Objective: To investigate the best combined method of S-Detect, a computer-aided diagnosis (CAD) system, with breast ultrasound (US) according to radiologists’ experience.

Methods: From March 2019 to June 2019, 259 breast masses in 255 women were included in this study. Ultrasonographic images of the target masses were prospectively analyzed by radiologists and CAD. Three combined methods, including method 1 [selective downgrading combination for Breast Imaging Reporting and Data System (BI-RADS) 4a lesions], method 2 (selective upgrading combination for BI-RADS 3 lesions) and method 3 (selective upgrading or downgrading combination for BI-RADS 3 or 4a lesions), were applied to interpret the CAD results. The sensitivity, specificity, the area under the receiver operating characteristic curve (AUC) of experienced or inexperienced radiologists before and after adding CAD results were compared using the histopathological results as a reference standard.

Results: In identifying breast malignancy, the AUC for CAD was similar to that of experienced radiologists (P= 0.410), but higher than that of inexperienced radiologists (P= 0.003). When combining CAD with experienced radiologists based on method 1 and combining CAD results with inexperienced radiologists based on method 3, the AUCs were significantly improved (P= 0.024 and 0.003, respectively) compared to US alone, with significantly increased specificity (P< 0.001 for both) and no significantly decreased sensitivity (P> 0.05 for both).

Conclusion: The combination of CAD system and conventional ultrasound can improve ultrasound diagnostic performance in determining breast malignancy. The method 1 and method 3 combinations are respectively recommended for experienced and inexperienced radiologists when CAD is combined with conventional breast ultrasound.

Objective: Heavy metal pollution has become one of the environmental contamination problems in today's world. Adsorption materials can effectively remove heavy metal ions from the water. There are some shortcomings for traditional adsorbents, such as difficult separation after adsorption, long separation time, and may cause secondary pollution in the environment without recycling. The aim of this study was to seek new materials with effective ways to absorb heavy metal ions in the water.

Methods: A new kind of adsorption material consisted of polylactic acid (PLA) microbubble and graphene oxide (GO) (i.e., PLA@GO microbubbles) was fabricated which can combine by electrostatic adsorption with the assistance of PAH. The influence of the initial concentration of heavy metal of lead ion, pH value, and absorption time on the adsorption effect of PLA@GO microbubbles was tested in this study.

Results: Graphene oxide modified on PLA microbubble has huge specific surface area and various functional groups, which can adsorb heavy metal ions in water. The resulting PLA@GO microbubble showed a homogeneous spherical structure with a size of 500-1.5 μm, which was suitable for its effective separation from water. The optimal dosage of PLA@GO microbubbles was 10 mg, the pH value of the solution was 5.0, and the adsorption time was 20 minutes which correlates to 75 mg/L of leadions.

Conclusion: The characteristics of the PLA@GO microbubbles showed a strong adsorption capacity, high adsorption efficiency, and a shorter balance time which provided an environment-friendly new material to remove heavy metal ions from water.

Objective: To evaluate and compare the diagnostic performance of B-mode ultrasound (B-mode US), strain elastography (SE), color Doppler ultrasound (color Doppler US) and the combination of these modalities in differentiation between fibroadenomas and phyllodes tumors.

Methods: This retrospective study included 220 breast lesions, between January 2016 and January 2018. B-mode US, strain elastography, and color Doppler US were realized to evaluate each lesion. The results of three modalities were compared between the B-mode US and the combination of B-mode US, elastography, and color Doppler US: sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and area under the receiver operating characteristic curve (AUC). The pathological findings were used as the reference standard.

Results: Among 220 breast masses, 189 of the lesions were fibroadenomas, 31 were phyllodes tumors. Addition of strain elastography and color Doppler US to B-mode US increased the specificity from 27.5% (95% confidence interval [CI]: 21.15%, 33.88%) to 95.24% (95% CI: 92.20%, 98.27%; P < 0.001); PPV from 16.46% (95% CI: 10.79%,22.14%) to 60.87% (95% CI: 40.92%, 80.82%; P < 0.001) and AUC from 0.584 (95% CI: 0.481, 0.687) to 0.886 (95% CI: 0.824, 0.948; P < 0.001).

Conclusion: The combination B-mode US, strain elastography and color Doppler US increase the diagnostic performance in distinguishing fibroadenomas from phyllodes tumors.

Objective: To investigate the accuracy of contrast-enhanced ultrasound (CEUS) in the diagnosis and localization of active needle-tract bleeding (ANTB) during thermal ablation for liver cancer.

Methods: Between June 2013 and December 2018, liver cancer patients with poor coagulation function or suspected needle-tract bleeding during ablation were enrolled in the study. Conventional US and CEUS were applied to detect ANTB and the bleeding sites, and sequentially abdominal paracentesis drainage (APD) was used as the gold standard for the diagnosis of ANTB. Thermal ablation guided by conventional US or CEUS was used to stop the bleeding.

Results: Among the 77 enrolled patients, 21 patients (27.3%, 21/77) had ANTB. In total, four (19.0%) and 21 (100%) cases of ANTB were diagnosed by colour Doppler US and CEUS, respectively. The sensitivity, specificity and accuracy of colour Doppler US for diagnosing ANTB were 19.0%, 100% and 77.6%, respectively. The sensitivity, specificity, and accuracy of CEUS for diagnosing ANTB were 100%, 100% and 100%, respectively. The sensitivity of CEUS to diagnose ANTB was significantly higher than that of colour Doppler US (P < 0.001). All cases of ANTB were arterial bleeding and were stopped by thermal ablation under the guidance of colour Doppler US or CEUS.

Conclusion: Compared to colour Doppler US, CEUS could detect ANTB with significantly higher sensitivity and accurately guide needle-tract ablation during thermal ablation of liver cancer.

Objective: Transient tachypnea of newborn (TTN) and respiratory distress syndrome (RDS) are the most common causes of respiratory distress among preterm neonates. The aim of this study was to evaluate the accuracy of lung ultrasonography (LUS) for diagnosing and differentiating TTN and RDS in preterm neonates.

Methods: This was a prospective single center study. From January 2020 to June 2021 a total of 114 preterm neonates who were admitted to neonatal intensive care unit (NICU) with symptoms of respiratory distress within 6 hours of birth were subjected to clinical examination, laboratory testing, chest x-ray (AP and lateral view’s) and LUS. Their clinical course was closely monitored. On the basis of final diagnosis made on day three of admission they were divided into two groups, 37 diagnosed with TTN and 61 with RDS. Patients diagnosed with other conditions including neonatal pneumonia, meconium aspiration syndrome etc. were excluded from analysis. LUS findings in RDS and TTN were analyzed and compared to each other.

Results: Pulmonary edema manifesting as alveolo-interstitial syndrome, double lung point and less commonly as white out lungs in absence of consolidation had a 100% sensitivity and specificity in diagnosing TTN. A combination of three signs of consolidation with air or fluid bronchograms, white out lungs and absent spared areas has a 100% sensitivity and specificity for diagnosing RDS. Double lung point was seen only in infants suffering from TTN while consolidation with air or fluid bronchograms was only seen in cases of RDS.

Conclusion: Lung ultrasound can accurately diagnose and reliably differentiate TTN and RDS in preterm neonates. Hence LUS can become an initial screening tool in NICU.

Objective: In this paper, we retrospectively analyzed the ultrasonographic features of paratesticular leiomyoma to help doctors correctly diagnose the disease before operation and guide surgical treatment.

Methods: From 2013 to 2020, 16 cases of paratesticular leiomyomas confirmed by pathology in our hospital were retrospectively analyzed. The retrospective analysis included the ultrasound and color Doppler flow imaging (CDFI) of paratesticular leiomyoma which were evaluated by two experienced radiologists based on the features of ultrasound images of lesions.

Results: All the 16 paratesticular leiomyoma presented as hypoechoic masses with a clear boundary and round shape. The echotexture of 6 large leiomyomas showed a typical vortex appearance. In the remaining 10 small leiomyomas, thin cord-like hyper-echogenic appearance was found. Color Doppler flow imaging showed that the blood flow signal within a large leiomyoma mass (n = 1) was significantly higher than that of surrounding testis while the blood flow signals of the smaller leiomyomas (n = 5) had significantly less flow signals compared with the testis. The remaining leiomyoma masses (n = 10) had similar flow signals to the testicular blood flow.

Conclusion: Sonography can be used to detect testicular tumors and to differentiate extratesticular from intratesticular masses. The ultrasound features of paratesticular leiomyoma included hypo- and hyperechoic mass, a round or typical vortex shape as well as various vascularity based on the size of the tumors.

Objective: The aim of this study was to identify features of follicular thyroid neoplasm by conventional ultrasound (US) and contrast-enhanced ultrasound (CEUS) based on morphological and pathological correlations and make diagnostic strategy for predicting malignancy.

Methods: Conventional US and CEUS were performed in 21 follicular thyroid cancers (FTCs) and 35 follicular adenomas (FAs) that were pathologically approved. Sonographic features were retrospectively reviewed, and diagnostic performance were analyzed using pathology as reference standard.

Results: The most useful character in diagnosis of FTC by conventional US was round shape (OR=6.6), followed by absent of halo sign (Odds ratio, OR = 4.79) and calcification (OR = 3.875). Among all CEUS morphological and blow flow findings, incomplete rim enhancement pattern (OR = 19.2) and the presence of perfusion defects (OR = 5.454) were the most effective features to discriminate between FTC and FA. Based on the five discriminatory parameters, a diagnostic criterion was established to assess the risk of FTC. The sensitivity, specificity, positive predictive values (PPV), negative predictive values (NPV) and accuracy for predicting malignancy were 81.0 %, 80 %, 70.8 %, 87.5 % and 80.4%, respectively.

Conclusions: CEUS provided additional sonographic features which is helpful for predicting potentially malignancy of follicular thyroid neoplasm.

ObjectiveIntrathyroidal thymic carcinoma (ITTC) is a rare epithelial tumor of the thyroid gland. Since ITTC is rare, its imaging findings have not been well defined. In the present study, we studied the US appearance of ITTC by analyzing ten cases retrospectively.

Methods Patients were identified by searching the surgical pathology records at our hospital. There were three male and seven female patients ranging in age from 40 to 79 years. The ultrasound (US) features were evaluated, and the relevant clinical data were combined with the fine needle aspiration (FNA) results from previous publications.

Results The average length of the nodules was 48 mm. Of all ten nodules, half were located in the right lobe of the thyroid, and half were located in the left lobe, either immediately adjacent to the lower lobe or within the lower part of the thyroid lobe. All nodules manifested with a completely solid composition and heterogeneous hypoechoic echogenicity. Three nodules had striped hyperechogenicity within the nodule. All nodules had irregular margins. Seven had a horizontal shape, and three had a vertical shape. Four nodules manifested with mainly peripheral vascularity, two nodules showed mainly central vascularity, and three had mixed vascularity. The vascularity of one remaining nodule was unknown. Cervical lymph node metastasis was detected in two cases by US examination. According to previous literature, FNA cytology revealed atypical type of thyroid cancer, poorly differentiated carcinoma, or a high-grade malignant thyroid neoplasm without further definitive classification.

ConclusionA large cancer-like nodule located within the lower thyroid in middle-aged people, combined with an atypical type of thyroid cancer after FNA, indicated that ITTC should be considered.

Objective: To compare the etiologies and adverse outcomes of pregnancies with short fetal femur length (FL) categorized based on relative proportion and percentile placement.
Methods: Fetuses (n = 254) with short FL measured by ultrasound were classified into four groups: severe and disproportionate short FL (group A); severe and proportionate short FL (group B); mild and disproportionate short FL (group C); mild and proportionate short FL (group D). Etiologies and outcomes of pregnancies were compared between groups.
Results: A larger percentage of skeletal dysplasia occurred in group A (28.57%) than in the other three groups (group B: 1.85%; group C: 4.08%; group D: 0). Groups A and B also had higher rates (group A: 40.82%, group B:33.33%) of fetal growth restriction (FGR) than groups C and D (group C: 4.08%; group D:3.92%). No difference in chromosomal and genetic anomalies was detected among groups (P = 0.307); however, the rate of chromosomal and genetic testing in group A was higher than in group D (P = 0.001). Group A (57.14%) had a significantly lower rate of live birth than the other three groups, and group D (98.04%) had a higher live birth rate than groups B (87.04%) and C (83.67%). Considering only living fetuses, higher rates of preterm birth (P < 0.001), low birth weight (LBW) (P < 0.001), neonatal intensive care unit (NICU) admission or pediatric hospital referral (P = 0.004), Apgar score (1 min/5 min) ≤7 (P < 0.001) and fetal distress or neonatal asphyxia (P = 0.004) were found in group A compared to group D.
Conclusion: Fetuses with severe and disproportionate short FL should be flagged for possible skeletal dysplasia. Fetuses with severe short FL should be watched for FGR prenatally. Invasive prenatal tests are recommended for fetuses with severe and disproportionate FL but not recommended for those with mild and proportionate short FL. Outcomes of fetuses with severe and disproportionate short FL were worse than that of fetuses with mild and proportionate short FL.

Objective: To assess the viscoelasticity of the carotid artery using shear wave dispersion Imaging and to determine the relevant factors.
Methods: Ninety volunteers were recruited and divided into elder group and young group. Shear wave dispersion (SWD) imaging was applied to measure carotid viscoelasticity. The other arterial parameters, including arterial pulse wave velocity (PWV), inner diameter (CD), intima-medium thickness (CIMT), peak systolic velocity (PSV), mean flow velocity (MFV), and velocity time integral (VTI) of the common carotid artery (CCA) were also recorded by using ultrasound measurement.
Results: Measurements showed the SWD were lower, while CD, CIMT and PWV were higher in the elder group than those of young group. However, SWD was negatively correlated with VTI, and PSV respectively (r = -0.492 and -0.533, all P < 0.05). SWD was also positively correlated with MFV (r = 0.354, P < 0.05). In elder group, SWD was negatively correlated with PSV and PWV, respectively (r = -0.372 and -0.422, all P < 0.05) while in young group, SWD positively correlated with CD, CIMT and MFV (r = 0.531, 0.462 and 0.479 respectively, and all P < 0.05).
Conclusion: SWD imaging shown relationship with ultrasound parameters of carotid artery and has a potential for assessment of arterial viscoelasticity.

Objective: Imaging modalities for pancreatic intraductal papillary mucinous neoplasm (IPMN) often provide a large amount of information, and an adequate comparison of their diagnostic efficacies cannot be made by simply referring to the diagnostic accuracy rates. The aim of the study was to apply a novel scoring system to evaluate the pancreatic IPMN diagnostic efficacy of transabdominal ultrasound (TAUS), computed tomography (CT), and magnetic resonance imaging (MRI).

Methods: The clinical and diagnostic imaging data of 42 patients with pancreatic IPMN diagnosed at Fujian Medical University Union Hospital between January 2014 and November 2020 were retrospectively analyzed. We applied our scoring system for the quantitative, location, and qualitative diagnosis of each imaging modality, and the diagnostic efficacy was determined.

Results: The mean rank scores of quantitative diagnosis for MRI, CT, and TAUS were 53, 48.96, and 48.54, respectively (P = 0.267). The mean rank scores of location diagnosis for these three methods were 51.72, 49.58, and 48.97, respectively (P = 0.752). The mean rank scores of qualitative diagnosis for MRI, CT, and TAUS were 59.69, 41.08, and 51.18, respectively; the difference was statistically significant (P = 0.015).

Conclusions: The novel scoring system could comprehensively and accurately evaluate the diagnostic efficacy of TAUS, CT, and MRI for pancreatic IPMN. MRI had the highest quantitative, localization, qualitative, and comprehensive diagnostic efficacy.

Objective: To explore the feasibility of quantitative evaluation of cirrhosis by geometrical characteristics of hepatic capsule based on high-frequency ultrasound imaging.

Methods: Rabbits with models of cirrhosis were established and then were divided into four groups: control, 6-week, 12-week and 18-week groups. Two-dimensional high-frequency ultrasound images of hepatic capsule of all rabbits were collected to obtain hepatic capsual contours and key points refltected shapes of these contours (shape control points) which were approximated by the principle of vertical gradient maximization under the manual supervision. Subsequently, the number of continuous segments of the contour line, the mean value and variance of angles between adjacent seed points were extracted to evaluate the continuity and smoothness of the contour line of the hepatic capsule.

Results: With aggravating cirrhosis, the number of segments required to make the sum of lengths of continuous segments reach up to 80% of the total width of the imaging section was gradually increased. The differences between the control group and 18-week group (P = 0.025) as well as between 6-week group and 18-week group (P = 0.004) were statistically significant. Similarly, the mean value and variance of the angles were also gradually increased, and the differences between the control group and the 6-week (P = 0.015, P = 0.036), 12-week (P < 0.001, P = 0.002) and 18-week groups (P = 0.023, P < 0.001) were statistically significant. In addition, the difference in variance of angles between the 6-week group and 18-week group (P = 0.030) was statistically significant.

Conclusion: Sonographic analysis of geometrical characteristics of the hepatic capsule could be used to partially indicate the presence of early-stage cirrhosis, which could provide a quantitative method for non-invasive assessment of cirrhosis.

Objective: To investigate the correlation between the DCE-CT imaging biomarkers and histological biomarkers of tumor angiogenesis in adrenal adenomas and non-adenomas for the enhancement mechanism of DCE-CT.

Methods: Forty-two patients with 45 adrenal masses including 27 adenomas and 18 non-adenomas diagnosed pathologically were enrolled in this study. The features of DCE-CT (imaging biomarkers) and tumor angiogenesis (histological biomarkers) in adrenal masses were evaluated, and their correlations were explored.

Results: The enhanced features of DCE-CT in adrenal masses were classified: rapid washout group and slow washout group. Type A and C of time density (TD) curves, relative washout rate (Washr) ≥34%, and absolute washout rate (Washa) ≥43% belonged to the rapid group. In contrast, type B, D and E, Washr <34%, and Washa <43% belonged to the slow group. There was significant difference between the biomarkers of DCE-CT in adrenal masses. The rapid group was mainly found in adenomas, whereas the slow was mainly present in nonadenomas. The tumor angiogenesis, histological biomarkers, including microvessel density (MVD), vascular endothelial growth factor (VEGF), and microvascular ultrastructures demonstrated significant difference between the rapid and the slow washout group revealed by DCE-CT. The MVD and VEGF expression in rapid group were remarkably higher than those in slow group. Meanwhile, the tumor angiogenesis was also significantly different between adenomas and nonadenomas. The MVD and VEGF expression were also significantly higher in adenomas than those in nonadenomas. Furthermore, different microvascular ultrastructures were identified between adenomas and nonadenomas, which were in accordance with those between the rapid and the slow group. Microvascular ultrastructures in adrenal adenomas and/or the rapid group showed regular lumens and nonstenosis; more pinocytotic vesicles and fenestrations of endothelium; widening of the intercellular space; uniform thinning and better integrity of basal membrane; regular and uniform thinning, along with less stroma of extra vessel space. In comparison, opposite microvascular ultrastructures, in adrenal nonadenomas and/or the slow group.

Conclusion: The close correlation of DCE-CT imaging biomarkers and histological biomarkers of tumor angiogenesis was found between adrenal adenomas and nonadenomas. Tumor angiogenesis in adrenal adenomas and nonadenomas were shown the different enhancement characteristics at DCE-CT.

Objective: The present study aimed to determine the efficacy and safety of a newly designed microwave ablation (MWA) system in ex vivo and in vivo liver model.
Methods: A new MWA system (HRMW-01, Hengrui Medical, Guangzhou, China) was tested on porcine liver ex vivo with different parameter settings (50-70 W for 5-20 min). Ablation volums were measured on the gross specimens. In an in vivo study, MWA was performed at 60 W for 5 min in canine liver. Ablation volumes were identified and measured using contrast-enhanced ultrasound (CEUS) 1 w after the ablation. All animals underwent routine hematological, biochemical, and coagulation tests before ablation at 1 d and 1 w after ablation. For comparison, radiofrequency ablation (RFA) was performed using a Cool-tip system (Valleylab, Boulder, CO, USA) with an automated power setting for 12 min in both ex vivo and in vivo studies.
Results: In ex vivo studies, the mean volumes of MWA coagulation ranged from 27.8 ± 7.3 cm³ to 144.6 ± 35.9 cm ³ and increased with ablation duration and power output. MWA was prone to creating larger volume but less spherical ablation shape than RFA (P < 0.05). In in vivo studies, MWA created larger ablation volumes with shorter ablation time compared to RFA (P < 0.05). Laboratory data showed significantly higher alanine aminotransferase and aspartate aminotransferase levels 1 d after ablation than based line levels (P < 0.05) while the levels decreased close to pre-ablation levels 1 w after ablation (P > 0.05).
Conclusion: The newly designed MWA system is safe and more efficient than a commonly used RFA system. However, further clinical studies are warranted.

Objective: To evaluate the curative effect of lauromacrogol foam sclerotherapy of uterine fibroids via transvaginal ultrasound-guided injection.
Methods: Thirty premenopausal women with a total of thirty-one uterine fibroids were recruited consecutively and underwent transvaginal 3D-Power Doppler Angiography (PDA) at 0, 1, 3, and 6 months. Written informed consent was obtained from all of the patients. The changes in the fibroid 3D volume and relationships between the fibroid location and blood supply were analyzed. The relief of clinical symptoms and improvement in health-related quality of life (HRQL) were evaluated using the uterine fibroid symptom and quality-of-life (UFS-QOL) questionnaire before and after treatment for 6 months; adverse events were also assessed.
Results: The mean baseline volumes ± SD were 61.2 ± 71.5 cm³ (range, 4.1 cm³ - 340.4 cm³) for the dominant fibroid. The mean values of percentage reduction in fibroid volume at 1, 3 and 6 months were 23.9% (range, 5.2% - 42.1%; 95%CI, 20.6% - 27.3%), 43.4% (range, 21.8% - 67.4%; 95%CI, 39.0% - 47.8%), and 60.0% (range, 31.8% - 83.2%; 95%CI, 55.2% - 64.9%), respectively, and the reduction was correlated with the location and blood supply. Additionally, the blood flow to the fibroids was markedly decreased. The clinical symptoms were greatly alleviated or even completely resolved, and the HRQL was notably improved (P < 0.001). Mild abdominal pain, paleness, vomiting, and cold sweat were most commonly reported adverse effects.
Conclusion: Ultrasound-guided sclerotherapy of uterine fibroids with foam lauromacrogol is a simple, safe and useful method with a wide application prospect.

Objective: Although rhesus macaques and human beings share many fundamental biological characteristics, including underlying genes and physiological processes, the similarity and difference of cerebrovascular hemodynamic have not been well investigated. We aimed to examine and compare the intracranial and extracranial hemodynamics between these two species.
Methods: A total of 10 adult male rhesus and 20 age-matched healthy men were recruited in this study. The somatometric measurements (BMI, HR, and BP) and ultrasonography examinations (carotid arteries and middle cerebral artery) were performed on both groups.
Results: We found a few similarities in somatometric measurements (BMI, waist-hip ratio and mean artery pressure), mean velocity ratios of internal carotid artery (ICA)/external carotid artery (ECA) and ICA/vertebral artery (VA), and the resistance index both in ICA and ECA between rhesus macaques and humans. However, faster HR (103 ± 12 vs. 73 ± 14 beat/min, P < 0.01), higher pulse pressure (89.5 ± 8.9 vs. 48.1 ± 6.3 mmHg, P < 0.01), smaller diameter ratio of bilateral ICA/ECAdia (P < 0.01), elevated middle cerebral artery pulsatility index (P < 0.01) and higher cerebrovascular resistance (2.42 ± 0.59 vs. 1.54 ± 0.35, P < 0.01) were found in rhesus when compared with humans.
Conclusions: This study leads to a better understanding of cerebral neuroanatomy in rhesus macaques, and it has several important implications for future cerebrovascular translational researches.

Objective: To evaluate the technical success rate and reproducibility of sound touch elastography (STE) and sound touch quantification (STQ) in liver and spleen stiffness measurement and the reference ranges of normal liver and spleen stiffness. We also compared with a previous validated acoustic radiation force impulse (ARFI) technique.
Methods: Two hundred and fifty-three healthy adults and 40 chronic hepatitis B patients were recruited. All patients underwent liver and spleen stiffness measurements using STE, STQ, and ARFI. A hundred and five patients (36 patients with chronic hepatitis and 69 healthy adults) were examined twice, by two trained sonographers who are familiar with STE and STQ techniques independently. Another 36 healthy adults were examined twice by ARFI imaging. The technical success rates and reproducibility were evaluated.
Results: The success rates of STE, STQ, and ARFI were 96.5%, 95.1%, and 94.8% in liver, and 87.5%, 84.0%, and 78.0% in spleen, respectively. The inter-observer reproducibility of STE, STQ and ARFI were 0.914, 0.896, and 0.845 in liver, and 0.629, 0.601, and 0.543 in spleen, respectively. When the thickness of spleen was greater than 30mm, the reproducibility was 0.704 in STE and 0.668 in STQ. The normal ranges of liver stiffness were 5.80-6.04 kPa measured by STE and 5.87-6.13 kPa measured by STQ, and normal spleen stiffness ranged from 14.83-15.54 kPa measured by STE and 15.85-16.62 kPa measured by STQ.
Conclusion: Our study showed STE and STQ in liver and spleen stiffness measurement had a high success rate with good reproducibility, which were comparable to ARFI. The inter-observer reproducibility of spleen was barely satisfactory, but was good when the thickness of spleen was greater than 30mm.

Objective: Using brain-dead donors to obtain organs for transplant is an effective way to overcome the shortage of organ donors. The purpose of this study is to investigate ultrasound flow imaging and elastography as a simple, feasible, accurate and effective method for evaluation of liver damage after brain death using an animal model.
Methods: We established a brain-death model using 15 pigs. Brain death was induced by progressively increasing the intracranial pressure, and the brain-death state was maintained for 9 hours. Spectral Doppler imaging and elastography was used to evaluate hepatic hemodynamic parameters and tissue stiffness over the period of brain death.
Results: Electron microscopy of the liver over the progress of brain death revealed gradual mitochondrial swelling (with rupture), expansion of the endoplasmic reticulum, and increased collagen in the extracellular matrix. Spectral Doppler imagin demonstrated that the HA-RI increased over time, which had statistically significant difference between the Bef-BD measurement and measurements at 3, 6, and 9 hours after brain death. Real time elastography of the liver revealed a gradual decrease of the mean relative strain value (MEAN) over the time, and a gradual increase in standard deviation of the relative strain value, complexity of low strain area, and skewness, suggesting that brain-death induced liver damage increases with time. The ROC curves showed that MEAN had the highest sensitivity, specificity, and accuracy for assessing liver injury.
Conclusion: Hepatic tissue damage induced by brain death increased over time. The HA-RI and liver stiffness index changes can be assessed by Doppler ultrasound and elastographic imaging. Our results showed that elastography is a useful method to evaluate liver damage after brain death.

Objective: Intrapulmonary artery mass is rare and prone to be misdiagnosed. The purpose of this study was to retrospectively review the evaluation of intrapulmonary artery masses by ultrasound imaging, summarize their characteristics, and suggest a standardized approach for clinical management.
Methods: Sixteen patients were enrolled in the study. Transthoracic echocardiography (TTE) showed a mass attached to the major pulmonary artery (MPA) trunk, straddling the bilateral pulmonary arteries or pulmonary valve (PV). The masses were diagnosed based on the site of the attachment, shape, size, mobility, and other morphological characteristics on ultrasound imaging examination. The pathological data were collected and analyzed from medical records.
Results: TTE images showed that the intrapulmonary artery mass was most frequently located in the MPA trunk. Eight patients had a pathological diagnosis and underwent complete mass resection. Five patients were suspected as having pulmonary thromboembolism (PTE) and were prescribed anticoagulation therapy, after which the masses decreased or disappeared on follow-up TTE. Three patients with suspected metastatic tumors died during hospitalization and had no pathological data. The 16 patients had the following distribution of diagnoses: thrombus (32%; 5/16), vegetations (12%; 2/16), primary benign lesions (12%; 2/16), primary malignant tumors (19%; 3/16), and metastatic tumors (25%; 4/16).
Conclusion: The majority of intrapulmonary artery masses were thrombi or primary pulmonary artery sarcomas. Primary tumors are much more common than metastatic tumors in the intrapulmonary artery.

Objective: To explore differentially expressed genes (DEGs) between lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC).
Methods: Based on GEO database, we used R software to identify the DEGs and conducted the bioinformatics analysis to explore the molecular mechanisms of DEGs and constructed PPI network to find the key DEGs. Then we assessed the effect of the eligible key DEGs on survival in LUAD by Kaplan-Meier plotter online tool.
Results: GSE10245 was downloaded from the GEO database, which contained a total of 58 tissue samples, including 18 LUSC and 40 LUAD. We identified 784 DEGs between LUAD and LUSC. DEGs were enriched in statistical significant GO annotation 201 items and KEGG pathways 17 items. By constructed PPI network, we obtained 10 hub genes. Of which, five genes were significantly correlated with the overall survival of LUAD.
Conclusions: P2RY1, CHRM3, LPAR3, NMU, and S1PR5 may be the potential prognostic markers and therapeutic targets for LUAD.

Objectives: To investigate the causes, differential diagnosis, and clinical significance of absent blood flow (ABF) in the testis detected by color Doppler ultrasound (CDU) in acute scrotum.
Methods: A total of 263 patients with ABF in the testis detected by CDU in our hospital were reviewed retrospectively. However, only 111 patients who underwent surgery were included in this study. The ultrasonographic features of the testis and paratesticular tissue were analyzed. The surgical or surgical-pathologic results were taken as the reference standard to determine the causes of ABF in the testis.
Results: The causes of ABF in the testis were testicular torsion (n = 98, torsion group) and non-testicular torsion related diseases (n = 13, non-torsion group, including 8 testicular rupture, 3 epididymitis-orchitis combination with testicular necrosis, and 2 tumors). Tunica albuginea of the testis, diffuse enlarged epididymis, whirlpool sign, and internal echo of the testis were the better parameters for diagnosing the causes of ABF in the testis detected by CDU. And the accuracies of these approaches were 93.7%, 91%, 83.8%, and 81.1%, respectively. Whirlpool sign had a 100% positive predictive value (PPV), and disrupted tunica albuginea of the testis and diffuse enlarged epididymis each had 100% specificity for predicting testicular torsion. When the ultrasonographic findings were combined with these methods to determine the causes, the accuracy was 96.4% (107/111).
Conclusion: ABF in the testis detected by CDU is not always indicative of testicular torsion in acute scrotum; Analyzing ultrasound findings of the testis and paratesticular tissue can help with differential diagnosis of the causes of ABF in the testis and guide clinical decision-making.

Objective: This study evaluated the performance of automated machine-learning to diagnose non-alcoholic fatty liver disease (NAFLD) by ultrasound and compared these findings to radiologist performance.
Methods: 96 patients with histologic (33) or proton density fat fraction MRI (63) diagnosis of NAFLD and 100 patients without evidence of NAFLD were retrospectively identified. The “Fatty Liver” label included 96 patients with 405 images and the “Not Fatty Liver” label included 100 patients with 500 images. These 905 images made up a “Comprehensive Image” group. A “Radiology Selected Image” group was then created by selecting only images considered diagnostic by a blinded radiologist, resulting in 649 images. Cloud AutoML Visionbeta (Google LLC, Mountain View, CA) was used for machine learning. The models were evaluated against three blinded radiologists.
Results: The “Comprehensive Image” group model demonstrated a sensitivity of 88.6% (73.3-96.8%) and a specificity of 95.3% (84.2-99.4%). Radiologist performance on this image group included a sensitivity of 81.0% (74.3-87.6%) and specificity of 86.0% (72.6-99.5%). The model’s overall accuracy was 92.3% (84.0-97.1%), compared with mean individual performance (83.8%, 78.4-89.1%). The “Radiology Selected Image” group model demonstrated a sensitivity of 88.6% (73.3 - 96.8%) and specificity of 87.9% (71.8-96.6%). Mean radiologist sensitivity was 92.4% (86.9-97.9%) and specificity was 91.9% (83.4-100%). The model’s overall accuracy was 88.2% (78.1-94.8%) which was comparable to the individual radiologist performance (92.2%, 90.1-94.2%) and consensus performance (95.6%, 87.6-99.1%).
Conclusions: An automated machine-learning algorithm may accurately detect NAFLD on ultrasound.

Objective: To quantitatively analyze the difference of texture features of skeletal muscle in high-frequency ultrasound images under different physiological states using the multiscale decomposition method of ultrasound echo intensity interface reflections.
Methods: High frequency ultrasound images of the biceps brachii in different physiological states were collected from 20 healthy volunteers. In offline state, eight texture parameters including mean of texture gray scale (Mean), standard variance (SDev) of gray scale, number of blobs (NOB) of texture density, irregularity (IRGL) of texture primitive shape, mean size of blobs (SOB) of texture primitive, homogeneity of distribution (HOD) of texture uniformity, directionality of texture distribution (DOD), and periodicity of texture distribution (POD) were extracted by MATLAB software and compared and analyzed statistically.
Results: With the use of high frequency ultrasound, all healthy volunteers' biceps brachii showed isoechoic muscle bundles, organized arrangement of muscle fibers, and distinct and intact texture of structure. In different physiological states of biceps brachii of the same gender group, the NOB and the Mean showed statistically differences (P < 0.05). In the relaxation state of biceps brachii between different gender groups, the average SOB and the DOD showed statistically differences (P < 0.05). In the load state of biceps brachii between different genders, the NOB and the Mean showed statistically differences (P < 0.05).
Conclusions: The ultrasonic image changes of muscle fibers under different physiological states can be identified by quantitative texture characteristic parameters, providing more information for clinical computer-aided diagnosis of skeletal muscle injury.

Objective: To investigate whether contrast-enhanced ultrasound (CEUS) is helpful for assessing the disease activity of Takayasu arteritis (TA).
Methods: Eighty-four patients with TA were examined with ultrasound (US) and CEUS. Intima-media thickness (IMT) of both sides of the common carotid artery was measured for each patient. Semiquantitative analyses of contrast enhancement within the arterial wall were performed with a visual interpretation scale. Disease activity was determined by one experienced physician based on Physician Global Assessment criteria.
Results: Carotid CEUS revealed that 6 arteries showed no enhancement (7.1%, 6/84) while 78 arteries showed homogeneous enhancement within the thickened wall (92.9%, 78/84). Grade 1 enhancement was noted in 40 patients, and grade 2 in 38 patients. IMT of the active group was significantly thicker than that of the inactive group (2.4 ± 0.9 mm vs. 1.8 ± 0.5 mm, P = 0.001) on B-mode US, and slightly correlated with ESR (r = 0.344, P < 0.05) and CRP (r = 0.261, P < 0.05). Grade 2 enhancement was observed more in the active patients (61.7% vs. 41.3%, P = 0.001) on CEUS.
Conclusions: CEUS is a convenient and non-invasive imaging modality that is useful for evaluating disease activity in TA patients by assessing the vascularization within the carotid wall.

Background: To evaluate the diagnostic performance of a novel two-dimensional quantitative shear wave elastography (SWE) of virtual touch tissue imaging quantification (VTIQ) in the differential diagnosis between benign and malignant thyroid nodules.
Methods: Two hundred and six solid thyroid nodules were included in this prospective study. Conventional ultrasound and VTIQ examinations were performed. The diagnostic performances of US, VTIQ, and the combination of the two methods were compared. The usefulness of VTIQ in different size of nodules was also assessed.
Results: There were 113 benign nodules and 93 malignant nodules on fine needle aspiration (FNA) or histology. The shear wave velocities (SWVs) in malignant nodules were all significantly higher than those in benign nodules (SWV max: 4.01 ± 1.72 m/s vs 3.25 ± 1.01 m/s, SWV min: 2.87 ± 0.69 m/s vs 2.46 ± 0.67 m/s, SWV mean: 3.33 ± 0.89 m/s vs 2.85 ± 0.81 m/s, SWV median: 3.31 ± 0.88 m/s vs 2.82 ± 0.77 m/s, all P value < 0.001). After combined VTIQ with ultrasound, the diagnostic performances improved compared with ultrasound alone or VTIQ alone. As for lesions of different sizes, areas under curve (AUC) for the largest diameter of nodules ≤ 1.0 cm was 0.711, which was lower than that for the largest diameter of the nodules > 1.0 cm (AUC was 0.862) (P < 0.05). Conventional ultrasound features such as halo sign and microcalcification were predictors for lymphatic metastasis in malignant thyroid nodules (P < 0.05).
Conclusions: VTIQ is a new method for measuring stiffness of thyroid lesions qualitatively. The diagnostic performance of combined using VTIQ and conventional ultrasound was better than that of using either alone. Malignant thyroid nodules with conventional ultrasound features such as halo sign and microcalcification were more likely to have lymphatic metastasis. The evaluation of small thyroid lesions remained a difficult problem.

Objective: To investigate the diagnostic value of ultrasound-guided water enema for children with secondary intussusception.
Methods: We performed a retrospective analysis of the sonographic findings of 52 children with a confirmed diagnosis of SI through colonoscopy or surgical pathology between May 2016 and May 2019 in Shenzhen Children’s Hospital. The diagnostic value of ultrasound-guided water enema was evaluated.
Results: Of the 52 patients with SI (29 male, 23 female; average age, 50 months [range: 3 months to 12 years]), 16 had intestinal polyps, including 15 cases of juvenile polyps and 1 case of Peutz-Jeghers (P-J) polyps; 14 had Meckel's diverticulum; 11 had lymphoma; 10 had intestinal duplication; and 1 had jejunal schwannoma. All 52 patients were diagnosed with intussusception, of which 41 were confirmed with the presence of pathological lead points (PLPs) before water enema. After enema, PLP was demonstrated in 48 cases. All of the remaining 4 cases without a PLP diagnosis were found to be Meckel’s diverticulum. Ultrasonography revealed the specific features in each category. Patients with juvenile polyps showed hypoechoic masses in the intestinal lumen and some honeycomb-like anechoic masses while the single P-J polyp case showed hypoechoic masses with branching echoes in the intestinal lumen. Three of the Meckel’s diverticula cases showed irregular hyperechoic masses inside the intussusception, and 7 showed cystic masses inside the intussusception. All 11 lymphomas cases showed extremely hypoechoic masses. All 10 intestinal duplication cases showed cystic masses at the neck or inside the intussusception, with walls exhibiting intestinal wall-like structure. The case of jejunal schwannoma showed irregular hypoechoic masses at the neck of the intussusception. There were no major complications such as intestinal perforation occurred in all the children after the completion of water enema ultrasound examination.
Conclusion: Ultrasound-guided water enema helps identify PLPs and improves the diagnosis of primary diseases in children with SI.

Objectives: To investigate the clinical value of ultrasound in the diagnosis and treatment of reninoma.
Methods: We retrospectively analyzed the ultrasound findings of 9 patients with reninoma confirmed by pathology after surgical resection in our hospital between September 2012 and August 2019. All patients underwent conventional preoperative ultrasonography. Three underwent contrast-enhanced ultrasound (CEUS) and 3 with complete endogenetic tumor underwent intraoperative ultrasonography.
Results: Of the 9 patients with conventional ultrasound, 7 had renal space-occupying lesions and 2 had missed diagnosis. A hypoechoic or hyperechoic solid mass with regular morphology, clear boundary, capsule, weak echo halo around the mass, incomplete thin strip color blood flow signal around the mass were shown in 7 cases. Color Doppler displayed color flow signal of the incomplete thin strip around the mass and arterial blood supply with an internal thin branch. In 3 patients (including 2 with missing diagnosis by conventional ultrasound) who underwent preoperative contrast-enhanced ultrasound, the reninoma manifested as low enhancement, and the perfusion pattern showed as slow wash-in and slow wash-out compared with normal renal cortex. In 3 patients (including 2 cases of missed diagnosis by conventional ultrasound) with completely endogenic reninoma, intraoperative ultrasound clearly showed the tumor characteristics, and all successfully underwent laparoscopic ultrasound-guided partial nephrectomy.
Conclusions: Preoperative conventional ultrasound combined with CEUS, and clinical features, are helpful for the qualitative diagnosis of reninoma. Laparoscopic partial resection is the first-choice treatment for reninoma. Intraoperative ultrasound can provide real-time imaging, accurately evaluate the tumor status, and provide important information for surgeons.

Objectives: To compare the features of the time-intensity curve (TIC) of hepatocellular carcinoma (HCC) by two different contrast-enhanced ultrasound (CEUS) methods: Contrast Pulse Sequencing (CPS) and Contrast Harmonic Imaging (CHI).
Methods: This prospective study included 22 HCC lesions. The CPS and CHI (Cadence? technique by Siemens) were performed in random order for each lesion, and the microbubbles were completely cleared between the two methods. The imaging by each method was recorded for 10 minutes. The CEUS video clips were analyzed off-line and the quantitative parameters of time intensity curve were obtained: the peak intensity (PI), time to peak (TTP), washout time (WT), relative value (RV) of intensity and AUC before WT and after WT, and the time of RV ≥15 dB lasted (RLT).
Results: Compared with CPS, CHI showed an earlier WT (64.0 ± 17.1 s vs 33.1 ± 7.0 s) of HCC lesions, a lower RV of intensity (36.8 ± 9.4 vs 10.3 ± 5.1) and AUC (1377.2 ± 205.7 vs 227.2 ± 56.7) before WT, but higher RV of intensity (17.8 ± 4.6 vs 32.2 ± 8.6) and AUC (1 124.1 ± 276.4 vs 2 664.1 ± 456.8) after WT, and longer RLT (121.4 ± 49.8 s vs > 150 s).
Conclusion: For long later phase observation after washout, CHI is better than CPS, but the observation of rapid perfusion before washout is not comparable to CPS. A combined use of these two methods is recommended based on our research.

Objective: To discuss the value of bedside ultrasound in the diagnosis and treatment of 2019 novel coronavirus diseases (COVID-19).
Methods: Retrospective analysis of the results of bedside ultrasound of 510 patients with COVID-19 in our hospital was done from January 31, 2020 to March 4, 2020.
Results: (1) Among the 510 patients who underwent bedside ultrasound examination, a total of 327 (64.1%) underwent echocardiography, 494 (96.9%) underwent bilateral venous ultrasound examination of lower limbs, 86 (16.9%) underwent bilateral artery ultrasound examination of lower limbs, 48 (9.4%) underwent ultrasound examination of liver, gallbladder, spleen and pancreas, 26 (5.1%) underwent ultrasound examination of kidney, ureter and bladder, and the numbers of patients who underwent ultrasound examination of pericardium, pleural effusion, and peritoneal effusion were 16 (3.1%), 21 (4.1%), and 5 (1%), respectively. (2) Among the 327 patients who underwent bedside ultrasound examination of the heart, 96 (29.4%) showed results of positive for other abnormalities or complications, in which 31 (9.5%) had abnormal left ventricular wall motion, 42 (12.8%) were with valvular heart disease, 3 (0.9%) showed coronary heart disease, 19 (5.8%) showed the enlargement of right heart with pulmonary hypertension (PAH), and 1 (0.3%) had congenital heart disease. In addition, 6 of the 327 echocardiography patients showed negative results (no other abnormalities or complications), accounting for 1.8%. (3) Among the 494 patients who underwent bilateral venous examination of lower limbs, 182 (36.8%) had phlebothrombosis. Eighty-six (86) patients underwent bilateral artery examination of lower limbs, and 63 (73%) of them had positive results, in which 5 patients showed arterial occlusion and the other 57 patients showed atherosclerosis. (4) Thirty-three (33) patients underwent ultrasound examination of liver, gallbladder, spleen, and pancreas, and 23 (70%) of them showed positive results. Among the 26 patients who underwent the urological examination, 7 (26.9%) showed positive results. Additionally, there are 2 positive findings in 21 patients who underwent the examination of pleural effusion (9.5%), and 1 positive case in 5 patients who underwent the examination of abdominal effusion (20%).
Conclusion: Bedside ultrasound is important in the diagnosis and treatment of COVID-19. We hope to make better use of bedside ultrasound to help clinicians get accurate diagnosis and treatment strategies.

Objective: To investigate the value of lung ultrasound (LUS) in asymptomatic patients with confirmed COVID-19.
Methods: A retrospective analysis was performed on nine patients in a designated isolation hospital in Sanya from February 22nd, 2020 to February 23rd, 2020. All patients were confirmed with COVID-19 pneumonia by PCR test, but none had the typical symptoms of COVID-19. All patients first underwent LUS examination and then chest computed tomography (CT) scanning. The application value of LUS in asymptomatic confirmed patients with COVID-19 was evaluated, compared with chest CT which was regarded as the golden standard.
Results: Among nine asymptomatic patients with COVID-19, there were two cases (22.22%) with abnormal ultrasonic manifestations, of which one (11.11%) showed a fusion B3-line in zone 5 of the right lung, and the other showed localized pulmonary consolidation in zone 6 of the left lung. The remaining seven cases (77.78%) showed no abnormal changes in LUS, but only clear pleura sliding sign and A-line. Chest CT showed abnormal changes in three cases (33.33%). Two of them (22.22%) showed flocculent high-density shadow at the base of both lungs (especially in the right lung), while the other case showed ground-glass opacity with thickened interlobular septal in the left lower lobe, involving the pleura. There were no abnormalities on chest CT of the remaining six cases (66.67%). The two (22.22%) LUS-positive patients were in complete coincidence with CT-positive patients. This study showed that the coincidence rate of the two examination methods was 88.89%. Taking chest CT as golden standard, the sensitivity, specificity, positive predictive value, negative predictive value, and Kappa value of lung ultrasound in the diagnosis of COVID-19 were 66.67%, 100%, 100%, 85.71%, and 0.727, respectively.
Conclusion: LUS can evaluate lung lesions in asymptomatic patients with COVID-19. Compared with chest CT, the diagnostic coincidence rate and diagnostic consistency of LUS are relatively higher. For this asymptomatic type of patient, ultrasound can be used as a diagnosis method, which can avoid the risk of radiation exposure in a short period of time. As a rapid and dynamic assessment method, LUS can cooperate with remote consultation to provide timely and accurate guidance for clinical diagnosis and treatment when necessary.

Objectives: To analyze the progression manifestations and characteristics of pulmonary lesions in patients with COVID-19 by bed-side pulmonary ultrasonography.
Methods: A total of 20 COVID-19 patients admitted to the hospital from January to March in 2020 were retrospectively recruited. All cases were diagnosed according to the "Novel Coronavirus Pneumonia Treatment Protocol (Trial 7th edition)". The imaging characteristics of bed-side pulmonary ultrasonography were analyzed and summarized during the different disease stages.
Results: The average course of disease was 21.2 days, including 10.5 days of the progression period and 10.7 days of the recovery period. The ultrasound images of the patients were mainly presented as unsmoothed or interrupted pleural line, and B-line distribution was observed in all cases (20/20,100%). The "inflatable signs" in the consolidation lesion were visualized in 16 cases (16/20, 75.00%). In progressive stage, the ultrasound image changed from B-line sign to sieve-like consolidation, then the consolidation aggravated from patchy to chunk-like gradually, with the decreasing air bronchogram sign within the consolidation lesion. While the imaging characteristics of the ultrasound in the recovery stage were opposite to the progress stage, Color mode showed that the perfusion in the lesions of consolidation gradually increased as well.
Conclusion: The ultrasonic manifestations of COVID-19 patients had certain characteristics in the different disease stages. The application of ultrasound in these patients could provide imaging evidence in evaluation of the disease courses and therapeutic efficacy.

Objective: To investigate the feasibility of evaluating imaging changes pre-and post-treatment in Corona Virus Disease 2019 (COVID-19) patients by transthoracic pulmonary ultrasound.
Methods: A total of 8 patients diagnosed with severe or critical COVID-19 pneumonia were recruited, and then ultrasound scanning was performed to evaluate the pulmonary imaging changes pre- and post-treatment based on a modified ultrasonic Buda protocol. The correlation between chest high resolution computed tomography (HRCT) Warrick scoring and ultrasonic results was analyzed.
Results: The main manifestations of ultrasonic imaging in severe or critical COVID-19 patients were: (1) pleural thickening (8/8), blurry or irregular fragmentation (6/8), and discontinuous fragmentation (4/8); (2) pulmonary lesions: B-line sign (2/8), partial or complete fusion of B-line (white lung) (8/8), and pulmonary or subpleural small consolidation (C-line sign) in severe cases (3/8); and (3) rarely, pleural effusion or pulmonary gas cyst (1/8). The imaging results, which were evaluated followed by a modified Buda transthoracic pulmonary ultrasound protocol, were highly correlated with HRCT Warrick scoring (r = 0.715, P < 0.05). Meanwhile, both ultrasonic and HRCT imaging results were significantly improved with progressive COVID-19 treatment (P < 0.05).
Conclusion: The ultrasonic pulmonary imaging of COVID-19 patients manifested several characteristics. The modified Buda transthoracic pulmonary ultrasound protocol could be an alternative method to evaluate the pulmonary lesions in COVID-19 patients.

Although the outbreak in China has been effectively controlled, the international situation of prevention and control of coronavirus disease 2019 (COVID-19) still poses a serious public health risk. COVID-19 has been declared a pandemic by World Health Organization (WHO) due to its highly contagious nature, rapid transmission, swift clinical course, profound worldwide impact, and high mortality among critically ill patients. COVID-19 is mainly transmitted by respiratory droplets and contact routes, which could be effectively prevented by proper medical equipment and hand hygiene. However, due to the lack of effective protective measures and personal protective equipment of healthcare personnel in some area, the infectious rate of COVID-19 remains high, especially in clinical settings. At present, due to its portability and accuracy, ultrasound has been playing an indispensable role in the diagnosis, evaluation, and follow-up of COVID-19 patients, especially those in severe conditions. In the course of diagnosis and treatment, because sonographers often work closely with patients, coupled with the increasing number of patients and relatively poor ventilation in the working area, the risk of occupational exposure is undoubtedly high. This article combined the standard precaution methods with current Chinese government's COVID-19 strategy and polices, aiming to provide suggestions on the prevention and control of COVID-19 pandemic for ultrasound professionals.

Objective: The coronavirus disease (COVID-19) epidemic occurred suddenly, and had a severe impact on the whole society, especially the health care system. The purpose of this article is to share the experience of infection control management in the ultrasound department of China-Japan Friendship Hospital in response to the epidemic.
Methods: In accordance with relevant academic guidance and consensus guidelines, the ultrasound department followed principles of prevention and control which were promulgated by the hospital, combined management measures with the characteristics of ultrasound diagnosis and treatment, to control infection during the epidemic period. These measures included reducing the number of patients and doctors, using targeted protection standards in different work areas, and strengthening the training of staff in the department.
Results: During the epidemic in February to March 2020, the ultrasound department completed a total of 10,719 cases in the outpatient area (a decrease of 68.3% compared with the same period last year) and 1,583 cases from emergency (including 53 cases from the fever clinic). While the clinical needs were met, there was zero infection with COVID-19 of all health care staff in the ultrasound department during the epidemic.
Conclusions: We hope the valuable experience of infection control management in our ultrasound department in response to the epidemic can help global ultrasound doctors be prepared for the pandemic. The teams of ultrasound departments should also work closely with local infection control colleagues to implement measures that are appropriate for their own clinical settings to overcome the pandemic.

Objective: The aims of the current study were to describe the serial CT characteristics of patients infected with COVID-19. In addition, in the light of the CT findings, we tried to determine whether virulence weakens during the transmission with quarantine management.
Methods: Demographics, comorbidity, clinical findings, CT scanning, and scores of the affected lung parenchyma were compared for 131 patients with abnormality on CT images classified as COVID-19 pneumonia and the patients were divided between an imported group (n = 83) and indigenous group (n = 48), according to infected location. Two reviewers scored chest CT examinations for segmental involvement, ground glass opacities, consolidation, and honeycombing opacities. The 55 patients with peak CT "severity score" were selected o make a comparative analysis.
Results: Patients’ demographics and comorbidities and clinical findings did not differ significantly between the two groups. The CT scores distribution trendline of the third CT scanning was lower than the former CT scanning. The peak CT scores trendline of the 55 selected COVID-19 patients in the indigenous group was lower than the imported group. The ROC analysis revealed an area under curve of 0.714 for the CT scanning with an optimal cutoff scores of 2.55 for prediction of contact history, a sensitivity of 76.3%, and a specificity of 52.9%.The peak CT scores of the imported cases were higher than of the indigenous cases and the lung consolidation predominance on CT findings was remarkable in the imported patients (P < 0.05).
Conclusions: CT scanning not only monitored the progression of patients with COVID-19 but also reflected their exposure status to some extent. We suggest that a follow-up CT scanning interval of more than 5 days might be cost effective. The pathogenicity of novel coronavirus may be weakened through transmission under adequate quarantine measures, since indigenous cases have much better progression than imported cases.

Objective: To analyze the characteristics of bedside chest radiography in critically ill COVID-19 patients.
Methods: Bedside chest x-ray data of 8 severe cases with COVID-19 during hospitalization were collected consecutively. The disease was divided into three stages, including early stage (1-4 days), progression stage (5-10 days), and recovery stage(≥11 days). Two radiologists individually analyzed the chest radiographs by a double-blind method and compared the changes of the distribution, morphology, and boundary of the pulmonary lesions, as well as mediastinum and heart shadow of different disease stages.
Results: Among these cases, 1 case was in the early stage, 6 cases were in the progressive stage, and 1 case was in the recovery stage. A total of 68 bedside chest radiographs were obtained. In early stage, lesions were mainly in the external zone of both lungs with increased lamellar density. In progression stage, the lesions involved multiple pulmonary segments and lobes with extensive infiltrating changes. The heart shadow was mildly to moderately enlarged. In recovery stage, the broad distribution of striated density increased in both lungs, and the heart shadow remained enlarged.
Conclusions: The pulmonary lesions in critically ill COVID-19 patients were characterized by rapid progression, extensive distribution, varied manifestations, and possible concomitant cardiac dilatation. Bedside chest radiograph examination could provide certain significance in the follow-up of critically ill patients.

Objective: To explore the diagnostic value of pulmonary ultrasound in patients with coronavirus disease 2019 (COVID-19).
Methods: A total of 27 COVID-19 patients (mean age ± standard deviation, 62.6 ± 12.4 years) were enrolled in this study, including 14 males (51.9%) and 13 females (48.1%). Clinical information of these patients was collected, including age, gender, clinical manifestations, medical history, and laboratory indicators. All patients underwent ultrasound examination of their lungs and the results were analyzed.
Results: Ultrasound examination of the lungs showed that the lesions in 24 patients were located in both lungs (88.9%), 1 patient's lesions were located in the left lung (3.7%), and 2 patients' lesions were located in the right lung (7.4%). Patients with abnormal lung changes mainly had consolidation, air bronchogram, pisces sign, comet-tail artifact, pleural effusion, fusion B-line, and either multiple or few B-lines.
Conclusion: Pulmonary ultrasound examination was a convenient and radiation-free examination method, which could have important clinical value in evaluation of patients with COVID-19.

Objective: To determinate the clinicopathological characteristics of lung squamous cell carcinoma (SqCC), and investigate the correlation between these characteristics and quantitative parameters on spectral CT.
Methods: Institutional review board approval and informed consent were obtained. Eighty patients diagnosed with SqCC were enrolled. The clinicopathological characteristics were documented. The normalized iodine concentration (NIC) was measured. Differences of features between central and peripheral SqCCs were tested. Features associated with nodal involvement were analyzed. Differences of NIC with correlation of pathological results were examined.
Results: Of 80 patients, central SqCC was more frequently observed in patients who were younger (P = 0.013), presenting with vascular invasion (P = 0.022) and nodal metastases (P = 0.007), whereas stagedⅠdisease was more likely identified in peripheral SqCC (P = 0.019). The initial size (OR = 3.5, 95% CI: 1.3-9.2) and nerve invasion (OR = 5.6, 95% CI: 1.2-26.7) were significant independent factors of nodal involvement. Higher maximum NIC was significantly associated with increasing size of tumor (P < 0.001).
Conclusion: SqCC of the lung had distinct clinicopathological characteristics separately for tumors originated from central and peripheral areas. Initial size and nerve invasion were independent factors of nodal involvement. Higher iodine concentration was significantly associated with tumor growth.

Objective: To identify the characteristics and differences between type I and type II papillary renal cell carcinoma (PRCC) using ultrasound.
Methods: Twenty-five patients with PRCC, including 16 cases of type I and 9 cases of type II PRCC, were enrolled in this study. All lesions were surgically resected and pathologically confirmed. A conventional ultrasound and a contrast-enhanced ultrasound were performed on each of the 25 patients with PRCC before the operation. Both ultrasounds were performed by a single highlyqualified doctor with more than 10 years of experience. Features, including maximum diameter, boundary, shape, and growth pattern of the mass, color Doppler flow image (CDFI), enhancement pattern, degree, and uniformity, arrival time; and time to peak, obtained from the conventional and contrast-enhanced ultrasounds, were analyzed and compared between type I and type II PRCC.
Results: On conventional ultrasound, type II PRCCs were significantly larger (P = 0.000), less clear (P = 0.001) and more irregular (P = 0.004) than type I PRCCs. There was also a statistically significant difference in growth pattern (P = 0.019) and enhancement uniformity (P = 0.016) between type I and II PRCC.
Conclusion: There are statistically significant differences in sonographic features between the two types of PRCC. This knowledge could assist clinicians when choosing surgical procedures.

Objective: To evaluate the reliability of ultrasonographic (US) elastography of the sternocleidomastoid (SCM) muscle and to define normal strain ratio and shear wave velocity (SWV) values in healthy infants.
Methods: Two hundred healthy infants (mean age ± standard deviation, 1.64±1.78 month; 113 boys and 87 girls) were included in this prospective study. The thickness of bilateral SCM muscles was measured by B-mode ultrasonography, and the stiffness of SCM muscles was measured in both the longitudinal and transverse sections, symmetrical and extensional supine position, by using strain and shear wave elastography. The correlation between thickness and elastic values of the SCM muscle and the following possible influential factors were evaluated: sex, different sides of SCM muscle, different ultrasonic sections and different infant positions.
Results: Both sex and the side of SCM muscle did not show significant correlation with the thickness or stiffness of the SCM muscle (P > 0.05). The stiffness of SCM muscle in the longitudinal section was significantly greater than in the transverse section (P < 0.05). The measurements of the SCM muscle in the stretching position were significantly greater than those in the symmetrical position (P < 0.05).
Conclusion: The stiffness of SCM measured by US elastography is affected by relative positions of the infants. Therefore, the factor should be taken into account when measuring the stiffness of SCM by US elastography. US elastography can evaluate the stiffness of SCM, which is helpful for clinical diagnosis and treatment of children with torticollis.