X-ray phase contrast for CO2 microangiography
2012 (English)In: Physics in Medicine and Biology, ISSN 0031-9155, E-ISSN 1361-6560, Vol. 57, no 9, 2603-2617 p.Article in journal (Refereed) Published
We demonstrate a laboratory method for imaging small blood vessels using x-ray propagation-based phase-contrast imaging and carbon dioxide (CO2) gas as a contrast agent. The limited radiation dose in combination with CO2 being clinically acceptable makes the method promising for small-diameter vascular visualization. We investigate the possibilities and limitations of the method for small-animal angiography and compare it with conventional absorption-based x-ray angiography. Photon noise in absorption-contrast imaging prevents visualization of blood vessels narrower than 50 mu m at the highest radiation doses compatible with living animals, whereas our simulations and experiments indicate the possibility of visualizing 20 mu m vessels at radiation doses as low as 100 mGy. Experimental computed tomography of excised rat kidney shows blood vessels of diameters down to 60 mu m with improved image quality compared to absorption-based methods. With our present prototype x-ray source, the acquisition time for a tomographic dataset is approximately 1 h, which is long compared to the 1-20 min common for absorption-contrast micro-CT systems. Further development of the liquid-metal-jet microfocus x-ray sources used here and high-resolution x-ray detectors shows promise to reduce exposure times and make this high-resolution method practical for imaging of living animals.
Place, publisher, year, edition, pages
2012. Vol. 57, no 9, 2603-2617 p.
Angiography, Blood vessels, Carbon dioxide, Dosimetry, Image quality, Imaging techniques, Visualization, X ray apparatus, X rays
Radiology, Nuclear Medicine and Medical Imaging
IdentifiersURN: urn:nbn:se:kth:diva-95082DOI: 10.1088/0031-9155/57/9/2603ISI: 000303046200015PubMedID: 22505599ScopusID: 2-s2.0-84860168376OAI: oai:DiVA.org:kth-95082DiVA: diva2:527679
FunderSwedish Research CouncilScience for Life Laboratory - a national resource center for high-throughput molecular bioscience
QC 201205222012-05-222012-05-142015-03-31Bibliographically approved