Low-cost 3D printing technology can be used for
clinical prototyping, demonstrated a study by researchers at the University of Würzburg in Würzburg, Germany. The findings are reported in the December issue of The Journal of Nuclear Medicine.
In nuclear medicine, the goal is to keep radiation exposure at a
minimum, while obtaining quality images. Optimal dosing for individual
patients can be difficult to determine. That's where 3D-printed organ
models of varying size and shape could be of great use.
‘Affordable 3D printing techniques hold the potential for manufacturing individualized anthropomorphic phantoms in many nuclear medicine clinical applications.’
Johannes Tran-Gia, the study's corresponding
author, explains, "This research shows a way of producing inexpensive
models of patient-specific organs/lesions for providing direct and
patient-specific calibration constants. This is particularly important
for imaging systems suffering from poor spatial resolution and
ill-defined quantification, such as SPECT/CT."
To demonstrate the potential of 3D printing techniques for
quantitative SPECT/CT imaging, kidneys - as organs-at-risk in many
radionuclide therapies - were selected for the study.
A set of four one-compartment kidney dosimetry phantoms and their
spherical counterparts with filling volumes between 8 mL (newborn) and
123 mL (adult) were designed based on the outer kidney dimensions
provided by Medical Internal Radiation Dose (MIRD) guidelines.
these designs, refillable, waterproof and chemically stable models were
manufactured with a fused deposition modeling 3D printer.
Nuclide-dependent SPECT/CT calibration factors for technetium-99m
(Tc-99m), lutetium-177 (Lu-177), and iodine-131 (I-131) were then
determined to assess the accuracy of quantitative imaging for internal
Tran-Gia notes, "Although in our study the kidneys were modeled as a
relatively simple one-compartment model, the study represents an
important step towards a reliable determination of absorbed doses and,
therefore, an individualized patient dosimetry of other critical organs
in addition to kidneys."
Ultimately, affordable 3D printing techniques hold the potential for
manufacturing individualized anthropomorphic phantoms in many nuclear
medicine clinical applications.