Optimized radiographic spectra for small animal digital subtraction angiography.

Published

Journal Article

The increasing use of small animals in basic research has spurred interest in new imaging methodologies. Digital subtraction angiography (DSA) offers a particularly appealing approach to functional imaging in the small animal. This study examines the optimal x-ray, molybdenum (Mo) or tungsten (W) target sources, and technique to produce the highest quality small animal functional subtraction angiograms in terms of contrast and signal-difference-to-noise ratio squared (SdNR2). Two limiting conditions were considered-normalization with respect to dose and normalization against tube loading. Image contrast and SdNR2 were simulated using an established x-ray model. DSA images of live rats were taken at two representative tube potentials for the W and Mo sources. Results show that for small animal DSA, the Mo source provides better contrast. However, with digital detectors, SdNR2 is the more relevant figure of merit. The W source operated at kVps >60 achieved a higher SdNR2. The highest SdNR2 was obtained at voltages above 90 kVp. However, operation at the higher potential results in significantly greater dose and tube load and reduced contrast quantization. A reasonable tradeoff can be achieved at tube potentials at the beginning of the performance plateau, around 70 kVp, where the relative gain in SdNR2 is the greatest.

Full Text

Duke Authors

Cited Authors

  • Lin, MD; Samei, E; Badea, CT; Yoshizumi, TT; Johnson, GA

Published Date

  • November 2006

Published In

Volume / Issue

  • 33 / 11

Start / End Page

  • 4249 - 4257

PubMed ID

  • 17153403

Pubmed Central ID

  • 17153403

International Standard Serial Number (ISSN)

  • 0094-2405

Digital Object Identifier (DOI)

  • 10.1118/1.2356646

Language

  • eng

Conference Location

  • United States