acually  i do not understand this dataset at all , but i was thinking of using reference.CAT  file
in dataset_xx folder as grountruth for DICOM files in each dataset_xx folder
this is what is written in their website
" For each dataset, each directory  segXX  contains a file  reference_CTA.txt  that contains the CTA stenoses detection and quantification reference standard. The files contain the world position of the x-, y-, and z-coordinate of each path point of the segment centerline"