A Rapid Adaptation Approach for Dynamic Air‑Writing Recognition Using Wearable Wristbands with Self‑Supervised Contrastive Learning

Wearable wristband systems leverage deep learning to revolutionize hand gesture recognition in daily activities.Unlike existing approaches that often focus on static gestures and require extensive labeled data,the proposed wearable wristband with selfsupervised contrastive learning excels at dynamic motion tracking and adapts rapidly across multiple scenarios.It features a four-channel sensing array composed of an ionic hydrogel with hierarchical microcone structures and ultrathin flexible electrodes,resulting in high-sensitivity capacitance output.Through wireless transmission from a Wi-Fi module,the proposed algorithm learns latent features from the unlabeled signals of random wrist movements.Remarkably,only few-shot labeled data are sufficient for fine-tuning the model,enabling rapid adaptation to various tasks.The system achieves a high accuracy of 94.9%in different scenarios,including the prediction of eight-direction commands,and air-writing of all numbers and letters.The proposed method facilitates smooth transitions between multiple tasks without the need for modifying the structure or undergoing extensive task-specific training.Its utility has been further extended to enhance human–machine interaction over digital platforms,such as game controls,calculators,and three-language login systems,offering users a natural and intuitive way of communication.

Right-to-left shunt detection via synchronized contrast transcranial Doppler combined with contrast transthoracic echocardiography:A preliminary study

BACKGROUND Patent foramen ovale(PFO)-related right-to-left shunts(RLSs)have been impli-cated in cryptogenic stroke and migraine,with larger shunts posing a higher risk.When used individually to detect RLS,contrast transcranial Doppler(cTCD)and contrast transthoracic echocardiography(cTTE)may yield false-negative results.Further,the literature exposes gaps regarding the understanding of the limitations of cTCD and cTTE,presents conflicting recommendations on their exclusive use,and highlights inefficiencies associated with nonsynchronous testing.AIM To investigate the accuracy of multimodal ultrasound to improve diagnostic efficiency in detecting PFO-related RLSs.METHODS We prospectively enrolled four patients with cryptogenic stroke(n=1),migraine(n=2),and unexplained dizziness(n=1)who underwent synchronized cTCD combined with cTTE.The participants were monitored and followed-up for 24 months.RESULTS cTTE identified moderate and large RLSs in patients with recurrent cryptogenic stroke and migraines,whereas cTCD revealed only small RLSs.Moderate and large RLS were confirmed on combined cTTE and cTCD.After excluding other causes,both patients underwent PFO occlusion.At 21-and 24-month follow-up examinations,neither stroke nor migraine had recurred.cTTE revealed a small RLS in a third patient with unexplained dizziness and a fourth patient with migraines;however,simultaneous cTCD detected a large RLS.These patients did not undergo interventional occlusion,and dizziness and headache recurred at the 17-and 24-month follow-up examin-ations.CONCLUSION Using cTTE or cTCD may underestimate RLS,impairing risk assessments.Combining synchronized cTCD with cTTE could enhance testing accuracy and support better diagnostic and therapeutic decisions.

Relationship of inflammatory indices with left atrial appendage thrombus or spontaneous echo contrast in patients with atrial fibrillation

BACKGROUND Inflammatory indices derived from complete blood tests have been reported to be associated with poor outcomes in patients with atrial fibrillation(AF).The data about the relationship between inflammatory indices and left atrial appendage thrombus(LAAT)or dense spontaneous echo contrast(SEC)are limited.AIM To explore the value of inflammatory indices for predicting the presence of LAAT or dense SEC in nonvalvular AF patients.METHODS A total of 406 patients with nonvalvular AF who underwent transesophageal echocardiography were included and divided into two groups based on the presence(study group)or absence(control group)of LAAT or dense SEC.Inflammatory indices,including the neutrophil-to-lymphocyte ratio(NLR),platelet–tolymphocyte ratio(PLR),and lymphocyte-to-monocyte ratio(LMR),were calculated from complete blood analysis.The associations of inflammatory indices RESULTS LAAT and dense SEC were detected in 11(2.7%)and 42(10.3%)patients,respectively.The PLR only showed an association with LAAT/dense SEC in the univariate model.Elevated NLR(odds ratio[OR]=1.48,95%confidence interval[CI]:1.11-1.98,P=0.007)and reduced LMR(OR=0.59,95%CI:0.41-0.83,P=0.003)were found to be independent risk factors for the presence of LAAT/dense SEC.The areas under the NLR and LMR curves for predicting LAAT/dense SEC were 0.73(95%CI:0.66-0.80,P<0.001)and 0.73(95%CI:0.65-0.81,P<0.001),respectively,while the cutoff values were 2.8(sensitivity:69.8%;specificity:64.0%)and 2.4(sensitivity:71.7%;specificity:60.6%),respectively.CONCLUSION Increased NLR and decreased LMR may predict LAAT/dense SEC in patients with nonvalvular AF.

Liver metastases:Contrast-enhanced ultrasound compared with computed tomography and magnetic resonance

The development of ultrasound contrast agents with excellent tolerance and safety profiles has notably improved liver evaluation with ultrasound(US)for several applications,especially for the detection of metastases.In particular,contrast enhanced ultrasonography(CEUS)allows the display of the parenchymal microvasculature,enabling the study and visualization of the enhancement patterns of liver lesions in real time and in a continuous manner in all vascular phases,which is similar to contrast-enhanced computed tomography(CT)and contrast-enhanced magnetic resonance imaging.Clinical studies have reported that the use of a contrast agent enables the visualization of more metastases with significantly improved sensitivity and specificity compared to baseline-US.Furthermore,studies have shown that CEUS yields sensitivities comparable to CT.In this review,we describe the state of the art of CEUS for detecting colorectal liver metastases,the imaging features,the literature reports of metastases in CEUS as well as its technique,its clinical role and its potential applications.Additionally,the updated international consensus panel guidelines are reported in this review with the inherent limitations of this technique and best practice experiences.

Value of contrast-enhanced intraoperative ultrasound for cirrhotic patients with hepatocellular carcinoma:A report of 20 cases

AIM： To assess the clinical value of contrast-enhanced intraoperative ultrasound （CE-IOUS） as a novel tool in partial hepatectomy for cirrhotic patients with hepatocellular carcinoma （HCC）. METHODS： From January 2007 to September 2007, a total of 20 consecutive cirrhotic patients with HCC scheduled to undergo partial hepatectomy were studied. Preoperative contrast enhanced computer tomography （CT） and/or magnetic resonance （MR） scans were performed within 1-2 wk before operation. Intraoperative ultrasound （IOUS） and CE-IOUS were carried out after mobilization of the liver. Lesions on precontrast and postcontrast scans were counted and mapped. CE-IOUS was performed with intravenous injection of ultrasound contrast agents SonoVue （Bracco Imaging, Milan, Italy）. Arterial, portal and late phases of contrast enhancement were recorded and analyzed. Nodules showing arterial phase hyper-enhancing and/or hypo-enhancing in late parenchymal phase were considered malignant and removed surgically. Ultrasound-guided biopsy and ethanol ablation would be an option if the nodule could not be removed surgically. Newly detected nodules on IOUS showing iso-enhancement in both arterial and late phases were considered benign. These nodules were either removed surgically if they were close to the main lesion or followed by examinations of alpha-fetoprotein （AFP） level and ultrasound and/or CT/MR every 3 too. RESULTS： IOUS found 41 nodules in total, among which 17 （41.46%） were newly detected compared to preoperative imaging. Thirty-three nodules were diagnosed malignant by CE-IOUS, including one missed by IOUS. The sensitivity and specificity of CE-IOUS on detecting HCC nodules are 100% （33/33 and 100% （9/9）, respectively. Nine nodules were considered benign by CE-IOUS, four was confirmed at histology and five by follow-up. CE-IOUS changed the surgical strategy in 35% （7/20） of patients and avoid unnecessary intervention in 30% （6/20） of patients. CONCLUSION： CE-IOUS is a useful means to characterize the nodules detected by IOUS in cirrhotic liver, to find isoechoic HCC nodules which can not be shown on IOUS and to improve the accuracy of conventional IOUS, thus it can be used as an essential tool in the surgical treatment of cirrhotic patients with HCC.

Evaluation of contrast-enhanced ultrasound for diagnosis of dysplastic nodules with a focus of hepatocellular carcinoma in liver cirrhosis patients

Objective： To compare the enhancement features of dysplastic nodnles with a focus of hepatocellular carcinoma （DN-HCC） versus HCC and regenerative nodules （RN） in cirrhotic patients. Methods： One hundred and ninety-three cirrhotic patients were enrolled in this study; they had 215 focal liver lesions, 1.0-3.5 cm in size, which were examined using contrast-enhanced ultrasound （CEUS） with SonoVue and diagnosed as HCC, RN or DN-HCC by biopsy. Samples were obtained using 18-gauge needles in the different enhanced areas. The enhancement features of DN-HCC, HCC and RN were evaluated. Results： There were 86 HCC lesions, 102 RN lesions, and 27 DN-HCC lesions diagnosed by biopsy. Of 86 HCC lesions, 87.2% （75/86） showed complete enhancement during the arterial phase, and 12.8% （11/86） had inhomogeneous enhancement, with no enhancement in the central area during the arterial phase; 100% （86/86） exhibited washout during the late phase. Of 102 RN lesions, 95.1% （97/102） had delayed or simultaneous enhancement during the arterial phase, and 4.9% （5/102） displayed slight enhancement during the arterial phase; 26.5% （27/102） exhibited washout and 73.5% （75/102） exhibited no washout during the late phase. In 27 DN-HCC lesions, only part of the lesions enhanced during the arterial phase and washed out during the late phase; the other areas had delayed or simultaneous enhancement during the arterial phase, and 29.6% （8/27） exhibited slight washout in the late phase. In 86 HCCs, the pathological feature was HCC in the enhanced area of 75 lesions, hepatocellular fatty degeneration in the slightly enhanced area of 7 lesions, and hepatocellular necrosis in the unenhanced area and HCC in the enhanced area of 4 lesions. In 102 RNs, the pathological diagnosis was hepatocyte proliferation with or without fatty degeneration. In 27 DN-HCCs, the pathological feature was HCC in the enhanced area and hepatocye regeneration in the unenhanced area. Conclusions： CEUS is useful for the diagnosis of focal liver lesions in cirrhotic patients. CEUS can help determine the progression from RN to DN-HCC to HCC by analyzing the hemodynamics. CEUS can promote the diagnostic accuracy of a biopsy by providing more accurate information on the site of the biopsy.

Multi-detector CT enterography with iso-osmotic mannitol as oral contrast for detecting small bowel disease

AIM: To assess the feasibility and usefulness of multi-detector CT enterography with orally administered iso-osmotic mannitol as negative contrast in demonstrating small bowel disease.METHODS: Thirteen volunteers and 38 patients with various kinds of small bowel disease were examined. We administered about 1 500 mL iso-osmotic mannitol as negative contrast agent and then proceeded with helical CT scanning on a Siemens Sensation 16 scanner. All volunteers and patients were interviewed about their tolerance of the procedure. Two radiologists postprocessed imaging data with MPR, thin MIP, VRT and INSPACE when necessary and then interpreted the scans,and adequacy of luminal distention was evaluated on a four-point scale. Demonstration of features of various kinds of small bowel disease was analyzed.RESULTS: The taste of iso-osmotic mannitol is good (slightly sweet) and acceptable by all. Small bowel distention was excellent and moderate in most volunteers and patients. CT features of many kinds of diseases such as tumors, Crohn's disease,and small bowel obstruction,etc. were clearly displayed.CONCLUSION: Multi-detector CT enterography with iso-osmotic mannitol as negative contrast to distend the small bowel is a simple, rapid, noninvasive and effective method of evaluating small bowel disease.

Contrast induced neurotoxicity following coronary angiogram with Iohexol in an end stage renal disease patient

Neurotoxicity is an infrequent adverse reaction to iodinated contrast agents. Contrast induced neurotoxicity following coronary angiogram is very rare. Renal disease is a risk factor for contrast induced neurotoxicity. We report a case of contrast induced neurotoxicity following coronary angiogram and intervention using Iohexol(Omnipaque 350) in an end stage renal disease patient on peritoneal dialysis who had prior exposure to iodinated contrast without any adverse reaction. Hemodialysis had to be initiated for rapid removal of the contrast agent with subsequent complete resolution of neurological deficits. This case highlights the need for interventionalists to be aware of an important adverse reaction to iodinated contrast agents, especially in individuals with renal dysfunction, and that neurotoxicity is a possibility even with prior uneventful exposures. The role and timing of hemodialysis in contrast induced neurotoxicity in patients with chronic kidney disease and in those without chronic kidney disease needs further deliberation.

Left atrial enlargement and non-paroxysmal atrial fibrillation as risk factors for left atrial thrombus/spontaneous Echo contrast in patients with atrial fibrillation and low CHA2DS2-VASc score

Objective To determine the risk factors for thromboembolism in lower risk patients with non-valvular atrial fibrillation(AF)and low CHA2DS2-VASc scores,which remain undefined.Methods We retrospectively analyzed the baseline clinical characteristics,routine laboratory parameters,and echocardiographic measurements of 705 patients(71.1%male;mean age:52.10±9.64 years)with low CHA2DS2-VASc score(0 or 1;1 point for female sex)out of 1346 consecutive patients with non-valvular AF who underwent transesophageal echocardiography(TEE)at Guangdong Cardiovascular Institute between January 2013 and December 2015.Results Patients with left atrial thrombus(LAT)or spontaneous echo contrast(SEC)on TEE(24/705,4%)showed a higher incidence rate of vascular disease(54.2%vs.32.9%,P=0.045)and non-paroxysmal AF(79.2%vs.29.4%,P<0.001),larger left atrial diameter(43.08±4.59 vs.36.02±5.53 mm,P<0.001),and lower left ventricular ejection fraction(58.23±8.82%vs.64.15±7.14%,P<0.001)than those without.Multivariate logistic regression analysis identified left atrial diameter[odds ratio(OR)=1.171,95%confidence interval(CI):1.084–1.265,P<0.001]and non-paroxysmal AF(OR=3.766,95%CI:1.282–11.061,P=0.016)as independent risk factors for LAT/SEC.In ROC curve analysis,a left atrial dimeter cutoff of 37.5 mm yielded 95.0%sensitivity and 62.7%specificity(AUC:0.847,P<0.0001,95%CI:0.793–0.914).Conclusion In patients with non-valvular AF with low CHA2DS2-VASc score,the presence of LAT or SEC was associated with left atrial enlargement,which had moderate predictive value,and non-paroxysmal AF.

“Wait and scan” management of patients with vestibular schwannoma and the relevance of non-contrast MRI in the follow-up

Vestibular schwannoma(VS) is a slow-growing benign neoplasm. There has been an evolution in the management of VS from active treatments(microsurgery and stereotactic radiotherapy) to conservative management(wait and scan). Regular MRI scanning is necessary to monitor tumor progression. Conservative management causes significantly less complications and offers a higher quality of life compared with active treatments. The mean growth rate of VS varies from 0.4 to 2.9 mm/year, and spontaneous shrinkage is observed in 3.8 percent of tumors during observation. If significant growth occurs, active treatment is considered. Significant growth is defined as an increase of at least 3 mm in the largest extrameatal diameter in any plane between the first and last available scans. The vestibulocochlear nerve is surrounded by cerebrospinal fluid, which provides natural contrast for MRI; thus, gadolinium may not be needed to detect VS. Specific sequences have high sensitivity, specificity, and accuracy for detection of progression. Hypointense signal in the ipsilateral inner ear fluid might be a useful sign to distinguish VS from meningioma. In this paper, we summarize the current status of research on conservative management and non-contrast MRI for the detection of VS.

Monitoring of renal ischemia reperfusion injury in rabbits by ultrasonic contrast and its relationship with expression of VEGF in renal tissue

Objective: To evaluate the renal ischemia reperfusion injury(IRI) in rabbits using the ultrasonic contrast technique and discuss the clinical value of ultrasonic contrast technique in the diagnosis of renal IRI by comparing the time-intensity curve of renal cortex and the expression of vascular endothelial growth factor(VEGF) of renal tissue. Methods: Twenty 3-month-old New Zealand rabbits were randomly divided into 4 groups, namely Ctrl group, IRI-12 h, IRI-24 h and IRI-48 h groups. The two dimensional gray-scale ultrasonography was employed to determine and mark the position of rabbit kidney. Rabbits were given the intraperitoneal anesthesia with 20% urethane with the dosage of 5 m L/kg. The aseptic operation was performed after the local skin disinfection in the area of both kidneys. The right kidney of animals in the control group was excised without any treatment for the left kidney. After excising the right kidney of animals in groups of IRI-12 h, IRI-24 h and IRI-48 h, the aneurysm clip was used to clip the renal pedicle vessel of left kidney, in order to simulate the ischemia. Because of the tissue ischemia, it could be seen that the color of kidney was changed from bright red to dark red, which indicated the successful modeling of ischemia. The aneurysm clip was released after one hour of maintaining the ischemia. Then the kidney turned out to be bright red from dark red, which indicated that the reperfusion was completed. Taking this moment as the time of ischemia reperfusion, the wound was stitched up. A total of 12, 24 and 36 h after the operation, the two-dimensional and color Doppler flow imaging and ultrasonic contrast were employed for the examination. The dynamic changes of ultrasonic contrast were recorded. The quantitative analysis software(Qontra Xt) was adopted to analyze the time-intensity curve of echo at different positions of renal cortex. After the ultrasonic contrast testing, rabbits were put to death. The renal cortex tissue was isolated and the tissue RNA and total protein were extracted respectively. Real-time PCR and western blotting were used to detect the VEGF and the Pearson product moment correlation coefficient was used to measure the linear relationship between these two variables. Results: The ultrasonic contrast could clearly reflect the process of IRI. The results of testing at m RNA and protein level indicated that the expression of VEGF in IRI groups was significantly increased(P<0.05) and the expression of VEGF was also increased by the time of reperfusion. Conclusions: There is the certain correlation between the expression of VEGF and process of IRI. The correlation coefficient between the ultrasonic contrast parameters of AT and TTP and the relative expression of VEGF is over 0.9, which indicates the relatively high correlation. But there is no significant difference in the change of perfusion peak intensity between groups, which has no correlation with the expression of VEGF.

Diagnosis of focal liver lesions with deep learning-based multichannel analysis of hepatocyte-specific contrast-enhanced magnetic resonance imaging

BACKGROUND The nature of input data is an essential factor when training neural networks.Research concerning magnetic resonance imaging(MRI)-based diagnosis of liver tumors using deep learning has been rapidly advancing.Still,evidence to support the utilization of multi-dimensional and multi-parametric image data is lacking.Due to higher information content,three-dimensional input should presumably result in higher classification precision.Also,the differentiation between focal liver lesions(FLLs)can only be plausible with simultaneous analysis of multisequence MRI images.AIM To compare diagnostic efficiency of two-dimensional(2D)and three-dimensional(3D)-densely connected convolutional neural networks(DenseNet)for FLLs on multi-sequence MRI.METHODS We retrospectively collected T2-weighted,gadoxetate disodium-enhanced arterial phase,portal venous phase,and hepatobiliary phase MRI scans from patients with focal nodular hyperplasia(FNH),hepatocellular carcinomas(HCC)or liver metastases(MET).Our search identified 71 FNH,69 HCC and 76 MET.After volume registration,the same three most representative axial slices from all sequences were combined into four-channel images to train the 2D-DenseNet264 network.Identical bounding boxes were selected on all scans and stacked into 4D volumes to train the 3D-DenseNet264 model.The test set consisted of 10-10-10 tumors.The performance of the models was compared using area under the receiver operating characteristic curve(AUROC),specificity,sensitivity,positive predictive values(PPV),negative predictive values(NPV),and f1 scores.RESULTS The average AUC value of the 2D model(0.98)was slightly higher than that of the 3D model(0.94).Mean PPV,sensitivity,NPV,specificity and f1 scores(0.94,0.93,0.97,0.97,and 0.93)of the 2D model were also superior to metrics of the 3D model(0.84,0.83,0.92,0.92,and 0.83).The classification metrics of FNH were 0.91,1.00,1.00,0.95,and 0.95 using the 2D and 0.90,0.90,0.95,0.95,and 0.90 using the 3D models.The 2D and 3D networks'performance in the diagnosis of HCC were 1.00,0.80,0.91,1.00,and 0.89 and 0.88,0.70,0.86,0.95,and 0.78,respectively;while the evaluation of MET lesions resulted in 0.91,1.00,1.00,0.95,and 0.95 and 0.75,0.90,0.94,0.85,and 0.82 using the 2D and 3D networks,respectively.CONCLUSION Both 2D and 3D-DenseNets can differentiate FNH,HCC and MET with good accuracy when trained on hepatocyte-specific contrast-enhanced multi-sequence MRI volumes.

Non-thermal ablation of rabbit liver VX2 tumor by pulsed high intensity focused ultrasound with ultrasound contrast agent:Pathological characteristics

AIM： To investigate the pathological characteristics of non-thermal damage induced by pulsed high intensity focused ultrasound （PHIFU） combined with ultrasound contrast agent （UCA）, SonoVue （Bracco SpA, Milan, Italy） in rabbit liver VX2 tumor. METHODS： Liver VX2 tumor models were established in 20 rabbits, which were divided randomly into PHIFU combined with ultrasound contrast agent group （PHIFU ＋ UCA group） and sham group. In the PHIFU ＋ UCA group, 0.2 mL of SonoVue was injected intravenously into the tumor, followed by ultrasound exposure of Isp 5900 W/cm^2. The rabbits were sacrificed one day after ultrasound exposure. Specimens of the exposed tumor tissues were obtained and observed pathologically under light microscope and transmission electron microscope. The remaining tumor tissues were sent for 2,3,5-Triphenyltetrazolium chloride （TTC） staining. RESULTS： Before Trc staining, tumor tissues in both the sham and the PHIFU ＋ UCA groups resembled gray fish meat, After TIC staining, the tumor tissues were uniformly stained red, with a clear boundary between tumor tissue and normal tissue, Histological examination showed signs of tumor cell injury in PHIFU ＋ UCA group, with cytoplasmic vacuoles of various sizes, chromatin margination and karyopyknosis. Electron microscopic examination revealed tumor cell volume reduction, karyopyknosis, chromatin margination, intercellular space widening, the presence of high electro＇n-density apoptotic bodies and vacuoles in cytoplasm. CONCLUSION： The non-thermal effects of PHIFU combined with UCA can be used to ablate rabbit liver VX2 tumors.

Contrast-enhanced ultrasound using SonoVue mixed with oral gastrointestinal contrast agent to evaluate esophageal hiatal hernia: Report of three cases and a literature review

BACKGROUND Due to a thicker abdominal wall in some patients,ultrasound artifacts from gastrointestinal gas and surrounding tissues can interfere with routine ultrasound examination,precluding its ability to display or clearly show the structure of a hernial sac(HS)and thereby diminishing diagnostic performance for esophageal hiatal hernia(EHH).Contrast-enhanced ultrasound(CEUS)imaging using an oral agent mixture allows for clear and intuitive identification of an EHH sac and dynamic observation of esophageal reflux.CASE SUMMARY In this case series,we report three patients with clinically-suspected EHH,including two females and one male with an average age of 67.3±16.4 years.CEUS was administered with an oral agent mixture(microbubble-based SonoVue and gastrointestinal contrast agent)and identified a direct sign of supradiaphragmatic HS(containing the hyperechoic agent)and indirect signs[e.g.,widening of esophageal hiatus,hyperechoic mixture agent continuously or intermittently reflux flowing back and forth from the stomach into the supradiaphragmatic HS,and esophagus-gastric echo ring(i.e.,the“EG”ring)seen above the diaphragm].All three cases received a definitive diagnosis of EHH by esophageal manometry and gastroscopy.Two lesions resolved upon drug treatment and one required surgery.The recurrence rate in follow-up was 0%.The data from these cases suggest that the new non-invasive examination method may greatly improve the diagnosis of EHH.CONCLUSION CEUS with the oral agent mixture can facilitate clear and intuitive identification of HS and dynamic observation of esophageal reflux.

Assessment of Myocardial Perfusion and Systolic Function in Patients with Coronary Artery Disease after Coronary Artery Bypass Surgery by Myocardial Contrast Echocardiography and Two-dimensional Strain Echocardiography

The clinically applied value of myocardial perfusion and systolic function in patients with coronary artery disease after coronary artery bypass surgery using real-time myocardial contrast echocardiography （RT-MCE） combined with two-dimensional strain echocardiography was assessed. Twenty patients underwent intravenous RT-MCE by intravenous injections of SonoVue before and after coronary artery bypass surgery. Two-dimensional images were recorded from the left ventricular four-chamber view, two-chamber view and the apical view before, and two weeks and three months after coronary artery bypass surgery, and the peak systolic longitudinal strain was measured. The results showed that myocardial perfusion was significantly increased after coronary artery bypass surgery in about 71.6% segments. In the group that myocardial perfusion was improved, the peak systolic longitu- dinal strain three months after bypass surgery was significantly higher than that before operation [（-15.78±5.91）% vs （-10.45±8.31）%, P〈0.05]. However, the parameters did not change in the group without myocardial perfusion improvement [（-10.33±6.53）% vs （-9.41±6.09）%, P〉0.05]. It was concluded that whether or not the improvement of myocardial perfusion can mirror the recovery trend of regional systolic function, two-dimensional strain echocardiography can observe dynamic change of regional systolic function. The combination of myocardial perfusion with two-dimensional strain echocardiography can more accurately assess the curative effectiveness of coronary artery bypass surgery.

Diagnosis of liver cirrhosis with contrast-enhanced ultrasound

The assessment of the extent of liver fibrosis is very important for the prognosis and clinical management of chronic liver diseases.Although liver biopsy is the gold standard for the assessment of liver fibrosis,new non-invasive diagnostic methods are urgently needed in clinical work due to certain limitations and complications of biopsy.Noninvasive imaging studies play an important role in the diagnosis of focal liver disease and diffuse liver diseases.Among them,ultrasonography is the first choice for study of the liver in clinical work.With the development of ultrasound contrast agents and contrast specific imaging techniques,contrastenhanced ultrasound(CEUS) shows good performance and great potential in the evaluation of liver fibrosis.Researchers have tried different kinds of contrast agent and imaging method,such as arrival time of contrast agent in the hepatic vein,and quantitative analysis of the enhancement level of liver parenchyma,to evaluate the degree of liver fibrosis during the past 10 years.This review mainly summarizes the clinical studies concerning the assessment of liver fibrosis using CEUS.

Predictive value of red cell distribution width on left atrial thrombus or left atrial spontaneous echo contrast in patients with non-valvular atrial fibrillation

Objective To evaluate the predictive value of red cell distribution width （RDW） on left atrial thrombus （LAT） or left atrial spontane- ous echo contrast （LASEC） in patients with non-valvular atrial fibrillation （AF）. Methods We reviewed 692 patients who were diagnosed as non-valvular AF and underwent transesophageal echocardiography （TEE） in Guangdong Cardiovascular Institute from April 2014 to December 2015. The baseline clinical characteristics, laboratory test of blood routine, electrocardiograph measurements were analyzed. Results Eighty-four patients were examined with LAT/LASEC under TEE. The mean RDW level was significantly higher in LAT/LASEC patients compared with the non-LAT/LASEC patients （13.59% ± 1.07% ws. 14.34% ± 1.34%; P 〈 0.001）. Receiver-operating characteristic curve analysis was performed and indicated the best RDW cut point was 13.16%. Furthermore, multivariate logistic regression analysis indicated that RDW level 〉 13.16% could be an independent risk factor for LAT/LASEC in patients with AF. Conclusion Elevated RDW level is associated with the presence of LAT/LASEC and could be with moderate predictive value for LAT/LASEC in patients with non-valvular AF.

Evaluation of Carotid Atherosclerotic Plaque Stability with Contrast-enhanced Ultrasonography

This study was aimed to evaluate the relationship between carotid atherosclerotic plaque stability and the clinical symptoms in patients with carotid atherosclerotic plaques by using contrast-enhanced ultrasonography. Fifty patients with carotid atherosclerotic plaques were enrolled and examined with contrast-enhanced ultrasonography. The correlation of contrast agent enhancement of the carotid atherosclerotic plaques and the clinical symptoms was analyzed. The results showed that among the 50 patients, plaques were enhanced in the 23 patients with obvious clinical symptoms. In 27 patients without apparent clinical symptoms, plaques were enhanced sparsely in 15 patients and not enhanced in 12 patients. It was suggested that contrast-enhanced ultrasonography could be used for the examination of the microcirculation in carotid atherosclerotic plaques on real-time basis and serve as a new noninvasive approach for the assessment of stability of carotid atherosclerotic plaques.

Comparison of contrast sensitivity and visual acuity between deep anterior lamellar keratoplasty and penetrating keratoplasty in patients with keratoconus

AIM: To evaluate postoperative visual acuity and contrast sensitivity results following deep anterior lamellar keratoplasty (DALK) and penetrating keratoplasty (PK) in patients with keratoconus (KC). METHODS: All the patients’ records with KC who had PK or DALK surgery between May 2010 and May 2011 were retrospectively reviewed. Sixty patients who underwent successful corneal transplantation for KC: 30 eyes underwent DALK and 30 eyes underwent PK were included in this study. Preoperative and postoperative mean logarithm of the minimum angle of resolution (logMAR) uncorrected visual acuity (UCVA), logMAR best spectacle-corrected visual acuity (BSCVA) and intraocular pressure (IOP) were evaluated. Contrast sensitivity tests (CS) were done preoperative and 2 months after all sutures had removed. All surgeries were performed under regional anesthesia (retrobulbar anesthesia) by 1 surgeon (B.K.) who was experienced in penetrating and lamellar keratoplasty techniques. RESULTS: The mean age of the DALK group was 29.67±4.95 (range 18-40) years and the PK group was 28.7±3.53 (range 18-39) years. Preoperatively there was no significant difference in the logMAR UCVA, logMAR BSCVA and IOP between the DALK (1.281±0.56; 0.97±0.85; 12.07±2.12mmHg) and PK (1.34±0.21; 0.98±0.21; 13±2.12mmHg) groups. One-year after surgery there was no significant difference in the mean logMAR UCVA and IOP between the DALK (0.46±0.37; 11.73±2.1mmHg) and PK (0.38±0.21; 12±2.12mmHg) groups. The mean contrast sensitivity was evaluated by CC-100 Topcon LCD at 1.5, 2.52, 4.23, 7.10 and 11.91 cycles per degree (cs/deg) spatial frequencies before and 2 months after the all sutures had removed. CONCLUSION: All patients with keratoconus in both DALK and PK groups performed good visual function postoperatively. The mean contrast sensitivity increased considerably at all spatial frequencies compared with preoperative levels in the DALK and PK groups. The mean post-operative evaluation of contrast sensitivity measurements was not significantly different between the two groups.

Android Malware Detection with Contrasting Permission Patterns

As the risk of malware is sharply increasing in Android platform,Android malware detection has become an important research topic.Existing works have demonstrated that required permissions of Android applications are valuable for malware analysis,but how to exploit those permission patterns for malware detection remains an open issue.In this paper,we introduce the contrasting permission patterns to characterize the essential differences between malwares and clean applications from the permission aspect Then a framework based on contrasting permission patterns is presented for Android malware detection.According to the proposed framework,an ensemble classifier,Enclamald,is further developed to detect whether an application is potentially malicious.Every contrasting permission pattern is acting as a weak classifier in Enclamald,and the weighted predictions of involved weak classifiers are aggregated to the final result.Experiments on real-world applications validate that the proposed Enclamald classifier outperforms commonly used classifiers for Android Malware Detection.