###
A generalized method for constant feature supression in digital
angiography

David A. Reimann and Joe P. Windham

World Congress on Medical and Biomedical Engineering, San Antonio,
Texas, 6-13 August.
*Physics in Medicine and Biology*, 33(Supplement I):8, 1988.

A method is presented which insures that the sum of the weighting
arguments of any temporal linear filter is zero, while preserving the
significant aspects of the filter. By insuring that this sum is zero,
constant features as well as noise which has an expected value of zero
is suppressed in the final image. A new sequence is formed by
subtracting the average image from each image in the original
sequence. This new sequence is used to define the signature vectors of
features that are to be enhanced and/or suppressed. These signatures
are used in the filter definition to create a new linear filter which
is then applied to the original sequence. A mathematical derivation of
the convolution of these two operations shows that the sum of the
weighting arguments of the new filter is zero. The method is applied
to the classical matched filter and the eigenimage filter. A
comparison is made between the technical characteristics of the
modified and the original filters. This method is illustrated on a
cardiac study and a simulated sequence.

Copyright ©
1988,
David A. Reimann. All rights reserved.