• Home
  • Search Results
  • Accuracy of iodine removal using dual-energy CT with or without a tin filter: an experimental phantom study.

Accuracy of iodine removal using dual-energy CT with or without a tin filter: an experimental phantom study.

Acta radiologica (Stockholm, Sweden : 1987) (2013-04-25)
Tatsuya Kawai, Mitsuru Takeuchi, Masaki Hara, Kazuya Ohashi, Hirochika Suzuki, Kiyotaka Yamada, Yuya Sugimura, Yuta Shibamoto
ABSTRACT

The effects of a tin filter on virtual non-enhanced (VNE) images created by dual-energy CT have not been well evaluated. To compare the accuracy of VNE images between those with and without a tin filter. Two different types of columnar phantoms made of agarose gel were evaluated. Phantom A contained various concentrations of iodine (4.5-1590 HU at 120 kVp). Phantom B consisted of a central component (0, 10, 25, and 40 mgI/cm(3)) and a surrounding component (0, 50, 100, and 200 mgI/cm(3)) with variable iodine concentration. They were scanned by dual-source CT in conventional single-energy mode and dual-energy mode with and without a tin filter. CT values on each gel at the corresponding points were measured and the accuracy of iodine removal was evaluated. On VNE images, the CT number of the gel of Phantom A fell within the range between -15 and +15 HU under 626 and 881 HU at single-energy 120 kVp with and without a tin filter, respectively. With attenuation over these thresholds, iodine concentration of gels was underestimated with the tin filter but overestimated without it. For Phantom B, the mean CT numbers on VNE images in the central gel component surrounded by the gel with iodine concentrations of 0, 50, 100, and 200 mgI/cm(3) were in the range of -19-+6 HU and 21-100 HU with and without the tin filter, respectively. Both with and without a tin filter, iodine removal was accurate under a threshold of iodine concentration. Although a surrounding structure with higher attenuation decreased the accuracy, a tin filter improved the margin of error.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Agarose, BioReagent, for molecular biology, low EEO
Sigma-Aldrich
Agarose, Type I, low EEO
Sigma-Aldrich
Agarose, for molecular biology
Sigma-Aldrich
Agarose, Low EEO
Sigma-Aldrich
Agarose, Ultra-low Gelling Temperature, molecular biology grade
Sigma-Aldrich
Sepharose® 4B, 45-165 μm bead diameter
Sigma-Aldrich
Tin, ≥99%, powder
Sigma-Aldrich
Agarose, Medium EEO, for molecular biology
Sigma-Aldrich
Tin, powder, <150 μm, 99.5% trace metals basis
Sigma-Aldrich
Agarose, Ultra-low Gelling Temperature
Sigma-Aldrich
Agarose, Type I-A, low EEO
Sigma-Aldrich
Tin, nanopowder, <150 nm particle size (SEM), ≥99% trace metals basis
Sigma-Aldrich
Tin, powder, -100 mesh, 99.99% trace metals basis
Sigma-Aldrich
Tin, granular, 0.425-2.0 mm particle size, ≥99.5%, ACS reagent
Sigma-Aldrich
Agarose, Type II-A, Medium EEO
Sigma-Aldrich
Agarose, Wide range, for molecular biology
Sigma-Aldrich
Sepharose® 6B, 6% Beaded Agarose, 45-165 μm (wet), fractionation range 10,000-1,000,000 Da (dextrans)
Sigma-Aldrich
Agarose, High Gelling Temperature
Sigma-Aldrich
Agarose, Low EEO, for Immunoelectrophoresis
Sigma-Aldrich
Agarose, High EEO, for molecular biology
Sigma-Aldrich
Agarose, For pulsed field electrophoresis running gel
Sigma-Aldrich
Tin, powder, <45 μm particle size, 99.8% trace metals basis
Sigma-Aldrich
Tin, foil, thickness 0.5 mm, 99.998% trace metals basis
Sigma-Aldrich
Tin, shot, 99.999% trace metals basis
Sigma-Aldrich
Agarose, High EEO
Sigma-Aldrich
Tin, powder, 10 μm, 99% trace metals basis
Sigma-Aldrich
Tin, wire, diam. 0.5 mm, 99.999% trace metals basis
Sigma-Aldrich
Agarose, BioReagent, for molecular biology, Wide range/Standard 3:1
Sigma-Aldrich
Tin, 99.8%, shot, 3 mm
Sigma-Aldrich
Tin, foil, thickness 0.127 mm, 99.9%