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Objective To study the difference of the values of Young's modulus between the middle part and the inferior extremity of rabbit renal cortex.Methods Ten Japanese white rabbits were used for this study.The right renal vein was ligated.At time intervals of 15,30,60 and 90 minutes after ligation,the values of Young's modulus from different parts of the right renal cortex were recorded.Independent sample t test was used to compare the difference of the values of Young's modulus from the middle part and the inferior extremity of renal cortex at the same time point.Single factor variance analysis was used to compare the values of Young's modulus at the same point at difference time.Results Before renal vein ligation,the values of Young's modulus from the middle part and the inferior extremity of renal cortex were(15.93±1.70)kPa and(4.66±1.4)kPa.After the ligation,the values from those two parts of the kidney were as follows: 15 min after ligation,(34.84±4.91)kPa and(10.95±3.09)kPa; 30 min after ligation,(41.55±3.19)kPa and(20.39±4.06)kPa; 60 min after ligation,(50.63±2.73)kPa and(30.96±4.98)kPa; 90 min after ligation,(56.61±2.96)kPa and(42.40±5.79)kPa.The value of Young's modulus from the middle part of renal cortex was significantly higher than the inferior extremity of renal cortex,and the difference was statistically significant(t=21.63,7.44,7.19,5.26 and 2.41,all P＜0.05).The values of Young's modulus from different parts of the renal cortex after renal vein ligation were significantly higher than those before the ligation(t=-3.30,3.38,-2.47,1.83,all P ＜ 0.05),and the values increased gradually with time increased after ligation(t=-5.31,8.26,-7.81,3.65,all P ＜ 0.05).Conclusions The values of Young's modulus from the middle part of renal cortex were higher than those of the inferior extremity of renal cortex determined by shear wave ultrasound elastic imaging technique.It is suggested that there is anisotropy in the renal cortex of rabbit.Prior to and within 90 min following renal vein ligation,the values of Young's modulus from the middle part of renal cortex were higher than those of the inferior extremity of renal cortex determined by shear wave ultrasound elastic imaging technique.
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Objective To find a new method for evaluating the left ventricular relaxation time constant Tau with aortic regurgitation by continuous wave Doppler.Methods Twelve Beagle dogs were included in the study.The dog aortic regurgitation model was produced under ultrasound guiding by carotid artery puncture.Aortic pressure was measured by pressure catheter and left ventricular pressure was measured by Millar catheter which was introduced into the left ventricular through cardiac apex.Then microspheres were injected into the left coronary artery under the guidance of ultrasound to induce acute ischemic left ventricular dysfunction,when left ventricular end-diastolic pressure increased more than 5 mmHg (1 mmHg=0.133 kPa).Dobutamine or esmolol was infused to alter left ventricular function.Aortic regurgitation velocity spectrum was recorded by the continuous-wave Doppler echocardiography in different hemodynamic status.At the same time,left ventricular pressure,dp/dt,aortic pressure and continuous ECG tracing were displayed on the multi-channel physiological recorder.Measurement was recorded of-dp/dtmax in the dp/dt tracings and the pressure at the time of-dp/dtmax in the left ventricular pressure tracings.Tau =-P/(dp/dtmax),Tau was the catheter-derived time constant (Taucatheter).Aortic regurgitation spectrum of original audio data was post-processed with MATLAB mathematical software.The spectral lines refresh time of about 300 μs was chosen to form a new Doppler spectrum.Three points:(t1,1 m/s),(t2,2 m/s) and (t3,3 m/s) were selected in aortic regurgitation velocity spectrum and tl,t2 and t3 was put into the corresponding Tau formula:Tau=(t2-t1)/ln[(ADP-C-4)/(ADP-C-16)],Tau=(t3-t1)/ln[(ADP-C-4)/(ADP-C-36)].Tau was the aortic regurgitant time constant (Tauultrasound).The difference between Taucatheter and Tauultrasound was compared by paired t test.The correlation between Taucatheter and Tauultrasound was analyzed by Pearson correlation analysis.Results Twelve dogs were successfully produced aortic regurgitation model.Two dogs died of ventricular fibrillation during the procedure of acute ischemic left ventricular diastolic dysfunction.The range of the Taucatheter was between 27.12 ms and 86.88 ms with an average of (48.973± 14.667) ms;the range of the Tauultrasound was between 28.13 ms and 90.18 ms with an average of (51.236± 15.146) ms.The difference was not statistically significant (t=1.841,P ＞ 0.05).Pearson correlation analysis showed that Taucatheter was positively correlated with Tatultrasound (r=0.89,P=0.000).Conclusion Choosing three points:(t1,1 m/s),(t2,2 m/s) and (t3,3 m/s) in aortic regurgitant velocity spectrum and putting into the corresponding formula,we can calculate Tau,which had a good correlation with the catheter-derived Tau.
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Objective To explore the new method for noninvasively measuring the time constant of left ventricular relaxation (Tau) in animals with mitral regurgitation by continuous-wave Doppler.Methods The acute ischaemic left diastolic heart failure with mitral regurgitation was produced in 9 dogs.Dobutamine hydrochloride or esmolol hydrochloride had been applied to change the hemodynamic states.In different hemodynamic states,left ventricular pressures,left atrial pressures,curves of dP/dt and continuous-wave mitral regurgitant spectra were synchronously recorded.Doppler spectra were laterly processed through Matlab workstation.Paired t-test was used to compare the difference between Tau-catheter (Tau-c) and Tau-doppler ultrasound (Tau-d),and the correlation between Tau-c and Tau-d was analyzed by Pearson correlation analysis.Results Thirty-nine hemodynamic status had been obtained in 9 dogs.Tau-c was 21.03-78.45 ms and the average was (48.76± 17.60) ms.Tau-d was 21.24-94.60 ms and the average was (49.33 ± 18.79) ms.There was no significant difference (t=0.353,P=0.726) between Tau-d and Tau-c.The correlation analysis between Tau-d and Tau-c suggested a strong positive relationship with the correlation coefficient (r=0.85,P ＜ 0.001).Conclusions The dog aortic regurgitation model under ultrasound guidance is less traumatic.The method of inducing left ventricular diastolic dysfunction by repeatedly injecting microspheres into the left coronary sinus is safe and reliable.Choosing three points (t1,1 m/s;t2,2 m/s;t3,3 m/s) in aortic regurgitant velocity spectrum and putting them into the corresponding formula,we can obtain Tau,which had a good correlation with the catheter-derived Tau.
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Objective To study the effect of heterogeneity in different parts of acute and chronic deep venous thrombus on the ultrasound shear wave elasticity value.Methods Fifteen Japanese rabbits were used to create an inferior vena cava (IVC) thrombus model via IVC ligation.Young's modulus of the thrombus head,body and tail were measured using ultrasonic shear wave elasticity technique on the fifth day (acute phase) and 14th day (chronic phase) of thrombus formation.Pathological sections were obtained from the IVC thrombus in five rabbits at the two points of time mentioned above.Pair t-test and one-way analysis of variance (ANOVA) were used to compare the data between groups.Results On the fifth day,Young's modulus values of the thrombus head,body and tail were (5.73 ±0.47)kPa,(7.82±0.63)kPa and (4.76±0.45)kPa respectively.ANOVA showed significant difference among three parts (F=134.468,P ＜ 0.01).The value of the thrombus body was significantly higher than that of the head and tail (both P ＜ 0.01),and the value of the head was significantly higher than that of the tail (P ＜ 0.01).On the 14th day,Young's modulus values of the thrombus head,body and tail were (12.46 ± 2.59)kPa,(15.08 ±2.71)kPa and (10.03 ± 2.02)kPa,respectively.ANOVA analysis also showed significant difference among three parts (F=10.539,P ＜ 0.01).The value of the thrombus body was significantly higher than that of the tail (P ＜ 0.01),and also higher than that of the head,although the difference was not significant (P ＞ 0.05).There was no significant difference between the head and tail (P ＞ 0.05).Young's modulus values of the thrombus head,body and tail in the chronic phase were significantly higher than those in the acute phase (t=-7.456,-7.989 and-8.159,respectively,all P ＜ 0.01).Pathological results showed that there was significant difference in thrombus structure and composition among different parts of the thrombus and among the thrombi in different individuals at corresponding points of time following thrombus formation.Conclusion There is significant heterogeneity among different parts of the same thrombus and among different thrombi at corresponding points of time after thrombus formation.Continual monitoring of the thrombus with ultrasound elasticity imaging may help to improve the accuracy of thrombosis staging.
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Objective To study the changes of Young's modulus value of the renal cortex,vertebral body and sinus when there was a different degree of acute renal artery stenosis.Methods 10 Japanese white rabbits were used for this study.The left renal artery was dissected.An ultrasound probe was placed on the left kidney,Young's modulus of the renal cortex,vertebral body and sinus were recorded using shear wave ultrasound elastic imaging technique during three stages:when the renal artery was intact (0％ stenosis),tied with a suture (＞ 50％ stenosis),and ligated (100％ stenosis).Renal tissue elasticity with different degrees of renal artery stenosis were compared.Pathological study was carried out in the kidneys,each with either 0％,＞ 50％ or 100％ renal artery stenosis.Results The mean values of Young's modulus from the renal cortex,vertebral body and sinus with different degrees of renal artery stenosis were as follows:0％ stenosis,(16.31 ±1.70) kPa,(13.38± 1.63) kPa,and (12.75±2.26) kPa;＞ 50％ stenosis,(14.16±2.34) kPa,(11.49±2.70) kPa,and (10.72±2.56) kPa;100％ stenosis,(11.35 ± 1.48) kPa,(8.39± 1.29) kPa,and (7.08 ± 1.52) kPa.The mean value of Young's modulus from the renal cortex was significantly higher than those from the renal vertebral body and sinus (P ＜ 0.05).The mean values of Young's modulus from different parts of the kidney decreased progressively with an increase in renal artery stenosis (P ＜ 0.05).The pathological study demonstrated that with the increase in the severity of renal artery stenosis,glomerular volume,renal interstitial capillary diameter and red blood cells decreased.When renal artery stenosis reached 100％,there was patch degeneration and inflammatory cell infiltration within the renal interstitium,and mild degeneration of tubular epithelial cells with obscure cell borders.Conclusions The value of Young's modulus from the renal cortex was higher than those from the renal pyramid and sinus in rabbits.The values of Young's modulus from the renal cortex,pyramid and sinus decreased with an increase in the severity of renal artery stenosis,which suggest that,in the study of the elasticity of the kidney,the renal artery blood flow dynamic state can obviously affect the value of the elasticity of the kidney.
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Objective To investigate the effect of patient positioning on the Duplex ultrasound evaluation of great saphenous vein reflux elicited by the pneumatic cuff method. Methods FFifty great saphenous veins (GSV) with relfux (relfux group) and iffteen with no prior history of venous disease (healthy group) were examined by duplex scanning in the supine, 20 degrees reverse-trendelenburg (RT-20), 40 degrees reverse-trendelenburg (RT-40) and standing position. Each GSV was assessed for relfux at three venous sites:two centimeter below the sapheno-femoral junction (SFJ), the greater saphenous vein in the mid thigh (MGV) and the greater saphenous vein in the upper calf (CGV). Pneumatic cuff compression pressure of conifned 100 mmHg (1 mmHg=0.133 kPa) was used onto the calf to elicit relfux. The incidence of positive venous relfux was calculated. The statistical differences of the peak relfux velocity and duration of relfux in four positions were analyzed. Results TThe relfux elicited in the standing position was set as the gold standard. In healthy group, there was no false positive results of relfux in supine, RT-20 and RT-40 positions. In relfux group, false negative results were found at all venous sites when limbs were examined in supine position [false negative rate:59%(19/32), 22%(11/50), 24%(12/50)]. At RT-20 and RT-40 positions, the incidence of venous relfux reached 100% at MGV and CGV, and false negative cases were only detected at SFJ [false negative rate:12%(4/32), 12%(4/32)]. The relfux time in standing, supine, RT-20 and RT-40 positions were (7.75±3.23) s, (5.27±3.66) s, (8.67±3.72) s, (8.55±3.93) s respectively. There were signiifcant differences among different positions in reflux time (F=56.9, P 0.05), except for supine position (q=4.11, P<0.01). Peak relfux velocity in standing, supine, RT-20 and RT-40 positions were (55.26±22.24) cm/s, (22.87±12.03) cm/s, (38.46±16.30) cm/s, (45.13±19.21) cm/s respectively. There were also signiifcant differences among different positions in peak relfux velocity (F=13.7, P<0.01). Comparing the supine, RT-20 and RT-40 positions with standing position, differences of the peak relfux velocity between them were all statistically signiifcant (q=12.71, 6.59, 3.98 respectively, all P<0.01). Conclusions When GSV reflux was examined by pneumatic cuff compression, false negative rate was higher in the supine position. RT-20 and RT-40 position were effective to detect GSV relfux, espically for GSV at mid-thigh and upper calf.
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Objective To evaluate the diagnostic value of ultrasound-guided pleural biopsy combined with thoracic biochemical detections in malignant and tuberculous pleural effusions. Methods Sixty-four patients with moderate or large pleural effusions and pleural thickening received the ultrasound-guided diagnostic pleural biopsy. All patients had chest CT enhancement scans to find out the suspicious pleural thickening preoperatively, facilitating the selection of puncture sites by ultrasound. Pleural tissue samples were sent for pathological examinations immediately. After successful achievements of pleural biopsy, ultrasound-guided aspiration or drainage was performed to alleviate symptoms, more importantly, to get pleural effusions for biochemical analysis. Biological results including carcinoembryonic antigen(CEA), CA125, CYFRA21 and lactate dehydrogenase(LDH) in malignant and tuberculous effusions were analyzed by group design t tests. The positive rates of CEA, CA125, CYFRA21, LDH in malignant and tuberculous effusions were compared by chi square tests. Results Pleural tissues in all cases were got by one pleural biopsy procedure. The strategy of pleural biopsy we used in this study had a successful rate reaching 100%(64/64), and 73% (46/64) patients had a definitive diagnosis as malignant or tuberculous effusion. Twenty-seven cases were diagnosed as malignant effusions and thirty-seven cases as tuberculous effusions based on the deifnitive clinical diagnosis. The positive rates of CEA, CA125, CYFRA21, LDH in malignant effusions were 100%(27/27), 100%(27/27), 100%(27/27), 89%(24/27) respectively, and 0%(0/37), 84%(31/37), 78%(29/37), 76%(28/37) respectively in tuberculous effusions. The positive rate of CEA between malignant and tuberculous effusions differed signiifcantly (χ2=64.0, P < 0.01), so did CA125 (χ2=3.1, P < 0.01) and CYFRA21(χ2=4.8, P<0.01). The average levels of CEA, CA125, CYFRA21, LDH in pleural effusion were (727.1±658.8)μg/L, (795.2±1249.6)×103 U/L, (296.2±320.7)μg/L, (1077.9±1058.5) U/L respectively, and (1.7±1.1)μg/L, (336.3±208.6)×103 U/L, (20.7±14.9)μg/L, (309.2±182.7) U/L in tuberculous effusions.There were signiifcant differences in CEA, CYFRA21 and LDH concentrations among malignant and tuberculous effusions (t=45.1, 27.4, 18.8 respectively, all P<0.01). Conclusion Ultrasound-guided pleural biopsy combined with CEA, CYFRA21 and LDH in pleural effusions had an important value in the etiological diagnosis of pleural effusions, while CA125 showed little value in the differential diagnosis.
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Objective To assess the clinical outcome of varicose veins with incompetent great saphenous vein(GSV) treated with ultrasound guided foam sclerotherapy. Methods Forty limbs with moderate to severe symptomatic varicose veins with incompetent GSV in 38 patients were injected with foam sclerosing agent (Fibro-Vein) under ultrasound guidance. There were 36 patients with unilateral varicose veins and 2 with bilateral varicose veins. No of them suffered from deep vein incompetence or perforating vein incompetence. Second injection was performed one month after the initial injection in 7 limbs. Thirty-eight of 40 limbs were followed up with clinical examination and duplex ultrasound scan 30-47 months (mean 40 months) after the treatment. Results Among 38 limbs with follow-up mild debilitation was found in two limbs(5. 3%). There were no other symptoms or complications. Duplex ultrasound demonstrated four type of results: type I, sclerosed GSV trunk with no detectable venous flow in 32 of 38 limbs (84. 2%) ;type II,patent GSV trunk in 3 limbs (7. 9%) ,two of them had mild reflux in the GSV trunk;type III,sclerosed GSV trunk and mild reflux in the GSV tributaries, 1/38(2. 6%) ; type IV,sclerosed proximal GSV trunk,patent distal GSV communicated with a superficial vein and mild reflux in the veins, 2/38 (5. 3% ). Conclusions Clinical examination and duplex ultrasound scan demonstrated excellent results of varicose veins with incompetent GSV treated with ultrasound guided foam sclerotherapy 40 months after the treatment. Sclerotherapy is less invasive treatment option for varicose veins with incompetent GSV with satisfactory clinical and cosmetic outcome.
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Objective To explore the usage of anatomic al M-mode echocardiography in observing pulmonary artery motion curve of pulmonary hypertension patients.Methods The subjects included 21 pulmonary hypertension patients complicated with tricuspid valve insufficiency, and 21 controls whose age and gender matched with the patient group. The inner diameter of main pulmonary artery and right atrium, acceleration time of pulmonary valve Doppler signal and maximum velocity of tricuspid insufficiency (ACTpv) were measured during routine echo examination. From the maximum velocity of tricuspid insufficiency the pulmonary artery systolic pressure (PASP) was calculated. The pulmonary artery motion curve and pulsating amplitude of pulmonary artery wall (PAWPA) was observed and measured with a home-made anatomical M-mode echocardiography with instrument. Results PAWPA in the patient group was lower, and simultaneously complicated with broader pulmonary artery, larger right atrium and shorter ACTpv in comparison with normal group (all P
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<p><b>OBJECTIVE</b>To evaluate the long-term results of percutaneous microwave coagulation therapy (PMCT) for primary hepatocellular carcinoma.</p><p><b>METHODS</b>From May 1994 to May 2000, 177 hepatocellular carcinoma patients with 265 nodules underwent PMCT with ultrasound (US) guidance. The tumor size varied from 1.5 to 8.7 cm (median 4.12 + 1.9 cm). Follow-up examination was carried out with colour US, CT, MRI and AFP. 184 nodules were re-biopsied during the follow up of 5 - 74 months (median 29 months).</p><p><b>RESULTS</b>After PMCT, colour Doppler flow signals disappeared in 92.0% (207/225) of patients. No enhancement was observed in 88.5% (138/156) by CT and 88.9% (32/36) by MRI. Re-biopsy of 184 nodules showed complete necrosis in 92.4% (170/184). Six resected lesions showed complete tumor necrosis in 5 and subtotal necrosis in 1. The 1- to 5-year survival rates were 90.1%, 76.9%, 68.3%, 64.2% and 57.8%, respectively. The survival rates of the well differentiated lesions were better than those of the poorly ones (P < 0.05). But there was not statistical significance between the moderately and the well differentiated ones. The new lesions development rates in 1 to 5 years were 26.1%, 37.8%, 43.5%, 48.6% and 58.9%, respectively. However, there was no severe complication.</p><p><b>CONCLUSION</b>Ultrasound-guided microwave coagulation is safe and effective for primary hepatocellular carcinoma. It can eliminate tumors less than 5 cm in diameter.</p>
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Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Carcinoma, Hepatocellular , Mortality , Therapeutics , Liver Neoplasms , Mortality , Therapeutics , Microwaves , Therapeutic Uses , Treatment OutcomeABSTRACT
Objective To study the worth of echo-tracking and M-echo in evaluating artery stiffness comparatively.Methods Fifty two rabbits were divided into 4 groups randomly:control group 1,hypercholesterinemia group,control group 2,and artherosclerosis group,there were 13 rabbits in each group.The rabbits were bred with normal or 2% cholesterol animal feeds according to their groups.The femoral artery blood pressure were measured with catheter.Artery stiffness of abdomen aorta of every rabbit was evaluated by echo-tracking and M-echo at the baseline and the end of the study by 2 doctors,and each doctor did twice.Results All the rabbits of artherosclerosis group had lipid plaques in the thorax and abdomen aortas,and the interior elastic fibers board under the plagues were disrupted.Echo-tracking was more stable and sensitive than M-echo in evaluating artery stiffness.pressure-strain elastic modulus(E?) and stiffness index(?) were sensitive stiffness indexes,but arterial compliance(AC) was not.The indexes of artery stiffness evaluated by echo-tracking with short view of the artery were stable too,but not sensitive compared with long view.E? was relative to diastolic diameter of artery and HDL-C positively(P0.05).Conclusions Echo-tracking is more stable and sensitive than Mecho in evaluation of artery stiffness,long view of the artery should be applied in the evaluation of artery stiffness with the technique of echo-tracking.E? and ? were sensitive artery stiffness indexes,but AC was not.
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0.05 ) when two doctors measured the same group patients with the same method. The coefficient of variation of IVRTd was bigger than that of IVRTm when two doctors measured the same group patients with two different methods. In four sets of data, three ones showed significant difference(P
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To study the diagnosis of pulmonary stenosis (PS) in patients with the secundum atrial septal defects(ASD) by the measurement of maximal velocity through pulmonary valve (Vpv max ). There were 98 cases with secundum ASD, and 27 cases with secundum ASD and PS diagnosed by echocardiography(TTE). All the cases with secundum ASD were confirmed by surgery. The diagnosis of 19 cases out of 27 cases as diagnosed by TTE were confirmed by surgery, and the other 8 cases were simple secundum ASD. These results suggested that the two dimensional echocardiography and Vpv max should be utilized in order to achieve a better diagnostic accuracy in the diagnosis of PS in the patients with ASD, and PS should be considered if the Vpv max increased to 2 65 to 3 25m/s.