Role of computed tomography voxel size in detection and discrimination of calcium and iron deposits in atherosclerotic human coronary artery specimens.
OBJECTIVE
This study evaluated the influence of voxel size on its ability to discriminate calcium from iron deposits in ex vivo coronary arteries.


METHODS
Postmortem human coronary arteries underwent multislice computed tomographic scan at (600-microm) voxel size to provide an index of computed tomography (CT) image noise and synchrotron-based micro-CT at (4-microm) voxel size to provide data for generating a range of voxel sizes 4 to (600-microm) after grayscale noise was added to the projection images before reconstruction so as to mimic the effect of retaining the same radiation exposure involved in the multislice computed tomographic scan.


RESULTS
At voxel sizes of (20-microm) or smaller, iron deposits could be identified based on CT grayscale value. Voxels of (100-microm) or larger cannot resolve nor distinguish iron deposits from calcifications by virtue of CT grayscale value.


CONCLUSIONS
Clinical CT scanners cannot be expected to discriminate iron deposits from calcifications by their CT value alone in the arterial wall.
Langheinrich
Alexander C
AC
Department of Radiology, Justus Liebig University Giessen, Giessen, Germany.
Kampschulte
Marian
M
Crössmann
Christine
C
Moritz
Regina
R
Rau
Wigbert S
WS
Bohle
Rainer M
RM
Ritman
Erik L
EL
D001344:Autopsy; D002114:Calcinosis / Q000000981:diagnostic imaging*; D002118:Calcium / Q000032:analysis*; D017023:Coronary Angiography / Q000379:methods; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging*; D006486:Hemosiderosis / Q000000981:diagnostic imaging*; D006801:Humans; D007501:Iron / Q000032:analysis*; D014057:Tomography, X-Ray Computed / Q000379:methods*; D055114:X-Ray Microtomography / Q000379:methods
D007501:Iron; D002118:Calcium