If your body does not work correctly and you are adding something potent such as HGH, yes its posible.
How bad has your vision deteriorated?
Don't wait to hear back from your Dr. just go to walgreens and buy a Blood Glucose kit!
Here is what I use when I am using GH and especially when I am adding IGF:
UltraMini Blood Glucose Monitoring System | OneTouch | Walgreens
Also, I am not saying ignore your dr. just take some initiave if your BG doesn't return to normal after 2 hours from eating than you are becoming type 2 diabetic and yes it would be from the GH! The good thing is that type 2 from GH usually reverses itself. But that wont help your eyesight!