How is Motor Neurone Disease Diagnosed?
If the G.P. believes that you could be affected by a neurological problem they should normally refer you to a specific neurology department. From there you will have a series of tests including those listed below. Dependent on your symptoms you may need other tests and may not need all those listed here.
You may be given blood tests, these are designed to look for any increase in your creatinine kinase. This is a product of muscle break down and is sometimes present in the system of patients suffering from Motor Neurone Disease. This is not a specific indicator for MND and could also be a sign that one of a number of other medical problems may be present.
The EMG test is also sometimes referred to as a ‘needle test’, this is because very slim needles are used to measure the nerve impulses which naturally occur within certain specific muscles in the body. Readings are normally recorded from each of your limbs as well as the muscles of the throat (the bulbar muscles). If any of your muscles have damage to their nerve connection this can then be detected as the electrical activity within them is very different from that of more typical (more healthy) muscles. The EMG can also register an abnormal reading even if those actual muscles have not yet been affected. For this reason it is an incredibly useful part of the diagnostic process when looking for signs of MND.
Nerve Conduction Tests
These tests might be done whilst an EMG is being taken. Electrical impulses are applied via a conductive patch attached to the skin; this is then used to measure the rate at which the nerves in your body transmit these electrical signals and allows abnormalities to be shown.
Transcranial Magnetic Stimulation (TMS)
TMS is a relatively new test that may sometimes be done simultaneously with the nerve conduction test. Its purpose is to check the amount of activity occurring within the upper motor neurones. Results from this test contribute to the overall process of diagnosis.
Magnetic Resonance Imagery (MRI) Scans
This test can be very intimidating as it involves being enclosed within a cylindrical machine while the images are taken, however it is harmless. The MRI machine takes magnetic images which are like a photograph of the internal structure of your body using a series of powerful electromagnets. An MRI Scan can be used to identify the damaged areas which are caused by factors such as strokes, Multiple Sclerosis, Alzheimer’s disease, Parkinson’s disease, tumours present in the body because of cancer or other benign sources, and trapped nerves in addition to indicating any damage within the spine or brain which has been caused by some physical injury.
An MRI scan does not diagnose Motor Neurone Disease, the damage which MND causes will not be shown up on an MRI scan. However it can be used as a method for ruling some other diseases or conditions which may present with similar symptoms to MND.
Your neurologist might want you to have further tests like lumbar punctures or muscle biopsies should the findings from the other tests indicate that they will be of use, however these are not used as a matter of course when looking into a possible case of MND.
At every step of the way your doctors should explain exactly what is going on and what to expect. If you are unclear about anything you should always ask and they will be happy to go through it with you.