I'm not an expert, nor in the medical profession, so my comments are based on personal experience and what I've learned from reading many medical journals online and consulting with my Uro in the V.A.
I have a moderate VL and have tried everything this side of an implant and nothing helped until I discovered penis exercises. These exercises consist of various ways to stretch and squeeze your penis (internally/externally). All done in timed intervals/repetition, like working out at the gym...but focus is on your dick. Some people use devices to aid the process; penis weight hangers for consistent stretches and clamps/for inner pressure expansion. These exercises have been mocked and ridiculed for a long time, by both the medical profession and others...I have discovered that 100% of them have either never tried them, or started out overly ambitious and injured themselves.
These exercises are not a cure for VL nor ED, however, they works wonders for maintenance. Sometimes I get very weary from doing them on a daily basis and think of them as a pain-in-the-butt chore. But if I don't keep my dick this active manually...the VL shows it's ugly head again, which is unacceptable.
Penis exercises have been my remedy for good boners since 2010. Now all I need is an 'O' ring from Ace Hardware and Cialis...boners for days! I have recovered almost 90% function, gained in size and it's appearance is heavy and muscular now. Viva la Dick!