Hi,
I had the "halo" on two occaisions. The only pain you might feel is the initial needle that sedates the area - and if the doctor is good at this, he masks that pain as well - but it is literally two seconds.
After the procedure, I had no pain, slept well and went out shopping the next day.
So, it looks scary, but was trivial for mr.
Good luck to your Mom.
Mary