A subject close to my heart. Are you still searching for data / advice? I have been rather intermittent re logging on due traveling, hence delay in responding.
For the moment, take an increase in pain due to compression very seriously, and I do urge not going into pain control in this manner until more is known.
An expert will be aided in diagnosing the fault by a detailed description of the pain areas...i.e. the back of the calf, knee, toes etc..
Age is a major factor. Being a (very ) active person over many years is also very significant. All of this kind of thing would have to be known.
There is little to compare with a good MRI . Good means that the consultant is generally pleased with the results from that unit.
LR