IG-SRT in NYC? IG-SRT 100 vs IG-SRT 100 Vision?

I'm investigating treatment for basal cell carcinomas on nose and face. 3 dermatologists at a major NYC Manhattan hospital did not mention IG-SRT as an option, nor did they even know about it. How could that be?? But I did find places in New Jersey. Are there any drs/hospital in NYC that offer this? And is SRT the same as IG-SRT? And is the newer version of the machine-Sensus SRT 100 Vision much better that the older Sensus SRT 100? Thanks for any clarification/tips.