Of course when they are deep, they are very easy to see, but it is often too late then.
No, No and No.
In the early stages, they can be very difficult to see according to my research. There is increasing evidence that they grow deeper and develop as we age, and a very recent article confirms this. In that study they claim 90% of high myopes have staphyloma of some degree. You will see prevalence estimates from <10% to 100% in the literature and this can be mostly ascribed to the difficulties in detection and the frank lack of knowledge of many retina specialists. I am not aware of OCT being used for staphyloma detection but I guess it could be used in that regard.
There is some very promising treatments coming regarding arresting the progression of staphyloma in myopic eyes directly. You can read a related post of mine yesterday. They could be some years away but they are coming almost definitely.
1. Yes
2. No B scan ultrasonography would work better than OCT
3. Yes
JCH MD