Low tube current scanning in combination with HYPR (HighlY constrained backPRojection) noise reduction is a proposed method for low-dose time-resolved CT myocardial perfusion imaging. We report animal studies and simulations investigating the coronary angiographic information available in these scans. Four pigs were scanned at 100 rnA and 500 rnA. A HYPR coronary angiographic image was formed from each 100 rnA scan by producing a time-averaged composite image from cardiac cycles centered on the time of peak left ventricular intensity and then multiplying the composite by a weighting image to restore image intensities. Image noise, coronary artery cross sectional area, and coronary artery intensity were measured as a function of the number of beats in the composite, weighting image filtration, and coronary artery size. HYPR images maintained coronary artery area and intensity to within 6-8% of of filtered back projection (FBP) image values, on average, for vessels with cross sectional area greater than 2 mm². Vessel visibility in 100-mA HYPR images was improved relative to 100-mA FBP, in cross sectional and multiplanar reformatted images.

Date Published: 19 March 2013
PDF: 6 pages
Proc. SPIE 8668, Medical Imaging 2013: Physics of Medical Imaging, 866840 (19 March 2013); doi: 10.1117/12.2007719

Published in SPIE Proceedings Vol. 8668:
Medical Imaging 2013: Physics of Medical Imaging
Robert M. Nishikawa; Bruce R. Whiting; Christoph Hoeschen, Editor(s)