Contrast Agent Dual Energy Imaging: Computer Simulations In Search For Printing Materials

Abstract

Contrast-enhanced dual-energy is considered as one of the best techniques in mammography especially for women with dense breast and has shown certain benefits compared to digital mammography. Current study performs contrast-enhanced dual-energy imaging computer simulation of a 5 cm thick object with iodine-based contrast filling. The simulated material used for the object was resin, a material used in three-dimensional printing, serving as a background, and iohexol, used as a contrast media. Imaging was simulated using four different energy settings 50 kVp, 80 kVp, 100 kVp and 120 kVp. Simulation images were processed and then subtraction weighed coefficients that provide best contrast were determined and compared to the theoretical. Feasibility of use of selected materials was confirmed for further creation of a printed phantom.

Contrast Enhanced Radiography with a Printed Model

“…Best contrasts for pairs 70 -80 kVp, 70 -100 kVp, 70 -120 kVp, 80 -100 kVp, 80 -120 kVp and 100 -120 kVp were achieved with coefficients close to 1 that means almost no weighted subtraction. The comparison of experimental and simulated weighted coefficients showed a difference up to 13% [14]. This is due to several factors such as variations of the chemical properties of the resin used for printing, the noise in the experimental images, as well as some slight differences in the simulated geometry.…”

“…Table I summarises the results for the weighted coefficients corresponding to the maximum contrast of iodine objects. In the same table, the analytical coefficients from the simulation study are listed [14]. As seen from Table I, the best contrast ratesbetween 123 and 332 were achieved with low energies at 50 kVp or 70 kVp and high energies -100 kVp or 120 kVp.…”

“…In order to perform the study a physical phantom was created by means of 3D printing. The physical phantom is based on a computational model used in a simulation study [14]. Furthermore, contrast medium was used together with the phantom and the resulting x-ray images acquired from various energies were evaluated.…”

“…There are 10 cylindrical holes made on the top of the parallelepiped, each of them is 8 mm in diameter and ranging from 0.1 mm to 1.0 mm in depth. The computational phantom size and material used for the manufacture mimics a compressed dense breast as reported previously in [14]. The model was printed with a stereolithography (SLA) 3D printer Form 3 (FormLabs, Sommerville, MA, USA) with the commercially available printing material Formlabs Clear V4 resin.…”