TITLE:
Medical Image Registration Using the Fourier Transform
AUTHORS:
Jason Luce, James Gray, Mark A. Hoggarth, Jeffery Lin, Elizabeth Loo, Maria I. Campana, John C. Roeske
KEYWORDS:
Image Registration; Fourier Transform; Pattern Matching
JOURNAL NAME:
International Journal of Medical Physics, Clinical Engineering and Radiation Oncology,
Vol.3 No.1,
February
20,
2014
ABSTRACT:
A Fourier
Transform (FT) based pattern-matching algorithm was adapted for use in medical
image registration. This algorithm obtained the FT of two images, determined
the normalized cross-power spectrum of the transformed images, and then applied
an inverse FT. The result was a delta function with a maximum value at the
location corresponding to the distance between the two images; a similar method
was used to recover rotations. This algorithm was first tested using a simple
two-dimensional image, with induced shifts of ±20 pixels and ±10 degrees. All
translations were recovered with no error and all rotations were recovered
within 0.18 degrees. Subsequently, this algorithm was tested on eight clinical
kV images drawn from four different body sites. Twenty-five random shifts and
rotations were applied to each image. The average mean error of the
registration solution was -0.002 ± 0.077 mm in the x direction, 0.002 ± 0.075
mm in the y direction, and -0.012 ± 0.099 degrees. These initial results suggest that a FT algorithm has a high degree of
accuracy when registering clinical kV images.