Demyelinating nerve disorders affect the fatty protective covering (myelin) of human nerves and can cause disabling weakness and sensory loss. Myelin acts as a nerve insulator thereby helping in the fast transmission of impulses to the muscles. There are many causes of demyelinating nerve disorders – some of these are caused by the immune system attacking the nerve myelin sheath and thus are treatable by supressing the immune system. However, many of these nerve disorders are caused by genetic mutations which are not treatable. Intravenous immunoglobulin (IVIG) is a solution of human blood proteins and antibodies that is prepared from large pools of plasma collected from blood donors. IVIG forms the mainstay of treatment for patients with immune mediated demyelinating neuropathies. Other agents that supress the immune system also have a role in treatment resistant cases.
There are many criteria to diagnose the immune mediated nerve disorders, however misdiagnosis can be common. Thus some patients with undiagnosed genetic causes being unnecessarily exposed to toxic immune supressing drugs. In patients with immune mediated nerve disorders there is no test that helps predict response or guide ongoing treatment. There have been significant advances in using imaging technologies to study blood flow in the brain. Recently, there have also been some studies that have used MRI imaging techniques to study blood flow of nerves in certain nerve disorders. As blood flow changes with inflammation, study of these changes may help improve our understanding of immune mediated demyelinating nerve disorders. The aim of this study is to develop an ‘imaging biomarker’ to identify patients with genetic demyelinating neuropathies at the outset. This biomarker also has potential for use as a marker of disease activity and response to treatment. This will help in development of personalised treatment strategies for patients with immune mediated demyelinating nerve disorders.