im experimenting with mri segmentation . sometimes it works fine but started to get this error more often . when i draw or pain i get some area segmented some are not .
I wonder if your segmentation geometry has very large voxels, and your slice view is grazing these from an oblique angle. Something like the second figure at this link: https://lassoan.github.io/SlicerSegmentationRecipes/ObliqueSliceSegmentation/