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Modern neuromuscular electrodiagnosis (EDX) and neuromuscular ultrasound (NMUS) require a universal language for effective communication in clinical practice and research and, in particular, for teaching young colleagues. Therefore, the AANEM and the IFCN have decided to publish a joint glossary as they feel the need for an updated terminology to support educational activities in neuromuscular EDX and NMUS in all parts of the world. In addition NMUS has been rapidly progressing over the last years and is now widely used in the diagnosis of disorders of nerve and muscle in conjunction with EDX. This glossary has been developed by experts in the field of neuromuscular EDX and NMUS on behalf of the AANEM and the IFCN and has been agreed upon by electronic communication between January and November 2019. It is based on the glossaries of the AANEM from 2015 and of the IFCN from 1999. The EDX and NMUS terms and the explanatory illustrations have been updated and supplemented where necessary. The result is a comprehensive glossary of terms covering all fields of neuromuscular EDX and NMUS. It serves as a standard reference for clinical practice, education and research worldwide. HIGHLIGHTS: Optimal terminology in neuromuscular electrodiagnosis and ultrasound has been revisited. A team of international experts have revised and expanded a standardized glossary. This list of terms serves as standard reference for clinical practice, education and research.

Neuromuscular ultrasound is complementary to electrodiagnostic (EDx) testing and is useful in enhancing the diagnosis of mononeuropathies, peripheral nerve trauma, and demyelinating polyneuropathies. There is increasing interest in using ultrasound both to aid in the diagnosis of amyotrophic lateral sclerosis (ALS) and to monitor its progression. In this article we review the relevant literature on ultrasound in ALS. Ultrasound is more sensitive than EDx in identifying fasciculations in patients with ALS. It can detect decreased muscle thickness, increased muscle echointensity and echovariance, and reduced peripheral nerve size in these patients. Ultrasound is also a helpful tool in assessment of diaphragm function. Although additional studies are required to define the exact role of ultrasound in the evaluation and monitoring of ALS, it can improve the diagnostic yield in patients when ALS is suspected, but insufficiently supported, by clinical and EDx examinations. Muscle Nerve 60: 114-123, 2019.

Neuromuscular ultrasound (NMUS) is an accepted, but underutilized, diagnostic tool in the evaluation of neuromuscular disorders. The lack of uniform high-quality standards in published research and in clinical practice has been a limitation to its growth.In this article we address the shortcomings of NMUS research and establish basic standards to guide further work in the field.A review of the basic types of NMUS research studies is presented, along with the elements that each should include. Basic standards for this imaging technique are also presented. An explanation of common data elements (CDEs) is provided with discussion of how NMUS may benefit from their creation.High-quality NMUS research is needed to advance the field. Assuring that publications meet basic standards is essential. In addition, the creation of CDEs specific for NMUS is proposed. Muscle Nerve 56: 375-378, 2017.

INTRODUCTION:Reference values (RVs) are required to separate normal from abnormal values obtained in electrodiagnostic (EDx) testing. However, it is frequently impractical to perform studies on control subjects to obtain RVs. The Extrapolated Reference Values (E-Ref) procedure extracts RVs from data obtained during clinically indicated EDx testing. We compared the E-Ref results with established RVs in several sets of EDx data. METHODS:The mathematical basis for E-Ref was explored to develop an algorithm for the E-Ref procedure. To test the validity of this algorithm, it was applied to simulated and real jitter measurements from control subjects and patients with myasthenia gravis, and to nerve conduction studies from patients with various conditions referred for EDx studies. RESULTS:There was good concordance between E-Ref and RVs for all evaluated data sets. DISCUSSION:E-Ref is a promising method to develop RVs. Muscle Nerve 57: 90-95, 2018.

At our institution, core muscle biopsies are performed on muscles selected using electromyography (EMG). Ultrasound (US) guidance is not used routinely. The aim of this study was to determine if US guidance of EMG selected muscles would increase the diagnostic yield of the biopsy as compared to the current practice standards.Two trained physicians performed 40 randomized biopsies (US guided or traditional approach). The amount of tissue obtained in each biopsy was recorded (volume and mass), along with the final pathologic diagnosis in each case and incidence of complications.Forty patients were studied. Sixteen muscle biopsies were done with US guidance; 50% had a definitive diagnosis, and 38% did not. In the non-US guidance group, 58% had a definitive diagnosis, and 33% did not.US did not provide any additive advantage when used to guide biopsy in a muscle previously selected for biopsy with EMG. Muscle Nerve 54: 786-788, 2016.

Mycophenolate mofetil (MMF) is frequently used to treat myasthenia gravis, but there is little information to guide clinicians on the safety of reducing the dose in well-controlled patients.This retrospective chart review at 3 institutions identified 92 patients who had undergone MMF taper after achieving either pharmacologic remission or minimal manifestations status. Statistical analysis was performed to assess differences in patient characteristics between patients who had successfully tapered MMF and those who relapsed.Of 92 patients undergoing a taper, 30 relapsed. The relapses were mild, transient, and usually responded to increased MMF dose. MG crisis did not occur. The mean dose at time of relapse was 888 mg/day. Patients with relapses were tapered more quickly (8.4 vs. 62.4 months).Tapering MMF appears safe after years of disease stability. Reducing the dose at a dose of only 500 mg/day every 12 months is recommended.

Acetylcholine receptor (AChR) and striated muscle antibodies (StrAbs) are found frequently in myasthenia gravis (MG) patients with thymoma. In this study we aimed to determine the positive predictive value (PPV) and negative predictive value (NPV) of these antibodies for thymoma in patients with MG.Antibody findings, thymic histology, and onset age were reviewed for 1141 patients with MG. PPV and NPV of these antibodies for thymoma were determined.The PPV of AChR binding antibodies plus StrAbs was highest (50.0%) with onset before the age of 40 years. The PPV of all antibodies was low (9%) after age 40. Higher StrAb levels did not increase the PPV. The NPV of AChR binding antibodies was high (99.7%) for all ages.Patients without AChR binding antibody are not likely to have a thymoma. StrAbs and AChR binding antibodies are not diagnostic for thymoma, but in early-onset MG their presence should raise the clinical suspicion for thymoma.

Current standards for diagnosing polyneuropathies (PN) and motor neuron disease (MND) sometimes lack early sensitivity and result in delayed diagnosis and treatment. Neuromuscular ultrasound (NMUS), already established in the diagnosis of entrapment neuropathies, may offer another means of diagnosis and monitoring response to therapy. This review of current evidence discusses diffuse nerve hypertrophy in hereditary demyelinating neuropathies, multifocal nerve enlargement in acquired demyelinating PN and the lack of readily apparent structural change in axonal neuropathies. NMUS detection of fasciculations and muscular change in MND is also reviewed, along with the need for further research to better define the role of nerve imaging in patients with PN.

Neuromuscular ultrasound (NMUS), an emerging diagnostic subspecialty field, has become an important extension of the electrodiagnostic examination. However, there are no formal guidelines on how to appropriately report NMUS results.The AANEM convened an expert panel to develop recommendations for reporting NMUS findings.Providers should describe the reason for referral, the nerves or muscles studied, and normal values as well as numerical values for the results of imaging. Muscle imaging reports should also include a description of how gray-scale values were calculated. NMUS-guided needle placement reports should include a description of the length and gauge of needle, the type of probe used, and an indication of how well the patient tolerated the procedure. All reports should clearly state whether the findings were normal or abnormal and include a definitive diagnosis.NMUS reports should provide comprehensive information along with a succinct conclusion, mirroring guidelines for electrodiagnostic reports.

Diabetic polyneuropathy (DPN) is increasingly prevalent in the USA, but nerve ultrasound (US) findings have not been assessed systematically. Our aim was to establish the sonographic characteristics of lower extremity nerves in DPN and correlate them with electrodiagnostic (EDx) findings.Consecutive patients (n = 25) with evidence of DPN and 25 patient controls without DPN underwent blinded US imaging of the fibular and sural nerves. Nerve cross-sectional area (CSA), diameter and echogenicity were recorded.There were no differences in fibular or sural nerve CSA, diameter, or echogenicity between the 2 groups. No correlations between nerve CSA and EDx studies were found. In DPN, there were moderate inverse correlations with age (r = -0.44 sural ankle, r = -0.39 sural leg, r = -0.45 fibular ankle).US measurements of lower extremity nerves in DPN do not differ from controls or correlate with EDx findings. Novel US techniques and/or pedal nerve US may be necessary to detect differences.

Introduction: The purpose of this study was to develop an evidence-based guideline for the use of neuromus- cular ultrasound in the diagnosis of carpal tunnel syndrome (CTS). Methods: Two questions were asked: (1) What is the ac- curacy of median nerve cross-sectional area enlargement as measured with ultrasound for the diagnosis of CTS? (2) What added value, if any, does neuromuscular ultrasound provide over electrodiagnostic studies alone for the diagnosis of CTS? A systematic review was performed, and studies were classified according to American Academy of Neurology criteria for rating articles of diagnostic accuracy (question 1) and for screening articles (question 2). Results: Neuromuscular ultrasound mea- surement of median nerve cross-sectional area at the wrist is accurate and may be offered as a diagnostic test for CTS (Level A). Neuromuscular ultrasound probably adds value to electrodiagnostic studies when diagnosing CTS and should be considered in screening for structural abnormalities at the wrist in those with CTS (Level B). Muscle Nerve 46: 287-293, 2012

Sonographically measured median nerve cross-sectional area (CSA) at the wrist is increased in patients with carpal tunnel syndrome (CTS). Ultrasound of the median nerve may be useful in screening for electrodiagnostic (EDx) abnormalities.EDx studies were performed on all participants. Sonographic evaluation of median nerve CSA at the wrist and in the forearm was performed by a physician blinded to the EDx results. Multivariate and receiver operating characteristic (ROC) analysis were used to assess the data.Fifty control wrists and 192 symptomatic wrists were analyzed. Sensitivity of ultrasound in excluding EDx abnormality was 99% for CSA of 9 mm(2) and 97% for a wrist-forearm ratio (WFR) of 1.4. There was no clinically significant correlation between ultrasound parameters and EDx severity.Median nerve ultrasound is a highly sensitive screening tool for EDx abnormality, but it cannot determine severity. This may lead to changes in the current standards for evaluating CTS.

Ultrasonographic (US) enlargement of the median nerve at the wrist is known to be consistent with carpal tunnel syndrome (CTS), although the effects of different measurement techniques, equipment, and patient populations remain unknown. The purpose of this study was to examine the similarities and differences of US findings in CTS between two electromyography (EMG) laboratories. In 2006 and 2007, US measurements of the median nerve were recorded independently and statistically analyzed in patients with CTS at two EMG laboratories (Duke University, Durham, NC, USA, and Università Cattolica del Sacro Cuore, Rome, Italy). Patient age, median nerve area in the forearm, and neurophysiologic score did not differ significantly between the two laboratories. The North Carolina group had a larger median nerve area at the wrist and wrist-to-forearm ratio than the Italian group, although both were elevated in reference to established values for the diagnosis of CTS. Median nerve US is less susceptible to differences between laboratories than previously thought, permitting greater generalization of findings.