Neuromuscular Ultrasound: A New Tool in Your Toolbox

Abstract

Neuromuscular ultrasound is a rapidly evolving technique for diagnosing, monitoring and facilitating treatment of patients with muscle and nerve disorders. It is a portable point-of-care technology that is non-invasive, painless and without ionizing radiation. Ultrasound can visualize muscle texture alterations indicating dystrophy or denervation, changes in size and anatomic continuity of nerve fascicles, and its dynamic imaging capabilities allow capturing of contractions and fasciculations. Ultrasound can also provide real-time guidance for needle placement, and can sometimes make a diagnosis when electromyography is not tolerated or not informative anymore. This review will focus on the technical and practical aspects of ultrasound as an imaging technique for muscles and nerves. It will discuss basic imaging principles, hardware and software setup, and provide examples of ultrasound use for visualizing muscle and nerve abnormalities with accuracy and confidence. The review is intended as a practical “how-to” guide to get started with neuromuscular ultrasound in daily practice.

Ultrasound versus electromyography for the detection of fasciculation in amyotrophic lateral sclerosis: systematic review and meta-analysis

“…Musculoskeletal ultrasound may add knowledge to neurophysiological test data by detecting changes in muscle morphology and echotexture that can imply denervation (30,31) . Ultrasound can also be utilized as a screening tool before submitting patients to procedures that are more invasive and painful, such as EMG and muscle biopsy (48,49) .…”

“…Ultrasound is a noninvasive, painless method that is more widely available than is EMG, as well as being less expensive and not involving the use of radiation (1,12,14,(26)(27)(28)(29)(30)(31) . However, ultrasound does not differentiate between benign (stable) and malignant (unstable) fasciculations.…”

Diagnostic Value of Muscle Ultrasound for Myopathies and Myositis

“…A particular property of muscles and tendons is anisotropy. In tissues that have colinear structures, the direction of sound reflection will change uniformly depending on the angle of insonation [3]. This has particular implications for imaging muscle as the echogenicity of the tissue can change with slight angulations of the probe.…”

Ultrasound can differentiate inclusion body myositis from disease mimics

“…System‐setting parameters were kept constant throughout the study, and scans were made using a strictly fixed preset and using protocols previously described for each center 3,13 . US images were analyzed using Quantitative Muscle Imaging Analysis (QUMIA, Radboudumc), a custom‐built software tool that allows for drawing regions of interest for gray‐scale histogram analysis and measuring muscle thickness with a digital caliper.…”

“…), who was not study blind. Given the 2 different US systems and setups, individual EIs cannot be compared between centers, 13 but the use of an otherwise standardized protocol does allow for comparing the results at a group level. JMP software version 13 (SAS, Inc, Cary, North Carolina) was used for statistical analysis.…”