Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP): MRI

Discussionby Dr MGK Murthy, Dr GA PrasadChronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is characterized clinically by a progressive or relapsing course of many months to years of symptoms similar to compressive myelopathy.Etiology Remains unknown, but T-cell activation in nerves plays an important role in the pathogenesis of CIDP& antigens in Schwann cells have been identified.PathologicallyCIDP is characterized by mononuclear cell infiltrates, edema, segmental demyelination, and remyelination&“onion bulb formation” which describes enlarged fascicles with increased endoneural connective tissues in which many myelinated fibers are surrounded by concentrically arranged  Schwann cells  that affects both nerve roots and peripheral nerves leading to nerve hyprtrophy.MRI Hypertrophy and abnormal enhancement of the cauda equina and lumbar spinal roots are seen. Involvement of cervical roots and the brachial plexus are rare& involvement ofintercostal nerves is also rare. Increased T2 signal intensity and the variable contrastenhancement of roots and nerve trunks reflect increased water content within the nerve fascicles and breakdown of the blood –nerve barrier, respectively. Gadolinium enhancement possibly suggests active disease.An elevated protein and low cell count in CSF sample, slowing/ block / prolonged distal latencies, and absence of waves or prolonged minimum f-wave latencies in electrophysiologicalstudies of nerve con...
Source: Sumer's Radiology Site - Category: Radiology Authors: Source Type: blogs