Illinois Administrative Code › Title 32 - ENERGY › Part 370 - QUALITY STANDARDS AND CERTIFICATION REQUIREMENTS FOR FACILITIES PERFORMING MAMMOGRAPHY › Appendix B - Mammography Phantom Image Evaluation

Current through Register Vol. 48, No. 28, July 12, 2024
Mammography phantom image evaluation shall be performed using
				the procedure below. The evaluation shall be performed weekly as a part of the
				quality assurance program. The evaluation shall be performed with the
				mammography phantom specified in Section
				370.20 of this
				Part.
a) Equipment necessary for mammography phantom image
				evaluation includes a densitometer, the mammography phantom and mammographic
				cassette and film.
b) Load film in the mammographic cassette according
				to the manufacturer's instructions.
c) Place the properly loaded cassette in the
				cassette holder.
d) Place the mammography phantom on the breast
				support assembly (BSA) so that the edge of the phantom is aligned with the
				chest wall side of the BSA. Align the phantom so that the masses in the phantom
				are nearest the chest wall edge of the BSA and the fibers in the phantom are
				away from the chest wall edge of the BSA. If the mammography machine has the
				capability of automatic exposure control, place the phantom so that the phantom
				covers the phototimer sensor.
e) Position the compression device so that it is in
				contact with the phantom.
f) Select the technique factors used most frequently
				in the clinical setting for a 4.2 centimeter compressed breast and make an
				exposure of the phantom.
g) Process the film in the processor used for
				clinical mammography films.
h) Examine the processed image for areas of
				non-uniformity of optical density and for the presence of artifacts due to
				dirt, dust, grid lines or processing.
AGENCY NOTE: If any of the problems noted above are
				evident on the processed image, the mammography machine film processor and film
				cassette(s) should be evaluated and the problem corrected. The phantom image
				evaluation should be repeated after the problem is corrected.
i) Measure and record the optical density of the
				film near the center of the phantom image. The optical density of the film at
				the center of the image of the phantom shall be at least 1.20 when exposed
				under a typical clinical condition.
j) Examine the phantom image and count and record
				the number of masses visualized. Repeat this procedure for the speck groups and
				the fibrils and record the number of objects visualized. There are a total of
				16 imaging objects (5 masses, 5 speck groups and 6 fibrils) in the phantom.
				Evaluation criteria for objects visualized in the phantom image are in Section
				370.110(b)(3) of this Part. As a minimum, the objects that must be visualized
				in the phantom image are:
1) The masses that are 0.75 millimeter or larger (a
				total of 3 masses);
2) The speck groups that are 0.32 millimeter or
				larger (a total of 3 speck groups);
3) The fibrils that are 0.75 millimeter or larger (a
				total of 4 fibrils).
AGENCY NOTE: The phantom image should be compared with
				  previous films, including the original phantom image, to determine if subtle
				  changes are occurring from week to week.