Fig. 6From: Comparison of Otsu and an adapted Chan–Vese method to determine thyroid active volume using Monte Carlo generated SPECT imagesDeviation of size estimation for 35 ml phantom. The calculated volumes for the 35 ml phantom, of Chan–Vese and Otsu method, relative to true size per relative background activity concentration (rows from bottom to top show 5, 10, 15 and 20 %) and relative hotspot activity concentration (columns from left to right show 100, 150, 200 and 250 %). The figures below each panel show the deviation (in percentages) from true sizeBack to article page