|The Alderson Radiation Therapy phantom (ART)
and its earlier version, the Alderson RANDO phantom, have been
in use for over 30 years. The ART has been refined and
improved in both design and materials. These phantoms are
indispensable quality-assurance tools; about 10,000 are in use
all over the world. They provide integrated tests of the
entire chain of treatment planning and delivery.
ART phantoms are molded of tissue-equivalent material; they
are designed within highly sophisticated technological
constraints and follow ICRU-44 standards. They are also
designed for accuracy and ease of use. a large female.
The male ART represents a 175 cm (5 ft. 9 in.) tall, 73.5 kg
(162 lb.) male, and the female ART represents a 155 cm (5 ft.
1 in.) tall, 50 kg (110 lb.) female.
The ART phantom is transected-horizontally into 2.5 cm thick
slices. Each slice has holes which are plugged with
bone-equivalent, soft-tissue-equivalent or lung tissue
equivalent pins which can be replaced by TLD holder pins. The
holder pins are ordered separately.
Soft-tissue-equivalent coatings produce slices with glass
smooth interfaces. These coatings are cut away over the air
spaces of the oronasal pharynges, trachea and stem bronchi.
Dosimetry holes are drilled in grids 3 cm x 3 cm or 1.5 cm x
in 5 and 7 mm diameters. These afford detailed measurements of
There is poor correlation between clothing brassiere sizes and
breast volumes. Breasts are specified according to this table:
Approximate Clothing Size
Breasts are available in various sizes. They can be sliced in
frontal planes (drilled or undrilled for film dosimetry). Slices
can receive any of the pins listed below. Breasts of male and
female ART phantoms are contoured to blend realistically
with the thoraxes. They are attached to the thorax with
nylon screws. The male chest with breasts attached serves as
a large female.
Soft Tissues: There are unlimited, small variations in
density and absorption throughout the human body. Phantom soft
tissue is closely controlled to have the average density of
Skeletons: RSD skeletons are highly-detailed polymer
moldings which reproduce the shape, mass density and
attenuation coefficients of cortical bone and spongiosa. They
allow continuous production of phantoms, instead of the
sporadic production required by the limited availability,
variable size and uncertain chemical composition of human
skeletons. These problems, plus loss of marrows in dried
natural skeletons, make RSD skeletons superior to "real bone".
Molds for the RSD cortical bone and spongiosa were made from
human skeletons consistent with the sizes of the softtissue
RSD skeletons conform closely to the standards established by
the International Commission on Radiation Units and
Measurements (ICRU Report No. 44); mass density is reduced
slightly to take into account a small decrease in calcium
content for older patients.
Lungs: Lungs are molded from syntactic foam, with a
specific gravity of 0.30 g/cc.
Phantoms are shipped with all dosimetry holes filled with
blank pins. Pins for TLD chips have recesses at one end 3.2 x
3.2 x 0.9 mm. Pins for TLD rods have 1 mm-diameter holes
cross-drilled at the centers of the pins. All pins are 2.50 cm
long unless otherwise specified.
Holders ÃÂÃÂ 5 mm or 7 m
1 mm diameter x 3 mm long ÃÂÃÂ 5 mm or 7 mm
1 mm diameter x 6 mm long ÃÂÃÂ 7 mm only
Pins ÃÂÃÂ 5 mm diameter
ART-20-S, L, B
Pins ÃÂÃÂ 7 mm diameter
ART-21-S, L, B
|S = Soft
L = Lung Tissue Equivalent
B = Bone Tissue Equivalent
Note: ART-10 and ART-12 are
interchangeable in ART phantoms.
ART phantom slices are held between aluminum plates by nylon
tie rods. Knobs at the end of the rods clamp the slices
tightly in proper alignment.
Both internal and external assembly devices are included. The
external assembly facilitates film dosimetry, while the
internal assembly is used generally with TLDs or ionchamber
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