Venous Leakage Vs Nerve Damage

The question is how do you tell the difference between nerve damage and a venous leak. With both you might not get night wood so that doesn’t tell you anything other than you have ED. Can anyone tell me how you can tell the difference between a venous leak and nerve damage?

If you have venous leakage you can get very soft erections. If you wear a tight cock ring and get a good erection then you know it is venous leakage. Use a 1” wide section of a bicycle inner tube for a cock ring if you don’t have one. MXL