Fig 1.

Illustration of Dice and Hausdorff metrics. (a) The Dice metric compares two enclosed areas. The area of overlap (multiplied by two) is divided by the total areas of the combined annotations. A higher figure indicates stronger agreement (0=no agreement, 1=complete agreement). (b) The Hausdorff metric compares two line annotations. The distance between each point in line A is compared to all points in line B. The minimum distance of this group is calculated. This is repeated for each point in line A. The maximum of these minimum values is then taken. A lower figure indicates stronger agreement (0=complete agreement, 1=lines separated by maximum length/width of image).