“…However, direct and objective comparisons are difficult to achieve due to following two issues: 1) Different MR data sets acquired with different image acquisition protocols are used in different studies, and most of these MR data sets are not publicly available. Although there exists one open data set for comparing algorithms for clinical vertebral segmentation from 3D CT data (Yao et al, 2016), to the best of our knowledge, there exists only one open MR data set with the associated manual delineation of IVDs (Oktay and A C C E P T E D M A N U S C R I P T Akgul, 2013). This open MR data set, however, cannot be used to evaluate and compare 3D IVD localization and segmentation algorithms, as only 2D mid-sagittal slices are available in the data set; and 2) Different evaluation metrics are used in different studies, which precludes the possibility of direct comparison.…”