SHAPE_Sphericity is how spherical a Volume of Interest is. Sphericity is equal to 1 for a perfect sphere.
\begin{equation}
SHAPE\_Sphericity=\frac{\pi^{1/3}\cdot(6V)^{2/3}}{A}
\end{equation}
where \(V\) and \(A\) correspond to the volume and the surface of the Volume Of Interest based on the Delaunay triangulation.
SHAPE_Compacity reflects how compact the Volume of Interest is.
\begin{equation}
SHAPE\_Compacity=\frac{A^{3/2}}{V}
\end{equation}
where \(V\) and \(A\) correspond to the volume and the surface of the Volume Of Interest based on the Delaunay triangulation.
see:
- https://patents.google.com/patent/US6169817
- https://en.wikipedia.org/wiki/Compactness_measure_of_a_shape
SHAPE_Volume (mL and voxels) is the Volume of Interest in mL and in voxels.
\begin{equation}
SHAPE\_Volume=\sum_{i} V_i
\end{equation}
where \(V_i\) correspond to the volume of voxel \(i\) of the Volume Of Interest.