Background
Methods
Participants
Clinical examination
Ultrasound image recording
Device and settings
Ultrasonographers
Image recording protocol
Image analysis
QUS measurements computed from a grayscale histogram | Mathematical formulas | |
First order statistics | ||
Echogenicity Mean (\( \overline{\mathrm{x}} \)) | Mean of grayscale values of micro pixels encompassed within the ROI (from 0 (black) to 255 (white) inclusively). |
\( \overline{\mathrm{x}} = {\displaystyle {\sum}_{\mathrm{x}=1}^{\mathrm{M}}}{\displaystyle {\sum}_{\mathrm{y}=1}^{\mathrm{N}}}\frac{\mathrm{I}\left(\mathrm{x},\mathrm{y}\right)}{\mathrm{M}\mathrm{N}} \)
|
Variance (σ2) | Dispersion around the mean of the grayscale values of micro pixels encompassed within the ROI. |
\( {\upsigma}^2=\frac{{\displaystyle {\sum}_{\mathrm{X}=1}^{\mathrm{M}}}{\displaystyle {\sum}_{\mathrm{y}-1}^{\mathrm{N}}}{\left\{\mathrm{I}\left(\mathrm{x},\mathrm{y}\right)-\overline{\mathrm{x}}\right\}}^2}{\mathrm{M}\mathrm{N}} \)
|
Skewness (Sk) | Reflects the asymmetry of the grey level frequency distribution curve around its mean. A high coefficient (in absolute value) translates in a shifted distribution relative to the mean, while a zero coefficient indicates a symmetric distribution. In a positively skewed distribution, pixels intensities are biased toward lower values (shifted distribution to the left). In a negatively skewed distribution, pixels intensities are biased toward higher values (shifted distribution to the right). |
\( {\mathrm{S}}_{\mathrm{k}}=\frac{1}{\mathrm{M}\mathrm{N}}\frac{{\displaystyle {\sum}_{\mathrm{x}=1}^{\mathrm{M}}}{\displaystyle {\sum}_{\mathrm{y}=1}^{\mathrm{N}}}{\left\{\mathrm{I}\left(\mathrm{x},\mathrm{y}\right)-\overline{\mathrm{x}}\right\}}^3}{\upsigma^3} \)
|
Kurtosis (Kt) | Reflects the flatness of the grey level frequency distribution curve around its mean. A diffuse distribution will translate in a lower kurtosis value. Distribution concentrated around its mean will translate in a higher kurtosis value. |
\( {\mathrm{K}}_{\mathrm{t}}=\frac{1}{\mathrm{M}\mathrm{N}}\frac{{\displaystyle {\sum}_{\mathrm{x}=1}^{\mathrm{M}}}{\displaystyle {\sum}_{\mathrm{y}=1}^{\mathrm{N}}}{\left\{\mathrm{I}\left(\mathrm{x},\mathrm{y}\right)-\overline{\mathrm{x}}\right\}}^4}{\upsigma^4} \)
|
Entropy (E) | Reflects disorder in a ROI. It considers the number of grey levels in a ROI, and the proportions of each grey level. There is an increased entropy when multiple grey level values are present in the ROI. Vice-versa, entropy equals zero if an image has a single grey level value for all its micro pixels. |
\( \mathrm{E}=-{\displaystyle {\sum}_{\mathrm{i}=0}^{255}}{\displaystyle {\sum}_{\mathrm{j}=0}^{255}}\mathrm{p}\left(\mathrm{i},\mathrm{j}\right){ \log}_2\left(\mathrm{p}\left(\mathrm{i},\mathrm{j}\right)\right) \)
|
QUS Measurements computed from a co-occurence matrix | ||
Texture parameters | ||
Contrast (I
con
) | Contrast measures the difference of intensity between the grey level values of neighboring micro pixels. There is a reduced contrast in a constant image with lesser local variations of the grey level intensities. On the contrary, contrast is higher in an image containing a large amount of local sudden variations in the values of grey level intensities. |
\( {\mathrm{I}}_{\mathrm{con}}={\displaystyle {\sum}_{\mathrm{i}=0}^{255}}{\displaystyle {\sum}_{\mathrm{j}=1}^{255}}{\left|\mathrm{i}-\mathrm{j}\right|}^2\ \mathrm{p}\left(\mathrm{i},\mathrm{j}\right) \)
|
Energy (I
eng
) | Energy is linked to the regularity and consistency of the patterns in an image. High energy is measured in a constant and steady picture. Vice-versa, low energy is found in an image in which the contacts of grey level values are diverse, uncoordinated and random. |
\( {\mathrm{I}}_{\mathrm{eng}}={\displaystyle {\sum}_{\mathrm{i}=0}^{255}}{\displaystyle {\sum}_{\mathrm{j}=0}^{255}}\mathrm{p}{\left(\mathrm{i},\mathrm{j}\right)}^2 \)
|
Homogeneity (I
hmg
) | Homogeneity is increased in an image with a large number of pixels having the same grey level values, with little grayscale transition (i.e., increased when there is a large area of the same color). |
\( {\mathrm{I}}_{\mathrm{hmg}}={\displaystyle {\sum}_{\mathrm{i}=0}^{255}}{\displaystyle {\sum}_{\mathrm{j}=0}^{255}}\frac{1}{1+{\left(\mathrm{i}-\mathrm{j}\right)}^2}\mathrm{p}\left(\mathrm{i},\mathrm{j}\right) \)
|
Statistical analysis
Outcome measures
Reliability
Standard error of measurement
Minimal detectable change
Results
Outcome measures (QUS Measurements) | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
All tendons n = 86 | Symptomatic n = 23 | Asymptomatic n = 63 | Difference between groups (%) | |||||||
Average | Stand. Dev. | 95 % CIa | Average | Stand. Dev. | 95 % CIa | Average | Stand. Dev. | 95 % CIa | ||
Longitudinal view | ||||||||||
Geometric | ||||||||||
Thickness (cm) | 0.56 | 0.16 | 0.53–0.59 | 0.68 | 0.21 | 0.60–0.76 | 0.52 | 0.10 | 0.49–0.54 | 31.88 |
Grayscale histogram | ||||||||||
Echogenicity (0–255) | 82.37 | 14.44 | 79.31–85.42 | 79.32 | 14.22 | 73.51–85.13 | 83.48 | 13.32 | 80.19–86.77 | −4.98 |
Variance | 618.72 | 216.98 | 572.86–664.58 | 654.93 | 213.52 | 567.66–742.19 | 605.50 | 160.62 | 565.83–645.16 | 8.16 |
Skewness | 0.52 | 0.34 | 0.45–0.59 | 0.65 | 0.25 | 0.55–0.75 | 0.47 | 0.21 | 0.42–0.53 | 38.13 |
Kurtosis | 3.82 | 1.28 | 3.54–4.09 | 4.18 | 1.02 | 3.76–4.59 | 3.68 | 0.64 | 3.52–3.84 | 13.41 |
Entropy | 6.50 | 0.24 | 6.45–6.55 | 6.51 | 0.24 | 6.41–6.61 | 6.50 | 0.19 | 6.46–6.55 | 0.10 |
Co –occurrence matrix | ||||||||||
Contrast | 0.64 | 0.13 | 0.61–0.67 | 0.61 | 0.11 | 0.57–0.66 | 0.65 | 0.11 | 0.62–0.68 | −5.67 |
Energy | 0.21 | 0.05 | 0.20–0.22 | 0.21 | 0.04 | 0.19–0.22 | 0.21 | 0.04 | 0.20–0.22 | −2.76 |
Homogeneity | 0.76 | 0.03 | 0.76–0.77 | 0.77 | 0.02 | 0.76–0.77 | 0.76 | 0.02 | 0.75–0.77 | 0.82 |
Transverse view | ||||||||||
Geometric | ||||||||||
Area (CSA) (cm2) | 0.61 | 0.23 | 0.56–0.66 | 0.76 | 0.33 | 0.63–0.90 | 0.56 | 0.14 | 0.52–0.59 | 36.61 |
Thickness (cm) | 0.57 | 0.15 | 0.54–0.60 | 0.67 | 0.20 | 0.59–0.75 | 0.53 | 0.09 | 0.51–0.55 | 26.73 |
Width (cm) | 1.32 | 0.16 | 1.28–1.35 | 1.37 | 0.19 | 1.29–1.44 | 1.30 | 0.13 | 1.27–1.33 | 5.30 |
Grayscale histogram | ||||||||||
Echogenicity (0–255) | 90.98 | 13.42 | 88.14–93.81 | 86.62 | 14.85 | 80.55–92.68 | 92.57 | 10.97 | 89.86–95.28 | −6.43 |
Variance | 767.57 | 207.20 | 723.77–811.36 | 789.63 | 180.44 | 715.88–863.37 | 759.51 | 150.15 | 722.44–796.59 | 3.96 |
Skewness | 0.54 | 0.25 | 0.49–0.60 | 0.63 | 0.20 | 0.55–0.71 | 0.51 | 0.20 | 0.46–0.56 | 24.15 |
Kurtosis | 3.61 | 0.83 | 3.43–3.78 | 3.78 | 0.75 | 3.48–4.09 | 3.55 | 0.58 | 3.40–3.69 | 6.68 |
Entropy | 6.74 | 0.15 | 6.71–6.77 | 6.73 | 0.11 | 6.68–6.78 | 6.74 | 0.12 | 6.71–6.77 | −0.15 |
Co-occurrence matrix | ||||||||||
Contrast | 0.90 | 0.16 | 0.86–0.93 | 0.84 | 0.16 | 0.78–0.91 | 0.92 | 0.13 | 0.89–0.95 | −8.33 |
Energy | 0.14 | 0.04 | 0.13–0.15 | 0.15 | 0.03 | 0.13–0.16 | 0.14 | 0.03 | 0.13–0.14 | 5.76 |
Homogeneity | 0.73 | 0.03 | 0.72–0.73 | 0.74 | 0.03 | 0.72–0.75 | 0.72 | 0.02 | 0.72–0.73 | 1.95 |
Sources of variance
QUS measurements | Relative variance proportions for images recorded in longitudinal view (%) | ||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
S | E | V | I | SE | SV | SI | EV | EI | VI | SEV | SEI | SVI | EVI | SEVI | |
Geometric | |||||||||||||||
Thickness | |||||||||||||||
Sympt | 83.0 | 2.2 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 1.0 | 0.0 | 0.0 | 6.2 | 4.0 | 1.7 | 0.0 | 1.9 |
Asympt | 86.2 | 0.8 | 0.0 | 0.0 | 2.8 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 3.3 | 1.4 | 0.8 | 0.0 | 4.8 |
Grayscale histogram | |||||||||||||||
Echogenicity | |||||||||||||||
Sympt | 75.7 | 0.0 | 0.0 | 0.0 | 7.7 | 0.0 | 0.0 | 0.0 | 0.0 | 0.1 | 8.8 | 1.2 | 0.5 | 0.0 | 5.8 |
Asympt | 85.2 | 0.0 | 0.0 | 0.0 | 3.4 | 1.6 | 0.0 | 0.1 | 0.0 | 0.0 | 3.4 | 0.0 | 0.0 | 0.0 | 6.2 |
Variance | |||||||||||||||
Sympt | 35.1 | 1.1 | 0.0 | 0.0 | 32.9 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 12.2 | 0.0 | 0.0 | 0.0 | 18.7 |
Asympt | 61.7 | 0.0 | 0.1 | 0.0 | 1.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 8.7 | 0.0 | 1.3 | 0.0 | 27.3 |
Skewness | |||||||||||||||
Sympt | 21.8 | 13.2 | 0.0 | 1.9 | 15.0 | 0.0 | 0.0 | 0.2 | 0.3 | 1.8 | 0.0 | 0.0 | 7.4 | 0.0 | 38.5 |
Asympt | 26.8 | 7.6 | 0.0 | 0.0 | 12.7 | 0.0 | 0.0 | 0.0 | 0.4 | 0.1 | 7.3 | 11.0 | 3.9 | 0.0 | 30.2 |
Kurtosis | |||||||||||||||
Sympt | 10.9 | 5.8 | 0.0 | 0.0 | 17.4 | 0.0 | 0.0 | 0.0 | 0.2 | 2.0 | 11.0 | 0.0 | 8.8 | 0.0 | 43.9 |
Asympt | 16.3 | 7.3 | 0.0 | 0.0 | 19.1 | 0.5 | 0.3 | 0.0 | 1.1 | 0.0 | 9.3 | 13.4 | 1.9 | 0.0 | 30.8 |
Entropy | |||||||||||||||
Sympt | 44.0 | 0.0 | 0.0 | 0.0 | 26.3 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 16.4 | 1.6 | 2.1 | 0.0 | 9.6 |
Asympt | 58.8 | 0.2 | 0.2 | 0.0 | 5.7 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 10.2 | 0.0 | 5.5 | 0.0 | 19.5 |
Co-occurrence matrix | |||||||||||||||
Contrast | |||||||||||||||
Sympt | 55.3 | 0.0 | 0.0 | 0.0 | 8.1 | 0.0 | 0.0 | 0.4 | 0.5 | 0.0 | 12.8 | 7.0 | 6.1 | 0.0 | 10.0 |
Asympt | 61.3 | 0.0 | 0.0 | 0.0 | 4.5 | 0.8 | 0.0 | 0.9 | 0.0 | 0.2 | 5.1 | 0.0 | 4.2 | 0.0 | 22.9 |
Energy | |||||||||||||||
Sympt | 40.9 | 0.0 | 0.0 | 0.4 | 19.6 | 0.0 | 0.4 | 0.0 | 0.0 | 0.0 | 17.8 | 0.9 | 0.0 | 0.0 | 20.0 |
Asympt | 55.3 | 0.0 | 0.0 | 0.0 | 9.2 | 0.4 | 0.0 | 0.7 | 0.0 | 0.0 | 8.1 | 0.0 | 4.4 | 0.0 | 22.0 |
Homogeneity | |||||||||||||||
Sympt | 56.3 | 0.0 | 0.0 | 0.0 | 6.3 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 12.5 | 4.7 | 7.8 | 0.0 | 12.5 |
Asympt | 63.9 | 0.0 | 0.0 | 0.0 | 6.9 | 1.4 | 0.0 | 1.4 | 0.0 | 0.0 | 4.2 | 0.0 | 4.2 | 0.0 | 18.1 |
QUS measurements | Relative variance proportions for images recorded in transverse view (%) | ||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
S | E | V | I | SE | SV | SI | EV | EI | VI | SEV | SEI | SVI | EVI | SEVI | |
Geometric | |||||||||||||||
Area (CSA) | |||||||||||||||
Sympt | 92.8 | 0.0 | 0.0 | 0.0 | 3.0 | 0.1 | 0.2 | 0.0 | 0.0 | 0.1 | 0.9 | 0.0 | 0.4 | 0.0 | 2.4 |
Asympt | 86.8 | 0.0 | 0.0 | 0.0 | 3.9 | 0.0 | 0.1 | 0.0 | 0.0 | 0.0 | 1.6 | 1.3 | 0.0 | 0.1 | 6.3 |
Thickness | |||||||||||||||
Sympt | 92.6 | 0.0 | 0.0 | 0.0 | 3.3 | 0.2 | 0.1 | 0.0 | 0.0 | 0.0 | 1.9 | 0.4 | 0.0 | 0.1 | 1.5 |
Asympt | 74.5 | 0.0 | 0.0 | 0.0 | 8.7 | 0.2 | 0.0 | 0.0 | 0.0 | 0.0 | 2.1 | 3.9 | 0.0 | 0.0 | 10.5 |
Width | |||||||||||||||
Sympt | 80.4 | 0.0 | 0.0 | 0.0 | 2.0 | 0.0 | 0.2 | 0.0 | 0.0 | 0.4 | 2.1 | 0.0 | 0.0 | 0.0 | 15.0 |
Asympt | 71.0 | 2.3 | 0.1 | 0.0 | 7.3 | 0.0 | 0.0 | 0.0 | 0.1 | 0.0 | 6.8 | 1.6 | 1.6 | 0.1 | 9.2 |
Grayscale histogram | |||||||||||||||
Echogenicity | |||||||||||||||
Sympt | 81.3 | 4.4 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.1 | 6.1 | 1.5 | 1.5 | 0.4 | 4.6 |
Asympt | 73.2 | 5.0 | 0.0 | 0.0 | 4.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 2.3 | 0.0 | 1.6 | 0.0 | 13.9 |
Variance | |||||||||||||||
Sympt | 31.2 | 13.7 | 0.0 | 0.0 | 9.4 | 0.0 | 0.0 | 0.0 | 0.1 | 0.8 | 26.3 | 5.1 | 4.5 | 0.2 | 8.6 |
Asympt | 49.9 | 10.1 | 0.0 | 0.0 | 6.7 | 1.4 | 0.0 | 0.0 | 0.0 | 0.0 | 10.7 | 2.8 | 2.0 | 0.0 | 16.5 |
Skewness | |||||||||||||||
Sympt | 42.9 | 7.5 | 0.0 | 0.0 | 1.0 | 7.2 | 0.0 | 0.0 | 0.0 | 0.0 | 2.2 | 0.0 | 0.0 | 0.0 | 39.2 |
Asympt | 58.9 | 0.0 | 0.0 | 0.0 | 0.8 | 1.0 | 0.1 | 0.0 | 0.2 | 0.0 | 9.0 | 7.0 | 0.0 | 0.3 | 22.7 |
Kurtosis | |||||||||||||||
Sympt | 37.8 | 0.3 | 0.5 | 0.0 | 0.0 | 6.7 | 0.0 | 0.0 | 0.3 | 0.0 | 13.5 | 6.9 | 0.0 | 0.0 | 34.1 |
Asympt | 44.6 | 0.7 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 11.8 | 16.3 | 4.7 | 0.8 | 21.1 |
Entropy | |||||||||||||||
Sympt | 25.8 | 4.3 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.7 | 2.1 | 40.0 | 5.9 | 10.8 | 0.0 | 10.5 |
Asympt | 48.8 | 3.6 | 0.0 | 0.0 | 12.3 | 4.2 | 3.6 | 0.0 | 0.2 | 0.2 | 5.7 | 1.8 | 0.0 | 0.0 | 19.5 |
Co-occurrence matrix | |||||||||||||||
Contrast | |||||||||||||||
Sympt | 73.8 | 6.8 | 0.0 | 0.0 | 1.3 | 0.0 | 1.4 | 0.0 | 0.0 | 0.0 | 8.3 | 0.1 | 0.0 | 0.4 | 7.8 |
Asympt | 59.6 | 2.2 | 0.0 | 0.6 | 4.0 | 3.0 | 0.0 | 0.0 | 0.0 | 0.6 | 5.2 | 3.3 | 2.5 | 0.0 | 19.0 |
Energy | |||||||||||||||
Sympt | 58.2 | 5.5 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 1.2 | 21.8 | 3.0 | 2.4 | 0.6 | 7.3 |
Asympt | 68.9 | 4.9 | 0.0 | 0.0 | 4.9 | 2.5 | 0.8 | 0.0 | 0.0 | 0.0 | 3.3 | 0.0 | 0.0 | 0.0 | 14.8 |
Homogeneity | |||||||||||||||
Sympt | 80.8 | 6.1 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 4.0 | 0.0 | 0.0 | 1.0 | 8.1 |
Asympt | 67.2 | 4.9 | 0.0 | 0.0 | 4.9 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 1.6 | 1.6 | 1.6 | 0.0 | 18.0 |
Reliability and minimal detectable change
QUS measurements in longitudinal view | E = 1 | |||||||
---|---|---|---|---|---|---|---|---|
V = 1 | V = 2 | |||||||
I = 1 | I = 2 | I = 3 | I = 1 | I = 2 | I = 3 | |||
Geometric | ||||||||
Thickness | SYMPT | Φ | 0.85 | 0.88 | 0.90 | 0.90 | 0.93 | 0.94 |
SEM | 0.09 | 0.07 | 0.07 | 0.07 | 0.06 | 0.05 | ||
MDC90%NORM | 29.21 | 25.17 | 23.66 | 23.28 | 19.35 | 17.84 | ||
ASYMPT | Φ | 0.90 | 0.93 | 0.94 | 0.94 | 0.96 | 0.97 | |
SEM | 0.03 | 0.03 | 0.02 | 0.02 | 0.02 | 0.02 | ||
MDC90%NORM | 14.52 | 11.80 | 10.74 | 10.94 | 8.76 | 7.90 | ||
Grayscale histogram | ||||||||
Echogenicity | SYMPT | Φ | 0.83 | 0.87 | 0.88 | 0.90 | 0.93 | 0.93 |
SEM | 6.35 | 5.56 | 5.27 | 4.65 | 4.03 | 3.79 | ||
MDC90%NORM | 18.68 | 16.36 | 15.51 | 13.69 | 11.84 | 11.16 | ||
ASYMPT | Φ | 0.89 | 0.91 | 0.92 | 0.94 | 0.96 | 0.96 | |
SEM | 4.76 | 4.05 | 3.78 | 3.37 | 2.87 | 2.68 | ||
MDC90%NORM | 13.31 | 11.32 | 10.57 | 9.43 | 8.01 | 7.48 | ||
Variance | SYMPT | Φ | 0.69 | 0.76 | 0.79 | 0.81 | 0.86 | 0.88 |
SEM | 157.27 | 131.36 | 121.51 | 111.20 | 92.89 | 85.92 | ||
MDC90%NORM | 56.03 | 46.80 | 43.29 | 39.62 | 33.09 | 30.61 | ||
ASYMPT | Φ | 0.63 | 0.73 | 0.77 | 0.77 | 0.84 | 0.87 | |
SEM | 118.97 | 93.45 | 83.22 | 84.12 | 66.08 | 58.85 | ||
MDC90%NORM | 45.85 | 36.01 | 32.07 | 32.42 | 25.47 | 22.68 | ||
Skewness | SYMPT | Φ | 0.42 | 0.59 | 0.69 | 0.58 | 0.74 | 0.81 |
SEM | 0.29 | 0.21 | 0.17 | 0.21 | 0.15 | 0.12 | ||
MDC90%NORM | 104.67 | 74.18 | 60.70 | 75.60 | 53.58 | 43.84 | ||
ASYMPT | Φ | 0.43 | 0.57 | 0.64 | 0.55 | 0.69 | 0.75 | |
SEM | 0.24 | 0.18 | 0.15 | 0.18 | 0.14 | 0.12 | ||
MDC90%NORM | 116.65 | 87.95 | 76.02 | 90.96 | 67.84 | 58.13 | ||
Kurtosis | SYMPT | Φ | 0.30 | 0.42 | 0.49 | 0.46 | 0.59 | 0.66 |
SEM | 1.50 | 1.15 | 1.00 | 1.06 | 0.81 | 0.71 | ||
MDC90%NORM | 83.94 | 64.13 | 55.99 | 59.44 | 45.40 | 39.63 | ||
ASYMPT | Φ | 0.38 | 0.51 | 0.58 | 0.50 | 0.63 | 0.70 | |
SEM | 0.81 | 0.62 | 0.54 | 0.64 | 0.48 | 0.42 | ||
MDC90%NORM | 51.31 | 39.27 | 34.34 | 40.69 | 30.67 | 26.51 | ||
Entropy | SYMPT | Φ | 0.70 | 0.75 | 0.77 | 0.82 | 0.85 | 0.87 |
SEM | 0.17 | 0.15 | 0.14 | 0.12 | 0.10 | 0.10 | ||
MDC90%NORM | 5.92 | 5.21 | 4.95 | 4.30 | 3.75 | 3.55 | ||
ASYMPT | Φ | 0.65 | 0.74 | 0.77 | 0.78 | 0.85 | 0.87 | |
SEM | 0.13 | 0.11 | 0.10 | 0.09 | 0.08 | 0.07 | ||
MDC90%NORM | 4.79 | 3.85 | 3.48 | 3.39 | 2.72 | 2.46 | ||
Co-occurrence matrix | ||||||||
Contrast | SYMPT | Φ | 0.63 | 0.72 | 0.75 | 0.74 | 0.82 | 0.84 |
SEM | 0.08 | 0.07 | 0.06 | 0.06 | 0.05 | 0.05 | ||
MDC90%NORM | 30.57 | 25.20 | 23.14 | 23.72 | 19.11 | 17.30 | ||
ASYMPT | Φ | 0.66 | 0.76 | 0.80 | 0.79 | 0.87 | 0.89 | |
SEM | 0.08 | 0.06 | 0.05 | 0.06 | 0.04 | 0.04 | ||
MDC90%NORM | 28.23 | 21.88 | 19.30 | 19.96 | 15.47 | 13.65 | ||
Energy | SYMPT | Φ | 0.60 | 0.68 | 0.71 | 0.75 | 0.80 | 0.83 |
SEM | 0.03 | 0.03 | 0.02 | 0.02 | 0.02 | 0.02 | ||
MDC90%NORM | 33.74 | 28.73 | 26.85 | 24.39 | 20.63 | 19.21 | ||
ASYMPT | Φ | 0.64 | 0.74 | 0.78 | 0.78 | 0.85 | 0.88 | |
SEM | 0.03 | 0.02 | 0.02 | 0.02 | 0.02 | 0.02 | ||
MDC90%NORM | 34.26 | 27.17 | 24.35 | 24.22 | 19.21 | 17.22 | ||
Homogeneity | SYMPT | Φ | 0.63 | 0.71 | 0.75 | 0.75 | 0.82 | 0.85 |
SEM | 0.02 | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 | ||
MDC90%NORM | 4.72 | 3.85 | 3.52 | 3.54 | 2.85 | 2.58 | ||
ASYMPT | Φ | 0.71 | 0.80 | 0.83 | 0.83 | 0.89 | 0.91 | |
SEM | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 | ||
MDC90%NORM | 4.45 | 3.50 | 3.12 | 3.15 | 2.48 | 2.21 |
QUS measurements in transverse view | E = 1 | |||||||
---|---|---|---|---|---|---|---|---|
V = 1 | V = 2 | |||||||
I = 1 | I = 2 | I = 3 | I = 1 | I = 2 | I = 3 | |||
Geometric | ||||||||
Area (CSA) | SYMPT | Φ | 0.96 | 0.97 | 0.98 | 0.98 | 0.99 | 0.99 |
SEM | 0.07 | 0.05 | 0.05 | 0.05 | 0.04 | 0.03 | ||
MDC90%NORM | 20.91 | 16.58 | 14.85 | 15.18 | 11.97 | 10.69 | ||
ASYMPT | Φ | 0.91 | 0.94 | 0.96 | 0.94 | 0.97 | 0.98 | |
SEM | 0.05 | 0.03 | 0.03 | 0.03 | 0.03 | 0.02 | ||
MDC90%NORM | 18.96 | 14.50 | 12.67 | 14.38 | 10.89 | 9.45 | ||
Thickness | SYMPT | Φ | 0.96 | 0.97 | 0.97 | 0.98 | 0.98 | 0.99 |
SEM | 0.04 | 0.04 | 0.03 | 0.03 | 0.03 | 0.03 | ||
MDC90%NORM | 14.79 | 12.85 | 12.13 | 11.02 | 9.41 | 8.81 | ||
ASYMPT | Φ | 0.83 | 0.90 | 0.92 | 0.89 | 0.94 | 0.95 | |
SEM | 0.04 | 0.03 | 0.03 | 0.03 | 0.02 | 0.02 | ||
MDC90%NORM | 17.46 | 13.18 | 11.41 | 13.72 | 10.24 | 8.78 | ||
Width | SYMPT | Φ | 0.82 | 0.89 | 0.92 | 0.90 | 0.94 | 0.96 |
SEM | 0.09 | 0.06 | 0.06 | 0.06 | 0.05 | 0.04 | ||
MDC90%NORM | 14.69 | 10.98 | 9.42 | 10.44 | 7.80 | 6.69 | ||
ASYMPT | Φ | 0.80 | 0.86 | 0.88 | 0.88 | 0.92 | 0.93 | |
SEM | 0.06 | 0.05 | 0.05 | 0.05 | 0.04 | 0.04 | ||
MDC90%NORM | 11.61 | 9.55 | 8.75 | 8.56 | 6.97 | 6.35 | ||
Grayscale histogram | ||||||||
Echogenicity | SYMPT | Φ | 0.85 | 0.89 | 0.90 | 0.91 | 0.94 | 0.95 |
SEM | 6.11 | 5.16 | 4.81 | 4.55 | 3.79 | 3.50 | ||
MDC90%NORM | 16.47 | 13.91 | 12.95 | 12.25 | 10.20 | 9.42 | ||
ASYMPT | Φ | 0.81 | 0.88 | 0.91 | 0.90 | 0.94 | 0.95 | |
SEM | 5.25 | 3.94 | 3.39 | 3.71 | 2.79 | 2.40 | ||
MDC90%NORM | 13.23 | 9.93 | 8.56 | 9.35 | 7.02 | 6.05 | ||
Variance | SYMPT | Φ | 0.47 | 0.53 | 0.55 | 0.61 | 0.68 | 0.70 |
SEM | 179.83 | 159.58 | 152.23 | 134.27 | 116.89 | 110.49 | ||
MDC90%NORM | 53.14 | 47.16 | 44.99 | 39.68 | 34.54 | 32.65 | ||
ASYMPT | Φ | 0.63 | 0.71 | 0.75 | 0.76 | 0.82 | 0.85 | |
SEM | 112.00 | 92.43 | 84.91 | 82.42 | 67.32 | 61.47 | ||
MDC90%NORM | 34.41 | 28.40 | 26.09 | 25.32 | 20.68 | 18.89 | ||
Skewness | SYMPT | Φ | 0.47 | 0.60 | 0.66 | 0.64 | 0.75 | 0.80 |
SEM | 0.19 | 0.15 | 0.13 | 0.13 | 0.10 | 0.09 | ||
MDC90%NORM | 69.88 | 53.98 | 47.51 | 49.41 | 38.17 | 33.59 | ||
ASYMPT | Φ | 0.60 | 0.70 | 0.75 | 0.72 | 0.81 | 0.84 | |
SEM | 0.15 | 0.12 | 0.11 | 0.12 | 0.09 | 0.08 | ||
MDC90%NORM | 69.85 | 55.19 | 49.35 | 53.67 | 41.75 | 36.94 | ||
Kurtosis | SYMPT | Φ | 0.38 | 0.48 | 0.52 | 0.52 | 0.63 | 0.67 |
SEM | 0.83 | 0.68 | 0.62 | 0.62 | 0.50 | 0.45 | ||
MDC90%NORM | 51.01 | 41.66 | 38.04 | 38.09 | 30.71 | 27.81 | ||
ASYMPT | Φ | 0.45 | 0.57 | 0.63 | 0.56 | 0.68 | 0.74 | |
SEM | 0.58 | 0.45 | 0.40 | 0.47 | 0.36 | 0.31 | ||
MDC90%NORM | 38.08 | 29.68 | 26.29 | 30.68 | 23.42 | 20.44 | ||
Entropy | SYMPT | Φ | 0.27 | 0.32 | 0.34 | 0.40 | 0.47 | 0.50 |
SEM | 0.15 | 0.13 | 0.13 | 0.11 | 0.10 | 0.09 | ||
MDC90%NORM | 5.17 | 4.58 | 4.37 | 3.82 | 3.34 | 3.16 | ||
ASYMPT | Φ | 0.63 | 0.73 | 0.77 | 0.75 | 0.83 | 0.86 | |
SEM | 0.09 | 0.07 | 0.06 | 0.07 | 0.05 | 0.05 | ||
MDC90%NORM | 3.02 | 2.42 | 2.18 | 2.30 | 1.81 | 1.62 | ||
Co-occurrence matrix | ||||||||
Contrast | SYMPT | Φ | 0.81 | 0.85 | 0.87 | 0.88 | 0.92 | 0.93 |
SEM | 0.08 | 0.07 | 0.06 | 0.06 | 0.05 | 0.04 | ||
MDC90%NORM | 21.25 | 18.16 | 17.01 | 15.64 | 13.20 | 12.29 | ||
ASYMPT | Φ | 0.65 | 0.75 | 0.79 | 0.77 | 0.85 | 0.88 | |
SEM | 0.09 | 0.07 | 0.06 | 0.07 | 0.05 | 0.05 | ||
MDC90%NORM | 22.63 | 17.82 | 15.90 | 16.89 | 13.17 | 11.67 | ||
Energy | SYMPT | Φ | 0.62 | 0.67 | 0.69 | 0.75 | 0.79 | 0.81 |
SEM | 0.02 | 0.02 | 0.02 | 0.02 | 0.02 | 0.02 | ||
MDC90%NORM | 39.31 | 35.16 | 33.67 | 28.93 | 25.50 | 24.25 | ||
ASYMPT | Φ | 0.78 | 0.85 | 0.87 | 0.87 | 0.91 | 0.93 | |
SEM | 0.02 | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 | ||
MDC90%NORM | 27.37 | 21.80 | 19.60 | 19.72 | 15.65 | 14.03 | ||
Homogeneity | SYMPT | Φ | 0.86 | 0.90 | 0.92 | 0.92 | 0.95 | 0.96 |
SEM | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 | ||
MDC90%NORM | 3.61 | 2.92 | 2.65 | 2.55 | 2.07 | 1.87 | ||
ASYMPT | Φ | 0.76 | 0.85 | 0.89 | 0.85 | 0.92 | 0.94 | |
SEM | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 | ||
MDC90%NORM | 3.82 | 2.80 | 2.36 | 2.80 | 2.04 | 1.72 |