Correlation of nerve ultrasound, electrophysiological and clinical findings in chronic inflammatory demyelinating polyneuropathy.

BACKGROUND AND PURPOSE: We present the nerve ultrasound findings in chronic inflammatory demyelinating polyneuropathy (CIDP) and examine their correlation with electrophysiology and functional disability.

METHODS: A total of 75 healthy controls and 48 CIDP patients underwent clinical, sonographic and electrophysiological evaluation a mean of 3.9 years(SD+/-2.7) after disease onset.

RESULTS: Nerve ultrasound revealed statistically significant higher cross-sectional area (CSA) values of the median (P<.0001), ulnar (P<.0001), radial (P<.0001), tibial (P<.0001), fibular nerve(P<.0001) in most of the anatomic sites and brachial plexus (supraclavicular, P<.0001;interscalene space, P = .0118),when compared to controls. The electroneurography documented signs of permanent axonal loss in the majority of peripheral nerves. A correlation between sonographic and electrophysiological findings was found only between the motor conduction velocity and CSA of the tibial nerve at the ankle (r = -.451, P = .007). Neither nerve sonography nor electrophysiology correlated with functional disability. The CSA of the median nerve in carpal tunnel and the ulnar nerve in Guyon's canal correlated with disease duration (P = .036, P = .027 respectively).

DISCUSSION: CIDP seems to show inhomogenous CSA enlargement in brachial plexus and peripheral nerves, with weak correlation to electrophysiological findings. Neither nerve sonography nor electrophysiology correlated with functional disability in CIDP patients. Multicenter, prospective studies are required to proof the applicability and diagnostic values of these findings.