It is just 3D volume, but I have an option load the series as multi-volume. The number and position of slices are the same, but number of slices can be different. To distinguish between these different images you can use the field Image Type, as I mentioned above, they are different for different images. Also, I tried to convert this series by mrtrix https://mrtrix.readthedocs.io/en/latest/reference/commands_list.html program and this program separates these images as different series which is the desired result, that’s why I suppose it is possible to upload these images as different series