3D Slicer and rek. file

Dear all,

I got a CT scan in the form of a single rek. file. I am unable to open in the Slicer. Is there any way to open/convert this data so I would be able to work on this scan in the Slicer?
Presumably this file type can be opened in the Dragonfly, so I guess it may be also possible in case of the 3D Slicer.

Thanks in advance!