http://www.bioptics
http://www.biopticsbiopticsbiopticsinc.com/site/downloads/COREVISION_Brochure.pdf#zoom=60
• Faxitron DXDX-50 Core Specimen Radiography System technical
specifications: http://www.faxitron.com/pdf/Faxitron_DX
http://www.faxitron.com/pdf/Faxitron_DX-50_Core_Datasheet.pdf
• Kubtec Xpert20 Specimen Radiography System technical
specifications: http://www.kubtec.com/xpert20.htm
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QC Testing – AAPM TG 209
• Proposed testing
–
–
–
–
–
–
–
Safety Check
kVp
Exposure Rate
Resolution - Detector
Image quality phantom
Film Processor
CR Reader testing
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End
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