Quantitative sonographic evaluation of muscle thickness and fasciculation prevalence in healthy subjects

The value of ultrasound measurement of muscle thickness at different sites and shear wave elastography in Parkinson's disease with sarcopenia: a pilot study

Background

Patients with Parkinson's disease (PD) and sarcopenia often exhibit resilience, frailty, disability, and depression, highlighting the complex and interrelated nature of these conditions.

Objective

Despite the presence of clinical manifestations of muscle atrophy in both PD and sarcopenia, accurately discerning the coexistence of sarcopenia in PD patients remains a challenging task with significant implications for treatment strategies and prognostic assessments. This study aims to elucidate the specific ultrasonic diagnostic parameters associated with PD accompanied by sarcopenia through a comparative analysis of muscle ultrasound parameters in patients with PD, thereby presenting a novel approach for rapid identification of this condition.

Methods

A total of 110 participants were enrolled in this study, including patients with PD and control subjects. Demographic data, clinical characteristics, physical performance tests, appendicular skeletal muscle mass index (ASMI), bioelectrical impedance analysis and muscle ultrasound measurements were collected from all participants. The muscle ultrasound measurements encompassed assessments of muscle thickness, pennation angle and shear wave elastography at various anatomical sites.

Results

Parkinson's disease patients exhibited decreased muscle strength and physical performance, and increased shear wave elastography value. In PD patients with sarcopenia, body circumference, including calf circumference, mid-arm circumference, Waist-to-Hip Ratio and body mass index (BMI) were all significantly decreased. Biceps brachii muscle thickness (MT) and gastrocnemius MT decreased in PD patients with sarcopenia and low ASMI. Binary logistic regression analysis revealed that male PD patients, BMI and gastrocnemius MT were predictive factors for ASMI in PD patients.

Conclusion

Biceps brachii MT and gastrocnemius MT are important indicators for distinguishing whether PD patients have sarcopenia. Male patients, low BMI and gastrocnemius MT were identified as valid predictors of low ASMI in PD patients. The findings of this study provide important insights into the use of muscle ultrasound in the diagnosis of PD with sarcopenia.

Systematic Comparison of Muscle Ultrasound Thickness in Polyneuropathies and Other Neuromuscular Diseases

BACKGROUND

We have aimed to assess whether muscle thickness ultrasound (US) shows differences between patients with chronic inflammatory demyelinating polyneuropathy (CIDP), chronic axonal polyneuropathy (CAP), and other neuromuscular (NM) diseases compared to controls and to each other.

METHODS

We performed a cross-sectional study from September 2021 to June 2022. All subjects underwent quantitative sonographic evaluation of muscle thickness in eight relaxed muscles and four contracted muscles. Differences were assessed using multivariable linear regression, correcting for age and body mass index (BMI).

RESULTS

The study cohort consisted of 65 healthy controls, and 95 patients: 31 with CIDP, 34 with CAP, and 30 with other NM diseases. Both relaxed and contracted muscle thickness in all patient groups were lower than in the healthy controls, after controlling for age and body mass index (BMI). Regression confirmed that the differences persisted between patient groups and healthy controls. Differences between patient groups were not apparent.

CONCLUSION

The current study shows that muscle ultrasound thickness is not specific in NM disorders, but shows a global reduction in thickness compared with healthy controls after corrections for age and BMI.

Quantitative sonographic assessment of muscle thickness and fasciculations distribution is a sensitive tool for neuromuscular disorders

INTRODUCTION

Loss of muscle thickness can be demonstrated in a wide spectrum of neuromuscular disorders, while fasciculations are more frequent in amyotrophic lateral sclerosis (ALS). In the current study, we aimed to determine the sensitivity and specificity of quantitative sonographic assessment of muscle thickness and the presence of fasciculations for diagnosing various neuromuscular disorders.

METHODS

The thickness and the presence of fasciculations in eight muscles were determined by sonography in patients with myopathy (22), polyneuropathy (36), ALS (91), and spinal muscular atrophy (SMA) (31) and compared to normative values determined in 65 heathy control subjects.

RESULTS

Reduced muscle thickness in at least one relaxed muscle showed 92-100% sensitivity for diagnosing a neuromuscular disease, with a specificity of 85% for differentiating patients from heathy controls (AUC = 0.90). Subtracting distal from proximal muscle thickness may differentiate between myopathy and polyneuropathy. Fasciculations in ≥1 proximal muscle showed good diagnostic accuracy (AUC = 0.87) for diagnosing ALS.

DISCUSSION

Sonographic assessment of muscle thickness is a sensitive tool for diagnosing a wide spectrum of neuromuscular diseases, and may facilitate diagnosis even in patients with normal strength on neurological examination, while the presence of fasciculations in proximal muscles may facilitate ALS diagnosis.

The Sensitivity of Quantitative Sonographic Assessment of Muscle Thickness for Amyotrophic Lateral Sclerosis Diagnosis

PURPOSE

In the current proof-of-concept study, we aimed to examine the sensitivities and specificities of previously reported normal values for muscle ultrasound thickness in amyotrophic lateral sclerosis.

METHODS

Muscle ultrasound was performed in 65 healthy control subjects and 91 amyotrophic lateral sclerosis patients using a standardized assessment of eight relaxed muscles and four contracted muscles. Normal values for muscle thickness were determined as values above the 5th percentile stratified by age and gender using the weighted average method. Sensitivity for amyotrophic lateral sclerosis diagnosis was determined for muscles with and without the addition of muscle contraction.

RESULTS

Amyotrophic lateral sclerosis patients showed reduced muscle sum thickness both in relaxed and in contracted states compared with control subjects. Muscle ultrasound of muscles with and without contraction showed excellent diagnostic accuracy for differentiating amyotrophic lateral sclerosis patients from control subjects (area under curve = 0.96, sensitivity: 93%-95%, specificity: 84-87). Muscle ultrasound sensitivity was lower within 6 months of symptom onset (83%) compared with longer disease duration (>92%).

CONCLUSIONS

Quantitative sonographic assessment of muscle thickness can be complementary in the diagnosis of amyotrophic lateral sclerosis with excellent accuracy for differentiating patients from healthy subjects, and might be useful in other neuromuscular disorders, although additional studies are required.

Current evidence regarding 2D ultrasonography monitoring of intrinsic foot muscle properties: A systematic review

Background

Ultrasonography can discriminate between intrinsic and extrinsic foot muscle properties and has therefore gained considerable popularity as an indirect strength evaluation. However, an overview on the use of ultrasound for assessing intrinsic foot musculature (IFM) is currently lacking.

Research question

What is the current evidence regarding (1) 2D ultrasonography protocols and its reliability? (2) Reference values for cross-sectional area and dorso-plantar thickness evaluation in asymptomatic and symptomatic persons?

Methods

The PRISMA guidelines were used to conduct this systematic review. Eight databases (PubMed, Embase, Web of Science, Cochrane Library, Scopus, CINAHL, SPORTDiscus and EuropePMC) were searched up to November 1, 2021. Studies reporting quantitative 2D ultrasound findings of the intrinsic foot muscles with no limitation to sex, BMI, ethnicity or physical activity were included. Studies were assessed for methodological quality using the Downs and Black checklist.

Results

Fifty-three studies were retained. Protocols showed an overall good to great reliability, suggesting limits of agreement between 8 and 30% of relative muscle size with minimal detectable changes varying from 0.10 to 0.29 cm² for cross-sectional area and 0.03-0.23 cm for thickness. Reference values are proposed for both cross-sectional area and thickness measurements of the abductor hallucis, flexor digitorum brevis, flexor hallucis brevis and quadratus plantae in asymptomatic persons. This could not be performed in the symptomatic studies due to a limited number of relevant studies addressing the symptomatic population, therefore a clinical overview is outlined. Clinically, IFM properties have been studied in ten distinct pathological conditions, predominantly pointing towards decreased muscle properties of the abductor hallucis.

Significance

We provide a clear and comprehensive overview of the literature regarding 2D ultrasonography of the IFM, making the available evidence more accessible to decision makers and researchers.

The Sensitivity and Specificity of Split-Hand Index Using Muscle Sonography

BACKGROUND

The split-hand index (SHI) (first dorsal interosseous (FDI) × abductor pollicis brevis (APB)/abductor digiti minimi muscle (ADM)) has been suggested as a useful measure for amyotrophic lateral sclerosis (ALS) diagnosis, using electrophysiological and sonographic indices. In the present study, we aimed to explore the specificity of SHI derived by muscle ultrasound (MUS) for the diagnosis of ALS and spinal muscular atrophy (SMA).

METHODS

Healthy controls (n = 65) were prospectively recruited at the Prosserman Family Neuromuscular clinic at Toronto General Hospital, from October to December 2018. In addition, 181 patients with ALS (n = 91), SMA (n = 33), polyneuropathy (n = 35), and myopathy (n = 22) were prospectively recruited at the neuromuscular clinic at Tel Aviv Sourasky Medical Center, from December 2018 to December 2020. All subjects underwent quantitative sonographic evaluation of muscle thickness, including the right APB, FDI, and ADM muscles. Area under curve (AUC), sensitivity, and specificity were determined for differentiating between groups.

RESULTS

Although SHI showed good to excellent accuracy for differentiating each patient subgroup from controls (AUC 0.83-0.92), poorer diagnostic accuracy was shown for differentiating between different patient subgroups (AUC 0.54-0.74).

CONCLUSIONS

Sonographic SHI is useful for differentiating patients from healthy controls, but might be not specific for motor neuron disease.

Fasciculation intensity and limb dominance in amyotrophic lateral sclerosis: a muscle ultrasonographic study

Background and purpose

Muscle ultrasonography has been increasingly recognized as a useful tool for detection of fasciculations. Separately, concordance between dominant hand and onset side has been reported in amyotrophic lateral sclerosis (ALS). The aim of this study was to reveal the distribution of fasciculations in the whole body, focusing on handedness.

Methods

In 106 consecutive patients with ALS, muscle ultrasonography was systematically performed in 11 muscles (the tongue, and bilateral biceps brachii, 1st dorsal interosseous [FDI], T10-paraspinalis, vastus lateralis and tibialis anterior muscles). The fasciculation intensity was scored from 0 to 3 for each muscle.

Results

Fasciculations were more frequently found in the limb muscles than the tongue and paraspinalis. Side and handedness analyses revealed that fasciculation intensity in FDI was significantly more prominent on the right (median [inter-quartile range] 2 [0 - 3]) than left (1.5 [0 - 3]; p = 0.016), and in the dominant hand (2 [1 - 3]) than non-dominant side (1.5 [0 - 3]; p = 0.025). The differences were greater in patients with upper limb onset. There were no side differences in the lower limb muscles. Multivariate analyses showed that male patients had more frequent fasciculations in the dominant FDI (β = 0.22, p < 0.05).

Conclusion

More intensive fasciculations are present in the FDI in the dominant hand and gender might be associated with fasciculation intensities. This distribution pattern of fasciculations might be associated with pathogenesis of ALS.

Quantitative ultrasound imaging of intrinsic hand muscles after traumatic cervical spinal cord injury

STUDY DESIGN

This is a cross-sectional descriptive study.

OBJECTIVES

To quantify differences in hand muscle morphology between persons with cervical spinal cord injury (SCI) and uninjured adults.

SETTING

The study was performed at the Guangdong Work Injury Rehabilitation Hospital.

METHODS

We quantified hand muscle cross-sectional area (CSA), thickness, and echo intensity (EI) in 18 persons with subacute to chronic SCI and 23 controls using ultrasound imaging.

RESULTS

Mean SCI abductor pollicis brevis (APB), abductor digiti minimi (ADM), and first dorsal interosseous (FDI) CSA were ~26%, 43%, and 37% smaller than the control means, the deficit in the APB being less than the ADM (P < 0.05). Muscle thickness was also smaller after SCI, but deficits in ADM (31%) and FDI (20%) thickness were less than the CSA deficits (P < 0.05). In five SCI persons, APB CSA and/or opponens pollicis (OP) thickness were normal despite complete motor paralysis. Mean longitudinal image EI was 40% higher in the OP and 15% higher in the flexor pollicis brevis (FPB) after SCI (P < 0.05), suggesting denervation-induced infiltration of fat and fibrous tissues. OP EI was related to OP thickness (r = -0.6, P = 0.007, n = 18). Mean axial image EI was 10% higher in the APB and ADM after SCI (P < 0.05). There were no significant correlations between muscle morphological properties and clinical features in the SCI participants.

CONCLUSION

Our results indicate significant SCI atrophy and elevated EI that are muscle dependent.

Muscle ultrasound: Present state and future opportunities

Muscle ultrasound is a valuable addition to the neuromuscular toolkit in both the clinic and research settings, with proven value and reliability. However, it is currently not fulfilling its full potential in the diagnostic care of patients with neuromuscular disease. This review highlights the possibilities and pitfalls of muscle ultrasound as a diagnostic tool and biomarker, and discusses challenges to its widespread implementation. We expect that limitations in visual image interpretation, posed by user inexperience, could be overcome with simpler scoring systems and the help of deep-learning algorithms. In addition, more information should be collected on the relation between specific neuromuscular disorders, disease stages, and expected ultrasound abnormalities, as this will enhance specificity of the technique and enable the use of muscle ultrasound as a biomarker. Quantified muscle ultrasound gives the most sensitive results but is hampered by the need for device-specific reference values. Efforts in creating dedicated muscle ultrasound systems and artificial intelligence to help with image interpretation are expected to improve usability. Finally, the standard inclusion of muscle and nerve ultrasound in neuromuscular teaching curricula and guidelines will facilitate further implementation in practice. Our hope is that this review will help in unleashing muscle ultrasound's full potential.

Fasciculation frequency at the biceps brachii and brachialis muscles is associated with amyotrophic lateral sclerosis disease burden and activity

INTRODUCTION

Fasciculations are most commonly seen in the biceps brachii muscle in amyotrophic lateral sclerosis (ALS). In this study we have explored the association between fasciculation frequency in a single location-biceps brachii and brachialis muscles (BB), and disease burden and activity.

METHODS

Sonographic muscle studies were performed in 90 ALS patients, 47 of whom were seen in subsequent follow-up. The association between fasciculations frequency at the BB and ALS Functional Rating Scale-Revised (ALSFRS-R) and manual muscle testing (MMT) scores was determined.

RESULTS

High fasciculation frequency at the BB, where detection rate was the highest, was associated with shorter disease duration, greater muscle thickness, higher MMT scores, and faster rate of decline in ALSFRS-R initially, and MMT subsequently.

DISCUSSION

High fasciculation frequency at the BB as determined by sonography, is associated with less impairment at time of examination, and a more active disease with a more rapid progression.

Ultrasound Measurement of Skeletal Muscle Contractile Parameters Using Flexible and Wearable Single-Element Ultrasonic Sensor

Skeletal muscle is considered as a near-constant volume system, and the contractions of the muscle are related to the changes in tissue thickness. Assessment of the skeletal muscle contractile parameters such as maximum contraction thickness (Th), contraction time (Tc), contraction velocity (Vc), sustain time (Ts), and half-relaxation (Tr) provides valuable information for various medical applications. This paper presents a single-element wearable ultrasonic sensor (WUS) and a method to measure the skeletal muscle contractile parameters in A-mode ultrasonic data acquisition. The developed WUS was made of double-layer polyvinylidene fluoride (PVDF) piezoelectric polymer films with a simple and low-cost fabrication process. A flexible, lightweight, thin, and small size WUS would provide a secure attachment to the skin surface without affecting the muscle contraction dynamics of interest. The developed WUS was employed to monitor the contractions of gastrocnemius (GC) muscle of a human subject. The GC muscle contractions were evoked by the electrical muscle stimulation (EMS) at varying EMS frequencies from 2 Hz up to 30 Hz. The tissue thickness changes due to the muscle contractions were measured by utilizing a time-of-flight method in the ultrasonic through-transmission mode. The developed WUS demonstrated the capability to monitor the tissue thickness changes during the unfused and fused tetanic contractions. The tetanic progression level was quantitatively assessed using the parameter of the fusion index (FI) obtained. In addition, the contractile parameters (Th, Tc, Vc, Ts, and Tr) were successfully extracted from the measured tissue thickness changes. In addition, the unfused and fused tetanus frequencies were estimated from the obtained FI-EMS frequency curve. The WUS and ultrasonic method proposed in this study could be a valuable tool for inexpensive, non-invasive, and continuous monitoring of the skeletal muscle contractile properties.

Split-hand phenomenon in motor neuron diseases: Sonographic assesment of muscle thickness

OBJECTIVE

To explore the diagnostic accuracy of the split-hand index (SHI) for amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA) using sonographic assessment of muscle thickness.

METHODS

We performed a prospective sonographic assessment of hand muscle thickness in 59 controls, 87 patients with ALS, and 33 patients with SMA. We determined the diagnostic accuracy of SHI for differentiating patients with ALS and SMA from controls.

RESULTS

Patients with ALS and SMA had significantly lower muscle thickness and SHI values compared with controls. SHI showed excellent diagnostic accuracy for differentiating ALS from controls, and good diagnostic accuracy for differentiating SMA from controls.

CONCLUSIONS

SHI determined by sonographic measurement of hand muscle thickness seems to be a promising tool for the diagnosis of ALS and may be added easily when performing neuromuscular ultrasound.

SIGNIFICANCE

SHI determined by sonographic measurement of hand muscle thickness can differentiate between healthy subjects and patients with ALS and SMA.