AUTHOR=Wolf Marcos , Kommer Stefan , Fembek Sebastian , Dröszler Uwe , Körner Tito , Berg Andreas , Schmid Albrecht Ingo , Moser Ewald , Meyerspeer Martin 

TITLE=Reproducible phantom for quality assurance in abdominal MRI focussing kidney imaging

JOURNAL=Frontiers in Physics

VOLUME=10

YEAR=2022

URL=https://www.frontiersin.org/journals/physics/articles/10.3389/fphy.2022.993241

DOI=10.3389/fphy.2022.993241

ISSN=2296-424X

ABSTRACT=<p>Quality assurance (QA) in magnetic resonance imaging (MRI) requires test objects. ‘Phantoms’ provided by MR manufacturers are homogeneously filled spheres or cylinders, and commercially available products are often too small for abdominal imaging, particularly for enlarged polycystic kidneys. Here we present the design, manufacturing and testing of a dedicated, yet versatile, abdominal MRI phantom, that can be reproduced with relatively low costs. The phantom mimics a human abdomen in size and shape and comprises seven test fluids, representing various tissue types at 3 T. The conductivity and permittivity of the test fluids match the average abdomen and kidney with a relative permittivity (ε) 65 and 72 as well as conductivity 0.6 and 0.7 S/m, respectively. The T<sub>1</sub> and T<sub>2</sub> relaxation times cover healthy average abdomen and kidney tissue values (T<sub>1(abd)</sub>: 856 ms and T<sub>1(kid)</sub>: 1,106 ms; T<sub>2(abd)</sub>: 52 ms and T<sub>2(kid)</sub>: 67 ms), intermediate (T<sub>1</sub>: 1,183 ms and 1,271 ms; T<sub>2</sub>: 128 and 189 ms), and disease values for (polycystic) kidney (T<sub>1</sub>: 1,428 ms, 1,561 ms and 1763 ms; T<sub>2</sub>: 319 ms, 424 and 647 ms). T<sub>1</sub> and T<sub>2</sub> relaxation times were stable over 73 weeks. Our reasonably priced, durable and reproducible abdominal phantom enables single and multi-center QA for future collaborative studies aiming for various challenges around abdominal and, particularly, kidney imaging.</p>