Fig. 2

Schematic illustration of the creation of the side of the NC using part of a circle. To calculate the center point of the circle used for creation of the side of the NC a combination of circles was used. The center of circle 1 was located at the edge of the necrotic core. One point in circle 1 intersects the cap, and this point is used as center point for circle 2. Then the two circles intersect at two locations, and the intersection most distant from the lumen was the center point of the final blue circle (3) for the side of the necrotic core (blue dot). Together with the empirically determined radius and angle the side can be reconstructed, see the black dotted line