Slicer can now display volume rendering directly in the HoloLens2. The huge advantage of augmented reality headsets compared to 3D displays is that you can place the volume inside the patient at the correct physical location and use it for guidance. Simply manually aligning the visible skin surface can be sufficiently accurate for larger, superficial targets. There are software libraries for automatic alignment and more accurate tracking, but those are not yet integrated into Slicer.