And the results are in

The  other day I had a follow up appointment with the ENT, following my VEMP testt last month.  It would seem that the VEMP test backs up the findings of the CT scan, and confirms the diagnosis of Superior Semi circular canal dehiscence.  It also suggests that I am bilateral, ie have a hole in the canal in both ears. 

This all means that they consider me a candidate for surgery.  In the UK that pretty much exclusively means that surgery will be done by the Trans-Mastoid approach, and the hole itself will either be patched or plugged.  Let me explain this a little further. 

There are two surgical techniques that are used to fix SCDS.  One approach is Mid-fossa Craniotomy, which is a very invasive procedure, which involves making an incision through the skull and coming at the hole from the top down.  The plus side of this is that they can see the hole, the downside is that due to the invasive nature there are extra risks involved. 

The second approach is the Trans Mastoid approach, where they come into the inner ear through the mastoid bone behind your ear.  This is less invasive, it does not require having to lift the brain, and therefore carries less risk.  But the downside is that they cannot visualise the dehiscence.  The Transmastoid approach is the technique that is used in the UK.  The US uses both techniques. 

Once they have gained access to the inner ear, there are two ways of fixing it.  They can either put a patch over the hole, or plug the entire canal.  Putting a patch over the hole would maintain the function of the canal, but it is not as durable as plugging, and if it is not in the right place, then the surgery will fail.  Plugging the canal, is where they fill the canal with a sealing substance, and therefore seals the hole.  But by plugging the canal you lose the function of the canal, which could affect balance.  However, with Vestibular therapy, it is hoped that they brain learns to compensate for that loss.

As you can see, it is not straightforward, and there will be various decisions to be made.  The first decision for me, was getting a surgeon who had done this procedure before.  As nice my ENT consultant was, he admitted he hadn't done this surgery as a consultant before, and I really didn't fancy being the first.  So I am being referred to a consultant who has a few of these surgeries under his belt.  The problem with having a rare condition that has only been known about for the last 20 years, is that even the experts are still learning about the condition, and not that many surgeries (in the scale of things) have been undertaken.  Techniques are being improved upon all the time, and the longevity of the surgeries is still being discovered.

That being said, I have a condition that has a chance of being fixed.  I have a chance of getting my pre-SCDS life back. So I await surgery. 

More tests

I realise that I need to bring you up to date. 

I went to see the different ENT at the end of October, and this was the first time I felt that I was talking to a medical person who knew anything about this condition.  I was in a room with the ENT, a physio, and various other nurses who between them all made up the balance clinic.  Unfortunately the ENT didn't have access to the reformatted version of my CT scan, but he later wrote me a letter saying that once he had seen it, it became clear that I "had quite a good example of superior semi-circular canal dehiscence". 

Another test he wanted to have done on me was a VEMP test.  VEMP stands for "vestibular evoked myogenic potential".  Which to the lay person means absolutely nothing!  I tried researching it, so that I knew what to expect and to try to understand the purpose of the test.  Unfortunately I was unable to make head nor tail of my findings.  I gleaned that it involves electrodes and a pulsating noise in your ear, but the whys and wherefores of it all remain a mystery. 

So the day came to go for my test.  It was explained to me that the vestibular system is a complex system, and trying to find out where it is going wrong is like trying to find a needle in the haystack.  VEMP testing combined with high resolution CT scan  is used as a diagnostic tool in diagnosing SCDS.  And even though I have had it done now, I still don't understand it, so all I can do is explain the process.

I was hooked up to some electrodes.  Two each side of my neck, placed on specific muscles.  I had further electrodes placed on the front of my neck, and my forehead.  The electrodes were tested, and retested, and then moved around, until after what seemed like forever, they were happy that they were set up correctly.  I then had to turn my head one way, to put my neck muscle under just the right amount of tension, which was determined by a traffic light type arrangement.  Red meant that it was contracted too much, blue was not enough, and green was just right.  They then, through and ear piece placed in my ear, sent a loud pulsating noise.  This made my eyes bounce all over the place, but I had to concentrate on keeping my neck in the correct position.  I had this repeated on the other side (which was much harder as  couldn't maintain the correct tension in my neck).  Then the test was repeated on each side again but at a lower sound level. 

I was expecting to feel particularly disorientated after all that, but I think the overwhelming feeling was one of tiredness, and a slightly sore neck!! 

The results of the test will be analysed over the next couple of weeks, and hopefully, when I get to see the consultant again in December, we will be able to formulate a plan of action to rid me of the symptoms of this condition.