Nerve ultrasound may be considered in cases with high clinical suspician for a chronic inflammatory neuropathy and hereditary demyelinating neuropathy (CMT1) complementary to EMG, as screening tool to aid in their identification. Nevertheless the clinical prediction rule guides main clinical diagnostic strategies. Ultrasound offers an important alternative for MRI. In contrast to MRI, ultrasound is broadly available and is a practical bedside imaging tool that allows efficient investigation of multiple nerves (flexible field of view vs fixed bij MRI). Also in contrast to MRI,  objective cut-offs improve its reliability to determine whether nerve size is abnormal. MRI may in part compensate for this with addition of signal intensity (hyperintens on T2, alo subjective evaluation by (neuro)radiologist)). In a subgroup of patients with CIDP and MMN this may even be the only positive test, indicating the imporant added value of nerve ultrasound. In neuropathy with IgM MGUS (+/- anti-MAG), a pattern of diffuse nerve enlargement can be seen mirroring that of CIDP.. Also in vasculitic neuropathy (systemic & non-systemic (single organ peripheral nerve vasculitis) multifocal enlargements of peripheral nerves can be seen, brachial plexus is usually spared and part of these enlarged nerves also exhibit hypervascularisation. In case of (non-systemische) vasculitic neuropathy, it could be useful to include sural nerve, to aid in selection of nerve for biopsy which appear to further increase the yield of biopsies. Finally, multifocale multifocal nerve enlargements and/or plexus involvement has also been described in  amyotrophic neuralgia and diabetic plexo-neuropathy, neurolymphomatosis, neurofibromatosis (often prominent neurofibromas in enlarged nerve(root)s).

Ultrasound can accurately identify patients with chronic inflammatory neuropathy, however EMG remains gold standard and also needed to discriminate between subtypes.

Clinical prediction rule is main guide for adequate interpretation of nerve ultrasound findings, in appropriate clinical context the PPV & NPV are high.