A systematic investigation of feasible acoustic windows and the impact of myocardial anisotropy for in vivo human cardiac shear wave elastography

Shear wave elastography (SWE) is a type of ultrasound elastography with which the elastic properties of breast tissues can be quantitatively assessed. The purpose of this study was to determine the impact of different regions of interest (ROI) and lesion size on the performance of SWE in differentiating malignant breast lesions. The study included 150 female patients with histopathologically confirmed malignant breast lesions. Minimal (Emin), mean (Emean), maximal (Emax) elastic modulus and elasticity ratio (e-ratio) values were measured using a circular ROI size of 2, 4 and 6 mm diameters and the lesions were divided into large (diameter ≥ 15 mm) and small (diameter < 15 mm). Highest Emin, Emean and e-ratio values and lowest variability were observed when using the 2 mm ROI. Emax values did not differ between different ROI sizes. Larger lesions had significantly higher Emean and Emax values, but there was no difference in e-ratio values between lesions of different sizes. In conclusion, when measuring the Emin, Emean and e-ratio of malignant breast lesions using SWE the smallest possible ROI size should be used regardless of lesion size. ROI size has no impact on Emax values while lesion size has no impact on e-ratio values.

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Feasibility of Reverberant Shear Wave Elastography for In Vivo Assessment of Skeletal Muscle Viscoelasticity

2020 IEEE International Ultrasonics Symposium (IUS) ◽

10.1109/ius46767.2020.9251504 ◽

2020 ◽

Author(s):

Estefano Machado ◽

Stefano E. Romero ◽

Gilmer Flores ◽

Benjamin Castaneda

Keyword(s):

Skeletal Muscle ◽

Shear Wave ◽

Shear Wave Elastography ◽

In Vivo Assessment

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Stiffness of the Masseter Muscle in Children—Establishing the Reference Values in the Pediatric Population Using Shear-Wave Elastography

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18189619 ◽

2021 ◽

Vol 18 (18) ◽

pp. 9619

Author(s):

Cyprian Olchowy ◽

Anna Olchowy ◽

Aleksander Pawluś ◽

Mieszko Więckiewicz ◽

Luca Maria Sconfienza

Keyword(s):

Shear Wave ◽

Masseter Muscle ◽

Pediatric Population ◽

Shear Wave Elastography ◽

Total Sample ◽

Healthy Children ◽

Significant Difference ◽

The Right ◽

The Impact ◽

Masseter Muscles

In children, the quality and muscle function are altered in many pathologic conditions, including temporomandibular disorders. Although several methods have been used to evaluate muscle tonus, none became a golden standard. Moreover, the masseter muscle characteristics in children have not been investigated to date. This study aimed to measure the stiffness of the masseter muscle using shear-wave elastography in healthy children. We enrolled 30 healthy children (mean age 10.87 ± 3.38 years). The stiffness of masseter muscles was measured with shear wave elastography. Stiffness for the total sample was 6.37 ± 0.77 kPa. A comparison of the measurements did not show significant differences between the right and the left masseter muscles (left—6.47 ± 0.78 kPa; right—6.24 ± 0.76 kPa; p = 0.3546). A significant difference was seen between boys and girls (boys—5.94 ± 0.50 kPa; girls—6.63 ± 0.80; p = 0.0006). Shear-wave elastography is a promising diagnostic tool. It may help to detect changes in the stiffness of the masseter muscle and draw attention to pathological processes within the jaw muscles. Directions for further research shall include determining stiffness values in pathological conditions and the impact of biological and functional factors on the stiffness of the masseter muscle.

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Effect of Rest Duration Between Static Stretching on Passive Stiffness of Medial Gastrocnemius Muscle In Vivo

Journal of Sport Rehabilitation ◽

10.1123/jsr.2018-0376 ◽

2020 ◽

Vol 29 (5) ◽

pp. 578-582

Author(s):

Masatoshi Nakamura ◽

Shigeru Sato ◽

Ryosuke Kiyono ◽

Nobushige Takahashi ◽

Tomoichi Yoshida

Keyword(s):

Elastic Modulus ◽

Shear Wave ◽

Repeated Measures ◽

Shear Wave Elastography ◽

Muscle Stiffness ◽

Medial Gastrocnemius ◽

Static Stretching ◽

Shear Elastic Modulus ◽

Before And After

Context: In clinical and sports settings, static stretching (SS) is usually performed to increase range of motion (ROM) and decrease passive muscle stiffness. Recently, the shear elastic modulus was measured by ultrasonic shear wave elastography as an index of muscle stiffness. Previous studies reported that the shear elastic modulus measured by ultrasound shear wave elastography decreased after SS, and the effects of SS on shear elastic modulus were likely affected by rest duration between sets of SS. Objective: To investigate the acute effects of SS with different rest durations on ROM and shear elastic modulus of gastrocnemius and to clarify whether the rest duration between sets of SS decreases the shear elastic modulus. Design: A randomized, repeated-measures experimental design. Setting: University laboratory. Participants: Sixteen healthy males volunteered to participate in the study (age 21.3 [0.8] y; height 171.8 [5.1] cm; weight 63.1 [4.5] kg). Main Outcome Measures: Each participant underwent 3 different rest interval durations during SS (ie, long rest duration: 90 s; normal rest duration: 30 s; and short rest duration: 10 s). This SS technique was repeated 10 times, thus lasting a total of 300 seconds with different rest durations in each protocol. The dorsiflexion ROM and shear elastic modulus were measured before and after SS. Results: Our results revealed that dorsiflexion ROM and shear elastic modulus were changed after 300-second SS; however, no effects of the rest duration between sets of SS were observed. Conclusions: In terms of decreasing the shear elastic modulus, clinicians and coaches should not focus on the rest duration when SS intervention is performed.

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