last year and got a sleep-deprived kind of test at the neuros. Goodness knows I'd have MRI's and nerve conductions out the ears...but in my case, I just keeled over in the house.
I believe they were checking for seizure potentials [I'd avoided all sleep tests prior to this, but had gotten almost all other tests]. OF course nothing came up.
It's a good thing that the emt's took a look at you tho. To check for TIA's and other possible cardiac wrinkles. [Went thru that myself too]

The only thing I've found that helps with the numbness is physical therapy. Various exercises help the rest of whatever nerves you have left, and your muscles re-program themselves to work with what there is left. Also helps you build up what strength you can to avoid falls in the future. It's not something you stop.....you have to keep at it.
IF you ask your docs [hopefully neuro?] for PT to help with the balance, I bet the doc will do a kind of "OH? I forgot about that!" And then write you PT orders...just be sure to ask for a 'home program'! That means the therapists give you exercises and some tools so you can do them at home, and keep it up after the therapy sessions end. Otherwise you do stuff at the PT's and no help for things to do on your own.
As one who has had many falls since getting PN, some very serious, I do NOT recommend that! PT and keeping at exercising in any ways possible to keep you moving is far better than the alternatives! - j