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Objective To study the application of laser speckle contrast algorithm in high-frequency ultrasound blood flow imaging. Methods The laser speckle contrast algorithm was extended to the field of high-frequency ultrasound blood flow imaging. The high-frequency ultrasound structure images were processed by using the classic laser speckle temporal contrast algorithm to suppress the static tissue signals, enhance the dynamic blood flow signals, and obtain the high-frequency ultrasound blood flow images. The simulation experiments on flow phantoms were conducted to verify the effectiveness of the algorithm, and then human skin tissue in vivo experiments were performed to verify the applicability of the algorithm. The performances of blood flow images which obtained from ultrasound structure images with different frames by laser speckle contrast algorithm were compared and analyzed. Results The blood flow information in a tube was clearly visible in the flow phantoms experiments. The static skin tissue signals were significantly suppressed, dynamic blood flow signals were strengthened in the human skin tissue in vivo experiments, and high-frequency ultrasound blood flow images were obtained. By comparing and analyzing the performances of blood flow images, the results showed that the best blood flow images could be obtained when the number of frame was set to 10 frames. Conclusions The speckle contrast algorithm is feasible and has good application prospects in high-frequency ultrasound blood flow imaging.
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Objective To explore the application of de-correlation algorithm to laser speckle blood flow imaging technique and study the blood flow velocity.Methods The principle and algorithm were analyzed for de-correlation laser speckle blood flow imaging.A laser speckle imaging platform was established,and de-correlation laser speckle blood flow imaging algorithm was used to execute microfluidic target experiment and animal experiment.De-correlation algorithm was applied to obtaining blood flow image and velocity curve of microfluidic target.Cross-correlation curve on the original speckle images were got with cross-correlation algorithm,and the original images corresponding to the peak points were selected to undergo computation with de-correlation algorithm,so that the minute information could be augmented on the blood vessel.Results The de-correlation laser speckle blood flow imaging algorithm could be used to obtain the blood flow information and velocity information during microfluidic target experiment and the animal experiment.Conclusion The de-correlation laser speckle blood flow imaging algorithm is feasible in laser speckle imaging,and has good application prospects.
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Objective To study the method of gray-scale blood flow imaging and image processing in condition of high frequency ultrasound,and the implementation of the system.Methods On the base of research of scattered signals of red blood cells in high frequency ultrasound,20 MHz ultrasound mechanical and linear scanning probe was used to transmit a number of pulses on a scan line.Pulse-echo subtraction method was used to obtain the blood flow information.At the end,simulated blood vascular was used to conduct flow imaging,and the obtained images were analyzed.Results Experiment results showed that clear blood flow images were obtained using this system.The noise from perivascular tissue could be filtered and the signals from blood flow could be enhanced after image processing.Conclusions In the detection of superficial blood vessel,blood flow signals can be obtained even using single pulse emitting via high frequency ultrasound.The blood flow imaging system can be implemented after image processing.
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Objective To non-invasive assess coronary blood flow velocity changes of patients with slow coronary flow phenomenon (SCFP) by coronary blood flow imaging (CFI).MethodsTwenty-one patients who had no significant coronary artery stenosis but had thrombolysis in myocardial infarction (TIMI) slow-flow phenomenon were the experimental group,nine patients who has no significant coronary stenosis and TIMI flow normal were the control group.Using corrected TIMI frame count(CTFC) assess velocity of coronary artery.The left ventricular end diastolic diameter,end systolic diameter,ejection fraction,E peak velocity,A peak velocity,E/A ratio were measured by conventional echocardiography.The distal anterior descending coronary artery diastolic peak flow velocity(Vmax),mean velocity(Vmean) and blood flow velocity time integral(VTI) were measured by CFI.Results The corrected TIMI frame count (CTFC) of left anterior descending artery blood flow in slow blood group was (45.37 ± 8.62)frame,that in control group was (15.94± 4.66)frame,the difference was statistically significant (t = -9.596,P =0.000).The conventional echocardiographic measurements of two groups were not significantly different.The left anterior descending artery Vmax was (22.86 ± 3.04)cm/s,Vmean was (17.62 ± 2.89)cm/s,VTIwas (8.49± 2.01)cm in the slow blood flow group,the left anterior descending artery Vmax was (31.78 ± 9.28) cm/s,Vmean was (23.67 ± 7.60) cm/s,VTI was (10.91 ± 4.47) cm in the control group.The difference was statistically significant.The left anterior descending artery CTFC with Vmax and Vmean was negative correlation in the control group and the slow blood flow group.The left anterior descending artery CTFC was negatively correlated with VTI in the control group,there was no correlation between left anterior descending artery CTFC and VTI in the slow blood flow group.Conclusions Coronary artery flow velocity in the left anterior descending artery was declined.CFI can reflect changes in coronary TIMI flow,but in the diagnosis of coronary slow flow phenomenon CFI has limitations.
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Objective To evaluate the diagnostic value of color Doppler blood flow imaging(CDFI) combined with two dimensional ultrasonography in the early breast cancer.Methods Forty five cases of breast mass(≤2 cm) were studied with CDFI and two dimensional ultrasonography.Results There were 21 cases with breast cancer and 24 cases with benign breast masses rich blood flow was demonstrated in 20 cases of breast cancer and in only seven cases of benign breast mass on CDFI.The Resistance index(RI)in the breast cancer group was higher(0.70?0.06)than that in benign breast mass group(0.60?0.06)(?