The value of color Doppler flow imaging （CDFI） and intravenous contrast-enhanced ultrasound （CEUS） for assessing the transplanted liver and early diagnosing complications by examining hemodynamic changes was discu...The value of color Doppler flow imaging （CDFI） and intravenous contrast-enhanced ultrasound （CEUS） for assessing the transplanted liver and early diagnosing complications by examining hemodynamic changes was discussed. Seventy-five patients with orthotopic liver transplantation （OLT） underwent CDFI. The following parameters were measured： peak systolic velocity （PS）, resistance index （RI） and Doppler perfusion index （DPI） of the hepatic artery （HA）, time average velocity （TAV） of portal vein （PV） and velocity of hepatic vein （HV） in different stages postoperation, And 11 patients of them received CEUS. Thirty healthy subjects were enrolled as controls, The results showed that： （1） In 23 patients without obvious complications, TAV of PV within 15 days post-operation was significantly higher than in controls （P〈0.05）, PS and DPI of HA within 7 days postoperation were lower, but RI was higher than in controls （P〈0.05）; （2） When the hepatic artery thrombosis （HAT） occurred, PS and DPI of HA were obviously decreased, but TAV of PV significantly increased like a high saw-tooth wave; （3） While rejection occurred, both TAV of PV and PS of HA were decreased with the increase in RI of HA, and the triphasic wave of HV disappeared and displayed as saw-tooth wave; （4） The incidence of biliary complications in liver transplantation was increased when DPI was reduced; （5） Seven cases of hepatic carcinoma relapse after OLT demonstrated hyperecho in the arterial phase and hypoecho in the portal and later phase on CEUS; （6） In 2 cases of HA thrombus, there was no visualized enhancement in arterial phase of CEUS, but enhancement during the portal vein and parenchymal phase. It was concluded that the hemodynamic changes of PV, HA and HV in the transplanted liver are valuable for assessing the transplanted liver and early diagnosing complications on CDFI and CEUS.展开更多
Cerebral blood flow of 10 asphyxiated term newborns was continuously measured during the first 7 days of life and compared with that of 10 normal term infants by CDI. Frequency spectrum and blood flow variables in the...Cerebral blood flow of 10 asphyxiated term newborns was continuously measured during the first 7 days of life and compared with that of 10 normal term infants by CDI. Frequency spectrum and blood flow variables in the anterior, middle and posterior cerebral arteries were studied. The results showed evidently lower systolic amplitude in patients than that in normal subjects. End diastolic amplitude was zero in part of vessels, and values of bloed flow variables were all lower in day 1 of the life as compared with the control groups. Frequency spectrum recovered to normal patterns in 9 survived infants in day 2. but blood flow variables recovered to normal by day 7. Values of resistance index (RI) rose to 1 in some vessels of moderate hypoxic ischemic encephalopathy (HIE) infants and stayed at 1 in the severe HIE infants. It is concluded that low CBF plays a key role in brain damage of post-asphyxiated newborns and RI may be an important parameter in the evaluation prognosis.展开更多
Color flow imaging(CFI)ultrasound technique can discover the tumor vascularity and superimposed it to convontional B-mode ultrasonogram in real-time. The flow velocity on spectral Doppler sonogram can be measured by s...Color flow imaging(CFI)ultrasound technique can discover the tumor vascularity and superimposed it to convontional B-mode ultrasonogram in real-time. The flow velocity on spectral Doppler sonogram can be measured by setting the sample volume to any selected site.One hundred and thirty-six patients with solid hepatic space-occupied lesions had been admitted and 113 cases were confirmed by operation and pathology,23 patients were strongly suspected by hepatic angiography (HAA).Ninety nine patients with 109 nodules were finally diagnosed as hepatic cellular carcinoma(HCC).According to color flow distribution pattern,3 kinds of color configuation had been nominated.Tumor vascularity discovered by CFI,especially the arterial blood flow was easy to be recognized,and its emerge rate was quite different between HCC group(94.5%)and hemangioma(HCH)group(17.07%)(P<0.01).Spectral Doppler studies were also carried out in these cases and the detectability of arterial flow in HCC group(95.41%)was much higher than that to HCH group (21. 95%) (P<0. 005).Resistant index(RI)and pulsatile index(PI)could be used to differentiate HCC (>0. 50 and >0.80 respectively)from HCH (P<0.001 and P<0.001 respectively).Arterial-portal(A-P) shunt could also be detected by CFI and spectral Doppler(mostly its Vmax>0.6m/s).The detection rate of A-P shunt was 64% in HCC group,but no case could be detected in HCH group.展开更多
目的探讨联合超微血流成像(superb microvascular imaging,SMI)和彩色多普勒血流显像(color Doppler flow imaging,CDFI)在乳腺影像学报告和数据系统(breast imaging reporting and data system,BI-RADS)分级为4类的微小结节诊断中的应...目的探讨联合超微血流成像(superb microvascular imaging,SMI)和彩色多普勒血流显像(color Doppler flow imaging,CDFI)在乳腺影像学报告和数据系统(breast imaging reporting and data system,BI-RADS)分级为4类的微小结节诊断中的应用,并与超声造影(contrast-enhanced ultrasound,CEUS)结果比较。方法前瞻性纳入乳腺BI-RADS分级4类、最大径≤1 cm,并经术后病理检查证实的165例乳腺微小结节患者共165例病灶,其中良性病灶125例、恶性病灶40例,每例病灶均进行CDFI、SMI及CEUS检查,分析其声像图资料。采用Adler半定量法进行血流分级评价,比较CDFI和SMI显示微小结节内血流情况的差异。制定了CDFI、CDFI+SMI联合两种方式预测结节性质的诊断标准,分析了CDFI、CDFI和SMI联合及CEUS三种血流显像方法对乳腺微小结节性质的诊断价值。结果恶性乳腺微小结节患者患病年龄大于良性患者,CDFI及SMI对乳腺微小结节血流检出能力不同,CDFI血流显示率为47.3%(78/165)、SMI为83.6%(138/165)。以病理结果为金标准,CDFI、联合CDFI和SMI、CEUS三种方法诊断乳腺微小结节的灵敏度分别为72.5%、87.5%、72.5%,特异度分别为60.8%、59.2%、82.4%,准确性分别为63.6%、66.1%、80.0%,曲线下面积(area under the curve,AUC)分别为0.665、0.771、0.772,且三种方式对微小结节诊断的差异有统计学意义,表明联合应用CDFI和SMI的方式优于单独使用CDFI。结论对于诊断为BI-RADS 4类的乳腺微小结节,联合应用CDFI和SMI,可有助于提高判断结节性质的灵敏度,并减少有创性检查超声造影的使用。展开更多
Quadrature demodulation is used in medical ultrasound imaging to derive the envelope and instantaneous phase of the received radio-frequency(RF) signal.In quadrature demodulation,RF signal is multiplied with the sine ...Quadrature demodulation is used in medical ultrasound imaging to derive the envelope and instantaneous phase of the received radio-frequency(RF) signal.In quadrature demodulation,RF signal is multiplied with the sine and cosine wave reference signal and then low-pass filtered to produce the base-band complex signal,which has high computational complexity.In this paper,we propose an efficient quadrature demodulation method for B-mode and color flow imaging,in which the RF signal is demodulated by a pair of finite impulse response filters without mixing with the reference signal,to reduce the computational complexity.The proposed method was evaluated with simulation and in vivo experiments.From the simulation results,the proposed quadrature demodulation method produced similar normalized residual sum of squares(NRSS) and velocity profile compared with the conventional quadrature demodulation method.In the in vivo color flow imaging experiments,the time of the demodulation process was 5.66 ms and 3.36 ms,for the conventional method and the proposed method,respectively.These results indicated that the proposed method can maintain the performance of quadrature demodulation while reducing computational complexity.展开更多
文摘The value of color Doppler flow imaging （CDFI） and intravenous contrast-enhanced ultrasound （CEUS） for assessing the transplanted liver and early diagnosing complications by examining hemodynamic changes was discussed. Seventy-five patients with orthotopic liver transplantation （OLT） underwent CDFI. The following parameters were measured： peak systolic velocity （PS）, resistance index （RI） and Doppler perfusion index （DPI） of the hepatic artery （HA）, time average velocity （TAV） of portal vein （PV） and velocity of hepatic vein （HV） in different stages postoperation, And 11 patients of them received CEUS. Thirty healthy subjects were enrolled as controls, The results showed that： （1） In 23 patients without obvious complications, TAV of PV within 15 days post-operation was significantly higher than in controls （P〈0.05）, PS and DPI of HA within 7 days postoperation were lower, but RI was higher than in controls （P〈0.05）; （2） When the hepatic artery thrombosis （HAT） occurred, PS and DPI of HA were obviously decreased, but TAV of PV significantly increased like a high saw-tooth wave; （3） While rejection occurred, both TAV of PV and PS of HA were decreased with the increase in RI of HA, and the triphasic wave of HV disappeared and displayed as saw-tooth wave; （4） The incidence of biliary complications in liver transplantation was increased when DPI was reduced; （5） Seven cases of hepatic carcinoma relapse after OLT demonstrated hyperecho in the arterial phase and hypoecho in the portal and later phase on CEUS; （6） In 2 cases of HA thrombus, there was no visualized enhancement in arterial phase of CEUS, but enhancement during the portal vein and parenchymal phase. It was concluded that the hemodynamic changes of PV, HA and HV in the transplanted liver are valuable for assessing the transplanted liver and early diagnosing complications on CDFI and CEUS.
文摘Cerebral blood flow of 10 asphyxiated term newborns was continuously measured during the first 7 days of life and compared with that of 10 normal term infants by CDI. Frequency spectrum and blood flow variables in the anterior, middle and posterior cerebral arteries were studied. The results showed evidently lower systolic amplitude in patients than that in normal subjects. End diastolic amplitude was zero in part of vessels, and values of bloed flow variables were all lower in day 1 of the life as compared with the control groups. Frequency spectrum recovered to normal patterns in 9 survived infants in day 2. but blood flow variables recovered to normal by day 7. Values of resistance index (RI) rose to 1 in some vessels of moderate hypoxic ischemic encephalopathy (HIE) infants and stayed at 1 in the severe HIE infants. It is concluded that low CBF plays a key role in brain damage of post-asphyxiated newborns and RI may be an important parameter in the evaluation prognosis.
文摘Color flow imaging(CFI)ultrasound technique can discover the tumor vascularity and superimposed it to convontional B-mode ultrasonogram in real-time. The flow velocity on spectral Doppler sonogram can be measured by setting the sample volume to any selected site.One hundred and thirty-six patients with solid hepatic space-occupied lesions had been admitted and 113 cases were confirmed by operation and pathology,23 patients were strongly suspected by hepatic angiography (HAA).Ninety nine patients with 109 nodules were finally diagnosed as hepatic cellular carcinoma(HCC).According to color flow distribution pattern,3 kinds of color configuation had been nominated.Tumor vascularity discovered by CFI,especially the arterial blood flow was easy to be recognized,and its emerge rate was quite different between HCC group(94.5%)and hemangioma(HCH)group(17.07%)(P<0.01).Spectral Doppler studies were also carried out in these cases and the detectability of arterial flow in HCC group(95.41%)was much higher than that to HCH group (21. 95%) (P<0. 005).Resistant index(RI)and pulsatile index(PI)could be used to differentiate HCC (>0. 50 and >0.80 respectively)from HCH (P<0.001 and P<0.001 respectively).Arterial-portal(A-P) shunt could also be detected by CFI and spectral Doppler(mostly its Vmax>0.6m/s).The detection rate of A-P shunt was 64% in HCC group,but no case could be detected in HCH group.
文摘目的探讨联合超微血流成像(superb microvascular imaging,SMI)和彩色多普勒血流显像(color Doppler flow imaging,CDFI)在乳腺影像学报告和数据系统(breast imaging reporting and data system,BI-RADS)分级为4类的微小结节诊断中的应用,并与超声造影(contrast-enhanced ultrasound,CEUS)结果比较。方法前瞻性纳入乳腺BI-RADS分级4类、最大径≤1 cm,并经术后病理检查证实的165例乳腺微小结节患者共165例病灶,其中良性病灶125例、恶性病灶40例,每例病灶均进行CDFI、SMI及CEUS检查,分析其声像图资料。采用Adler半定量法进行血流分级评价,比较CDFI和SMI显示微小结节内血流情况的差异。制定了CDFI、CDFI+SMI联合两种方式预测结节性质的诊断标准,分析了CDFI、CDFI和SMI联合及CEUS三种血流显像方法对乳腺微小结节性质的诊断价值。结果恶性乳腺微小结节患者患病年龄大于良性患者,CDFI及SMI对乳腺微小结节血流检出能力不同,CDFI血流显示率为47.3%(78/165)、SMI为83.6%(138/165)。以病理结果为金标准,CDFI、联合CDFI和SMI、CEUS三种方法诊断乳腺微小结节的灵敏度分别为72.5%、87.5%、72.5%,特异度分别为60.8%、59.2%、82.4%,准确性分别为63.6%、66.1%、80.0%,曲线下面积(area under the curve,AUC)分别为0.665、0.771、0.772,且三种方式对微小结节诊断的差异有统计学意义,表明联合应用CDFI和SMI的方式优于单独使用CDFI。结论对于诊断为BI-RADS 4类的乳腺微小结节,联合应用CDFI和SMI,可有助于提高判断结节性质的灵敏度,并减少有创性检查超声造影的使用。
基金Project supported by the National Key Technology R&D Program of China(No.2011BAI12B02)the Fundamental Research Funds for the Central Universities,China(Nos.2014FZA5019 and 2015FZA5019)
文摘Quadrature demodulation is used in medical ultrasound imaging to derive the envelope and instantaneous phase of the received radio-frequency(RF) signal.In quadrature demodulation,RF signal is multiplied with the sine and cosine wave reference signal and then low-pass filtered to produce the base-band complex signal,which has high computational complexity.In this paper,we propose an efficient quadrature demodulation method for B-mode and color flow imaging,in which the RF signal is demodulated by a pair of finite impulse response filters without mixing with the reference signal,to reduce the computational complexity.The proposed method was evaluated with simulation and in vivo experiments.From the simulation results,the proposed quadrature demodulation method produced similar normalized residual sum of squares(NRSS) and velocity profile compared with the conventional quadrature demodulation method.In the in vivo color flow imaging experiments,the time of the demodulation process was 5.66 ms and 3.36 ms,for the conventional method and the proposed method,respectively.These results indicated that the proposed method can maintain the performance of quadrature demodulation while reducing computational complexity.
