Nerve ultrasound: Ready for clinical practice?

Abstract

With the tremendous advance in technology, imaging methods have finally entered clinical routine for the assessment of the peripheral nervous system, after having already been employed for a long time in the realm of the central nervous system. Although both Ultrasound (US) and Magnetic Resonance Imaging (MRI) show good soft tissue resolution, US is more suited to everyday clinical practice, boasting easy accessibility, superior spatial resolution and low cost. MRI's main role lies with the imaging of deeper lying nervous structures and when US imaging is obscured by bony structures. Nerve US quantifies and anatomically pinpoints changes in nerve size and echotexture and is therefore useful for the identification of nerve entrapments, trauma, tumours and inflammation. It is also important for clinicians to realise that US imaging can reveal conditions even in the absence of significant neurophysiological abnormality. Furthermore, developments in nerve blood flow assessments have the potential for quantitating nerve blood flow, and thus providing new assessments of ischemic neuropathies.