A polygonization-based method is used to estimate the fractal dimension and
several new scalar lacunarity features from digitized transmission electro
n micrographs (TEM) of mouse liver cell nuclei. The fractal features have b
een estimated in different segments of 1D curves obtained by scanning the 2
D cell nuclei in a spiral-like fashion called "peel-off scanning". This is
a venue to separate estimates of fractal features in the center and periphe
ry of a cell nucleus. Our aim was to see if a small set of fractal features
could discriminate between samples from normal liver, hyperplastic nodules
and hepatocellular carcinomas. The Bhattacharyya distance was used to eval
uate the features. Bayesian classification with pooled covariance matrix an
d equal prior probabilities was used as the rule for classification.
Several single fractal features estimated from the periphery of the cell nu
clei discriminated samples from the hyperplastic nodules and hepatocellular
carcinomas from normal ones. The outer 25-30% of the cell nuclei contained
important texture information about the differences between the classes. T
he polygonization-based method was also used as an analysis tool to relate
the differences between the classes to differences in the chromatin structu
re.