A driven academic who loves teaching and research. Skilled in training ultrasound to novice and advanced practitioners. Always looking for collaborations to establish and new horizons to explore.
In recent years, imaging has played an increasing role in the clinical management of patients wit... more In recent years, imaging has played an increasing role in the clinical management of patients with rheumatic diseases with respect to aiding diagnosis, guiding therapy and monitoring disease progression. These roles have been underpinned by research which has enhanced our understanding of disease pathogenesis and pathophysiology of rheumatology conditions, in addition to their key role in outcome measurement in clinical trials. However, compared to joints, imaging research of muscles is less established, despite the fact that muscle symptoms are very common and debilitating in many rheumatic diseases. Recently, it has been shown that even though patients with rheumatoid arthritis may achieve clinical remission, defined by asymptomatic joints, many remain affected by lingering constitutional systemic symptoms like fatigue, tiredness, weakness and myalgia, which may be attributed to changes in the muscles. Recent improvements in imaging technology, coupled with an increasing clinical interest, has started to ignite new interest in the area. This perspective discusses the rationale for using imaging, particularly ultrasound and MRI, for investigating muscle pathology involved in common inflammatory rheumatic diseases. The muscles associated with rheumatic diseases can be affected in many ways, including myositis-an inflammatory muscle condition, and myopathy secondary to medications, such as glucocorticoids. In addition to non-invasive visual assessment of muscles in these conditions, novel imaging techniques like shear wave elastography and quantitative MRI can provide further useful information regarding the physiological and biomechanical status of the muscle.
Purpose:
To investigate the reproducibility of shear wave elastography (SWE) among operators, mac... more Purpose: To investigate the reproducibility of shear wave elastography (SWE) among operators, machines and probes in a phantom. Moreover, to evaluate the effect of depth and the accuracy of the embedded inclusions. Methods: In-vitro stiffness measurements of six inclusions (10kPa, 40kPa and 60kPa) embedded at two depths (1.5cm and 5cm) in an elastography phantom. The measurements obtained by two sonographers using two ultrasound machines; the SuperSonic Imagine Aixplorer using the XC6-1, SL10-2 and SL18-5 probes, and the General Electric LOGIQ E9 using the 9L-D probe. The variability was evaluated using the coefficient of variation. The reproducibility was calculated using an intraclass correlation coefficient (ICC). Results: For shallow inclusions, low variability was observed between the results obtained by each operator (range 0.9%–5.4%). However, the variability increased significantly in the deeper inclusions (range 2.4–80.8%). The measurement difference between the operators was 1%–15% in superficial inclusions and 3%–43% in deep inclusions. The inter-operator reproducibility was almost perfect (ICC>0.90). The measurement difference between the machines was 0–15% in superficial inclusions and 38.6%–82.9% in deep inclusions. In superficial inclusions, there was an excellent reproducibility between the three probes (ICC>0.97). On average, the means of the 10 kPa inclusions’ stiffness were overestimated by 16%, while those at 40 kPa and 60 kPa were underestimated by 42% and 48%, respectively. Conclusion: Phantom SWE measurements were reproducible between operators, machines and probes at superficial depths only. SWE measurements acquired in deep regions should not be used interchangeably between operators, machines or probes.
Objective
To determine inter- and intra-reader reproducibility of shear wave elastography measure... more Objective To determine inter- and intra-reader reproducibility of shear wave elastography measurements for musculoskeletal soft tissue masses.
Materials and methods In all, 64 patients with musculoskeletal soft tissue masses were scanned by two readers prior to biopsy; each taking five measurements of shear wave velocity (m/s) and stiffness (kPa). A single lesion per patient was scanned in transverse and cranio-caudal planes. Depth measurements (cm) and volume (cm3) were recorded for each lesion, for each reader. Linear mixed modelling was performed to assess limits of agreement (LOA), inter- and intra-reader repeatability, including analyses for measured depth and volume.
Results Of the 64 lesions scanned, 24 (38%) were malignant. Bland-Altman plots demonstrated negligible bias with wide LOA for all measurements. Transverse velocity was the most reliable measure—intraclass correlation (95% CI) = 0.917 (0.886, 1)—though reader 1 measures could be between 38% lower and 57% higher than reader 2 [ratio-scale bias (95% LOA) = 0.99 (0.64, 1.55)]. Repeatability coefficients indicated most disagreement resulted from poor within-reader reproducibility. LOA between readers calculated from means of five repeated measurements were narrower—transverse velocity ratio-scale bias (95% LOA) = 1.00 (0.74, 1.35). Depth affected both estimated velocity and repeatability; volume also affected repeatability.
Conclusion This study found poor repeatability of measurements with wide LOA due mostly to intra-reader variability. Transverse velocity was the most reliable measure; variability may be affected by lesion depth. At least five measurements should be reported with LOA to assist future comparability between shear wave elastography systems in evaluating soft tissue masses.
International Journal of Rheumatic Dsiseases, 2019
Aim
To investigate muscle stiffness changes in patients treated for giant cell arteritis (GCA) wi... more Aim To investigate muscle stiffness changes in patients treated for giant cell arteritis (GCA) with high‐dose oral glucocorticoids.
Methods Using ultrasound elastography, shear wave velocity (SWV) was measured in the quadriceps, hamstrings and biceps brachii muscles of 14 patients with GCA (4 male, mean age ± SD, 68.2 ± 4.3 years) within the first 2 weeks of initiating glucocorticoid treatment (baseline) and repeated after 3 and 6 months treatment. Muscle strength and performance tests were performed at each visit. Baseline measures were compared with those from 14 healthy controls. Linear mixed models were used to test for change in patient measures over time.
Results At baseline, muscle SWV in patients was not significantly different from controls. With glucocorticoid treatment, there was a reduction in SWV in the leg but not the arm muscles. SWV decreased by a mean of 14% (range 8.3%‐17.3%; P = .001) after 3 months and 18% (range 10.2%‐25.3%; P < .001) after 6‐months in the quadriceps and hamstrings during the resting position. The baseline, 3 and 6 months mean SWV (±SD) for the vastus lateralis were 1.62 ± 0.16 m/s, 1.40 ± 0.10 m/s and 1.31 ± 0.06 m/s, respectively (P < .001). In the patient group as a whole, there was no significant change in muscle strength. However, there were moderate correlations (r = .54‐.69) between exhibiting weaker muscle strength at follow‐up visits and a greater reduction in SWV.
Conclusion Glucocorticoid therapy in patients with GCA was associated with a significant reduction in proximal leg muscle stiffness during the first 6 months. Future research should study a larger sample of patients for a longer duration to investigate if diminished muscle stiffness precedes signs of glucocorticoid‐induced myopathy.
Objective:
To investigate muscle stiffness and strength in rheumatoid arthritis patients compare... more Objective: To investigate muscle stiffness and strength in rheumatoid arthritis patients compared to healthy controls.
Methods: A sample of 80 RA patients from three discrete groups: 1-newly diagnosed treatment-naïve RA (n = 29), 2-active RA for at least 1 year (n = 18) and 3-in remission RA for at least 1 year (n = 33), was compared to 40 healthy controls. Shear wave velocity (SWV) was measured using shear wave elastography as a surrogate for tissue stiffness in multiple muscles. All participants performed isometric grip strength, timed get-up-and-go test, 30-sec chair stand test and isokinetic knee extension/flexion(60°/sec). The difference in SWV amongst the groups was tested using one-way ANOVA, and the correlation between SWV and muscle strength results were calculated using Pearson’s coefficients.
Results: The mean age ± SD was 61.2 ± 12.8 for RA patients and 61.5 ± 10.5 years for controls. SWV was not significantly different amongst the groups on all muscles (p > 0.05). In comparison to controls, the new and active RA groups showed a significantly lower isokinetic strength by -29%(p = 0.013) and -28%(p = 0.040), fewer chair stands by -28%(p = 0.001) and -44%(p < 0.001), longer walking times by -25% (p = 0.025) and -30% (p = 0.001) respectively, and weaker grip strength by -45% for both (p < 0.001). The muscle strength in the remission RA groups was not significantly lower, except in the isokinetic knee strength (-21%; p = 0.027). The correlations between SWE and the muscle assessment results were weak and insignificant (r < 0.30; p > 0.05).
Conclusions: Significant muscle weakness was demonstrated in patients with RA disease. However, muscle stiffness was normal and not associated with muscle strength.
Objective
To investigate muscle stiffness in patients with idiopathic inflammatory myopathies (II... more Objective To investigate muscle stiffness in patients with idiopathic inflammatory myopathies (IIM) using shear wave elastography (SWE) and to correlate the results with muscle strength and MRI features of myositis.
Materials and methods Muscle shear wave velocity (SWV) was measured in 23 active IIM patients (13 females, mean age 50.4 ± 16.1 years) and 23 matched healthy controls (13 females, mean age 50.7 ± 16.2 years). The investigated muscles included the vastus lateralis (VL), rectus femoris (RF), vastus medialis (VM) vastus intermedius (VI), biceps femoris (BF), semitendinosus (ST), semimembranosus (SM) and the biceps brachii (BB) scanned during relaxed resting and passive stretching positions. Participants performed multiple tests to evaluate their muscle strength. IIM patients had a thigh MRI to assess degrees of oedema, fatty infiltration and atrophy.
Results In the resting position, IIM patients had a 12.9–22.2% significantly lower SWV (p < 0.05) for the quadriceps and hamstrings, but not BB. There was no difference during passive stretching. The SWV for VL, VI and BF showed moderate correlations with the muscle strength tests ranging from r = 0.47 to r = 0.70 (all p < 0.05). Lower SWV was associated with greater MRI scores of oedema (p = 0.001) and atrophy (p = 0.006). However, SWV did not correlate with fatty infiltration (r < 0.3; p = 0.28), creatine kinase (r = 0.28; p = 0.19) or disease duration (r = 0.26; p = 0.24).
Conclusion Shear wave elastography may detect abnormal reduced thigh stiffness in IIM patients. SWE measurements were significantly associated with muscle weakness and MRI signs of oedema and atrophy. Future research should investigate this new technology for monitoring disease activity.
Background:
Skeletal muscle undergoes structural changes with ageing which may alter its biomecha... more Background: Skeletal muscle undergoes structural changes with ageing which may alter its biomechanical properties. Shear wave elastography (SWE) may detect these changes by measuring muscle stiffness.
Aims: To investigate muscle stiffness in healthy young, middle-aged and elderly cohorts using SWE and correlate it with muscle strength and mass.
Methods: Shear wave velocity (SWV) was measured in the quadriceps, hamstrings and biceps brachii of 26 young (range 20–35 years), 21 middle-aged (40–55) and 30 elderly (77–94) volunteers. The participants performed several muscle tests to evaluate their strength. The One-way ANOVA was used to test the muscle stiffness differences between the groups and the Pearson’s correlation coefficient to evaluate the relationship between SWV and muscle strength.
Results: The overall resting muscle SWV gradually decreased with age but was only significantly reduced in the elderly group (p < 0.001); with the exception of the vastus lateralis SWV where a significant difference was noted (p < 0.05) between young (1.77 m/s), middle-aged (1.64 m/s) and elderly (1.48 m/s). The elderly group had on average 16.5% lower muscle stiffness compared to the young. SWV significantly correlated with muscle mass (r = 0.316), walking time (r = − 0.560), number of chair stands (r = 0.522), handgrip strength (r = 0.436) and isokinetic knee strength (r = 0.640). Sex and BMI did not explain any significant variation in SWV.
Conclusions: Ageing was associated with a decline in skeletal muscle stiffness which positively correlates with muscle weakness. Further research is needed to evaluate the promising role of SWE as a biomarker for sarcopenia assessment and potential falls risk prediction in elderly individuals.
Purpose:
To examine if shear-wave elastography (SWE) improves the accuracy of diagnosing soft-ti... more Purpose: To examine if shear-wave elastography (SWE) improves the accuracy of diagnosing soft-tissue masses as benign or malignant compared with US alone or in combination with MRI.
Materials and Methods: Two hundred six consecutive adult participants (mean age, 57.7 years; range, 18–91 years), including 89 men (median age, 56.0 years; range, 21–91 years) and 117 women (median age, 59.1 years; range, 18–88 years), who were referred for biopsy of a soft-tissue mass were prospectively recruited from December 2015 through March 2017. Participants underwent B-mode US, MRI, and SWE prior to biopsy. Three musculoskeletal radiologists independently reviewed US images alone, followed by US and MRI images together, and classified lesions as benign, probably benign, probably malignant, or malignant. For SWE, the area under the receiver operating characteristic (ROC) curve (AUC) was calculated for transverse shear-wave velocity (SWV). Multivariable logistic regression was used to investigate the association between SWE and malignancy alongside individual demographic and imaging variables.
Results: At histologic examination, 79 of 206 (38%) participants had malignant lesions. SWV showed good diagnostic accuracy for lesions classified as benign or probably benign by US alone (AUC = 0.87 [95% confidence interval {CI}: 0.79, 0.95]). SWV did not provide substantive diagnostic information for lesions classified as probably malignant or malignant, whether the classification was made with or without MRI. However, multivariable modeling indicated that diagnostic accuracy may vary by lesion position (interaction P = .02; superficial, odds ratio [OR] = 17.7 [95% CI: 1.50, 207], P = .02; deep/mixed, OR = 0.24 [95% CI: 0.07, 0.86], P = .03) and participant age (interaction P = .01; eg, age 43 years, OR = 0.72 [95% CI: 0.15, 3.5], P = .69; age 72 years, OR = 0.08 [95% CI: 0.02, 0.37], P = .001).
Conclusion: Shear-wave elastography can increase accuracy of soft-tissue lesion diagnosis in conjunction with US. However, a single cut-off may not be universally applicable with diagnostic accuracy that is affected by lesion position and patient age.
Purpose:
There is currently no standardized method for muscle shear wave elastography (SWE). The... more Purpose: There is currently no standardized method for muscle shear wave elastography (SWE). The objective of this study was to investigate the effect of unit of measurement, depth, and probe load on the reliability of muscle SWE.
Methods: The vastus lateralis, biceps femoris, biceps brachii, and abductor digiti minimi muscles were scanned on 20 healthy participants. The SWE readings were measured in shear wave velocity (m/s) and Young’s modulus (kPa). Three acquisitions of varying depths were acquired from vastus lateralis. Minimal probe load was compared with the use of a standoff gel layer. Three repeated measurements were acquired to assess reliability using intraclass correlations (ICC).
Results: The mean elasticity varied across muscle groups and ranged from 1.54 m/s for biceps femoris to 2.55 m/s for abductor digiti minimi (difference51.01 m/s [95% confidence interval, CI 0.92, 1.10]). Reporting readings in meters per second resulted in higher ICC of 0.83 (0.65, 0.93) in comparison to 0.77 (0.52, 0.90) for kilopascal for the vastus lateralis muscle only. Variance increased proportionally with depth reaching 0.17 (equivalent to 60.82 m/s) at 6 cm. Using a standoff gel decreased ICC to 0.63 (0.20, 0.84) despite similar mean elasticity readings to minimal probe load.
Conclusions: Different acquisition and technical factors may significantly affect the reliability of SWE in skeletal muscles. Readings acquired in the unit of shear wave velocity (m/s) from depths less than 4 cm using a minimal probe load without a standoff gel yielded the best reliability.
Aims:
The reliability and agreement between shear wave elastography (SWE) systems using differen... more Aims: The reliability and agreement between shear wave elastography (SWE) systems using different acquisition methods in muscles is not yet established. The objectives were to determine the reliability of a new SWE system on normal resting muscles using different acquisition methods and to compare its performance to an established state-of-the-art system.
Material and methods: Small, medium and large ROI sizes in addition to longitudinal, oblique and transverse orientations over five different locations within the rectus femoris muscle were tested using the new system. Results were compared to the established system to test for inter-system reproducibility.
Results: Lowest within-subject coefficient of variance (4.3%) and shear wave velocity (1.83 m/s) were associated with the medium ROI and longitudinal orientation from the lateral location. This combination resulted in a strong internal agreement of intra-class correlation of 0.76 (0.57–0.89) for the new system and an almost perfect agreement of 0.92 (0.82–0.97) for the established. Inter-system reproducibility for the best combination was 0.71 (0.48–1) with a mean velocity difference ±95% limits of agreement of 0.07±0.49 m/s.
Conclusions: Altering SWE acquisition methods can produce variable results. The new system produced reliable results that are comparable with but not as reliable as the established.
In recent years, imaging has played an increasing role in the clinical management of patients wit... more In recent years, imaging has played an increasing role in the clinical management of patients with rheumatic diseases with respect to aiding diagnosis, guiding therapy and monitoring disease progression. These roles have been underpinned by research which has enhanced our understanding of disease pathogenesis and pathophysiology of rheumatology conditions, in addition to their key role in outcome measurement in clinical trials. However, compared to joints, imaging research of muscles is less established, despite the fact that muscle symptoms are very common and debilitating in many rheumatic diseases. Recently, it has been shown that even though patients with rheumatoid arthritis may achieve clinical remission, defined by asymptomatic joints, many remain affected by lingering constitutional systemic symptoms like fatigue, tiredness, weakness and myalgia, which may be attributed to changes in the muscles. Recent improvements in imaging technology, coupled with an increasing clinical interest, has started to ignite new interest in the area. This perspective discusses the rationale for using imaging, particularly ultrasound and MRI, for investigating muscle pathology involved in common inflammatory rheumatic diseases. The muscles associated with rheumatic diseases can be affected in many ways, including myositis-an inflammatory muscle condition, and myopathy secondary to medications, such as glucocorticoids. In addition to non-invasive visual assessment of muscles in these conditions, novel imaging techniques like shear wave elastography and quantitative MRI can provide further useful information regarding the physiological and biomechanical status of the muscle.
Purpose:
To investigate the reproducibility of shear wave elastography (SWE) among operators, mac... more Purpose: To investigate the reproducibility of shear wave elastography (SWE) among operators, machines and probes in a phantom. Moreover, to evaluate the effect of depth and the accuracy of the embedded inclusions. Methods: In-vitro stiffness measurements of six inclusions (10kPa, 40kPa and 60kPa) embedded at two depths (1.5cm and 5cm) in an elastography phantom. The measurements obtained by two sonographers using two ultrasound machines; the SuperSonic Imagine Aixplorer using the XC6-1, SL10-2 and SL18-5 probes, and the General Electric LOGIQ E9 using the 9L-D probe. The variability was evaluated using the coefficient of variation. The reproducibility was calculated using an intraclass correlation coefficient (ICC). Results: For shallow inclusions, low variability was observed between the results obtained by each operator (range 0.9%–5.4%). However, the variability increased significantly in the deeper inclusions (range 2.4–80.8%). The measurement difference between the operators was 1%–15% in superficial inclusions and 3%–43% in deep inclusions. The inter-operator reproducibility was almost perfect (ICC>0.90). The measurement difference between the machines was 0–15% in superficial inclusions and 38.6%–82.9% in deep inclusions. In superficial inclusions, there was an excellent reproducibility between the three probes (ICC>0.97). On average, the means of the 10 kPa inclusions’ stiffness were overestimated by 16%, while those at 40 kPa and 60 kPa were underestimated by 42% and 48%, respectively. Conclusion: Phantom SWE measurements were reproducible between operators, machines and probes at superficial depths only. SWE measurements acquired in deep regions should not be used interchangeably between operators, machines or probes.
Objective
To determine inter- and intra-reader reproducibility of shear wave elastography measure... more Objective To determine inter- and intra-reader reproducibility of shear wave elastography measurements for musculoskeletal soft tissue masses.
Materials and methods In all, 64 patients with musculoskeletal soft tissue masses were scanned by two readers prior to biopsy; each taking five measurements of shear wave velocity (m/s) and stiffness (kPa). A single lesion per patient was scanned in transverse and cranio-caudal planes. Depth measurements (cm) and volume (cm3) were recorded for each lesion, for each reader. Linear mixed modelling was performed to assess limits of agreement (LOA), inter- and intra-reader repeatability, including analyses for measured depth and volume.
Results Of the 64 lesions scanned, 24 (38%) were malignant. Bland-Altman plots demonstrated negligible bias with wide LOA for all measurements. Transverse velocity was the most reliable measure—intraclass correlation (95% CI) = 0.917 (0.886, 1)—though reader 1 measures could be between 38% lower and 57% higher than reader 2 [ratio-scale bias (95% LOA) = 0.99 (0.64, 1.55)]. Repeatability coefficients indicated most disagreement resulted from poor within-reader reproducibility. LOA between readers calculated from means of five repeated measurements were narrower—transverse velocity ratio-scale bias (95% LOA) = 1.00 (0.74, 1.35). Depth affected both estimated velocity and repeatability; volume also affected repeatability.
Conclusion This study found poor repeatability of measurements with wide LOA due mostly to intra-reader variability. Transverse velocity was the most reliable measure; variability may be affected by lesion depth. At least five measurements should be reported with LOA to assist future comparability between shear wave elastography systems in evaluating soft tissue masses.
International Journal of Rheumatic Dsiseases, 2019
Aim
To investigate muscle stiffness changes in patients treated for giant cell arteritis (GCA) wi... more Aim To investigate muscle stiffness changes in patients treated for giant cell arteritis (GCA) with high‐dose oral glucocorticoids.
Methods Using ultrasound elastography, shear wave velocity (SWV) was measured in the quadriceps, hamstrings and biceps brachii muscles of 14 patients with GCA (4 male, mean age ± SD, 68.2 ± 4.3 years) within the first 2 weeks of initiating glucocorticoid treatment (baseline) and repeated after 3 and 6 months treatment. Muscle strength and performance tests were performed at each visit. Baseline measures were compared with those from 14 healthy controls. Linear mixed models were used to test for change in patient measures over time.
Results At baseline, muscle SWV in patients was not significantly different from controls. With glucocorticoid treatment, there was a reduction in SWV in the leg but not the arm muscles. SWV decreased by a mean of 14% (range 8.3%‐17.3%; P = .001) after 3 months and 18% (range 10.2%‐25.3%; P < .001) after 6‐months in the quadriceps and hamstrings during the resting position. The baseline, 3 and 6 months mean SWV (±SD) for the vastus lateralis were 1.62 ± 0.16 m/s, 1.40 ± 0.10 m/s and 1.31 ± 0.06 m/s, respectively (P < .001). In the patient group as a whole, there was no significant change in muscle strength. However, there were moderate correlations (r = .54‐.69) between exhibiting weaker muscle strength at follow‐up visits and a greater reduction in SWV.
Conclusion Glucocorticoid therapy in patients with GCA was associated with a significant reduction in proximal leg muscle stiffness during the first 6 months. Future research should study a larger sample of patients for a longer duration to investigate if diminished muscle stiffness precedes signs of glucocorticoid‐induced myopathy.
Objective:
To investigate muscle stiffness and strength in rheumatoid arthritis patients compare... more Objective: To investigate muscle stiffness and strength in rheumatoid arthritis patients compared to healthy controls.
Methods: A sample of 80 RA patients from three discrete groups: 1-newly diagnosed treatment-naïve RA (n = 29), 2-active RA for at least 1 year (n = 18) and 3-in remission RA for at least 1 year (n = 33), was compared to 40 healthy controls. Shear wave velocity (SWV) was measured using shear wave elastography as a surrogate for tissue stiffness in multiple muscles. All participants performed isometric grip strength, timed get-up-and-go test, 30-sec chair stand test and isokinetic knee extension/flexion(60°/sec). The difference in SWV amongst the groups was tested using one-way ANOVA, and the correlation between SWV and muscle strength results were calculated using Pearson’s coefficients.
Results: The mean age ± SD was 61.2 ± 12.8 for RA patients and 61.5 ± 10.5 years for controls. SWV was not significantly different amongst the groups on all muscles (p > 0.05). In comparison to controls, the new and active RA groups showed a significantly lower isokinetic strength by -29%(p = 0.013) and -28%(p = 0.040), fewer chair stands by -28%(p = 0.001) and -44%(p < 0.001), longer walking times by -25% (p = 0.025) and -30% (p = 0.001) respectively, and weaker grip strength by -45% for both (p < 0.001). The muscle strength in the remission RA groups was not significantly lower, except in the isokinetic knee strength (-21%; p = 0.027). The correlations between SWE and the muscle assessment results were weak and insignificant (r < 0.30; p > 0.05).
Conclusions: Significant muscle weakness was demonstrated in patients with RA disease. However, muscle stiffness was normal and not associated with muscle strength.
Objective
To investigate muscle stiffness in patients with idiopathic inflammatory myopathies (II... more Objective To investigate muscle stiffness in patients with idiopathic inflammatory myopathies (IIM) using shear wave elastography (SWE) and to correlate the results with muscle strength and MRI features of myositis.
Materials and methods Muscle shear wave velocity (SWV) was measured in 23 active IIM patients (13 females, mean age 50.4 ± 16.1 years) and 23 matched healthy controls (13 females, mean age 50.7 ± 16.2 years). The investigated muscles included the vastus lateralis (VL), rectus femoris (RF), vastus medialis (VM) vastus intermedius (VI), biceps femoris (BF), semitendinosus (ST), semimembranosus (SM) and the biceps brachii (BB) scanned during relaxed resting and passive stretching positions. Participants performed multiple tests to evaluate their muscle strength. IIM patients had a thigh MRI to assess degrees of oedema, fatty infiltration and atrophy.
Results In the resting position, IIM patients had a 12.9–22.2% significantly lower SWV (p < 0.05) for the quadriceps and hamstrings, but not BB. There was no difference during passive stretching. The SWV for VL, VI and BF showed moderate correlations with the muscle strength tests ranging from r = 0.47 to r = 0.70 (all p < 0.05). Lower SWV was associated with greater MRI scores of oedema (p = 0.001) and atrophy (p = 0.006). However, SWV did not correlate with fatty infiltration (r < 0.3; p = 0.28), creatine kinase (r = 0.28; p = 0.19) or disease duration (r = 0.26; p = 0.24).
Conclusion Shear wave elastography may detect abnormal reduced thigh stiffness in IIM patients. SWE measurements were significantly associated with muscle weakness and MRI signs of oedema and atrophy. Future research should investigate this new technology for monitoring disease activity.
Background:
Skeletal muscle undergoes structural changes with ageing which may alter its biomecha... more Background: Skeletal muscle undergoes structural changes with ageing which may alter its biomechanical properties. Shear wave elastography (SWE) may detect these changes by measuring muscle stiffness.
Aims: To investigate muscle stiffness in healthy young, middle-aged and elderly cohorts using SWE and correlate it with muscle strength and mass.
Methods: Shear wave velocity (SWV) was measured in the quadriceps, hamstrings and biceps brachii of 26 young (range 20–35 years), 21 middle-aged (40–55) and 30 elderly (77–94) volunteers. The participants performed several muscle tests to evaluate their strength. The One-way ANOVA was used to test the muscle stiffness differences between the groups and the Pearson’s correlation coefficient to evaluate the relationship between SWV and muscle strength.
Results: The overall resting muscle SWV gradually decreased with age but was only significantly reduced in the elderly group (p < 0.001); with the exception of the vastus lateralis SWV where a significant difference was noted (p < 0.05) between young (1.77 m/s), middle-aged (1.64 m/s) and elderly (1.48 m/s). The elderly group had on average 16.5% lower muscle stiffness compared to the young. SWV significantly correlated with muscle mass (r = 0.316), walking time (r = − 0.560), number of chair stands (r = 0.522), handgrip strength (r = 0.436) and isokinetic knee strength (r = 0.640). Sex and BMI did not explain any significant variation in SWV.
Conclusions: Ageing was associated with a decline in skeletal muscle stiffness which positively correlates with muscle weakness. Further research is needed to evaluate the promising role of SWE as a biomarker for sarcopenia assessment and potential falls risk prediction in elderly individuals.
Purpose:
To examine if shear-wave elastography (SWE) improves the accuracy of diagnosing soft-ti... more Purpose: To examine if shear-wave elastography (SWE) improves the accuracy of diagnosing soft-tissue masses as benign or malignant compared with US alone or in combination with MRI.
Materials and Methods: Two hundred six consecutive adult participants (mean age, 57.7 years; range, 18–91 years), including 89 men (median age, 56.0 years; range, 21–91 years) and 117 women (median age, 59.1 years; range, 18–88 years), who were referred for biopsy of a soft-tissue mass were prospectively recruited from December 2015 through March 2017. Participants underwent B-mode US, MRI, and SWE prior to biopsy. Three musculoskeletal radiologists independently reviewed US images alone, followed by US and MRI images together, and classified lesions as benign, probably benign, probably malignant, or malignant. For SWE, the area under the receiver operating characteristic (ROC) curve (AUC) was calculated for transverse shear-wave velocity (SWV). Multivariable logistic regression was used to investigate the association between SWE and malignancy alongside individual demographic and imaging variables.
Results: At histologic examination, 79 of 206 (38%) participants had malignant lesions. SWV showed good diagnostic accuracy for lesions classified as benign or probably benign by US alone (AUC = 0.87 [95% confidence interval {CI}: 0.79, 0.95]). SWV did not provide substantive diagnostic information for lesions classified as probably malignant or malignant, whether the classification was made with or without MRI. However, multivariable modeling indicated that diagnostic accuracy may vary by lesion position (interaction P = .02; superficial, odds ratio [OR] = 17.7 [95% CI: 1.50, 207], P = .02; deep/mixed, OR = 0.24 [95% CI: 0.07, 0.86], P = .03) and participant age (interaction P = .01; eg, age 43 years, OR = 0.72 [95% CI: 0.15, 3.5], P = .69; age 72 years, OR = 0.08 [95% CI: 0.02, 0.37], P = .001).
Conclusion: Shear-wave elastography can increase accuracy of soft-tissue lesion diagnosis in conjunction with US. However, a single cut-off may not be universally applicable with diagnostic accuracy that is affected by lesion position and patient age.
Purpose:
There is currently no standardized method for muscle shear wave elastography (SWE). The... more Purpose: There is currently no standardized method for muscle shear wave elastography (SWE). The objective of this study was to investigate the effect of unit of measurement, depth, and probe load on the reliability of muscle SWE.
Methods: The vastus lateralis, biceps femoris, biceps brachii, and abductor digiti minimi muscles were scanned on 20 healthy participants. The SWE readings were measured in shear wave velocity (m/s) and Young’s modulus (kPa). Three acquisitions of varying depths were acquired from vastus lateralis. Minimal probe load was compared with the use of a standoff gel layer. Three repeated measurements were acquired to assess reliability using intraclass correlations (ICC).
Results: The mean elasticity varied across muscle groups and ranged from 1.54 m/s for biceps femoris to 2.55 m/s for abductor digiti minimi (difference51.01 m/s [95% confidence interval, CI 0.92, 1.10]). Reporting readings in meters per second resulted in higher ICC of 0.83 (0.65, 0.93) in comparison to 0.77 (0.52, 0.90) for kilopascal for the vastus lateralis muscle only. Variance increased proportionally with depth reaching 0.17 (equivalent to 60.82 m/s) at 6 cm. Using a standoff gel decreased ICC to 0.63 (0.20, 0.84) despite similar mean elasticity readings to minimal probe load.
Conclusions: Different acquisition and technical factors may significantly affect the reliability of SWE in skeletal muscles. Readings acquired in the unit of shear wave velocity (m/s) from depths less than 4 cm using a minimal probe load without a standoff gel yielded the best reliability.
Aims:
The reliability and agreement between shear wave elastography (SWE) systems using differen... more Aims: The reliability and agreement between shear wave elastography (SWE) systems using different acquisition methods in muscles is not yet established. The objectives were to determine the reliability of a new SWE system on normal resting muscles using different acquisition methods and to compare its performance to an established state-of-the-art system.
Material and methods: Small, medium and large ROI sizes in addition to longitudinal, oblique and transverse orientations over five different locations within the rectus femoris muscle were tested using the new system. Results were compared to the established system to test for inter-system reproducibility.
Results: Lowest within-subject coefficient of variance (4.3%) and shear wave velocity (1.83 m/s) were associated with the medium ROI and longitudinal orientation from the lateral location. This combination resulted in a strong internal agreement of intra-class correlation of 0.76 (0.57–0.89) for the new system and an almost perfect agreement of 0.92 (0.82–0.97) for the established. Inter-system reproducibility for the best combination was 0.71 (0.48–1) with a mean velocity difference ±95% limits of agreement of 0.07±0.49 m/s.
Conclusions: Altering SWE acquisition methods can produce variable results. The new system produced reliable results that are comparable with but not as reliable as the established.
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Papers by Abdulrahman Alfuraih
To investigate the reproducibility of shear wave elastography (SWE) among operators, machines and probes in a phantom. Moreover, to evaluate the effect of depth and the accuracy of the embedded inclusions.
Methods:
In-vitro stiffness measurements of six inclusions (10kPa, 40kPa and 60kPa) embedded at two depths (1.5cm and 5cm) in an elastography phantom. The measurements obtained by two sonographers using two ultrasound machines; the SuperSonic Imagine Aixplorer using the XC6-1, SL10-2 and SL18-5 probes, and the General Electric LOGIQ E9 using the 9L-D probe. The variability was evaluated using the coefficient of variation. The reproducibility was calculated using an intraclass correlation coefficient (ICC).
Results:
For shallow inclusions, low variability was observed between the results obtained by each operator (range 0.9%–5.4%). However, the variability increased significantly in the deeper inclusions (range 2.4–80.8%). The measurement difference between the operators was 1%–15% in superficial inclusions and 3%–43% in deep inclusions. The inter-operator reproducibility was almost perfect (ICC>0.90). The measurement difference between the machines was 0–15% in superficial inclusions and 38.6%–82.9% in deep inclusions. In superficial inclusions, there was an excellent reproducibility between the three probes (ICC>0.97). On average, the means of the 10 kPa inclusions’ stiffness were overestimated by 16%, while those at 40 kPa and 60 kPa were underestimated by 42% and 48%, respectively.
Conclusion:
Phantom SWE measurements were reproducible between operators, machines and probes at superficial depths only. SWE measurements acquired in deep regions should not be used interchangeably between operators, machines or probes.
To determine inter- and intra-reader reproducibility of shear wave elastography measurements for musculoskeletal soft tissue masses.
Materials and methods
In all, 64 patients with musculoskeletal soft tissue masses were scanned by two readers prior to biopsy; each taking five measurements of shear wave velocity (m/s) and stiffness (kPa). A single lesion per patient was scanned in transverse and cranio-caudal planes. Depth measurements (cm) and volume (cm3) were recorded for each lesion, for each reader. Linear mixed modelling was performed to assess limits of agreement (LOA), inter- and intra-reader repeatability, including analyses for measured depth and volume.
Results
Of the 64 lesions scanned, 24 (38%) were malignant. Bland-Altman plots demonstrated negligible bias with wide LOA for all measurements. Transverse velocity was the most reliable measure—intraclass correlation (95% CI) = 0.917 (0.886, 1)—though reader 1 measures could be between 38% lower and 57% higher than reader 2 [ratio-scale bias (95% LOA) = 0.99 (0.64, 1.55)]. Repeatability coefficients indicated most disagreement resulted from poor within-reader reproducibility. LOA between readers calculated from means of five repeated measurements were narrower—transverse velocity ratio-scale bias (95% LOA) = 1.00 (0.74, 1.35). Depth affected both estimated velocity and repeatability; volume also affected repeatability.
Conclusion
This study found poor repeatability of measurements with wide LOA due mostly to intra-reader variability. Transverse velocity was the most reliable measure; variability may be affected by lesion depth. At least five measurements should be reported with LOA to assist future comparability between shear wave elastography systems in evaluating soft tissue masses.
To investigate muscle stiffness changes in patients treated for giant cell arteritis (GCA) with high‐dose oral glucocorticoids.
Methods
Using ultrasound elastography, shear wave velocity (SWV) was measured in the quadriceps, hamstrings and biceps brachii muscles of 14 patients with GCA (4 male, mean age ± SD, 68.2 ± 4.3 years) within the first 2 weeks of initiating glucocorticoid treatment (baseline) and repeated after 3 and 6 months treatment. Muscle strength and performance tests were performed at each visit. Baseline measures were compared with those from 14 healthy controls. Linear mixed models were used to test for change in patient measures over time.
Results
At baseline, muscle SWV in patients was not significantly different from controls. With glucocorticoid treatment, there was a reduction in SWV in the leg but not the arm muscles. SWV decreased by a mean of 14% (range 8.3%‐17.3%; P = .001) after 3 months and 18% (range 10.2%‐25.3%; P < .001) after 6‐months in the quadriceps and hamstrings during the resting position. The baseline, 3 and 6 months mean SWV (±SD) for the vastus lateralis were 1.62 ± 0.16 m/s, 1.40 ± 0.10 m/s and 1.31 ± 0.06 m/s, respectively (P < .001). In the patient group as a whole, there was no significant change in muscle strength. However, there were moderate correlations (r = .54‐.69) between exhibiting weaker muscle strength at follow‐up visits and a greater reduction in SWV.
Conclusion
Glucocorticoid therapy in patients with GCA was associated with a significant reduction in proximal leg muscle stiffness during the first 6 months. Future research should study a larger sample of patients for a longer duration to investigate if diminished muscle stiffness precedes signs of glucocorticoid‐induced myopathy.
To investigate muscle stiffness and strength in rheumatoid arthritis patients compared to healthy controls.
Methods:
A sample of 80 RA patients from three discrete groups: 1-newly diagnosed treatment-naïve RA (n = 29), 2-active RA for at least 1 year (n = 18) and 3-in remission RA for at least 1 year (n = 33), was compared to 40 healthy controls. Shear wave velocity (SWV) was measured using shear wave elastography as a surrogate for tissue stiffness in multiple muscles. All participants performed isometric grip strength, timed get-up-and-go test, 30-sec chair stand test and isokinetic knee extension/flexion(60°/sec). The difference in SWV amongst the groups was tested using one-way ANOVA, and the correlation between SWV and muscle strength results were calculated using Pearson’s coefficients.
Results:
The mean age ± SD was 61.2 ± 12.8 for RA patients and 61.5 ± 10.5 years for controls. SWV was not significantly different amongst the groups on all muscles (p > 0.05). In comparison to controls, the new and active RA groups showed a significantly lower isokinetic strength by -29%(p = 0.013) and -28%(p = 0.040), fewer chair stands by -28%(p = 0.001) and -44%(p < 0.001), longer walking times by -25% (p = 0.025) and -30% (p = 0.001) respectively, and weaker grip strength by -45% for both (p < 0.001). The muscle strength in the remission RA groups was not significantly lower, except in the isokinetic knee strength (-21%; p = 0.027). The correlations between SWE and the muscle assessment results were weak and insignificant (r < 0.30; p > 0.05).
Conclusions:
Significant muscle weakness was demonstrated in patients with RA disease. However, muscle stiffness was normal and not associated with muscle strength.
To investigate muscle stiffness in patients with idiopathic inflammatory myopathies (IIM) using shear wave elastography (SWE) and to correlate the results with muscle strength and MRI features of myositis.
Materials and methods
Muscle shear wave velocity (SWV) was measured in 23 active IIM patients (13 females, mean age 50.4 ± 16.1 years) and 23 matched healthy controls (13 females, mean age 50.7 ± 16.2 years). The investigated muscles included the vastus lateralis (VL), rectus femoris (RF), vastus medialis (VM) vastus intermedius (VI), biceps femoris (BF), semitendinosus (ST), semimembranosus (SM) and the biceps brachii (BB) scanned during relaxed resting and passive stretching positions. Participants performed multiple tests to evaluate their muscle strength. IIM patients had a thigh MRI to assess degrees of oedema, fatty infiltration and atrophy.
Results
In the resting position, IIM patients had a 12.9–22.2% significantly lower SWV (p < 0.05) for the quadriceps and hamstrings, but not BB. There was no difference during passive stretching. The SWV for VL, VI and BF showed moderate correlations with the muscle strength tests ranging from r = 0.47 to r = 0.70 (all p < 0.05). Lower SWV was associated with greater MRI scores of oedema (p = 0.001) and atrophy (p = 0.006). However, SWV did not correlate with fatty infiltration (r < 0.3; p = 0.28), creatine kinase (r = 0.28; p = 0.19) or disease duration (r = 0.26; p = 0.24).
Conclusion
Shear wave elastography may detect abnormal reduced thigh stiffness in IIM patients. SWE measurements were significantly associated with muscle weakness and MRI signs of oedema and atrophy. Future research should investigate this new technology for monitoring disease activity.
Skeletal muscle undergoes structural changes with ageing which may alter its biomechanical properties. Shear wave elastography (SWE) may detect these changes by measuring muscle stiffness.
Aims:
To investigate muscle stiffness in healthy young, middle-aged and elderly cohorts using SWE and correlate it with muscle strength and mass.
Methods:
Shear wave velocity (SWV) was measured in the quadriceps, hamstrings and biceps brachii of 26 young (range 20–35 years), 21 middle-aged (40–55) and 30 elderly (77–94) volunteers. The participants performed several muscle tests to evaluate their strength. The One-way ANOVA was used to test the muscle stiffness differences between the groups and the Pearson’s correlation coefficient to evaluate the relationship between SWV and muscle strength.
Results:
The overall resting muscle SWV gradually decreased with age but was only significantly reduced in the elderly group (p < 0.001); with the exception of the vastus lateralis SWV where a significant difference was noted (p < 0.05) between young (1.77 m/s), middle-aged (1.64 m/s) and elderly (1.48 m/s). The elderly group had on average 16.5% lower muscle stiffness compared to the young. SWV significantly correlated with muscle mass (r = 0.316), walking time (r = − 0.560), number of chair stands (r = 0.522), handgrip strength (r = 0.436) and isokinetic knee strength (r = 0.640). Sex and BMI did not explain any significant variation in SWV.
Conclusions:
Ageing was associated with a decline in skeletal muscle stiffness which positively correlates with muscle weakness. Further research is needed to evaluate the promising role of SWE as a biomarker for sarcopenia assessment and potential falls risk prediction in elderly individuals.
To examine if shear-wave elastography (SWE) improves the accuracy of diagnosing soft-tissue masses as benign or malignant compared with US alone or in combination with MRI.
Materials and Methods:
Two hundred six consecutive adult participants (mean age, 57.7 years; range, 18–91 years), including 89 men (median age, 56.0 years; range, 21–91 years) and 117 women (median age, 59.1 years; range, 18–88 years), who were referred for biopsy of a soft-tissue mass were prospectively recruited from December 2015 through March 2017. Participants underwent B-mode US, MRI, and SWE prior to biopsy. Three musculoskeletal radiologists independently reviewed US images alone, followed by US and MRI images together, and classified lesions as benign, probably benign, probably malignant, or malignant. For SWE, the area under the receiver operating characteristic (ROC) curve (AUC) was calculated for transverse shear-wave velocity (SWV). Multivariable logistic regression was used to investigate the association between SWE and malignancy alongside individual demographic and imaging variables.
Results:
At histologic examination, 79 of 206 (38%) participants had malignant lesions. SWV showed good diagnostic accuracy for lesions classified as benign or probably benign by US alone (AUC = 0.87 [95% confidence interval {CI}: 0.79, 0.95]). SWV did not provide substantive diagnostic information for lesions classified as probably malignant or malignant, whether the classification was made with or without MRI. However, multivariable modeling indicated that diagnostic accuracy may vary by lesion position (interaction P = .02; superficial, odds ratio [OR] = 17.7 [95% CI: 1.50, 207], P = .02; deep/mixed, OR = 0.24 [95% CI: 0.07, 0.86], P = .03) and participant age (interaction P = .01; eg, age 43 years, OR = 0.72 [95% CI: 0.15, 3.5], P = .69; age 72 years, OR = 0.08 [95% CI: 0.02, 0.37], P = .001).
Conclusion:
Shear-wave elastography can increase accuracy of soft-tissue lesion diagnosis in conjunction with US. However, a single cut-off may not be universally applicable with diagnostic accuracy that is affected by lesion position and patient age.
There is currently no standardized method for muscle shear wave elastography (SWE). The objective of this study was to investigate the effect of unit of measurement, depth, and probe load on the reliability of muscle SWE.
Methods:
The vastus lateralis, biceps femoris, biceps brachii, and abductor digiti minimi muscles were scanned on 20 healthy participants. The SWE readings were measured in shear wave velocity (m/s) and Young’s modulus (kPa). Three acquisitions of varying depths were acquired from vastus lateralis. Minimal probe load was compared with the use of a standoff gel layer. Three repeated measurements were acquired to assess reliability using intraclass correlations (ICC).
Results:
The mean elasticity varied across muscle groups and ranged from 1.54 m/s for biceps femoris to 2.55 m/s for abductor digiti minimi (difference51.01 m/s [95% confidence interval, CI 0.92, 1.10]). Reporting readings in meters per second resulted in higher ICC of 0.83 (0.65, 0.93) in comparison to 0.77 (0.52, 0.90) for kilopascal for the vastus lateralis muscle only. Variance increased proportionally with depth reaching 0.17 (equivalent to 60.82 m/s) at 6 cm. Using a standoff gel decreased ICC to 0.63 (0.20, 0.84) despite similar mean elasticity readings to minimal probe load.
Conclusions:
Different acquisition and technical factors may significantly affect the reliability of SWE in skeletal muscles. Readings acquired in the unit of shear wave velocity (m/s) from depths less than 4 cm using a minimal probe load without a standoff gel yielded the best reliability.
The reliability and agreement between shear wave elastography (SWE) systems using different acquisition methods in muscles is not yet established. The objectives were to determine the reliability of a new SWE system on normal resting muscles using different acquisition methods and to compare its performance to an established state-of-the-art system.
Material and methods:
Small, medium and large ROI sizes in addition to longitudinal, oblique and transverse orientations over five different locations within the rectus femoris muscle were tested using the new system. Results were compared to the established system to test for inter-system reproducibility.
Results: Lowest within-subject coefficient of variance (4.3%) and shear wave velocity (1.83 m/s) were associated with the medium ROI and longitudinal orientation from the lateral location. This combination resulted in a strong internal agreement of intra-class correlation of 0.76 (0.57–0.89) for the new system and an almost perfect agreement of 0.92 (0.82–0.97) for the established. Inter-system reproducibility for the best combination was 0.71 (0.48–1) with a mean velocity difference ±95% limits of agreement of 0.07±0.49 m/s.
Conclusions:
Altering SWE acquisition methods can produce variable results. The new system produced reliable results that are comparable with but not as reliable as the established.
To investigate the reproducibility of shear wave elastography (SWE) among operators, machines and probes in a phantom. Moreover, to evaluate the effect of depth and the accuracy of the embedded inclusions.
Methods:
In-vitro stiffness measurements of six inclusions (10kPa, 40kPa and 60kPa) embedded at two depths (1.5cm and 5cm) in an elastography phantom. The measurements obtained by two sonographers using two ultrasound machines; the SuperSonic Imagine Aixplorer using the XC6-1, SL10-2 and SL18-5 probes, and the General Electric LOGIQ E9 using the 9L-D probe. The variability was evaluated using the coefficient of variation. The reproducibility was calculated using an intraclass correlation coefficient (ICC).
Results:
For shallow inclusions, low variability was observed between the results obtained by each operator (range 0.9%–5.4%). However, the variability increased significantly in the deeper inclusions (range 2.4–80.8%). The measurement difference between the operators was 1%–15% in superficial inclusions and 3%–43% in deep inclusions. The inter-operator reproducibility was almost perfect (ICC>0.90). The measurement difference between the machines was 0–15% in superficial inclusions and 38.6%–82.9% in deep inclusions. In superficial inclusions, there was an excellent reproducibility between the three probes (ICC>0.97). On average, the means of the 10 kPa inclusions’ stiffness were overestimated by 16%, while those at 40 kPa and 60 kPa were underestimated by 42% and 48%, respectively.
Conclusion:
Phantom SWE measurements were reproducible between operators, machines and probes at superficial depths only. SWE measurements acquired in deep regions should not be used interchangeably between operators, machines or probes.
To determine inter- and intra-reader reproducibility of shear wave elastography measurements for musculoskeletal soft tissue masses.
Materials and methods
In all, 64 patients with musculoskeletal soft tissue masses were scanned by two readers prior to biopsy; each taking five measurements of shear wave velocity (m/s) and stiffness (kPa). A single lesion per patient was scanned in transverse and cranio-caudal planes. Depth measurements (cm) and volume (cm3) were recorded for each lesion, for each reader. Linear mixed modelling was performed to assess limits of agreement (LOA), inter- and intra-reader repeatability, including analyses for measured depth and volume.
Results
Of the 64 lesions scanned, 24 (38%) were malignant. Bland-Altman plots demonstrated negligible bias with wide LOA for all measurements. Transverse velocity was the most reliable measure—intraclass correlation (95% CI) = 0.917 (0.886, 1)—though reader 1 measures could be between 38% lower and 57% higher than reader 2 [ratio-scale bias (95% LOA) = 0.99 (0.64, 1.55)]. Repeatability coefficients indicated most disagreement resulted from poor within-reader reproducibility. LOA between readers calculated from means of five repeated measurements were narrower—transverse velocity ratio-scale bias (95% LOA) = 1.00 (0.74, 1.35). Depth affected both estimated velocity and repeatability; volume also affected repeatability.
Conclusion
This study found poor repeatability of measurements with wide LOA due mostly to intra-reader variability. Transverse velocity was the most reliable measure; variability may be affected by lesion depth. At least five measurements should be reported with LOA to assist future comparability between shear wave elastography systems in evaluating soft tissue masses.
To investigate muscle stiffness changes in patients treated for giant cell arteritis (GCA) with high‐dose oral glucocorticoids.
Methods
Using ultrasound elastography, shear wave velocity (SWV) was measured in the quadriceps, hamstrings and biceps brachii muscles of 14 patients with GCA (4 male, mean age ± SD, 68.2 ± 4.3 years) within the first 2 weeks of initiating glucocorticoid treatment (baseline) and repeated after 3 and 6 months treatment. Muscle strength and performance tests were performed at each visit. Baseline measures were compared with those from 14 healthy controls. Linear mixed models were used to test for change in patient measures over time.
Results
At baseline, muscle SWV in patients was not significantly different from controls. With glucocorticoid treatment, there was a reduction in SWV in the leg but not the arm muscles. SWV decreased by a mean of 14% (range 8.3%‐17.3%; P = .001) after 3 months and 18% (range 10.2%‐25.3%; P < .001) after 6‐months in the quadriceps and hamstrings during the resting position. The baseline, 3 and 6 months mean SWV (±SD) for the vastus lateralis were 1.62 ± 0.16 m/s, 1.40 ± 0.10 m/s and 1.31 ± 0.06 m/s, respectively (P < .001). In the patient group as a whole, there was no significant change in muscle strength. However, there were moderate correlations (r = .54‐.69) between exhibiting weaker muscle strength at follow‐up visits and a greater reduction in SWV.
Conclusion
Glucocorticoid therapy in patients with GCA was associated with a significant reduction in proximal leg muscle stiffness during the first 6 months. Future research should study a larger sample of patients for a longer duration to investigate if diminished muscle stiffness precedes signs of glucocorticoid‐induced myopathy.
To investigate muscle stiffness and strength in rheumatoid arthritis patients compared to healthy controls.
Methods:
A sample of 80 RA patients from three discrete groups: 1-newly diagnosed treatment-naïve RA (n = 29), 2-active RA for at least 1 year (n = 18) and 3-in remission RA for at least 1 year (n = 33), was compared to 40 healthy controls. Shear wave velocity (SWV) was measured using shear wave elastography as a surrogate for tissue stiffness in multiple muscles. All participants performed isometric grip strength, timed get-up-and-go test, 30-sec chair stand test and isokinetic knee extension/flexion(60°/sec). The difference in SWV amongst the groups was tested using one-way ANOVA, and the correlation between SWV and muscle strength results were calculated using Pearson’s coefficients.
Results:
The mean age ± SD was 61.2 ± 12.8 for RA patients and 61.5 ± 10.5 years for controls. SWV was not significantly different amongst the groups on all muscles (p > 0.05). In comparison to controls, the new and active RA groups showed a significantly lower isokinetic strength by -29%(p = 0.013) and -28%(p = 0.040), fewer chair stands by -28%(p = 0.001) and -44%(p < 0.001), longer walking times by -25% (p = 0.025) and -30% (p = 0.001) respectively, and weaker grip strength by -45% for both (p < 0.001). The muscle strength in the remission RA groups was not significantly lower, except in the isokinetic knee strength (-21%; p = 0.027). The correlations between SWE and the muscle assessment results were weak and insignificant (r < 0.30; p > 0.05).
Conclusions:
Significant muscle weakness was demonstrated in patients with RA disease. However, muscle stiffness was normal and not associated with muscle strength.
To investigate muscle stiffness in patients with idiopathic inflammatory myopathies (IIM) using shear wave elastography (SWE) and to correlate the results with muscle strength and MRI features of myositis.
Materials and methods
Muscle shear wave velocity (SWV) was measured in 23 active IIM patients (13 females, mean age 50.4 ± 16.1 years) and 23 matched healthy controls (13 females, mean age 50.7 ± 16.2 years). The investigated muscles included the vastus lateralis (VL), rectus femoris (RF), vastus medialis (VM) vastus intermedius (VI), biceps femoris (BF), semitendinosus (ST), semimembranosus (SM) and the biceps brachii (BB) scanned during relaxed resting and passive stretching positions. Participants performed multiple tests to evaluate their muscle strength. IIM patients had a thigh MRI to assess degrees of oedema, fatty infiltration and atrophy.
Results
In the resting position, IIM patients had a 12.9–22.2% significantly lower SWV (p < 0.05) for the quadriceps and hamstrings, but not BB. There was no difference during passive stretching. The SWV for VL, VI and BF showed moderate correlations with the muscle strength tests ranging from r = 0.47 to r = 0.70 (all p < 0.05). Lower SWV was associated with greater MRI scores of oedema (p = 0.001) and atrophy (p = 0.006). However, SWV did not correlate with fatty infiltration (r < 0.3; p = 0.28), creatine kinase (r = 0.28; p = 0.19) or disease duration (r = 0.26; p = 0.24).
Conclusion
Shear wave elastography may detect abnormal reduced thigh stiffness in IIM patients. SWE measurements were significantly associated with muscle weakness and MRI signs of oedema and atrophy. Future research should investigate this new technology for monitoring disease activity.
Skeletal muscle undergoes structural changes with ageing which may alter its biomechanical properties. Shear wave elastography (SWE) may detect these changes by measuring muscle stiffness.
Aims:
To investigate muscle stiffness in healthy young, middle-aged and elderly cohorts using SWE and correlate it with muscle strength and mass.
Methods:
Shear wave velocity (SWV) was measured in the quadriceps, hamstrings and biceps brachii of 26 young (range 20–35 years), 21 middle-aged (40–55) and 30 elderly (77–94) volunteers. The participants performed several muscle tests to evaluate their strength. The One-way ANOVA was used to test the muscle stiffness differences between the groups and the Pearson’s correlation coefficient to evaluate the relationship between SWV and muscle strength.
Results:
The overall resting muscle SWV gradually decreased with age but was only significantly reduced in the elderly group (p < 0.001); with the exception of the vastus lateralis SWV where a significant difference was noted (p < 0.05) between young (1.77 m/s), middle-aged (1.64 m/s) and elderly (1.48 m/s). The elderly group had on average 16.5% lower muscle stiffness compared to the young. SWV significantly correlated with muscle mass (r = 0.316), walking time (r = − 0.560), number of chair stands (r = 0.522), handgrip strength (r = 0.436) and isokinetic knee strength (r = 0.640). Sex and BMI did not explain any significant variation in SWV.
Conclusions:
Ageing was associated with a decline in skeletal muscle stiffness which positively correlates with muscle weakness. Further research is needed to evaluate the promising role of SWE as a biomarker for sarcopenia assessment and potential falls risk prediction in elderly individuals.
To examine if shear-wave elastography (SWE) improves the accuracy of diagnosing soft-tissue masses as benign or malignant compared with US alone or in combination with MRI.
Materials and Methods:
Two hundred six consecutive adult participants (mean age, 57.7 years; range, 18–91 years), including 89 men (median age, 56.0 years; range, 21–91 years) and 117 women (median age, 59.1 years; range, 18–88 years), who were referred for biopsy of a soft-tissue mass were prospectively recruited from December 2015 through March 2017. Participants underwent B-mode US, MRI, and SWE prior to biopsy. Three musculoskeletal radiologists independently reviewed US images alone, followed by US and MRI images together, and classified lesions as benign, probably benign, probably malignant, or malignant. For SWE, the area under the receiver operating characteristic (ROC) curve (AUC) was calculated for transverse shear-wave velocity (SWV). Multivariable logistic regression was used to investigate the association between SWE and malignancy alongside individual demographic and imaging variables.
Results:
At histologic examination, 79 of 206 (38%) participants had malignant lesions. SWV showed good diagnostic accuracy for lesions classified as benign or probably benign by US alone (AUC = 0.87 [95% confidence interval {CI}: 0.79, 0.95]). SWV did not provide substantive diagnostic information for lesions classified as probably malignant or malignant, whether the classification was made with or without MRI. However, multivariable modeling indicated that diagnostic accuracy may vary by lesion position (interaction P = .02; superficial, odds ratio [OR] = 17.7 [95% CI: 1.50, 207], P = .02; deep/mixed, OR = 0.24 [95% CI: 0.07, 0.86], P = .03) and participant age (interaction P = .01; eg, age 43 years, OR = 0.72 [95% CI: 0.15, 3.5], P = .69; age 72 years, OR = 0.08 [95% CI: 0.02, 0.37], P = .001).
Conclusion:
Shear-wave elastography can increase accuracy of soft-tissue lesion diagnosis in conjunction with US. However, a single cut-off may not be universally applicable with diagnostic accuracy that is affected by lesion position and patient age.
There is currently no standardized method for muscle shear wave elastography (SWE). The objective of this study was to investigate the effect of unit of measurement, depth, and probe load on the reliability of muscle SWE.
Methods:
The vastus lateralis, biceps femoris, biceps brachii, and abductor digiti minimi muscles were scanned on 20 healthy participants. The SWE readings were measured in shear wave velocity (m/s) and Young’s modulus (kPa). Three acquisitions of varying depths were acquired from vastus lateralis. Minimal probe load was compared with the use of a standoff gel layer. Three repeated measurements were acquired to assess reliability using intraclass correlations (ICC).
Results:
The mean elasticity varied across muscle groups and ranged from 1.54 m/s for biceps femoris to 2.55 m/s for abductor digiti minimi (difference51.01 m/s [95% confidence interval, CI 0.92, 1.10]). Reporting readings in meters per second resulted in higher ICC of 0.83 (0.65, 0.93) in comparison to 0.77 (0.52, 0.90) for kilopascal for the vastus lateralis muscle only. Variance increased proportionally with depth reaching 0.17 (equivalent to 60.82 m/s) at 6 cm. Using a standoff gel decreased ICC to 0.63 (0.20, 0.84) despite similar mean elasticity readings to minimal probe load.
Conclusions:
Different acquisition and technical factors may significantly affect the reliability of SWE in skeletal muscles. Readings acquired in the unit of shear wave velocity (m/s) from depths less than 4 cm using a minimal probe load without a standoff gel yielded the best reliability.
The reliability and agreement between shear wave elastography (SWE) systems using different acquisition methods in muscles is not yet established. The objectives were to determine the reliability of a new SWE system on normal resting muscles using different acquisition methods and to compare its performance to an established state-of-the-art system.
Material and methods:
Small, medium and large ROI sizes in addition to longitudinal, oblique and transverse orientations over five different locations within the rectus femoris muscle were tested using the new system. Results were compared to the established system to test for inter-system reproducibility.
Results: Lowest within-subject coefficient of variance (4.3%) and shear wave velocity (1.83 m/s) were associated with the medium ROI and longitudinal orientation from the lateral location. This combination resulted in a strong internal agreement of intra-class correlation of 0.76 (0.57–0.89) for the new system and an almost perfect agreement of 0.92 (0.82–0.97) for the established. Inter-system reproducibility for the best combination was 0.71 (0.48–1) with a mean velocity difference ±95% limits of agreement of 0.07±0.49 m/s.
Conclusions:
Altering SWE acquisition methods can produce variable results. The new system produced reliable results that are comparable with but not as reliable as the established.