I was reading the other night about someone with muscle fasciculations - the things we would normally refer to as spasms and which usually occur after treatment but when we mention them to clinicians they just smile and nod about.
Now these things are important because they evidence permanent damage, but they are very hard to prove because a) most of us don't sleep with our doctors, and, b) the blasted things disappear the second we try to evidence them on film.
However, this one person was sent by his doctor to a sleep centre and there they rigged him up to a machine which measured the number of fasciculations which occured throughout the night - in his case about 370 - this not only provided his doctor with evidence but also indicated where damage had occurred.
So, I don't know whether all sleep centres do this and I'm more or less certain an NHS doctor isn't going to send you, but it may be worth your while contacting a sleep centre, finding out if they do it and offering yourself up as a guinea-pig?