Neuromuscular ultrasound standardized scanning techniques and protocols: Expert panel recommendations.

Neuromuscular ultrasound has become an integral part of the diagnostic workup of neuromuscular disorders at many centers. Despite its growing utility, uniform standard scanning techniques do not currently exist. Scanning approaches for similar diseases vary in the literature creating heterogeneity in the studies as reported in several meta-analysis. Moreover, neuromuscular ultrasound experts including the group in this study have different views with regards to technical aspects, scanning protocols, and the parameters that should be assessed. Establishing standardized neuromuscular scanning protocols is essential for the development of the subspeciality to ensure uniform clinical and research practices. Therefore, we aimed to recommend consensus-based standardized scanning techniques and protocols for common neuromuscular disorders using the Delphi approach. A panel of 17 experts participated in the study, which consisted of three consecutive electronic surveys. The first survey included voting on six scanning protocols addressing the general scanning technique and five common categories of suspected neuromuscular disorders. The subsequent surveys focused on refining the protocols and voting on new steps, rephrased statements, or areas of non-agreement. A high degree of consensus was achieved on the general neuromuscular ultrasound scanning technique and the scanning protocols for focal mononeuropathies, brachial plexopathies, polyneuropathies, amyotophic lateral sclerosis, and muscle diseases. In this study, a group of neuromuscular ultrasound experts developed six consensus-based neuromuscular ultrasound scanning protocols that may serve as references for clinicians and researchers. The standardized protocols could also aid in achieving high-quality uniform neuromuscular ultrasound practices.

Virtual neuromuscular ultrasound courses during COVID-19 pandemic: Leveraging technology to enhance learning opportunities.

INTRODUCTION/AIMS: Hands-on supervised training is essential for learning diagnostic ultrasound. Unfortunately, the coronavirus disease 2019 (COVID-19) pandemic led to suspension of in-person training courses. As a result, many hands-on training courses were converted into virtual courses during the pandemic. Several reports regarding virtual ultrasound courses exist, but none has addressed virtual neuromuscular ultrasound courses, their design, or participants' views of this form of training. Therefore, the aims of this study were: (1) to determine the feasibility of conducting virtual neuromuscular ultrasound courses during the COVID-19 pandemic; and (2) to report the positive and negative aspects of the courses through the analyses of the responses of post-course surveys. METHODS: Two virtual neuromuscular ultrasound courses, basic and intermediate level, were conducted by the Egyptian Neuromuscular Ultrasound society during August 2020. Post-course, the attendees were directed to an electronic survey that consisted of eight questions. Ninety-three responses (23.8%) were obtained from the survey of the basic course and 156 responses (44.4%) were obtained from the survey of the intermediate course. RESULTS: Ninety-eight percent of the respondents to basic course surveys, and 100% of the respondents to the intermediate course survey found the courses useful or very useful. DISCUSSION: This report demonstrates the utility of virtual neuromuscular ultrasound courses for those participants willing to respond to a survey and describes a proposed design for such courses. Although hands-on supervised ultrasound training is ideal, virtual courses can be useful alternatives to in-person training when in-person interaction is restricted.

Neuromuscular ultrasound competency assessment: Consensus-based survey.

Neuromuscular ultrasound is a rapidly evolving specialty with direct application for patient care. Competency assessment is an essential standard needed to ensure quality for practitioners, particularly for those newly acquiring skills with the technique. Our aim was to survey experts' opinions regarding physician competency assessment of neuromuscular ultrasound and to identify minimal competency of knowledge and skills. The opinions of 18 experts were obtained through the Delphi method using two consecutive electronic surveys. A high degree of consensus was achieved on items regarding framework and the conduct of neuromuscular ultrasound assessment and the knowledge and skills that a candidate needs to attain minimal competency in neuromuscular ultrasound. In this study, a group of neuromuscular ultrasound experts developed a general framework for neuromuscular ultrasound competency assessment and recommended testable areas of knowledge and skills suitable for establishing minimal competency.

Guidelines for neuromuscular ultrasound training.

Neuromuscular ultrasound has become an essential tool in the diagnostic evaluation of various neuromuscular disorders, and, as such, there is growing interest in neuromuscular ultrasound training. Effective training is critical in mastering this modality. Our aim was to develop consensus-based guidelines for neuromuscular ultrasound training courses. A total of 18 experts participated. Expert opinion was sought through the Delphi method using 4 consecutive electronic surveys. A high degree of consensus was achieved with regard to the general structure of neuromuscular ultrasound training; the categorization of training into basic, intermediate, and advanced levels; the learning objectives; and the curriculum for each level. In this study, a group of neuromuscular ultrasound experts established consensus-based guidelines for neuromuscular ultrasound training. These guidelines can be used in the development of the specialty and the standardization of neuromuscular ultrasound training courses and workshops.

Statin Pretreatment and Microembolic Signals in Large Artery Atherosclerosis.

Background and Purpose- Scarce data indicate that statin pretreatment (SP) in patients with acute cerebral ischemia because of large artery atherosclerosis may be related to lower risk of recurrent stroke because of a decreased incidence of microembolic signals (MES) during transcranial Doppler monitoring. Methods- We performed a systematic review and meta-analysis of available observational studies reporting MES presence/absence or MES burden, categorized according to SP status, in patients with acute cerebral ischemia because of symptomatic (≥50%) large artery atherosclerosis. In studies with partially-published data, authors were contacted for previously unpublished information. We also performed a sensitivity analysis of studies with data on MES burden categorized according to SP status, and an additional subgroup analysis in patients receiving higher-dose SP (atorvastatin 80 mg or rosuvastatin 40 mg daily). Results- Seven eligible study protocols were identified (610 patients, 54% with SP). SP was associated with a reduced risk of MES detection during transcranial Doppler monitoring (risk ratio=0.67; 95% CI, 0.45-0.98), with substantial heterogeneity between studies ( I2=52%). In studies reporting MES burden (n=4), a significantly lower number of MES were identified in patients with compared with those without SP (mean difference=-0.92; 95% CI, -1.64 to -0.19), with no evidence of heterogeneity between studies ( I2=49%). Subgroup analysis revealed that higher-dose SP reduced the risk of detecting MES (risk ratio=0.23; 95% CI, 0.06-0.88), with no evidence of heterogeneity between studies ( I2=0%). Conclusions- SP seems to be associated with a lower incidence and burden of MES in patients with acute cerebral ischemia because of large artery atherosclerosis.

Ultrasound visualization of nerve remodeling after strenuous exercise.

INTRODUCTION: The aim of this case study is to describe the use of nerve ultrasound to visualize the morphological changes that occur during conduction velocity alterations after strenuous exercise. METHODS: A 32-year-old, healthy runner underwent clinical, electrophysiological, and ultrasound evaluation 24 hours before, 30 minutes after, and 24 hours after a marathon. RESULTS: An increase in motor conduction velocity of the median, ulnar, radial, and tibial nerves and sensory conduction velocity of the median and ulnar nerves was found between pre- and post-marathon studies. An increase in the cross-sectional area of the median (carpal tunnel), ulnar (Guyon canal and elbow), fibular (fibular head), and tibial (ankle) nerves was documented. No changes in the MRC sum scale score of the various peripheral nerves were detected. CONCLUSION: The case described shows the morphological changes that occur in healthy peripheral nerves during conduction velocity alterations.

Nerve ultrasound protocol in differentiating chronic immune-mediated neuropathies.

INTRODUCTION: In this study we evaluated a new neuropathy ultrasound protocol (NUP) for differentiating chronic immune-mediated neuropathies. METHODS: The NUP was evaluated in 110 patients with clinical presentations of chronic immune-mediated neuropathy. All patients were first evaluated clinically and electrophysiologically and divided into 4 polyneuropathy groups: (a) symmetric demyelinating; (b) symmetric axonal; (c) asymmetric demyelinating; and (d) asymmetric axonal. During step 2, the NUP was evaluated prospectively for all 4 study groups. RESULTS: Overall, the NUP led to correct classification in 42 of 49 (85.7%) patients with chronic inflammatory demyelinating polyneuropathy (CIDP), 13 of 15 (86.9%) with multifocal motor neuropathy (MMN), and 5 of 5 (100%) with multifocal-acquired demyelinating sensory and motor neuropathy (MADSAM). The NUP had >80% sensitivity and specificity in distinguishing CIDP, MMN, and MADSAM in all 4 study groups. CONCLUSIONS: The NUP is a useful addition in the differential diagnosis of chronic immune-mediated neuropathies in everyday practice. Muscle Nerve 54: 864-871, 2016.

Facing the diagnostic challenge: Nerve ultrasound in diabetic patients with neuropathic symptoms.

INTRODUCTION: We describe the nerve ultrasound findings in patients with type II diabetes mellitus who have neuropathic symptoms and signs. METHODS: Fifty-five healthy controls and 44 diabetic patients underwent clinical, sonographic, and electrophysiological evaluation. Patients were studied at a mean of 14.3 years after disease onset. RESULTS: Nerve ultrasound revealed increased cross-sectional area (CSA) in peripheral nerves at compression sites (although no clinical symptoms were present) and noncompression sites. No correlation was detected between sonographic and electrophysiological findings. A CSA increase of the tibial nerve in the popliteal fossa was detected in 5 patients with neuropathic symptoms, although electrophysiology was normal. CONCLUSIONS: Nerve ultrasound revealed crucial morphological alterations in diabetic patients. CSA enlargement at compression sites indicates subclinical nerve affection and may indicate susceptibility to entrapment syndromes. CSA increase at noncompression sites despite normal electrophysiology suggests early morphological abnormalities. Further longitudinal studies are required to confirm our results. Muscle Nerve, 2015 Muscle Nerve 54: 18-24, 2016 Muscle Nerve 54: 18-24, 2016.

Bochum ultrasound score versus clinical and electrophysiological parameters in distinguishing acute-onset chronic from acute inflammatory demyelinating polyneuropathy.

INTRODUCTION: The aim of this study was to evaluate whether a nerve ultrasound score (Bochum ultrasound score, BUS), clinical, and electrophysiological parameters could distinguish subacute chronic (CIDP) from acute inflammatory demyelinating polyneuropathy (AIDP). METHODS: Phase 1: The charts of 35 patients with polyradiculoneuropathy were evaluated retrospectively regarding BUS, clinical, and electrophysiological parameters (A-waves, sural nerve sparing pattern, sensory ratio>1). Phase 2: All parameters were evaluated prospectively in 10 patients with subacute polyradiculoneuropathy. RESULTS: Phase 1: A sum score of ≥2 points in BUS and the presence of sensory symptoms were significantly more frequent in the subacute CIDP group than in the AIDP group (P<0.001).The electrophysiological parameters showed no significant changes between the 2 groups. Phase 2: BUS (83.3%; 100%;), sensory symptoms (100%; 75%), absence of autonomic nervous system dysfunction (83.3%; 75%), or bulbar palsy (83.3%; 50%) showed the best sensitivity and specificity in distinguishing subacute CIDP from AIDP. CONCLUSIONS: BUS is a useful diagnostic tool for distinguishing subacute CIDP from AIDP.

Multifocal motor neuropathy: correlation of nerve ultrasound, electrophysiological, and clinical findings.

We present nerve ultrasound findings in multifocal motor neuropathy (MMN) and examine their correlation with electrophysiology and functional disability. Eighty healthy controls and 12 MMN patients underwent clinical, sonographic, and electrophysiological evaluation a mean of 3.5 years (standard deviation [SD] ± 2.1) after disease onset. Nerve ultrasound revealed significantly higher cross-sectional area (CSA) values of the median (forearm, p < 0.001), ulnar (p < 0.001), and tibial nerve (ankle, p < 0.001) when compared with controls. Electroneurography documented signs of significantly lower values of the motor conduction velocity and compound muscle action potentials (cMAPs) in the upper arm nerves (median, ulnar, radial, p < 0.001). A significant correlation between sonographic and electrophysiological findings in the MMN group was found only between cMAP and CSA of the median nerve at the upper arm (r = 0.851, p < 0.001). Neither nerve sonography nor electrophysiology correlated with functional disability. MMN seems to show inhomogeneous CSA enlargement in various peripheral nerves, with weak correlation to electrophysiological findings. Neither nerve sonography nor electrophysiology correlated with functional disability. Multicentre, prospective studies are required to prove the applicability and diagnostic values of these findings.

Nerve sonography in the diagnostic evaluation of primary and secondary carpal tunnel syndrome in rheumatoid arthritis.

BACKGROUND AND PURPOSE: Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy and extra-articular manifestation of rheumatoid arthritis (RA). However, in patients with RA, it is not always possible to clinically distinguish an actual CTS from other RA-based complaints. METHODS: We evaluated the diagnostic role of nerve ultrasound (NUS) as supportive tool in the diagnostic process of CTS in patients with RA and tried to provide etiological clarification in cases of secondary CTS. Fifty-eight patients with RA and clinical suspicion of CTS were enrolled. All patients underwent a standardized clinical-neurological, electrophysiological (nerve conduction studies [NCS]), and NUS examination and completed the Boston CTS Questionnaire (BCTQ). RESULTS: In 96 of 116 hands examined, a clinical suspicion of CTS was documented. In 43 of 96 (44.8%) CTS-positive hands, the diagnosis was primarily confirmed by NCS, whereas in another 16 of 96 (30.2%) hands, the diagnosis could only be verified by NUS, leading to a diagnosis of CTS in 59 of 116 (50.8%) hands. In 19 of 59 (32.3%) CTS-positive hands, tenosynovial hypertrophy was observed, and in 7 of 59 (11.8%), a cystic mass was identified as the underlying cause of secondary CTS. A good correlation between NCS and NUS findings was documented, but no significant correlation was found between NCS, NUS, and clinical findings/BCTQ. CONCLUSIONS: In people with RA, a diagnosis of CTS purely on a clinical basis is nonspecific and should be supported by NCS and/or NUS. NUS markedly facilitates the diagnosis of CTS in these patients and enables differentiation between primary and secondary causes.

Nerve ultrasound in a case of chronic inflammatory demyelinating neuropathy.

INTRODUCTION: Chronic inflammatory demyelinating polyneuropathy (CIDP) is the most common acquired immune-mediated inflammatory disorder of the peripheral nervous system. The diagnosis is based mainly on the clinical presentation and electrophysiological detection of demyelination. METHODS: Several MRI studies have demonstrated hypertrophy and abnormal enhancement of spinal nerve roots or brachial plexus in CIDP, but there have been only anecdotal reports of similar sonographic findings. RESULTS: This article reports the sonographic findings of a CIDP case and includes a review of the literature and previously reported cases. CONCLUSIONS: This case report highlights the importance of sonography in the localization and recognition of focal nerve enlargements in patients with CIDP. This method could be a helpful tool in the diagnosis of conduction block in CIDP, especially in cases where a nerve segment cannot be explored easily with the inching technique. Systematic data are needed to confirm this observation.

Correlation of nerve ultrasound, electrophysiological, and clinical findings in post Guillain-Barré syndrome.

We aimed to correlate functional disability, electrophysiology, and nerve ultrasound in patients after Guillain-Barré syndrome (GBS). Seventy-five healthy controls and 41 post-GBS patients (mean 3.4 years, SD ± 2.91 years after onset) underwent clinical, sonographic, and electrophysiological evaluation. Compared to healthy controls, the post-GBS patients showed: (1) a mean Rasch-built Overall Disability Scale score of 31.8 (SD ± 11.6), modified Rasch-built fatigue severity scale score of 15.6 (SD ± 3.2), Medical Research Council sum score of 22 (SD ± 5.6); (2) electrophysiological signs of permanent axonal loss in the majority of the peripheral nerves; (3) sonographical evidence of higher cross-sectional area values (CSA) of the ulnar (elbow, p < 0.001), radial (spiral groove, p < 0.001), tibial nerve (popliteal fossa, p < 0.001) and brachial plexus (supraclavicular space, p < 0.001). No correlation between sonographic and electrophysiological findings was found. Neither nerve ultrasound nor electrophysiology correlated with muscle strength, overall disability, and fatigue scale. Compared to healthy controls, post-GBS patients had significant functional disability. Despite significant abnormalities in both electrophysiology and ultrasound compared to healthy controls, neither electrophysiology nor nerve ultrasound correlated with functional disability of these patients.

Clopidogrel load for emboli reduction in patients with symptomatic carotid stenosis undergoing urgent carotid endarterectomy.

BACKGROUND AND PURPOSE: Microembolic signals (MES) on transcranial Doppler are an independent risk factor for recurrent stroke in patients with extracranial symptomatic/asymptomatic carotid artery stenosis (CARAS). Clopidogrel load (300 mg) combined with dual antiplatelet therapy has been shown to reduce MES in patients with symptomatic CARAS. We sought to determine feasibility of clopidogrel load in decreasing asymptomatic embolization in patients with symptomatic CARAS undergoing urgent carotid endarterectomy within the first 2 weeks from the index event. Subjects and METHODS: Consecutive patients with symptomatic CARAS (70%-99%) and presence of MES on 1-hour baseline (<24 hours from the index event) transcranial Doppler monitoring of ipsilateral middle cerebral artery were treated with clopidogrel load followed by clopidogrel (75 mg)±aspirin (100 mg) during the elapsed time period between hospital admission and urgent carotid endarterectomy at 3 tertiary-care stroke centers. Repeat 1-hour transcranial Doppler monitoring was performed the day before surgery. Bleeding complications during surgery and recurrent strokes or transient ischemic attacks during the first month of ictus were prospectively recorded. RESULTS: A total of 11 symptomatic CARAS patients (mean age, 66±7 years; 73% men; 64% acute ischemic strokes) were treated with clopidogrel load followed by dual (67%) or single (33%) antiplatelet therapy. MES count was significantly reduced between baseline (median count, 8 MES/h; interquartile range, 6-19) and repeat transcranial Doppler monitoring (0 MES/h; interquartile range, 0-3; P=0.003). No bleeding complications, recurrent strokes, or transient ischemic attacks were documented. CONCLUSIONS: Our pilot observational study provides preliminary nonrandomized data regarding the potential efficacy of clopidogrel load to reduce asymptomatic embolization in patients with symptomatic CARAS before urgent carotid endarterectomy.

High-Resolution Nerve Ultrasound to Assess Nerve Echogenicity, Fascicular Count, and Cross-Sectional Area Using Semiautomated Analysis.

BACKGROUND AND PURPOSE: Little is known about echogenicity and fascicular structure observed in high-resolution nerve ultrasound (HRUS) in both healthy subjects and patients with peripheral nerve disease. The aim of this study was to evaluate the reliability of echogenicity, fascicle count, and fascicle size analysis, to create standard values and compare these parameters to patients with chronic inflammatory demyelinating polyneuropathy (CIDP). METHODS: Median, ulnar, radial, tibial, and fibular nerve of 79 healthy subjects and patients were scanned by one examiner using HRUS. Image analysis regarding echogenicity, fascicle count, and fascicle cross-sectional area (CSA) was performed by two independent raters semiautomatically using ImageJ. Pearson correlation coefficient r reflected interrater reliability (IR), and intraclass correlation coefficient (ICC) determined intrarater reliability (IAR). Results of healthy subjects were compared to 20 patients with CIDP by analysis of variance. RESULTS: IR was very good for echogenicity (r = .9) and good for fascicle count and size of the largest fascicle (r = .64/.56). IAR was very good for all three parameters (ICC = .9/.83/.74). Healthy subjects had a wide range of values. CIDP patients were in range of healthy subjects. Clinically progressive CIDP patients (defined as an increase in Overall Disability Sum Score by ≥1 point) had a lower fraction of black than healthy controls and stable CIDP patients (P < .001). CONCLUSION: Semiautomated evaluation of echogenicity, fascicle count, and fascicle CSA is reliable. Cutoff values to differentiate between healthy persons and CIDP do not exist. Echogenicity is useful for detecting clinically progressive CIDP patients and should be used in clinical context or intraindividual course.

Ultrasound, Clinical, and Electrophysiological Findings in Persistent Carpal Tunnel Syndrome.

BACKGROUND AND PURPOSE: We present the clinical, electrophysiological, and nerve ultrasound findings in cases of persistent carpal tunnel syndrome (PCTS). METHODS: Eighteen PCTS patients underwent evaluation with the Boston Carpal Tunnel Syndrome Questionnaire (BCTSQ), electrophysiology, and nerve ultrasound with a mean of 3.5 months (SD ± 1.4) after open surgery. RESULTS: PCTS patients showed a mean symptom severity scale score of 3.1 (SD ± 1.1) and functional severity scale score of 3.2 (SD ± 0.9) in BCTSQ. Nerve conduction studies revealed axonal affection of the median nerve in 13/18 patients, ultrasound showed disturbed echogenicity in all patients, a pathological wrist to forearm ratio in 16/18 patients, and cross-sectional area enlargement of the median nerve at the distal wrist crease in 12/18 patients. Ultrasound documented scar tissue formation (in 12/18 patients), incomplete release of retinaculum flexorum (in 4/18 patients), and neuroma of the median nerve (in 2/18 patients) as PCTS cause. CONCLUSION: Our data show significant functional disability, axonal nerve damage, and scar tissue formation as common PCTS causes.

Clinical, Sonographic, and Electrophysiologic Longitudinal Features of Chronic Inflammatory Demyelinating Polyneuropathy.

BACKGROUND AND PURPOSE: Several studies have aimed to find potential biomarkers to simplify the diagnosis of chronic inflammatory demyelinating polyneuropathy (CIDP) and to monitor and predict the disease course. However, reliable markers are still lacking. We aimed to investigate whether high-resolution nerve ultrasound (HRUS) is suitable for monitoring the long-term clinical course of CIDP. METHODS: Twenty patients fulfilling the definite diagnostic criteria of CIDP received clinical examination, evaluation of the INCAT (inflammatory neuropathy cause and treatment) overall disability sum score (ODSS) as well as nerve conduction studies, and HRUS every 6 months over a median follow-up time of 34 months. Patients were divided into clinically stable/regressive disease course or progressive disease course according to the development of the ODSS. RESULTS: The intranerve cross-sectional-area (CSA) variability of the nerves of the lower extremity increased with disease progression, whereas it remained unchanged in patients with a stable or remitting disease course. CONCLUSION: Nerve ultrasound can be used as a method to objectify the long-term disease course in CIDP patients. The intranerve CSA variability is suitable for monitoring the clinical course of patients with CIDP.

Nerve echogenicity and intranerve CSA variability in high-resolution nerve ultrasound (HRUS) in chronic inflammatory demyelinating polyneuropathy (CIDP).

OBJECTIVE: HRUS is increasingly being used in the diagnosis and evaluation of autoimmune neuropathies such as CIDP. Recently, studies focused not only on changes of nerves size, but also the fascicular structure and the echogenicity changes in CIDP. However, little is known about the alterations of echogenicity in the long-term course in CIDP. The aim of this study was to evaluate echogenicity in CIDP patients in a long-term follow-up period and to analyze the benefit of the evaluation of echogenicity compared to nerve size. METHODS: 20 patients fulfilling the definite diagnostic criteria of CIDP received clinical examination, nerve conduction studies and HRUS every 6 months over a median follow-up time of 34 months. Patients were divided into clinically stable/regressive disease course or progressive disease course according to the development of the inflammatory neuropathy cause and treatment overall disability sum score. Echogenicity of peripheral nerves was measured semi-automated and quantitative. Echogenicity was divided into three classes by fraction of black: hypoechogenic, mixed hypo-/hyperechogenic, hyperechogenic. RESULTS: Patients with hyperechogenic arm nerves more frequently show clinical worsening, whereas patients with hypoechogenic arm nerves remain stable or even improved over time. In the long-term course of the disease, echogenicity mostly did not change, and if changes occured echogenicity did not correspond to ODSS changes. CONCLUSION: Echogenicity of the arm nerves in CIDP may be used as a prognostic marker, but not as a follow-up tool for evaluating clinical changes. Further studies in a larger cohort are needed to confirm these results.