Current through Register Vol. 48, No. 12, March 22, 2024
The equipment requirements of this Section are intended to
ensure that mammography equipment is capable of producing quality mammograms
over the full range of clinical conditions.
a) Prohibited equipment. Radiographic
equipment designed for general purpose shall not be used for mammography.
Mammography shall only be performed with a special purpose radiation machine
specifically designed for and used solely for mammography procedures.
b) General. All radiographic equipment used
for mammography shall be certified under the "Performance Standards for
Diagnostic X-Ray Systems and their Major Components", published at
21 CFR
1020.30, effective as of April 1, 2012. Each
radiographic unit used for mammography shall be accredited by an approved
accrediting body or have an application for accreditation pending with an
approved accrediting body.
c)
Motion of tube-image receptor assembly.
1) The
assembly shall be capable of being fixed in any position where it is designed
to operate. Once fixed in any such position, it shall not undergo unintended
motion.
2) The mechanism ensuring
compliance with subsection (c)(1) shall not fail in the event of power
interruption.
d) Image
receptor sizes.
1) Systems using screen-film
image receptors shall provide, at a minimum, for operation with image receptors
of 18 x 24 centimeters (cm) and 24 x 30 cm.
2) Systems using screen-film image receptors
shall be equipped with moving grids matched to all image receptor sizes
provided.
3) Systems used for
magnification procedures shall be capable of operation with the grid removed
from between the source and image receptor.
e) Beam limitation and light fields.
1) All systems shall have beam-limiting
devices.
2) For any mammography
system with a light beam that passes through the x-ray beam-limiting device,
the light shall provide an average illumination of not less than 160 lux (15
foot candles) at 100 cm or the maximum source-image receptor distance (SID),
whichever is less.
f)
Magnification.
1) Systems used to perform
noninterventional problem solving procedures shall have radiographic
magnification capability available for use by the operator.
2) Systems used for magnification procedures
shall provide, at a minimum, at least one magnification value within the range
of 1.4 to 2.0.
g) Focal
spot selection.
1) When more than one focal
spot is provided, the system shall indicate, prior to exposure, which focal
spot is selected.
2) When more than
one target material is provided, the system shall indicate, prior to exposure,
the preselected target material.
3)
When the target material and/or focal spot is selected by a system algorithm
that is based on the exposure or on a test exposure, the system shall display,
after the exposure, the target material and/or focal spot actually used during
the exposure.
h)
Compression. All mammography systems shall incorporate a compression device.
1) Application of compression. Each system
shall provide:
A) An initial power-driven
compression activated by hands-free controls operable from both sides of the
patient; and
B) Fine adjustment
compression controls operable from both sides of the patient.
2) Compression paddle.
A) Systems shall be equipped with different
sized compression paddles that match the sizes of all full-field image
receptors provided for the system. Compression paddles for special purposes,
including those smaller than the full size of the image receptor (for "spot
compression") may be provided. The compression paddles for special purposes are
not subject to the requirements of subsections (h)(2)(D) and
(h)(2)(E).
B) Except as provided in
subsection (h)(2)(C), the compression paddle shall be flat and parallel to the
breast support table and shall not deflect from parallel by more than 1.0 cm at
any point on the surface of the compression paddle when compression is
applied.
C) Equipment intended by
the manufacturer's design to not be flat and parallel to the breast support
table during compression shall meet the manufacturer's design specifications
and maintenance requirements.
D)
The chest wall edge of the compression paddle shall be straight and parallel to
the edge of the image receptor.
E)
The chest wall edge may be bent upward to allow for patient comfort but shall
not appear on the image.
i) Technique factor selection and display.
1) Manual selection of milliampere seconds
(mAs) or at least one of its component parts (milliampere (mA) and/or time)
shall be available.
2) The
technique factors (peak tube potential in kilovolt (kV) and either tube current
in mA and exposure time in seconds or the product of tube current and exposure
time in mAs) to be used during an exposure shall be indicated before the
exposure begins, except when automatic exposure controls (AEC) are used, in
which case the technique factors that are set prior to the exposure shall be
indicated.
3) Following AEC mode
use, the system shall indicate the actual kilovoltage peak (kVp) and mAs used
during the exposure. The mAs may be displayed as mA and time.
j) Automatic exposure control.
1) Each screen-film system shall provide an
AEC mode that is operable in all combinations of equipment configuration
provided, e.g., grid, nongrid, magnification, nonmagnification and various
target-filter combinations.
2) The
positioning or selection of the detector shall permit flexibility in the
placement of the detector under the target tissue.
A) The size and available positions of the
detector shall be clearly indicated at the x-ray input surface of the breast
compression paddle.
B) The selected
position of the detector shall be clearly indicated.
3) The system shall provide means for the
operator to vary the selected optical density from the normal (zero)
setting.
k) X-ray film.
The facility shall use x-ray film for mammography that has been designated by
the film manufacturer as appropriate for mammography.
l) Intensifying screens. The facility shall
use intensifying screens for mammography that have been designated by the
screen manufacturer as appropriate for mammography and shall use film that is
matched to the screen's spectral output as specified by the
manufacturer.
m) Film processing
solutions. For processing mammography films, the facility shall use chemical
solutions that are capable of developing the films used by the facility in a
manner equivalent to the minimum requirements specified by the film
manufacturer.
n) Lighting. The
facility shall make special lights for film illumination, i.e., hot-lights,
capable of producing light levels greater than that provided by the view box,
available to the interpreting physicians.
o) Film masking devices. Facilities shall
ensure that film masking devices that can limit the illuminated area to a
region equal to or smaller than the exposed portion of the film are available
to all interpreting physicians interpreting for the facility.