Real-time Tissue Elastography Research Articles

Evaluation of Lymph Nodal Staging and Stiffness of Gastrointestinal Cancers by Intraoperative Ultrasound Elastography

Introduction: Real-time tissue elastography is a new non-invasive method in ultrasonography that differentiates tissues according to their stiffness. The aim of this study was to define the diagnostic value of the intraoperative ultrasound elastography for the differentiation of benign and metastatic regional lymph nodes (LNs) in patients with gastrointestinal (GI) cancers by comparing this technique with the enhanced CT scan, intraoperative palpation by surgeons, and final pathological findings. Furthermore, we examined the factors which prescribed hardness in GI cancers. Methods: Between 2014 and 2016, a total of 70 patients with resectable GI cancer (28 gastric cancers, 42 colon cancers) who underwent operations were enrolled in this study. The LN metastases judged by ultrasound elastography, CT scans, and intraoperative palpation by surgeons were compared with the postoperative pathological results. Stiffness of tumors evaluated by elastography was compared with various pathological findings. Results: A total of 33 (47%) cancers showed LN metastasis. With a cut-off value of 2.5 for the fat tissueto-LN strain index, the respective values for sensitivity, specificity, and overall accuracy were 97%, 85%, and 89% for intraoperative ultrasound elastography; 53%, 93%, and 74% for CT scan; and 60%, 95%, and 79% for palpation by surgeons. Sensitivity and accuracy were found to be significantly higher for intraoperative ultrasound elastography than for CT scan and intraoperative palpation. No significant differences in tumor stiffness among diseases, tumor size and stage. However, significant differences were found in stroma and histological type of tumors. Conclusion: Nodal diagnosis by intraoperative ultrasound elastography could be a reliable and accurate method in GI cancers when compared to other recent modalities. Our data imply that ultrasound elastography could be the best modality during the intraoperative nodal staging of GI cancers. The factors which prescribed stiffness of tumors were stroma, an invasive style, and a histologic type.

Changes in liver stiffness on real-time tissue elastography before and after occlusion of spontaneous portosystemic shunts.

This study was conducted to evaluate changes in liver stiffness, volume, and function before and after occlusion of spontaneous portosystemic shunt. Twenty-four patients (13 men and 11 women) with a mean age of 68.2 years±10.1 (SD) (age range, 49-82 years) underwent percutaneous occlusion of spontaneous portosystemic shunt because of gastric varices (n=17) or hepatic encephalopathy (n=7) from March 2011 to June 2013. The liver fibrosis index indicating liver stiffness was calculated by using ultrasound elastography before and after shunt occlusion. Liver volume and liver profile were also evaluated. Spontaneous portosystemic shunt occlusion was uneventfully performed in all patients. The mean liver fibrosis index was significantly decreased from 2.7±1.0 before shunt occlusion to 2.0±0.9 (P<0.001) at 1 month, 2.2±1.0 at 3 months (P=0.004), and 1.6±0.7 at 6 months (P=0.001) afterwards. A significant increase in the liver volume was observed from 1035.3±340.1mL before shunt occlusion to 1116.8±298.4mL (P=0.006) at 1 month and 1174.2±354.1mL (P<0.001) at 3 months afterwards. Significant improvement in the Child-Pugh score was also found at 1 month (6.2±1.4, P<0.001), 3 months (6.5±1.1, P=0.022), and 6 months (6.0±0.9, P=0.004) after shunt occlusion as compared with that (7.2±1.9) before. The liver stiffness decreases along with an increase in liver volume and improvement in liver function after spontaneous portosystemic shunt occlusion.

Usefulness of real-time tissue elastography for detecting the border of basal cell carcinomas.

Preoperative evaluation of tumor thickness and silhouette in basal cell carcinoma (BCC) is one of the important assessments to be done. However, evaluation is not always sufficient even utilizing sonography and magnetic resonance imaging. Recently, a new technique called real-time tissue elastography (RTE) was developed that can display the hardness of tissue as a color overlay of a sonographic image. Therefore, RTE could be used as a tool for detecting the tumor border according to differences in tissue rigidity. In the present study, the correlation between histopathological and RTE tumor thickness measurements was evaluated for BCC. Eleven BCC (six nodular, three superficial, and two adenoid or cystic) from individual patients were evaluated. Tumor silhouette and thickness were detected using conventional B-mode sonography and RTE. All lesions were surgically excised and tumor thickness was also examined histologically. In the six nodular BCC, the tumor silhouette determined by RTE showed a close correlation with the results of histopathology. Particularly, for four out of the six cases, the correlation was excellent. In addition, the mean difference in tumor thickness measurements between histology and RTE (-0.368 mm) was lower than that between histology and B-mode sonography (-0.835 mm). As for the superficial BCC, tumor thickness was too thin to evaluate. Tumor thickness measured by B-mode sonography and RTE was identical for two cases of adenoid or cystic BCC. In conclusion, RTE is useful in the preoperative assessment of tumor thickness, especially with the nodular type of BCC, and allows us to determine adequate surgical margins.

Development of a model based on biochemical, real‑time tissue elastography and ultrasound data for the staging of liver fibrosis and cirrhosis in patients with chronic hepatitis B.

The liver fibrosis index (LFI), based on real-time tissue elastography (RTE), is a method currently used to assess liver fibrosis. However, this method may not consistently distinguish between the different stages of fibrosis, which limits its accuracy. The aim of the present study was to develop novel models based on biochemical, RTE and ultrasound data for predicting significant liver fibrosis and cirrhosis. A total of 85 consecutive patients with chronic hepatitis B (CHB) were prospectively enrolled and underwent a liver biopsy and RTE. The parameters for predicting significant fibrosis and cirrhosis were determined by conducting multivariate analyses. The splenoportal index (SPI; P=0.002) and LFI (P=0.023) were confirmed as independent predictors of significant fibrosis. Using multivariate analyses for identifying parameters that predict cirrhosis, significant differences in γ-glutamyl transferase (GGT; P=0.049), SPI (P=0.002) and LFI (P=0.001) were observed. Based on these observations, the novel model LFI-SPI score (LSPS) was developed to predict the occurrence of significant liver fibrosis, with an area under receiver operating characteristic curves (AUROC) of 0.87. The diagnostic accuracy of the LSPS model was superior to that of the LFI (AUROC=0.76; P=0.0109), aspartate aminotransferase-to-platelet ratio index (APRI; AUROC=0.64; P=0.0031), fibrosis-4 index (FIB-4; AUROC= 0.67; P= 0.0044) and FibroScan (AUROC=0.68; P=0.0021) models. In addition, the LFI-SPI-GGT score (LSPGS) was developed for the purposes of predicting liver cirrhosis, demonstrating an AUROC value of 0.93. The accuracy of LSPGS was similar to that of FibroScan (AUROC=0.85; P=0.134), but was superior to LFI (AUROC= 0.81; P= 0.0113), APRI (AUROC= 0.67; P<0.0001) and FIB-4 (AUROC=0.719; P=0.0005). In conclusion, the results of the present study suggest that the use of LSPS and LSPGS may complement current methods of diagnosing significant liver fibrosis and cirrhosis in patients with CHB.

Differential diagnostic value of real-time tissue elastography and three dimensional ultrasound imaging in breast lumps

To investigate the real-time tissue elastography and 3D contrast-enhanced ultrasonography(CEUS) in breast lumps differential diagnostic value. A total of 126 patients (180 lumps) with breast mass were retrospectively analyzed from December 2012 to December 2014 in Tumor Hospital Affiliated To Xinjiang Medical University.All patients were divided into three groups by using stratified random method.Each group was detected by real-time tissue elastography, 3D CEUS and two joint inspection.Each group of 42 cases (60 lumps) was confirmed by the pathological results as gold standard.Diagnostic sensitivity, specificity and coincidence rate of different methods were compared. The benign masses of ultrasound contrast showed the punctate, linear and nodular enhancement, and the border of enhancement was smooth.The malignant tumors were mainly dominated by uneven and high enhancement. There was no statistical difference in sensitivity, specificity and coincidence rate between elastography group and 3D CEUS group (64.7% vs 73.5%, 69.2% vs 76.9%, 66.7% vs 75.0%, all P>0.05). The sensitivity, specificity and coincidence rate of two joint inspection group were higher than those of elastography group and 3D CEUS group, the differences were statistically significant (97.1%, 92.3% and 98.3% , all P<0.05). 3D CEUS combined with real-time tissue elastography is of high value in the diagnosis of breast masses.

Sonoelastographic Modalities in the Evaluation of Salivary Gland Characteristics in Sjögren's Syndrome

The purpose of this study was to investigate salivary tissue assessment with various sonoelastographic modalities (real-time tissue elastography, Virtual Touch imaging and quantification) in patients with Sjögren's syndrome as compared with an appropriate control group. The sonoelastographic modalities were evaluated in 50 patients with primary Sjögren's syndrome (pSS). Patients underwent high-resolution ultrasonography of the submandibular and parotid glands. Results of B-mode, real-time tissue elastography, Virtual Touch imaging—each graded with the appropriate scoring system—and Virtual Touch quantification were compared with those for 50 patients with sicca symptoms who did not fulfill the American–European consensus group criteria. In B-mode, 34 of 50 parotid glands in patients with pSS and 8 of 50 in the control group had abnormal findings (p < 0.001). Compared with 9 of 50 control patients, 38 of 50 patients with pSS had abnormal findings in submandibular gland B-mode (p < 0.001). With real-time tissue elastography, there was a trend toward higher scores for parotid glands in the pSS group (p = 0.238), whereas scores for submandibular glands in the control group were higher (p = 0.107). Virtual Touch imaging did not indicate any difference (p = 0.647 and p = 0.658). In Virtual Touch quantification, values for parotid (mean: 2.99 m/s) and submandibular glands (mean: 2.54 m/s) in the pSS group were higher than those for parotid (mean: 2.16 m/s) and submandibular (mean: 2.04 m/s) glands in the control group (p < 0.001 and p = 0.008). Glandular stiffness, measured by Virtual Touch quantification, was significantly higher in patients with Sjögreńs syndrome than in patients with sicca symptoms.

Preliminary assessment of using endorectal ultrasound and real-time elastography in the staging of advanced rectal cancer in elderly patients

Objective To evaluate the value of endorectal ultrasound(ERUS)combined with real-time elastography in the staging of advanced rectal cancer in elderly patients. Methods A total of 50 patients with advanced rectal cancer underwent endorectal ultrasound and real-time tissue elastography imaging at our hospital from Jun. 2014 to Oct. 2015. Their staging results were compared with postoperative pathology. Results The accuracy, sensitivity and specificity of ERUS in the staging of advanced rectal cancer(T3)were 90%(45/50), 93.5%(43/46)and 50%(2/4), respectively. The accuracy, sensitivity and specificity of real-time elastography in the staging of advanced rectal cancer(T3)were 84%(42/50), 89.1%(41/46)and 25%(1/4), respectively. With the combination of the two techniques, the accuracy, sensitivity and specificity in the staging of advanced rectal cancer(T3)were 96%(48/50), 97.8%(45/46)and 75%(3/4), respectively. There was no significant difference in accuracy and sensitivity(χ2=4.000 and 3.100, P=0.373 and 0.542)between the three approaches. Kappa values between each of the three approaches and surgical pathology were 0.531, 0.252 and 0.728, respectively. Conclusions Real-time tissue elastography in the diagnosis and staging of advanced rectal cancer can be enhanced when used in combination with endorectal ultrasound. Key words: Rectal neoplasms; Elasticity imaging techniques

Effect of Inflammation on Fibrosis Staging Measured by Quantitative Elasticity Parameters in Rats With Immune Hepatitis.

To investigate the effect of inflammation on fibrosis staging measured by quantitative elasticity parameters in rats with immune hepatitis. Fifty-two rats were injected with swine serum as a model group, whereas 8 rats were injected with saline as a control group. Rats were randomly subjected to real-time tissue elastography biweekly. Tissue dispersion quantitative analysis was performed to obtain 12 quantitative elasticity parameters: relative mean value, standard deviation, blue area percentage, complexity, kurtosis, skewness, contrast, entropy, inverse difference moment, angular second moment, correlation, and liver fibrosis index. Subsequently, rats were euthanized, and liver specimens were taken for pathologic examination. The Kruskal-Wallis test was used for comparisons among groups. Spearman rank correlation analysis was used for correlation analysis. Receiver operating characteristic curves were used to optimize cutoff values and evaluate the diagnostic performance of the liver fibrosis index. Except for complexity, kurtosis, and correlation, the other 9 parameters had statistical differences (P < .05), and among these 9 parameters, the liver fibrosis index had the strongest correlation with fibrosis staging (r = 0.809; P < .05). Except for kurtosis and correlation, the other 10 parameters had statistical differences (P < .05), and among these 10 parameters, the liver fibrosis index had the highest correlation with inflammation grading (r= 0.766; P< .05). The fibrosis index cutoff values were 2.35 for stage S1 or higher (area under the curve [AUC], 0.940; sensitivity, 97.1%; specificity, 73.3%), 2.99 for stage S2 or higher (AUC, 0.865; sensitivity, 78.6%; specificity, 81.0%), 3.48 for stage S3 or higher (AUC, 0.924; sensitivity, 94.4%; specificity, 87.1%), and 4.05 for stage S4 (AUC, 0.933; sensitivity, 87.5%; specificity, 95.1%). Real-time elastography could be used to noninvasively evaluate fibrosis staging in rats with immune hepatitis. However, inflammation had an effect on the accuracy of this technique.

Value of ultrasonic elastic quantitative analysis technique of organization diffusion in adenomyosis

Objective To investigate the value of the ultrasonic elastic quantitative analysis technique of organization diffusion in adenomyosis. Methods Ninty-three patients with adenomyosis were divided into adenomyosis group (n=52) and adenomyoma group (n=41), and fourty healthy subjects were enrolled as control group. All subjects underwent conventional ultrasound and real-time tissue elastography. Eleven elastic characteristics of all the subjects were performed. Results Different characteristics of ultrasound elastography images appeared in different groups. The measured values of elastic characteristics were significantly different between case group and normal group (P 0.05). The cutoff values of every index were analyzed by ROC curve. The strongest specificity index was SD(99%), the highest sensitivity index was ASM(100%), and the highest accuracy index was IDM(94%). Conclusions The value of ultrasonic elastic quantitative analysis of organization diffusion technique in adenomyosis can improve the ultrasound diagnosis of this diease. Key words: Elasticity imaging techniques; Adenomiyosis

Diagnostic accuracy of real-time tissue elastography for breast cancer: a meta-analysis

Abstract Objective The present study aimed to determine the accuracy of real-time tissue elastography (RTE) for the diagnosis of breast cancer. Methods The search was conducted in the PubMed, Web of Science, Cochrane Library, and China Biology Medicine databases from inception through December 31, 2014, without language restrictions. The meta-analysis was conducted using STATA version 12.0 and Meta-Disc version 1.4. We calculated the summary statistics for sensitivity (Sen), specificity (Spe), positive and negative likelihood ratio (LR+/LR-), diagnostic odds ratio (DOR), and summary receiver operating characteristic (SROC) curve. Results Ten studies that met all inclusion criteria were included in the meta-analysis. A total of 608 malignant breast lesions and 1292 benign breast tumors were assessed. All breast lesions were histologically confirmed after RTE. The pooled Sen was 0.83 (95% CI = 0.79-0.86); the pooled Spe was 0.86 (95% CI = 0.84-0.88). The pooled LR+ was 9.87 (95% CI = 2.66-36.71); the pooled LR- was 0.20 (95% CI = 0.17-0.23). The pooled DOR of RTE for the diagnosis of breast cancer was 62.21 (95% CI = 33.88-114.24). The area under the SROC curve was 0.9334 (standard error = 0.00125). We found no evidence of publication bias (t = -0.57, P = 0.582). Conclusion RTE may have high diagnostic accuracy for the differential diagnosis of benign and malignant breast tumors. RTE may be a good tool for breast cancer diagnosis.

Assessment for diagnosis of lymph node metastasis in esophageal cancer using endoscopic ultrasound elastography.

BackgroundWe performed endoscopic ultrasound real-time tissue elastography to more accurately diagnose lymph node metastasis of esophageal cancer. The aim of this study was to evaluate the ability of EUS elastography to distinguish benign from malignant lymph nodes in esophageal cancer patients.MethodsThe present study had two steps. As the first step (study 1), we developed diagnostic criteria for metastatic lymph nodes using elastography and verified the validity of the criteria. Three hundred and twenty-two lymph nodes from 35 patients treated by surgical resection were included in the study. As the second step (study 2), we preoperatively examined the lymph nodes of esophageal cancer patients with EUS elastography and compared its diagnostic performance with that of the conventional B-mode EUS images. A total of 115 lymph nodes from 31 patients were included.ResultsIn study 1, lymph nodes were considered malignant if 50 % or more of the node appeared blue, or if the peripheral part of the lesion was blue and the central part was red/yellow/green. The sensitivity and specificity of the elastography were 79.7 and 97.6 % with an accuracy of 93.8 %, which was significantly higher than the values for conventional B-mode imaging. In study 2, the sensitivity and specificity of the EUS elastography were 91.2 and 94.5 % with an accuracy of 93.9 %, which was also significantly higher than the values for conventional B-mode EUS imaging.ConclusionsThe present study demonstrated that EUS elastography is useful for diagnosing lymph node metastasis of esophageal cancer.

Immediate Changes to Skin and Subcutaneous Tissue Strains Following Manual Lymph Drainage in Legs with Lymphedema.

To study the immediate impact of manual lymph drainage (MLD) on skin and subcutaneous tissue strains in legs with lymphedema using free-hand real-time tissue elastography (RTE). Skin and subcutaneous tissue strain measurements were taken at the middle of the inner thigh and calf by RTE in 20 legs with lymphedema of 18 patients (stage II: 11, late stage II: 7, stage III: 2) and in 70 legs of 35 normal subjects. In patients with lymphedema, the same measurements were repeated immediately following MLD. Significant negative correlations were found between pre-MLD strains and the MLD-induced changes in thigh and calf skin strains (thigh skin: p <0.01, calf skin: p = 0.05), but not in subcutaneous tissue strains. Pre-MLD intercepts of these regression lines were closer to normal values as compared to mean pre-MLD values (normal thigh skin: 0.54% ± 0.30%, calf skin: 0.25% ± 0.18%, Pre-MLD thigh skin: 0.39% ± 0.20%, calf skin: 0.17% ± 0.12%, Pre-MLD intercept of thigh skin: 0.48%, Pre-MLD intercept of calf skin: 0.31%). It appears that MLD did not simply soften the skin, but rather normalized it in terms of strain. However, this was not confirmed in the subcutaneous tissue.

Value of real-time tissue elastography for squamous cell carcinoma of the tongue

Value of real-time tissue elastography for squamous cell carcinoma of the tongue

Changes in the hardness of the gastrocnemius muscle during a Kendo training camp as determined using ultrasound real-time tissue elastography

Changes in the hardness of the gastrocnemius muscle during a Kendo training camp as determined using ultrasound real-time tissue elastography

Real-time tissue elastography as a evaluation of the assessment of papillary thyroid papillary carcinoma with cervical lymph node metastasis

Objective To compare real-time tissue elastography (RTE) and ultrasound in the diagnosis of papillary thyroid carcinoma (PTC) with cervical lymph node (LN) metastasis. Methods A retrospective analysis was carried out on the clinical data of 72 patients with PTC.Eighty-four LNs of them were performed with ultrasound-guided fine-needle aspiration biopsy.Patients were divided into two groups: with cervical lymph node metastasis group and without cervical lymph node metastasis group.All patients were reviewed their B-mode ultrasonography (BUS) on cervical lymph node and RTE on thyroid.RTE elasticity indices (EI) of mean (Emean), minimum (Emin), maximum (Emax) and the ratio of Emean in LNs and surrounding muscle (Emean-m) were measured at the thyroids.The performances of RTE and BUS in predicting of PTC with LN metastasis were compared and analyzed. Results The sensitivity and specificity of BUS on diagnosis of the cervical lymph nodes metastasis were 84.0% and 90.0%.The RTE Emea, Emax, Emin and SI in meta-static LNs were significantly higher than those in benign LNs(P=0.001, 0.002, 0.001, 0.007). The RTE results of PTC patients with lymph node metastasis was analyzed by ROC curve.The largest area was Emin.AUC was 0.918, the critical value was 0.240.AUC of SI was 0.896, AUC of Emean was 0.718, AUC of Emax was 0.670.The sensitivity and specificity were 94.0% and 99.4%, respectively. Conclusion Co-operation of RTE and BUS was more accurate than simple BUS in diagnosis of PTC with lymph node metastasis.SI and Emin has a high diagnostic value. Key words: Thyroid neoplasms; Ultrasonography; Neoplasm metastasis; Lymphatic metastasis

The stiff elastographic change of submandibular glands rapidly improves after the introduction of glucocorticoid treatment in patients with IgG4-related dacryoadenitis and sialoadenitis

In three patients with immunoglobulin G4-related dacryoadenitis and sialoadenitis (IgG4-DS), we assessed the changes in the hardness of affected submandibular glands by the real-time tissue elastography at baseline and 2 weeks after the initiation of treatment with oral glucocorticoids. Elastography revealed “blue” meaning to be a hard tissue matched the hypoechoic areas inside the enlarged submandibular glands before treatment. The stiff elastographic changes rapidly improved after 2 weeks. This may relate with the reversibility of salivary function by glucocorticoid treatment in patients with IgG4-DS.

Real‐time Tissue Elastography for Assessment of Liver Stiffness in Adults Without Known Liver Disease

To investigate normal liver stiffness and its influential factors in adults without liver disease using real-time tissue elastography. The liver stiffness threshold value for identifying patients with chronic liver disease was also determined. One hundred twenty healthy volunteers were examined with real-time tissue elastography. An integrated quantitative elastographic parameter, defined as the liver fibrosis index, was obtained by tissue dispersion quantitative analysis. Correlations between the liver fibrosis index and age, sex, and body mass index (BMI) were studied. To determine the threshold value for identifying chronic liver disease, 29 patients with chronic hepatitis B who underwent liver biopsy, including patients without fibrosis (fibrosis stage F0; n = 9) and patients with substantial fibrosis (F1-F2; n = 20) were also investigated. A receiver operating characteristic curve analysis for differentiating the F0 from the F1-F2 group was performed. There were no significant differences in the mean liver fibrosis index between sexes or among different age groups. There was a positive correlation between BMI and the liver fibrosis index. The mean liver fibrosis index ± SD in healthy participants with a normal BMI was 1.31 ± 0.25. The mean liver fibrosis index values for F0 and F1-F2 patients with a normal BMI were 1.47 ± 0.24 and 2.44 ± 0.49, respectively (P < .001). The optimal liver fibrosis index threshold value for discriminating normal liver from noncirrhotic chronic liver disease was 2.12 in participants with a normal BMI. Liver stiffness determined by real-time tissue elastography in healthy Chinese adults is not affected by age and sex but has a positive correlation with BMI. Real-time tissue elastography for assessment of liver stiffness can also be used for identification of substantial fibrosis in patients with chronic liver disease.

Usefulness of Intraoperative Real-Time Tissue Elastography During Laparoscopic Hepatectomy

Usefulness of Intraoperative Real-Time Tissue Elastography During Laparoscopic Hepatectomy

Noninvasive assessment of the activity of the shoulder girdle muscles using ultrasound real-time tissue elastography

The purpose of this study was to clarify whether the activity of the shoulder girdle muscles could be estimated by measuring the elasticity of these muscles under several levels of muscle contraction through ultrasound real-time tissue elastography (RTE). Ten healthy men performed submaximal voluntary contractions (MVC) in each manual muscle testing position for the middle deltoid, upper trapezius, supraspinatus, levator scapulae, and rhomboid major. The elasticity of these muscles was measured using ultrasound RTE during the task. The strain ratio of the muscle to an acoustic coupler was calculated as an assessment index of the muscle elasticity. Higher strain ratio values imply lower elasticity. In addition, the electromyographic activity was recorded from surface electrodes attached only to the middle deltoid and upper trapezius. The strain ratios were negatively correlated with the normalized root mean square values for the middle deltoid (r=−0.659, p<0.001) and upper trapezius (r=−0.554, p<0.001). The strain ratios of all the muscles decreased with an increase from 10% MVC force to 30% MVC force. Ultrasound RTE may be useful for noninvasively assessing the activity of the shoulder girdle muscles at certain shoulder positions with low levels of muscle contraction.

Effect of exercise-induced muscle damage on muscle hardness evaluated by ultrasound real-time tissue elastography.

PurposeTo assess the effect of exercise-induced muscle damage on muscle hardness and evaluate the relationship between muscle hardness and muscle damage indicators.MethodsSeven men (mean 25.3 years; 172.7 cm; 66.8 kg) performed the single-leg ankle plantar flexion exercise involving both concentric and eccentric contractions (10 sets of 40 repetitions). The hardness of the medial gastrocnemius (MG) was evaluated using ultrasound real-time tissue elastography before, from day 1 to 4, and day 7 after exercise. The strain ratio between the MG and a reference material was calculated. Simultaneously, we evaluated the magnetic resonance T2 value (an index of edema) of the triceps surae, the ankle dorsiflexion range of motion (ROM), and calf muscle soreness. Serum creatine kinase activity was assessed before, 2 and 4 h, and from day 1 to 4 after exercise.ResultsThe MG showed lower strain ratio, indicating increased muscle hardness, on day 4 post-exercise (P < 0.01) and higher T2 values on days 1–7 post-exercise (P < 0.01) relative to each pre-exercise value. The ankle dorsiflexion ROM was lower on days 2–4 post-exercise (P < 0.01). The serum creatine kinase markedly increased on days 3 and 4 post-exercise (not significant). The degree of muscle soreness among the post-exercise time points was similar. The decreased strain ratio did not correlate with the increased T2, the decreased joint ROM or muscle soreness.ConclusionMuscle hardness increased after strenuous resistance exercise, but the change was not related with muscle edema, decreased joint ROM, or muscle soreness resulting from muscle damage.