VHBASE

vhbase − projects the heart region down below diaphragm.

vhbase if=<hrtmap> zres=<zres> of=<newmap>

vhbase takes in the segmented heart region and projects it down below the diaphragm. First it starts from 20mm above the base of heart and check the heart region slice by slice for rapid length change (more than 10% compared to previous slice). If such change is detected, heart is terminated before that slice. This is considered as the robustly constrained heart region. Then starting from the robust region, heart is projected down slice by slice for 40mm. Then for each slice, the algorithm checks for the boundary pixels of the projected region. If less than 20% of the boundary pixels are adjacent to fat or lung pixels, the projection is terminated before that slice. The descending aorta is also terminated when the projection terminates.

Input file if is the constrained heart region (output from vhcont). Output file of is a map with the original heart and projected heart region in different labels. It also has the comstrained aorta (both ascending and descending) based on heart region.

vhcont(1)

Y. Xie