抄録
The DSA system installed at the kumamoto University Hospital has recently been upgraded to permit 1024 × 1024 imaging. We compare d the physical properties of digital images produced by 512 × 512 matrix and 1024 × 1024 matrix using a star pattern and a contrastdetail (CD) phantom. It was confirmed by star pattern images that the digital images o b tained by 1024 × 1024 matrix showed improvement in spatial resolution as compared with 512 × 512 matrix. According to the observation by CD phantom images the detecta b ility of simulated vessels at highdose conditions was apparently better than that obtained at lowdose conditions for both matrix sizes. DSA images obtaind with equivalent dose settings were compared for two matrix sizes. DSA images produced by the 512 × 512 matrix provided better detectability than that of 1024 × 1024 matrix when observed under same exposure settings. Clinical stuby with intraarterial D S A demonstrated that the 1024 × 1024 matrix slightly improves in the vsibility of the vessels as compared with the 512 × 512 matrix. However, in clinical image with intervenous approach no significant improvement was confirmed between two matrix sizes.
