My urologist said Spare OAR and Barrigel placements are quite commonly used.

It appears to vary with the practice setting and the practitioner. My hometown radiologist (who delivered the IMRT) was rather noncommittal regarding a spacer. The radiation oncologists involved with my brachytherapy procedure were proponents of spacer use. There's yet another, newer spacer on the market called Bioprotect. That's the one that I had implanted concurrent with the brachytherapy.