Analysis of individual positron emission tomography activation maps by high signal to noise ratio pixel clusters (HSC) detection

The authors present a new method for the analysis of individual brain PET (positron emission tomography) activation maps that looks for activated areas of a certain size rather than pixels with maximum values. High signal to noise ratio pixels clusters (HSC) are identified, and their sizes are statistically tested with respect to a Monte Carlo derived distribution of cluster sizes in pure noise images. The sensitivity and the specificity of this method have been assessed using realistic Monte Carlo simulations of brain activation maps. Compared to the gamma-2 statistic of the local maxima distribution, the proposed method showed enhanced sensitivity