Acoustic radiation force(ARF), as an important particle manipulation method, has been extensively studied in recent years. With the introduction of the concept of “acoustic tweezers”, negative acoustic radiation has...Acoustic radiation force(ARF), as an important particle manipulation method, has been extensively studied in recent years. With the introduction of the concept of “acoustic tweezers”, negative acoustic radiation has become a research hotspot. In this paper, a scheme of realizing negative ARF based on the multiple-layered spherical structure design is proposed. The specific structure and design idea are presented. Detailed theoretical calculation analysis is carried out.Numerical simulations have been performed to verify the correctness of this prediction. The conjecture that the suppression of backscattering can achieve negative ARF is verified concretely, which greatly expands the application prospect and design ideas of the ARF. This work has laid a theoretical foundation for realizing precise control of the structure.展开更多
BACKGROUND Acoustic radiation force impulse(ARFI)is used to measure liver fibrosis and predict outcomes.The performance of elastography in assessment of fibrosis is poorer in hepatitis B virus(HBV)than in other etiolo...BACKGROUND Acoustic radiation force impulse(ARFI)is used to measure liver fibrosis and predict outcomes.The performance of elastography in assessment of fibrosis is poorer in hepatitis B virus(HBV)than in other etiologies of chronic liver disease.AIM To evaluate the performance of ARFI in long-term outcome prediction among different etiologies of chronic liver disease.METHODS Consecutive patients who received an ARFI study between 2011 and 2018 were enrolled.After excluding dual infection,alcoholism,autoimmune hepatitis,and others with incomplete data,this retrospective cohort were divided into hepatitis B(HBV,n=1064),hepatitis C(HCV,n=507),and non-HBV,non-HCV(NBNC,n=391)groups.The indexed cases were linked to cancer registration(1987-2020)and national mortality databases.The differences in morbidity and mortality among the groups were analyzed.RESULTS At the enrollment,the HBV group showed more males(77.5%),a higher prevalence of prediagnosed hepatocellular carcinoma(HCC),and a lower prevalence of comorbidities than the other groups(P<0.001).The HCV group was older and had a lower platelet count and higher ARFI score than the other groups(P<0.001).The NBNC group showed a higher body mass index and platelet count,a higher prevalence of pre-diagnosed non-HCC cancers(P<0.001),especially breast cancer,and a lower prevalence of cirrhosis.Male gender,ARFI score,and HBV were independent predictors of HCC.The 5-year risk of HCC was 5.9%and 9.8%for those ARFI-graded with severe fibrosis and cirrhosis.ARFI alone had an area under the receiver operating characteristic curve(AUROC)of 0.742 for prediction of HCC in 5 years.AUROC increased to 0.828 after adding etiology,gender,age,and platelet score.No difference was found in mortality rate among the groups.CONCLUSION The HBV group showed a higher prevalence of HCC but lower comorbidity that made mortality similar among the groups.Those patients with ARFI-graded severe fibrosis or cirrhosis should receive regular surveillance.展开更多
Expressions are derived for calculating the three-dimensional acoustic radiation force(ARF)on a multilayer microsphere positioned arbitrarily in a Gaussian beam.A theoretical model of a three-layer microsphere with a ...Expressions are derived for calculating the three-dimensional acoustic radiation force(ARF)on a multilayer microsphere positioned arbitrarily in a Gaussian beam.A theoretical model of a three-layer microsphere with a cell membrane,cytoplasm,and nucleus is established to study how particle geometry and position affect the three-dimensional ARF,and its results agree well with finite-element numerical results.The microsphere can be moved relative to the beam axis by changing its structure and position in the beam,and the axial ARF increases with increasing outer-shell thickness and core size.This study offers a theoretical foundation for selecting suitable parameters for manipulating a three-layer microsphere in a Gaussian beam.展开更多
Background:Porto-sinusoidal vascular disease(PSVD)and portal vein thrombosis(PVT)are causes of portal hypertension characterized respectively by an intrahepatic and a pre-hepatic obstacle to the flow in the portal sys...Background:Porto-sinusoidal vascular disease(PSVD)and portal vein thrombosis(PVT)are causes of portal hypertension characterized respectively by an intrahepatic and a pre-hepatic obstacle to the flow in the portal system.As PVT may be a consequence of PSVD,in PVT patients at presentation,a pre-existing PSVD should be suspected.In these patients the identification of an underlying PSVD would have relevant implication regarding follow-up and therapeutic management,but it could be challenging.In this setting ultrasonography may be valuable in differential diagnosis.The aim of the study was to use ultrasonography to identify parameters to discriminate between PSVD and“pure”PVT and then to suspect PVT secondary to a pre-existing PSVD.Methods:Fifty-three patients with histologically proven PSVD and forty-eight patients affected by chronic PVT were enrolled and submitted to abdominal ultrasonography with elastography by acoustic radiation force impulse(ARFI).Results:ARFI was higher and superior mesenteric vein(SMV)diameter was wider in PSVD patients than in PVT patients.Thus,a prognostic score was obtained as linear combinations of the two parameters with a good discrimination capacity between PSVD and PVT(the area under the curve=0.780;95%confidence interval:0.690-0.869).Conclusions:A score based on ARFI and SMV diameter may be useful to suspect an underlying PSVD in patients with PVT and to identify a subgroup of patients to be submitted to liver biopsy.展开更多
BACKGROUND: Acoustic radiation force impulse (ARFI) imaging is a new elastography method for the evaluation of tissue stiffness. This study aims to evaluate the performance of ARFI in noninvasive assessment of the tis...BACKGROUND: Acoustic radiation force impulse (ARFI) imaging is a new elastography method for the evaluation of tissue stiffness. This study aims to evaluate the performance of ARFI in noninvasive assessment of the tissue stiffness of focal liver lesion (FLL) and to explore its potential value in the differential diagnosis of FLL. METHODS: ARFI was performed in 140 patients with 154 FLLs, which included 28 hemangiomas (ANGIs), 14 focal nodular hyperplasias (FNHs), 61 hepatocellular carcinomas (HCCs), 39 metastases and 12 cholangiocellular carcinomas (CCCs). Virtual touch tissue quantification (VTTQ) values were obtained, analyzed and compared. The area under the receiver operating characteristic curve (AUROC) and optimal cut-off values were obtained using a receiver operating characteristic (ROC) curve analysis to assess diagnostic performance. All cases were definitively diagnosed using histopathology, CT, MRI or contrast-enhanced ultrasound. RESULTS: The VTTQ median values of ANGI, FNH, HCC metastasis and CCC were 1.30, 1.80, 2.52, 3.08 and 3.89 m/s respectively. A significant increase in the VTTQ values of different lesions was observed: ANGI【FNH【HCC【metastasis 【CCC (P【0.001). The AUROC (95% CI) of VTTQ values was 0.94 (0.90-0.98) for ANGI, 0.91 (0.87-0.96) for malignant lesions and 0.87 (0.79-0.94) for CCC. The sensitivity and specificity for ANGI (86.5%, 89.3%, respectively), malignancy (81.3% 92.9%, respectively), and CCC (91.7%, 72.5%, respectively) were associated with VTTQ cut-off values of 1.76, 2.22 and 3.00 m/s respectively.CONCLUSIONS: ARFI can accurately and objectively assess the elasticity of lesions by obtaining the shear wave elastic value of FLL with VTTQ. Therefore, ARFI is a novel, simple, noninvasive and useful diagnostic method for the characterization of FLL.展开更多
A modified Monte Carlo model of speckle tracking of shear wave propagation in scattering media is proposed. The established Monte Carlo model mainly concerns the variations of optical electric field and speckle. The t...A modified Monte Carlo model of speckle tracking of shear wave propagation in scattering media is proposed. The established Monte Carlo model mainly concerns the variations of optical electric field and speckle. The two- dimensional intensity distribution and the time evolution of speckles in different probe locations are obtained. The fluctuation of speckle intensity tracks the acoustic-radiation-force shear wave propagation, and especially the reduction of speckle intensity implies attenuation of shear wave. Then, the shear wave velocity is estimated quantitatively on the basis of the time-to-peak algorithm and linear regression processing. The results reveal that a smaller sampling interval yields higher estimation precision and the shear wave velocity is estimated more efficiently by using speckle intensity difference than by using speckle contrast difference according to the estimation error. Hence, the shear wave velocity is estimated to be 2.25 m/s with relatively high accuracy for the estimation error reaches the minimum (0.071).展开更多
We develop a model for calculating the radiation force on spherically symmetric multilayered particles based on the acoustic scattering approach. An expression is derived for the radiation force on a multilayered sphe...We develop a model for calculating the radiation force on spherically symmetric multilayered particles based on the acoustic scattering approach. An expression is derived for the radiation force on a multilayered sphere centered on the axis of a Gaussian standing wave propagating in an ideal fluid, The effects of the sound absorption of the materials and sound wave on acoustic radiation force of a multilayered sphere immersed in water are analyzed, with particular emphasis on the shell thickness of every layer, and the width of the Gaussian beam. The results reveal that the existence of particle trapping behavior depends on the choice of the non-dimensional frequency ka, as well as the shell thickness of each layer. This study provides a theoretical basis for the development of acoustical tweezers in a Gaussian standing wave, which may benefit the improvement and development of acoustic control technology, such as trapping, sorting, and assembling a cell, and drug delivery applications.展开更多
In this paper the elastic properties of SiOx film are investigated quantitatively for local fixed point and qualitatively for overall area by atomic force acoustic microscopy (AFAM) in which the sample is vibrated a...In this paper the elastic properties of SiOx film are investigated quantitatively for local fixed point and qualitatively for overall area by atomic force acoustic microscopy (AFAM) in which the sample is vibrated at the ultrasonic frequency while the sample surface is touched and scanned with the tip contacting the sample respectively for fixed point and continuous measurements. The SiOx films on the silicon wafers are prepared by the plasma enhanced chemical vapour deposition (PECVD), The local contact stiffness of the tip-SiOx film is calculated from the contact resonance spectrum measured with the atomic force acoustic microscopy. Using the reference approach, indentation modulus of SiOx film for fixed point is obtained. The images of cantilever amplitude are also visualized and analysed when the SiOx surface is excited at a fixed frequency. The results show that the acoustic amplitude images can reflect the elastic properties of the sample.展开更多
Acoustofluidic technology combines acoustic and microfluidic technologies to realize particle manipulation in microchannels driven by acoustic waves,and the acoustic radiation force(ARF)with boundaries is important fo...Acoustofluidic technology combines acoustic and microfluidic technologies to realize particle manipulation in microchannels driven by acoustic waves,and the acoustic radiation force(ARF)with boundaries is important for particle manipulation in an acoustofluidic device.In the work reported here,the ARF on a free cylinder immersed in a viscous fluid with an incident plane wave between two impedance boundaries is derived analytically and calculated numerically.The influence of multiple scattering between the particle and the impedance boundaries is described by means of image theory,the finite-series method,and the translational addition theorem,and multiple scattering is included partly in image theory.The ARF on a free rigid cylinder in a viscous fluid is analyzed by numerical calculation,with consideration given to the effects of the distances from cylinder edge to boundaries,fluid viscosity,cylinder size,and boundary reflectivity.The results show that the interaction between the two boundaries and the cylinder makes the ARF change more violently with different frequencies,while increasing the viscosity can reduce the amplitude of the ARF in boundary space.This study provides a theoretical basis for particle manipulation by the ARF in acoustofluidics.展开更多
Acoustic manipulation is one of the well-known technologies of particle control and a top research in acoustic field.Calculation of acoustic radiation force on a particle nearby boundaries is one of the critical tasks...Acoustic manipulation is one of the well-known technologies of particle control and a top research in acoustic field.Calculation of acoustic radiation force on a particle nearby boundaries is one of the critical tasks,as it approximates realistic applications.Nevertheless,it is quite difficult to solve the problem by theoretical method when the boundary conditions are intricate.In this study,we present a finite element method numerical model for the acoustic radiation force exerting on a rigid cylindrical particle immersed in fluid near a rigid corner.The effects of the boundaries on acoustic radiation force of a rigid cylinder are analyzed with particular emphasis on the non-dimensional frequency and the distance from the center of cylinder to each boundary.The results reveal that these parameters play important roles in acoustic manipulation for particle-nearby complicated rigid boundaries.This study verifies the feasibility of numerical analysis on the issue of acoustic radiation force calculation close to complex boundaries,which may provide a new idea on analyzing the acoustic particle manipulation in confined space.展开更多
Shell structures have increasingly widespread applications in biomedical ultrasound fields such as contrast agents and drug delivery,which requires the precise prediction of the acoustic radiation force under various ...Shell structures have increasingly widespread applications in biomedical ultrasound fields such as contrast agents and drug delivery,which requires the precise prediction of the acoustic radiation force under various circumstances to improve the system efficiency.The acoustic radiation force exerted by a zero-order quasi-Bessel-Gauss beam on an elastic spherical shell near an impedance boundary is theoretically and numerically studied in this study.By means of the finite series method and the image theory,a zero-order quasi-Bessel-Gauss beam is expanded in terms of spherical harmonic functions,and the exact solution of the acoustic radiation force is derived based on the acoustic scattering theory.The acoustic radiation force function,which represents the radiation force per unit energy density and per unit cross-sectional surface,is especially investigated.Some simulated results for a polymethyl methacrylate shell and an aluminum shell are provided to illustrate the behavior of acoustic radiation force in this case.The simulated results show the oscillatory property and the negative radiation force caused by the impedance boundary.An appropriate relative thickness of the shell can generate sharp peaks for a polymethyl methacrylate shell.Strong radiation force can be obtained at small half-cone angles and the beam waist only affects the results at high frequencies.Considering that the quasi-Bessel-Gauss beam possesses both the energy focusing property and the non-diffracting advantage,this study is expected to be useful in the development of acoustic tweezers,contrast agent micro-shells,and drug delivery applications.展开更多
Traditional technique such nanoindenter(NI) can't measure the local elastic modulus at nano-scale(lateral). Atomic force acoustic microscopy (AFAM) is a dynamic method, which can quantitatively determine indent...Traditional technique such nanoindenter(NI) can't measure the local elastic modulus at nano-scale(lateral). Atomic force acoustic microscopy (AFAM) is a dynamic method, which can quantitatively determine indentation modulus by measuring the contact resonance spectra for high order modes of the cantilever. But there are few reports on the effect of experimental factors, such length of cantilever, contact stiffness on measured value. For three different samples, including copper(Cu) film with 110 nm thickness, zinc(Zn) film of 90 nm thickness and glass slides, are prepared and tested, using referencing approach in which measurements are performed on the test and reference samples (it's elastic modulus is known), and their contact resonance spectra are measured used the AFAM system experimentally. According to the vibration theory, from the lowest two contact resonance frequencies, the tip-sample contact stiffness is calculated, and then the values for the elastic properties of test sample, such as the indentation modulus, are determined. Using AFAM system, the measured indentation modulus of copper nano-film, zinc nano-film and glass slides are 113.53 GPa, 87.92 GPa and 57.04 GPa, which are agreement with literature values Mcu--105-130 GPa, Mzn = 88.44 GPa and Molass = 50-90 GPa. Furthermore, the sensitivity of contact resonance frequency to contact stiffness is analyzed theoretically. The results show that for the cantilevers with the length 160 pm, 225 μm and 520 μm respectively, when contact stiffness increases from 400 N/m to 600 N/m, the increments of first contact resonance frequency are 126 kHz, 93 kHz and 0.6 kHz, which show that the sensitivity of the contact resonance frequency to the contact stiffness reduces with the length of cantilever increasing. The novel method presented can characterize elastic modulus of near surface for nano-film and bulk material, and local elasticity of near surface can be evaluated by optimizing the experimental parameters using the AFAM system.展开更多
Contactless manipulation of multi-scale objects using the acoustic vortex(AV) tweezers offers tremendous perspectives in biomedical applications.However,it is still hindered by the weak acoustic radiation force(ARF) a...Contactless manipulation of multi-scale objects using the acoustic vortex(AV) tweezers offers tremendous perspectives in biomedical applications.However,it is still hindered by the weak acoustic radiation force(ARF) and torque(ART)around the vortex center.By introducing the elevation angle to the planar transducers of an N-element ring array,the weakfocused acoustic vortex(WFAV) composed of a main-AV and N paraxial-AVs is constructed to conduct a large-scale object manipulation.Different from the traditional focused AV(FAV) generated by a ring array of concave spherical transducers,a much larger focal region of the WFAV is generated by the main lobes of the planar transducers with the size inversely associated with the elevation angle.With the pressure simulation of the acoustic field,the capability of the rotational object driving in the focal plane for the WFAV is analyzed using the ARF and the ART exerted on an elastic ball based on acoustic scattering.With the experimental system built in water,the generation of the WFAV is verified by the scanning measurements of the acoustic field and the capability of object manipulation is also analyzed by the rotational trapping of floating particles in the focal plane.The favorable results demonstrate the feasibility of large-scale rotational manipulation of objects with a strengthened ART and a reduced acousto-thermal damage to biological tissues,showing a promising prospect for potential applications in clinical practice.展开更多
Based on the angular spectrum decomposition and partial-wave series expansion methods, we investigate the radiation force functions of two Airy-Gaussian (AiG) beams on a cylindrical particle and the motion trajector...Based on the angular spectrum decomposition and partial-wave series expansion methods, we investigate the radiation force functions of two Airy-Gaussian (AiG) beams on a cylindrical particle and the motion trajectory of lhe particle. The simulations show that the particle can be pulled or propelled into either the positive or negative transverse direction by turning the phase difference between the two AiG beams appropriately; and the larger the beam widths of the two AiG beams are, the bigger the radiation force can be obtained to control the particle. In addition, the direction of the accelerated particle can be controlled while the dimensionless frequency bandwidth changes. The results indicate that the phase plays an important role in controlling the direction of the particle, which may provide a theoretical basis for the design of acoustical tweezers and the development of drug delivery.展开更多
To solve the difficulty of generating an ideal Bessel beam,an simplified annular transducer model is proposed to study the axial acoustic radiation force(ARF)and the corresponding negative ARF(pulling force)exerted on...To solve the difficulty of generating an ideal Bessel beam,an simplified annular transducer model is proposed to study the axial acoustic radiation force(ARF)and the corresponding negative ARF(pulling force)exerted on centered elastic spheres for acoustic-vortex(AV)beams of arbitrary orders.Based on the theory of acoustic scattering,the axial distributions of the velocity potential and the ARF for AV beams of different orders generated by the annular transducers with different physical sizes are simulated.It is proved that the pulling force can be generated by AV beams of arbitrary orders with multiple axial regions.The pulling force is more likely to exert on the sphere with a smaller k0a(product of the wave number and the radius)for the AV beam with a bigger topological charge due to the strengthened off-axis acoustic scattering.The pulling force decreases with the increase of the axial distance for the sphere with a bigger k0a.More pulling force areas with wider axial regions can be formed by AV beams using a bigger-sized annular transducer.The theoretical results demonstrate the feasibility of generating the pulling force along the axes of AV beams using the experimentally applicable circular array of planar transducers,and suggest application potentials for multi-position stable object manipulations in biomedical engineering.展开更多
Exact analytical equations and computations for the longitudinal and transverse acoustic radiation force and axial torque components for a lossless eccentric liquid cylinder submerged in a nonviscous fluid and insonif...Exact analytical equations and computations for the longitudinal and transverse acoustic radiation force and axial torque components for a lossless eccentric liquid cylinder submerged in a nonviscous fluid and insonified by plane waves progressive waves(of arbitrary incidence in the polar plane)are established and computed numerically.The modal matching method and the translational addition theorem in cylindrical coordinates are used to derive exact mathematical expressions applicable to any inner and outer cylinder sizes without any approximations,and taking into account the interaction effects between the waves propagating in the layer and those scattered from the cylindrical core.The results show that longitudinal and transverse radiation force components arise,in addition to the emergence of an axial radiation torque component acting on the non-absorptive compound cylinder due to geometrical asymmetry as the eccentricity increases.The computations demonstrate that the axial torque component,which arises due to a geometrical asymmetry,can be positive(causing counterclockwise rotation in the polar plane),negative(clockwise rotation)or neutral(rotation cancellation)depending on the size parameter of the cylinder and the amount of eccentricity.Furthermore,verification and validation of the results have been accomplished from the standpoint of energy conservation law applied to scattering,and based on the reciprocity theorem.展开更多
To evaluate the gastrocnemius/soleus and biceps brachii muscle stiffness by Acoustic Radiation Force Impulse (ARFI) elastography in the hemiplegia patients, sixty patients with hemiplegia after stroke were recruited. ...To evaluate the gastrocnemius/soleus and biceps brachii muscle stiffness by Acoustic Radiation Force Impulse (ARFI) elastography in the hemiplegia patients, sixty patients with hemiplegia after stroke were recruited. Baseline data were collected including age, gender, body mass index, education level, dominant side, affected side, time since stroke, stroke etiology. All patients were evaluated with before treatment and posttreatment with Broonstroom staging, Modified Ashworth spasticity scale, and Functional Independence Measures scale. The patient was divided into 3 groups: 1) Neuromuscular electrical stimulation group, 2) Rehabilitation group, 3) Neurumusculer electrical stimulation + Rehabilitation group. Affected and unaffected side biceps and gastrocnemius, ARFI elastography measurements were used to measure thickness and elastic values. In addition, before and after treatment, length and thickness were measured from all patients. Of the 60 subjects, 28 were female (46.7%) and 32 (53.3%) were males, with an average age of 58.42 ± 9.03 years. There was a significant difference between the upper and lower limbs after the treatment in terms of Brunstroom staging. In terms of Modified Ashworth scale, there was a significant difference in lower extremity only after treatment. When compared to the affected/unaffected side, before and after treatment, there was a significant difference in the measurements in both the medial gastrocnemius and the lateral gastrocnemius in all three groups. Further research with larger numbers of patients for longer periods is needed to clarify the relationship between the muscle hardness and degree of spasticity.展开更多
Objective:Acoustic radiation force impulse(ARFI)was applied to measure Shear wave velocity(SWV)of liver in patients with Wilson's disease(WD).To investigate the relationship between SWV and the serological indexes...Objective:Acoustic radiation force impulse(ARFI)was applied to measure Shear wave velocity(SWV)of liver in patients with Wilson's disease(WD).To investigate the relationship between SWV and the serological indexes of liver fibrosis,such as type Ⅳ collagen(CⅣ),hyaluronic acid(HA),type Ⅲ procollagen peptide(PⅢNP),laminin(LN),APRI score(Asparate Aminotransfer to Platelet Ratio Index),and FIB-4 index(FIB-4 index).The clinical efficacy of GandouTang(GDT)in the treatment of liver fibrosis in WD with damp-heat internalization was also observed.Methods:80 cases of WD patients who met the inclusion criteria were randomly divided into the treatment group and the control group,with 40 cases in each group.The control group was treated with Sodium Dimercaptopropylsulfonate(DMPS)and the treatment group was additionally treated with the traditional Chinese medicine GDT.One course for 8 days,a total of 6 courses.The levels of SwV and four serological indicators of liver fibrosis(PⅢNP,HA,CⅣ,LN),APRI score and FIB-4 index were compared before and after treatment.Pearson correlation test was used to analyze the correlation between SWV and HA,CⅣ,LN,PⅢNP,APRI score and FIB-4 index.The effects of GDT on SWV,liver fiber,APRI and FIB-4 were evaluated according to the treatment plan.Results:①The SWV was positively correlated with FIB-4(r=0.83),APRI(r=0.82),HA(r=0.87),CⅣ(r=0.71),LN(r=0.85)and PINP(r=0.77).②Before treatment,there were no significant differences in SWV level,PⅢNP,HA,CⅣ,LN,APRI and FIB-4 levels between two groups(P>0.05).After treatment,the levels of PⅢNP,HA,LN,SWV,APRI and FIB-4 in both groups were significantly decreased(P<0.05,P<0.01),and the levels in the treatment group were lower than those in the control group.There were no significant specific changes in CⅣ level(P>0.05).Conclusion:SWV value can reflect the degree of WD liver fibrosis,and is positively correlated with HA,PⅢNP,CⅣ,LN,FIB-4 index and APRI score.On the basis of the treatment of protecting liver and expelling copper with western medicine,plus the treatment of traditional Chinese medicine GDT can effectively improve the degree of liver fibrosis in WD patients with damp-heat accumulation.展开更多
AIM:To investigate whether a noninvasive measurement of tissue strain has a potential usefulness for management of nonalcoholic steatohepatitis(NASH).METHODS:In total 26 patients,23 NASHs and 3 normal controls were en...AIM:To investigate whether a noninvasive measurement of tissue strain has a potential usefulness for management of nonalcoholic steatohepatitis(NASH).METHODS:In total 26 patients,23 NASHs and 3 normal controls were enrolled in this study.NASH was staged based on Brunt criterion.At a region of interest(ROI),a shear wave was evoked by implementing an acoustic radiation force impulse(ARFI),and the propagation velocity was quantif ied.RESULTS:Shear wave velocity(SWV) could be reproducibly quantified at all ROIs in all subjects except for 4 NASH cases,in which a reliable SWV value was not calculated at several ROIs.An average SWV of 1.34 ± 0.26 m/s in fibrous stage 0-1 was significantly slower than 2.20 ± 0.74 m/s and 2.90 ± 1.01 m/s in stages 3 and 4,respectively,but was not significantly different from 1.79 ± 0.78 m/s in stage 2.When a cutoff value was set at 1.47 m/s,receiver operating characteristic analysis showed significance to dissociate stages 3 and 4 from stage 0-1(P=0.0092) with sensitivity,specificity and area under curve of 100%,75% and 94.2%,respectively.In addition,the correlation between SWV and hyaluronic acid was significant(P<0.0001),while a tendency toward negative correlation was observed with serum albumin(P=0.053).CONCLUSION:The clinical implementation of ARFI provides noninvasive repeated evaluations of liver stiffness at an arbitrary position,which has the potential to shed new light on NASH management.展开更多
Progressive fibrosis is encountered in almost all chronicliver diseases. Its clinical signs are diagnostic in advanced cirrhosis, but compensated liver cirrhosis is harder to diagnose. Liver biopsy is still considered...Progressive fibrosis is encountered in almost all chronicliver diseases. Its clinical signs are diagnostic in advanced cirrhosis, but compensated liver cirrhosis is harder to diagnose. Liver biopsy is still considered the reference method for staging the severity of fibrosis, but due to its drawbacks(inter and intra-observer variability, sampling errors, unequal distribution of fibrosis in the liver, and risk of complications and even death), non-invasive methods were developed to assess fibrosis(serologic and elastographic). Elastographic methods can be ultrasound-based or magnetic resonance imaging-based. All ultrasoundbased elastographic methods are valuable for the early diagnosis of cirrhosis, especially transient elastography(TE) and acoustic radiation force impulse(ARFI) elastography, which have similar sensitivities and specificities, although ARFI has better feasibility. TE is a promising method for predicting portal hypertension in cirrhotic patients, but it cannot replace upper digestive endoscopy. The diagnostic accuracy of using ARFI in the liver to predict portal hypertension in cirrhotic patients is debatable, with controversial results in published studies. The accuracy of ARFI elastography may be significantly increased if spleen stiffness is assessed, either alone or in combination with liver stiffness and other parameters. Two-dimensional shearwave elastography, the Elast PQ technique and strain elastography all need to be evaluated as predictors of portal hypertension.展开更多
基金Project supported by the National Key Research and Development Program of China (Grant No.2020YFA0211400)the State Key Program of the National Natural Science Foundation of China (Grant No.11834008)+3 种基金the National Natural Science Foundation of China (Grant Nos.12174192 and 12204119)the Fund from the State Key Laboratory of Acoustics,Chinese Academy of Sciences (Grant No.SKLA202210)the Fund from the Key Laboratory of Underwater Acoustic Environment,Chinese Academy of Sciences (Grant No.SSHJ-KFKT-1701)the Science and Technology Foundation of Guizhou Province,China (Grant No.ZK[2023]249)。
文摘Acoustic radiation force(ARF), as an important particle manipulation method, has been extensively studied in recent years. With the introduction of the concept of “acoustic tweezers”, negative acoustic radiation has become a research hotspot. In this paper, a scheme of realizing negative ARF based on the multiple-layered spherical structure design is proposed. The specific structure and design idea are presented. Detailed theoretical calculation analysis is carried out.Numerical simulations have been performed to verify the correctness of this prediction. The conjecture that the suppression of backscattering can achieve negative ARF is verified concretely, which greatly expands the application prospect and design ideas of the ARF. This work has laid a theoretical foundation for realizing precise control of the structure.
基金Supported by the Chang Gung Memorial Hospital and PAII Inc.(a United States subsidiary company of Ping An Insurance Group),No.SMRPG3I0011.
文摘BACKGROUND Acoustic radiation force impulse(ARFI)is used to measure liver fibrosis and predict outcomes.The performance of elastography in assessment of fibrosis is poorer in hepatitis B virus(HBV)than in other etiologies of chronic liver disease.AIM To evaluate the performance of ARFI in long-term outcome prediction among different etiologies of chronic liver disease.METHODS Consecutive patients who received an ARFI study between 2011 and 2018 were enrolled.After excluding dual infection,alcoholism,autoimmune hepatitis,and others with incomplete data,this retrospective cohort were divided into hepatitis B(HBV,n=1064),hepatitis C(HCV,n=507),and non-HBV,non-HCV(NBNC,n=391)groups.The indexed cases were linked to cancer registration(1987-2020)and national mortality databases.The differences in morbidity and mortality among the groups were analyzed.RESULTS At the enrollment,the HBV group showed more males(77.5%),a higher prevalence of prediagnosed hepatocellular carcinoma(HCC),and a lower prevalence of comorbidities than the other groups(P<0.001).The HCV group was older and had a lower platelet count and higher ARFI score than the other groups(P<0.001).The NBNC group showed a higher body mass index and platelet count,a higher prevalence of pre-diagnosed non-HCC cancers(P<0.001),especially breast cancer,and a lower prevalence of cirrhosis.Male gender,ARFI score,and HBV were independent predictors of HCC.The 5-year risk of HCC was 5.9%and 9.8%for those ARFI-graded with severe fibrosis and cirrhosis.ARFI alone had an area under the receiver operating characteristic curve(AUROC)of 0.742 for prediction of HCC in 5 years.AUROC increased to 0.828 after adding etiology,gender,age,and platelet score.No difference was found in mortality rate among the groups.CONCLUSION The HBV group showed a higher prevalence of HCC but lower comorbidity that made mortality similar among the groups.Those patients with ARFI-graded severe fibrosis or cirrhosis should receive regular surveillance.
基金supported by the National Natural Science Foundation of China (Grant No.11874252)the Fundamental Research Funds for the Central Universities (Grant No.2020TS029).
文摘Expressions are derived for calculating the three-dimensional acoustic radiation force(ARF)on a multilayer microsphere positioned arbitrarily in a Gaussian beam.A theoretical model of a three-layer microsphere with a cell membrane,cytoplasm,and nucleus is established to study how particle geometry and position affect the three-dimensional ARF,and its results agree well with finite-element numerical results.The microsphere can be moved relative to the beam axis by changing its structure and position in the beam,and the axial ARF increases with increasing outer-shell thickness and core size.This study offers a theoretical foundation for selecting suitable parameters for manipulating a three-layer microsphere in a Gaussian beam.
基金This study was approved by Ethical Committee of The Sapienza University of Rome(5068/2018).
文摘Background:Porto-sinusoidal vascular disease(PSVD)and portal vein thrombosis(PVT)are causes of portal hypertension characterized respectively by an intrahepatic and a pre-hepatic obstacle to the flow in the portal system.As PVT may be a consequence of PSVD,in PVT patients at presentation,a pre-existing PSVD should be suspected.In these patients the identification of an underlying PSVD would have relevant implication regarding follow-up and therapeutic management,but it could be challenging.In this setting ultrasonography may be valuable in differential diagnosis.The aim of the study was to use ultrasonography to identify parameters to discriminate between PSVD and“pure”PVT and then to suspect PVT secondary to a pre-existing PSVD.Methods:Fifty-three patients with histologically proven PSVD and forty-eight patients affected by chronic PVT were enrolled and submitted to abdominal ultrasonography with elastography by acoustic radiation force impulse(ARFI).Results:ARFI was higher and superior mesenteric vein(SMV)diameter was wider in PSVD patients than in PVT patients.Thus,a prognostic score was obtained as linear combinations of the two parameters with a good discrimination capacity between PSVD and PVT(the area under the curve=0.780;95%confidence interval:0.690-0.869).Conclusions:A score based on ARFI and SMV diameter may be useful to suspect an underlying PSVD in patients with PVT and to identify a subgroup of patients to be submitted to liver biopsy.
文摘BACKGROUND: Acoustic radiation force impulse (ARFI) imaging is a new elastography method for the evaluation of tissue stiffness. This study aims to evaluate the performance of ARFI in noninvasive assessment of the tissue stiffness of focal liver lesion (FLL) and to explore its potential value in the differential diagnosis of FLL. METHODS: ARFI was performed in 140 patients with 154 FLLs, which included 28 hemangiomas (ANGIs), 14 focal nodular hyperplasias (FNHs), 61 hepatocellular carcinomas (HCCs), 39 metastases and 12 cholangiocellular carcinomas (CCCs). Virtual touch tissue quantification (VTTQ) values were obtained, analyzed and compared. The area under the receiver operating characteristic curve (AUROC) and optimal cut-off values were obtained using a receiver operating characteristic (ROC) curve analysis to assess diagnostic performance. All cases were definitively diagnosed using histopathology, CT, MRI or contrast-enhanced ultrasound. RESULTS: The VTTQ median values of ANGI, FNH, HCC metastasis and CCC were 1.30, 1.80, 2.52, 3.08 and 3.89 m/s respectively. A significant increase in the VTTQ values of different lesions was observed: ANGI【FNH【HCC【metastasis 【CCC (P【0.001). The AUROC (95% CI) of VTTQ values was 0.94 (0.90-0.98) for ANGI, 0.91 (0.87-0.96) for malignant lesions and 0.87 (0.79-0.94) for CCC. The sensitivity and specificity for ANGI (86.5%, 89.3%, respectively), malignancy (81.3% 92.9%, respectively), and CCC (91.7%, 72.5%, respectively) were associated with VTTQ cut-off values of 1.76, 2.22 and 3.00 m/s respectively.CONCLUSIONS: ARFI can accurately and objectively assess the elasticity of lesions by obtaining the shear wave elastic value of FLL with VTTQ. Therefore, ARFI is a novel, simple, noninvasive and useful diagnostic method for the characterization of FLL.
基金Supported by the National Key Scientific Instrument and Equipment Development Projects of China under Grant No 81127901the National Natural Science Foundation of China under Grant Nos 61372017 and 30970828
文摘A modified Monte Carlo model of speckle tracking of shear wave propagation in scattering media is proposed. The established Monte Carlo model mainly concerns the variations of optical electric field and speckle. The two- dimensional intensity distribution and the time evolution of speckles in different probe locations are obtained. The fluctuation of speckle intensity tracks the acoustic-radiation-force shear wave propagation, and especially the reduction of speckle intensity implies attenuation of shear wave. Then, the shear wave velocity is estimated quantitatively on the basis of the time-to-peak algorithm and linear regression processing. The results reveal that a smaller sampling interval yields higher estimation precision and the shear wave velocity is estimated more efficiently by using speckle intensity difference than by using speckle contrast difference according to the estimation error. Hence, the shear wave velocity is estimated to be 2.25 m/s with relatively high accuracy for the estimation error reaches the minimum (0.071).
基金Project supported by National Key R&D Program of China(Grant No.2016YFF0203000)the National Natural Science Foundation of China(Grant Nos.11774167 and 61571222)+2 种基金the Fundamental Research Funds for the Central Universities of China(Grant No.020414380001)the Key Laboratory of Underwater Acoustic Environment,Institute of Acoustics,Chinese Academy of Sciences(Grant No.SSHJ-KFKT-1701)the AQSIQ Technology R&D Program of China(Grant No.2017QK125)
文摘We develop a model for calculating the radiation force on spherically symmetric multilayered particles based on the acoustic scattering approach. An expression is derived for the radiation force on a multilayered sphere centered on the axis of a Gaussian standing wave propagating in an ideal fluid, The effects of the sound absorption of the materials and sound wave on acoustic radiation force of a multilayered sphere immersed in water are analyzed, with particular emphasis on the shell thickness of every layer, and the width of the Gaussian beam. The results reveal that the existence of particle trapping behavior depends on the choice of the non-dimensional frequency ka, as well as the shell thickness of each layer. This study provides a theoretical basis for the development of acoustical tweezers in a Gaussian standing wave, which may benefit the improvement and development of acoustic control technology, such as trapping, sorting, and assembling a cell, and drug delivery applications.
基金Project supported by the National Natural Science Foundation of China(Grant No.50775005)
文摘In this paper the elastic properties of SiOx film are investigated quantitatively for local fixed point and qualitatively for overall area by atomic force acoustic microscopy (AFAM) in which the sample is vibrated at the ultrasonic frequency while the sample surface is touched and scanned with the tip contacting the sample respectively for fixed point and continuous measurements. The SiOx films on the silicon wafers are prepared by the plasma enhanced chemical vapour deposition (PECVD), The local contact stiffness of the tip-SiOx film is calculated from the contact resonance spectrum measured with the atomic force acoustic microscopy. Using the reference approach, indentation modulus of SiOx film for fixed point is obtained. The images of cantilever amplitude are also visualized and analysed when the SiOx surface is excited at a fixed frequency. The results show that the acoustic amplitude images can reflect the elastic properties of the sample.
基金This work was supported by the National Key R&D Program of China(Grant No.2020YFA0211400)the State Key Program of the National Natural Science Foundation of China(Grant No.11834008)+2 种基金the National Natural Science Foundation of China(Grant Nos.12174192 and 11774167)the State Key Laboratory of Acoustics,Chinese Academy of Science(Grant No.SKLA202210)the Key Laboratory of Underwater Acoustic Environment,Chinese Academy of Sciences(Grant No.SSHJ-KFKT-1701).
文摘Acoustofluidic technology combines acoustic and microfluidic technologies to realize particle manipulation in microchannels driven by acoustic waves,and the acoustic radiation force(ARF)with boundaries is important for particle manipulation in an acoustofluidic device.In the work reported here,the ARF on a free cylinder immersed in a viscous fluid with an incident plane wave between two impedance boundaries is derived analytically and calculated numerically.The influence of multiple scattering between the particle and the impedance boundaries is described by means of image theory,the finite-series method,and the translational addition theorem,and multiple scattering is included partly in image theory.The ARF on a free rigid cylinder in a viscous fluid is analyzed by numerical calculation,with consideration given to the effects of the distances from cylinder edge to boundaries,fluid viscosity,cylinder size,and boundary reflectivity.The results show that the interaction between the two boundaries and the cylinder makes the ARF change more violently with different frequencies,while increasing the viscosity can reduce the amplitude of the ARF in boundary space.This study provides a theoretical basis for particle manipulation by the ARF in acoustofluidics.
基金supported by the National Natural Science Foundation of China(Grant Nos.11604361 and 11904384)the National Key R&D Program of China(Grant No.2018 YFC0114900)Youth Innovation Promotion Association,Chinese Academy of Sciences(Grant No.2019024)。
文摘Acoustic manipulation is one of the well-known technologies of particle control and a top research in acoustic field.Calculation of acoustic radiation force on a particle nearby boundaries is one of the critical tasks,as it approximates realistic applications.Nevertheless,it is quite difficult to solve the problem by theoretical method when the boundary conditions are intricate.In this study,we present a finite element method numerical model for the acoustic radiation force exerting on a rigid cylindrical particle immersed in fluid near a rigid corner.The effects of the boundaries on acoustic radiation force of a rigid cylinder are analyzed with particular emphasis on the non-dimensional frequency and the distance from the center of cylinder to each boundary.The results reveal that these parameters play important roles in acoustic manipulation for particle-nearby complicated rigid boundaries.This study verifies the feasibility of numerical analysis on the issue of acoustic radiation force calculation close to complex boundaries,which may provide a new idea on analyzing the acoustic particle manipulation in confined space.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.81527901,11604361,and 91630309)。
文摘Shell structures have increasingly widespread applications in biomedical ultrasound fields such as contrast agents and drug delivery,which requires the precise prediction of the acoustic radiation force under various circumstances to improve the system efficiency.The acoustic radiation force exerted by a zero-order quasi-Bessel-Gauss beam on an elastic spherical shell near an impedance boundary is theoretically and numerically studied in this study.By means of the finite series method and the image theory,a zero-order quasi-Bessel-Gauss beam is expanded in terms of spherical harmonic functions,and the exact solution of the acoustic radiation force is derived based on the acoustic scattering theory.The acoustic radiation force function,which represents the radiation force per unit energy density and per unit cross-sectional surface,is especially investigated.Some simulated results for a polymethyl methacrylate shell and an aluminum shell are provided to illustrate the behavior of acoustic radiation force in this case.The simulated results show the oscillatory property and the negative radiation force caused by the impedance boundary.An appropriate relative thickness of the shell can generate sharp peaks for a polymethyl methacrylate shell.Strong radiation force can be obtained at small half-cone angles and the beam waist only affects the results at high frequencies.Considering that the quasi-Bessel-Gauss beam possesses both the energy focusing property and the non-diffracting advantage,this study is expected to be useful in the development of acoustic tweezers,contrast agent micro-shells,and drug delivery applications.
基金supported by National Natural Science Foundation of China(Grant No. 50775005)General Program of Science and Technology Development Project of Beijing Municipal Education Commission(Grant No. KM201110015009)
文摘Traditional technique such nanoindenter(NI) can't measure the local elastic modulus at nano-scale(lateral). Atomic force acoustic microscopy (AFAM) is a dynamic method, which can quantitatively determine indentation modulus by measuring the contact resonance spectra for high order modes of the cantilever. But there are few reports on the effect of experimental factors, such length of cantilever, contact stiffness on measured value. For three different samples, including copper(Cu) film with 110 nm thickness, zinc(Zn) film of 90 nm thickness and glass slides, are prepared and tested, using referencing approach in which measurements are performed on the test and reference samples (it's elastic modulus is known), and their contact resonance spectra are measured used the AFAM system experimentally. According to the vibration theory, from the lowest two contact resonance frequencies, the tip-sample contact stiffness is calculated, and then the values for the elastic properties of test sample, such as the indentation modulus, are determined. Using AFAM system, the measured indentation modulus of copper nano-film, zinc nano-film and glass slides are 113.53 GPa, 87.92 GPa and 57.04 GPa, which are agreement with literature values Mcu--105-130 GPa, Mzn = 88.44 GPa and Molass = 50-90 GPa. Furthermore, the sensitivity of contact resonance frequency to contact stiffness is analyzed theoretically. The results show that for the cantilevers with the length 160 pm, 225 μm and 520 μm respectively, when contact stiffness increases from 400 N/m to 600 N/m, the increments of first contact resonance frequency are 126 kHz, 93 kHz and 0.6 kHz, which show that the sensitivity of the contact resonance frequency to the contact stiffness reduces with the length of cantilever increasing. The novel method presented can characterize elastic modulus of near surface for nano-film and bulk material, and local elasticity of near surface can be evaluated by optimizing the experimental parameters using the AFAM system.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11934009,11974187,and 12004187)the Natural Science Foundation of Jiangsu Province,China(Grant Nos.BK20161013 and BK20200724)。
文摘Contactless manipulation of multi-scale objects using the acoustic vortex(AV) tweezers offers tremendous perspectives in biomedical applications.However,it is still hindered by the weak acoustic radiation force(ARF) and torque(ART)around the vortex center.By introducing the elevation angle to the planar transducers of an N-element ring array,the weakfocused acoustic vortex(WFAV) composed of a main-AV and N paraxial-AVs is constructed to conduct a large-scale object manipulation.Different from the traditional focused AV(FAV) generated by a ring array of concave spherical transducers,a much larger focal region of the WFAV is generated by the main lobes of the planar transducers with the size inversely associated with the elevation angle.With the pressure simulation of the acoustic field,the capability of the rotational object driving in the focal plane for the WFAV is analyzed using the ARF and the ART exerted on an elastic ball based on acoustic scattering.With the experimental system built in water,the generation of the WFAV is verified by the scanning measurements of the acoustic field and the capability of object manipulation is also analyzed by the rotational trapping of floating particles in the focal plane.The favorable results demonstrate the feasibility of large-scale rotational manipulation of objects with a strengthened ART and a reduced acousto-thermal damage to biological tissues,showing a promising prospect for potential applications in clinical practice.
基金Project supported by the National Key R&D Program,China(Grant No.2016YFF0203000)the National Natural Science Foundation of China(Grant Nos.11774167 and 61571222)+2 种基金Fundamental Research Funds for the Central Universities,China(Grant No.020414380001)State Key Laboratory of Acoustics,Chinese Academy of Sciences(Grant No.SKLA201609)AQSIQ Technology R&D Program,China(Grant No.2017QK125)
文摘Based on the angular spectrum decomposition and partial-wave series expansion methods, we investigate the radiation force functions of two Airy-Gaussian (AiG) beams on a cylindrical particle and the motion trajectory of lhe particle. The simulations show that the particle can be pulled or propelled into either the positive or negative transverse direction by turning the phase difference between the two AiG beams appropriately; and the larger the beam widths of the two AiG beams are, the bigger the radiation force can be obtained to control the particle. In addition, the direction of the accelerated particle can be controlled while the dimensionless frequency bandwidth changes. The results indicate that the phase plays an important role in controlling the direction of the particle, which may provide a theoretical basis for the design of acoustical tweezers and the development of drug delivery.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11934009,11974187,and 11604156).
文摘To solve the difficulty of generating an ideal Bessel beam,an simplified annular transducer model is proposed to study the axial acoustic radiation force(ARF)and the corresponding negative ARF(pulling force)exerted on centered elastic spheres for acoustic-vortex(AV)beams of arbitrary orders.Based on the theory of acoustic scattering,the axial distributions of the velocity potential and the ARF for AV beams of different orders generated by the annular transducers with different physical sizes are simulated.It is proved that the pulling force can be generated by AV beams of arbitrary orders with multiple axial regions.The pulling force is more likely to exert on the sphere with a smaller k0a(product of the wave number and the radius)for the AV beam with a bigger topological charge due to the strengthened off-axis acoustic scattering.The pulling force decreases with the increase of the axial distance for the sphere with a bigger k0a.More pulling force areas with wider axial regions can be formed by AV beams using a bigger-sized annular transducer.The theoretical results demonstrate the feasibility of generating the pulling force along the axes of AV beams using the experimentally applicable circular array of planar transducers,and suggest application potentials for multi-position stable object manipulations in biomedical engineering.
文摘Exact analytical equations and computations for the longitudinal and transverse acoustic radiation force and axial torque components for a lossless eccentric liquid cylinder submerged in a nonviscous fluid and insonified by plane waves progressive waves(of arbitrary incidence in the polar plane)are established and computed numerically.The modal matching method and the translational addition theorem in cylindrical coordinates are used to derive exact mathematical expressions applicable to any inner and outer cylinder sizes without any approximations,and taking into account the interaction effects between the waves propagating in the layer and those scattered from the cylindrical core.The results show that longitudinal and transverse radiation force components arise,in addition to the emergence of an axial radiation torque component acting on the non-absorptive compound cylinder due to geometrical asymmetry as the eccentricity increases.The computations demonstrate that the axial torque component,which arises due to a geometrical asymmetry,can be positive(causing counterclockwise rotation in the polar plane),negative(clockwise rotation)or neutral(rotation cancellation)depending on the size parameter of the cylinder and the amount of eccentricity.Furthermore,verification and validation of the results have been accomplished from the standpoint of energy conservation law applied to scattering,and based on the reciprocity theorem.
文摘To evaluate the gastrocnemius/soleus and biceps brachii muscle stiffness by Acoustic Radiation Force Impulse (ARFI) elastography in the hemiplegia patients, sixty patients with hemiplegia after stroke were recruited. Baseline data were collected including age, gender, body mass index, education level, dominant side, affected side, time since stroke, stroke etiology. All patients were evaluated with before treatment and posttreatment with Broonstroom staging, Modified Ashworth spasticity scale, and Functional Independence Measures scale. The patient was divided into 3 groups: 1) Neuromuscular electrical stimulation group, 2) Rehabilitation group, 3) Neurumusculer electrical stimulation + Rehabilitation group. Affected and unaffected side biceps and gastrocnemius, ARFI elastography measurements were used to measure thickness and elastic values. In addition, before and after treatment, length and thickness were measured from all patients. Of the 60 subjects, 28 were female (46.7%) and 32 (53.3%) were males, with an average age of 58.42 ± 9.03 years. There was a significant difference between the upper and lower limbs after the treatment in terms of Brunstroom staging. In terms of Modified Ashworth scale, there was a significant difference in lower extremity only after treatment. When compared to the affected/unaffected side, before and after treatment, there was a significant difference in the measurements in both the medial gastrocnemius and the lateral gastrocnemius in all three groups. Further research with larger numbers of patients for longer periods is needed to clarify the relationship between the muscle hardness and degree of spasticity.
基金Training Program for Young Qhuang Scholars[Chinese Medicine Education Letter(2022)No.256]Key Research and Development Program of Anhui Province(No.202204295107020001)+1 种基金Anhui Young Leaders Reserve Talent Project[No.4,Middle Development(2022)]National Natural Science Foundation of China(No.81973825,82104783)。
文摘Objective:Acoustic radiation force impulse(ARFI)was applied to measure Shear wave velocity(SWV)of liver in patients with Wilson's disease(WD).To investigate the relationship between SWV and the serological indexes of liver fibrosis,such as type Ⅳ collagen(CⅣ),hyaluronic acid(HA),type Ⅲ procollagen peptide(PⅢNP),laminin(LN),APRI score(Asparate Aminotransfer to Platelet Ratio Index),and FIB-4 index(FIB-4 index).The clinical efficacy of GandouTang(GDT)in the treatment of liver fibrosis in WD with damp-heat internalization was also observed.Methods:80 cases of WD patients who met the inclusion criteria were randomly divided into the treatment group and the control group,with 40 cases in each group.The control group was treated with Sodium Dimercaptopropylsulfonate(DMPS)and the treatment group was additionally treated with the traditional Chinese medicine GDT.One course for 8 days,a total of 6 courses.The levels of SwV and four serological indicators of liver fibrosis(PⅢNP,HA,CⅣ,LN),APRI score and FIB-4 index were compared before and after treatment.Pearson correlation test was used to analyze the correlation between SWV and HA,CⅣ,LN,PⅢNP,APRI score and FIB-4 index.The effects of GDT on SWV,liver fiber,APRI and FIB-4 were evaluated according to the treatment plan.Results:①The SWV was positively correlated with FIB-4(r=0.83),APRI(r=0.82),HA(r=0.87),CⅣ(r=0.71),LN(r=0.85)and PINP(r=0.77).②Before treatment,there were no significant differences in SWV level,PⅢNP,HA,CⅣ,LN,APRI and FIB-4 levels between two groups(P>0.05).After treatment,the levels of PⅢNP,HA,LN,SWV,APRI and FIB-4 in both groups were significantly decreased(P<0.05,P<0.01),and the levels in the treatment group were lower than those in the control group.There were no significant specific changes in CⅣ level(P>0.05).Conclusion:SWV value can reflect the degree of WD liver fibrosis,and is positively correlated with HA,PⅢNP,CⅣ,LN,FIB-4 index and APRI score.On the basis of the treatment of protecting liver and expelling copper with western medicine,plus the treatment of traditional Chinese medicine GDT can effectively improve the degree of liver fibrosis in WD patients with damp-heat accumulation.
文摘AIM:To investigate whether a noninvasive measurement of tissue strain has a potential usefulness for management of nonalcoholic steatohepatitis(NASH).METHODS:In total 26 patients,23 NASHs and 3 normal controls were enrolled in this study.NASH was staged based on Brunt criterion.At a region of interest(ROI),a shear wave was evoked by implementing an acoustic radiation force impulse(ARFI),and the propagation velocity was quantif ied.RESULTS:Shear wave velocity(SWV) could be reproducibly quantified at all ROIs in all subjects except for 4 NASH cases,in which a reliable SWV value was not calculated at several ROIs.An average SWV of 1.34 ± 0.26 m/s in fibrous stage 0-1 was significantly slower than 2.20 ± 0.74 m/s and 2.90 ± 1.01 m/s in stages 3 and 4,respectively,but was not significantly different from 1.79 ± 0.78 m/s in stage 2.When a cutoff value was set at 1.47 m/s,receiver operating characteristic analysis showed significance to dissociate stages 3 and 4 from stage 0-1(P=0.0092) with sensitivity,specificity and area under curve of 100%,75% and 94.2%,respectively.In addition,the correlation between SWV and hyaluronic acid was significant(P<0.0001),while a tendency toward negative correlation was observed with serum albumin(P=0.053).CONCLUSION:The clinical implementation of ARFI provides noninvasive repeated evaluations of liver stiffness at an arbitrary position,which has the potential to shed new light on NASH management.
文摘Progressive fibrosis is encountered in almost all chronicliver diseases. Its clinical signs are diagnostic in advanced cirrhosis, but compensated liver cirrhosis is harder to diagnose. Liver biopsy is still considered the reference method for staging the severity of fibrosis, but due to its drawbacks(inter and intra-observer variability, sampling errors, unequal distribution of fibrosis in the liver, and risk of complications and even death), non-invasive methods were developed to assess fibrosis(serologic and elastographic). Elastographic methods can be ultrasound-based or magnetic resonance imaging-based. All ultrasoundbased elastographic methods are valuable for the early diagnosis of cirrhosis, especially transient elastography(TE) and acoustic radiation force impulse(ARFI) elastography, which have similar sensitivities and specificities, although ARFI has better feasibility. TE is a promising method for predicting portal hypertension in cirrhotic patients, but it cannot replace upper digestive endoscopy. The diagnostic accuracy of using ARFI in the liver to predict portal hypertension in cirrhotic patients is debatable, with controversial results in published studies. The accuracy of ARFI elastography may be significantly increased if spleen stiffness is assessed, either alone or in combination with liver stiffness and other parameters. Two-dimensional shearwave elastography, the Elast PQ technique and strain elastography all need to be evaluated as predictors of portal hypertension.