Update 29 - Information on CIDP (Part 1)

I have recently found a video specifically about CIDP, from an expert in this field:

Richard J. Barohn, M.D. - Chair, Dept. of Neurology, University of Kansas Medical Centre

Below is a synopsis of the first part of this hour long video, presented in November 2012, to a audience of medical experts.  It has taken me around 3 hours to de-crypt some of the terms and slides used (so far).

Apologies if I have made this too technical, but I have tried my best to make it understandable.

If you want to watch the full version it is available @ http://www.gbs-cidp.org

What is CIDP

Q: What pattern of Neuropathy specifically defines a sufferer from CIDP?

A: Symmetric proximal and distal weakness with sensory loss

Explanation: Muscle weakness away from the core of the body (i.e. in the arms &/or legs) with loss of feeling within those same limbs. The weakness & loss of feeling being the same down both sides of the body (left and right)

If you just have loss of feeling - this can be caused by other issues (e.g. Diabetes)

If it is not the same on both sides, these are other conditions linked to CIDP/GBS.

How to prove it is CIDP

Q: What is the best test for CIDP?

A: Nerve conduction studies (NCS)

Explanation: There are two types of nerves Motor (control movement) and sensory (control feeling). Both can be tested to see how fast they react to an electrical stimulation. This measures the speed it takes for the signals to get from the one place to another (latency measured in milliseconds) and is performed in a hospital or clinic.

Though a Lumbar Puncture can also be used (CerebroSpinal Fluid - CSF, or Spinal Tap), this measures the levels of proteins found in the spine and is another good indicator of CIDP if they are high,  the presentation states that this backs up the NCS findings

What NCS Values point to CIDP?

 Below is a table taken from one of the slides which just proves how complex and difficult medical people seem to want to make it for the ordinary person in the world to understand what they are saying!

Explanation (I hope!):

NCV - Nerve Conduction Value (metres per second)
DL - Distal Latency (signal travel time between 2 points)
F Waves - time for signal to travel back to central nervous system
LLN - Lower Limit of Normal (you've got to love them!)
ULN - Upper Limit of Normal

Location of Nerves:

So for each of the different nerves in the arm, the NCV needs to be less that 33.6 metres/second (<70%) for them to be fairly certain it is CIDP, with the norm being 48. In the legs this is 29.4 against 42.

For the Median nerve in the arm the time needs to be over 6.7 milliseconds (>150%) against the norm of 4.5 and the Ulnar is 5.4 to 3.6 (why these are different I don't know - I presume they have to be different lengths).  In the legs they are the same at 9.9 against 6.6 milliseconds.

The Time for the signal to travel back to the central nervous system is different for all @ Median: 46.5 to 31, Ulnar: 48 to 32, Peroneal: 84 to 56 and Tibial 87 to 58.

I am now going for a lie down to recover and will put more on this presentation up later!!