Chronic Inflammatory Demyelinating Polyradiculopathy (CIDP)-MRI

Clinical history: 36 year old female. Neck pain, radiating to left side. No other constitutional symptoms.

Provisional MR diagnosis: CIDP under evaluation

Teaching points by Dr MGK Murthy, Dr Praveen Jha

1. Chronic Inflammatory Demyelinating Polyradiculopathy (CIDP) is a treatable, relapsing,immune mediated disorder  and is  a fashionable terminology amongst the radiologists using MR Neurography. Clinically presents  with peripheral sensory neural deficits  with NCVs suggesting acquired demyelinating polyneuropathy and EMGs showing  Active denervation with Laboratory including CSF unhelpful

2. MRI/Neurography  usually shows  symmetrical high signal on STIR and enlargement of brachial plexus. Symmetricality  with High signal intensity of nerve roots and beyond (  Ref- sternocleidomastoid muscle  signal)  is more  a reliable sign as compared to increased diameter and thickening of brachial plexus  as such  (European Federation for Neurological Diseases (EFND) criterion for probable/ definite  CIDP refers)

3. Steroids and Intravenous Immunoglobulins form the mainstay for therapy. Though  many believe MR findings persist even after symptoms improve  and hence should not be used for  Prognostication, some believe persistence of findings   may   suggest refractoriness to immunomodulation. .Long term (of decades)  follow up shows  secondary axonal degeneration , leading to MRI  pictures suggesting  Atrophy

4. MRI findings can not differentiate  the Clincial mimics of CIDP including  MMN (multifocal motor neuropahty) which shows asymmetry and no sensory loss on clinical  examination .