Journal of Ultrasound in Medicine, Vol 19, Issue 6 391-398, Copyright © 2000 by American Institute of Ultrasound in Medicine
Effect of spectacular reflection on out-of-plane ultrasonographic images reconstructed from three-dimensional data sets
R. O. Bude and T. Tuthill
Department of Radiology, University of Michigan Medical Center, Ann Arbor 48109-0030, USA.
The effect of specular reflection on ultrasonographic images reconstructed
out of plane to the plane of acquisition of a three-dimensional volumetric
data set was studied using two in vitro phantoms that incorporated
structures exhibiting specular reflection. The phantoms were scanned
transversely (axially) to form three-dimensional data sets, with coronal
cross-sectional images reconstructed perpendicular to the plane of
acquisition of the data sets. Directly scanned, nonreconstructed coronal
images of the phantoms also were obtained in the same planes and from the
same areas as the reconstructed coronal images. The direct and
reconstructed coronal images were compared. Owing to the inherent
directionality of specular reflectors, the reconstructed coronal images
differed from the directly scanned images in two ways, containing some
hyperechoic regions that were not present at direct coronal scanning and
failing to contain other hyperechoic areas that were present at direct
coronal imaging. We conclude that sonographic images reformatted from
volumetric data sets may have a different appearance than images scanned
directly in the same plane, independent of other factors such as
resolution. This should be taken into account when such reformatted images
are interpreted.
