PROBLEM TO BE SOLVED: To provide a tumor contour extraction program capable of reducing variations in results of extraction done by operators and reducing work to be done by operators in image analysis of nuclear medicine image data.SOLUTION: A computer program for extracting tumor contours from nuclear medicine image data performs steps including highlighting a region with a tumor setting a reference point in the highlighted region scanning pixels three-dimensionally and radially from the reference point producing a pixel value profile in each scanning direction producing a gradient strength profile for the pixel value profile or a smoothing-processed version of the pixel value profile extracting a range in which the pixel value monotonically increases or monotonically decreases from the pixel value profile or the smoothing-processed pixel value profile and designating the extracted range as a contour determination range and determining tumor contour points in the pixel value profile based on a peak with the maximum kurtosis within the contour determination range on the corresponding gradient strength profile or a smoothing-processed version of the gradient strength profile.SELECTED DRAWING: Figure 7ACOPYRIGHT: (C)2016,JPO&INPIT
