Multiple Sites Ultrasonography of Peripheral Nerves in Differentiating Charcot-Marie-Tooth Type 1A from Chronic Inflammatory Demyelinating Polyradiculoneuropathy.

Jingwen Niu,Mingsheng Liu,Liying Cui

doi:10.3389/fneur.2017.00181

Abstract

Multiple sites measurement of cross-sectional areas (CSA) by ultrasound was performed to differentiate Charcot-Marie-Tooth type 1A (CMT1A) and chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). Nine patients with CMT1A, 28 patients with CIDP, and 14 healthy controls (HC) were recruited prospectively. Consecutive ultrasonography scanning was performed from wrist to axilla on median and ulnar nerves. CSAs were measured at 10 predetermined sites of each nerve. CMT1A had significantly larger CSAs at all sites of median and ulnar nerves (p < 0.01). In CMT1A, CSAs increased gradually and homogeneously from distal to proximal along the nerve, except potential entrapment sites. CIDP displayed three different morphological patterns, including mild enlargement in 15 patients, prominent segmental enlargement in 12, and slight enlargement in 1, among which different treatment responses were observed. All patients with mild nerve enlargement treated with intravenous immunoglobulin were responsive (7/7), while less than half of those with prominent segmental enlargement (3/7) were responsive (p < 0.01). Consecutive scan along the nerve and multiple sites measurement by ultrasound could supply more detailed morphological feature of the nerve and help to differentiate CMT1A from CIDP.

Highlights

Both Charcot–Marie–Tooth type 1A (CMT1A) and chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) are chronic demyelinating polyneuropathy involving motor and sensory nerve
The amount of enlargement was more prominent in CMT1 compared to CIDP, as evaluated by ultrasound pattern sum score (UPSS) [5], nerve size index (NSI) [4], or enlargement site number (ESN) [3]
Receiver operating characteristic (ROC) curve analysis was performed to evaluate the use of cross-sectional area (CSA) measurements to differentiate CMT1A from CIDP

Summary

INTRODUCTION

Both Charcot–Marie–Tooth type 1A (CMT1A) and chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) are chronic demyelinating polyneuropathy involving motor and sensory nerve. The amount of enlargement was more prominent in CMT1 compared to CIDP, as evaluated by ultrasound pattern sum score (UPSS) [5], nerve size index (NSI) [4], or enlargement site number (ESN) [3]. The description of overall enlargement at anatomical landmarks, the distribution of enlargement, and the pattern differences might help to differentiate acquired and inherited neuropathies [5]. These studies measured only two to five predetermined sites in one nerve, providing limited morphologic information for the whole nerve. By scanning the whole nerve and measuring cross-sectional areas (CSAs) in 10 consecutive sites in median and ulnar nerves, we got more accurate and thorough morphological information of the nerve

MATERIALS AND METHODS

RESULTS

DISCUSSION

ETHICS STATEMENT