How to measure the Aortic valve's annulus diameter(s), and the vertical distance between the annulus and the sinotubular junction by 3D Slicer and/or SlicaeHeart using cardiac CT scans?

Please advise on how to measure the Aortic valve’s annulus diameter(s), and the vertical distance between the annulus and the sinotubular junction by 3D Slicer and/or SlicaeHeart using cardiac CT scans?