Objective To evaluate the applicability of Transcranial Doppler (TCD) monitoring in brain protection in the process of aortic dissection surgical procedure. Methods From Feburary 2007 to November 2007, six patients with type I aortic dissection underwent surgical procedure in Xuanwu Hospital of Capital Medical University. All patients are male with their age ranged from 48 to 60 years. During the operation, right subclavian arterial cannulation technique was used to protect the brain, and TCD monitoring was adopted to guide cerebral perfusion. The function of nervous system after operation was observed, and the minimental state examination (MMSE) was used to assess the cognitive function of the patients. A twoyear followup was done to monitor patients’ aorta condition. Results The time of cardiopulmonary bypass (CPB) was 136 to 350 minutes. The time of selected cerebral perfusion was 20 to 65 minutes. The lowest cerebral blood flow was 31% of basic level according to TCD monitoring. All patients were successfully treated without neurological complication and cognitive dysfunction when discharged from hospital. MMSE score was 28 to 30 points. During the twoyear followup after operation, all aortic false lumen were closed and there was no dissection recurrence. Conclusion Monitoring blood change with TCD monitoring technique is safe and effective in evaluating brain protection by selective cerebral perfusion in aortic dissection surgical procedure.
To evaluate the value of left ventricular diastolic function in type 2 diabetes mellitus (DM) using dual-gate Doppler and relative factors, we included 50 non-obesity and hypertension-free DM patients into the controlled group in the study along with 48 age-and-gender-matched healthy volunteer subjects. The peak early diastolic velocity (E), peak later diastolic velocity (A), deceleration time (DT), anterior mitral annulus diastolic peak velocity (e'), isovolumic relaxation time (IVRT), E/A, E/e', Tei index and TE-e' were measured with dual-gate Doppler. 20 subjects were randomly selected for repetitive analysis. Study showed statistical difference in E/A, DT, e', E/e', IVRT, Tei index and TE-e' between the two groups (P < 0.05). Linear regression analysis showed positive correlation between TE-e' and IVRT, course of DM patients and TE-e'(Beta=0.295, P=0.020), and HbA1C control level and TE-e'(Beta=0.399, P=0.010). Repeated analysis showed good reproducibility for both within and between groups. Dual-gate Doppler has clinical value in evaluating left ventricular diastolic function in type 2 diabetes mellitus patients. The course of type 2 diabetes mellitus patients and HbA1C control level were both closely related with left ventricular diastolic function.
In order to investigate the mechanism of blood supply to the delayed separated skin flap and the time and criteria for its transfer, 5 smallsized Banna pigs were selected to produce 14 skin flaps. In the experimental group the skin flap on one side was made from the middle of the back having an extrathin steel sheet intervened between the flap and the soft tissue of the back whereas the flap on the opposite side without a steel sheet intervened was served as the selfcontrol. The skin flaps were examined 3,7,10 and 20 days after the operation and 3,7 and 10 days after transfer, respectively, by (1) gross observation; (2) ultrasonic Doppler; (3) superficial skin temperature measurement and; (4) histomorphological examination. In the experimentalgroup the survival rate of the flap was 100 percent whereas in the control group all of the flaps had necrosis from 30 to 50 percent after the flap being transfered. In the experimental group, the echo sound from the arterial blood flow from ultrasonic Doppler was heard at the pedicle 7 days after the operation, and as time elapsed, the echo sound spread distally, whereas in the controls no echo sound could be heard over the skin flap. There was significant difference statistically between the experimental and control groups in the temperature of the flaps while the flaps were being transferred (P lt; 0.01). The external diameters of the blood vessels in the central area of the skin flap were larger in the experimental group, 0.8 to l.2mm in comparison to 0.4mm.
Objective To compare canine decel luarized venous valve stent combining endothel ial progenitor cells (EPC) with native venous valve in terms of venous valve closure mechanism in normal physiological conditions. Methods Thirty-six male hybrid dogs weighing 15-18 kg were used. The left femoral vein with valve from 12 dogs was harvested to prepare decelluarized valved venous stent combined with EPC. The rest 24 dogs were randomly divided into the experimental group and the control group (n=12 per group). In the experimental group, EPC obtained from the bone marrowthrough in vitro ampl ification were cultured, the cells at passage 3 (5 × 106 cells/mL) were seeded on the stent, and the general and HE staining observations were performed before and after the seeding of the cells. In the experimental group, allogenic decelluarized valved venous stent combined with EPC was transplanted to the left femoral vein region, while in the control group, the autogenous vein venous valve was implanted in situ. Color Doppler Ultrasound exam was performed 4 weeks after transplantation to compare the direction and velocity of blood flow in the distal and proximal end of the valve, and the changes of vein diameter in the valve sinus before and after the closure of venous valve when the dogs changed from supine position to reverse trendelenburg position. Results General and HE staining observations before and after cell seeding: the decelluarized valved venous stent maintained its fiber and collagen structure, and the EPC were planted on the decelluarized stent successfully through bioreactor. During the period from the reverse trendelenburg position to the starting point for the closure of the valve, the reverse flow of blood occurred in the experimental group with the velocity of (1.4 ± 0.3) cm/s; while in the control group, there was no reverse flow of blood, but the peak flow rate was decreased from (21.3 ± 2.1) cm/s to (18.2 ± 3.3) cm/s. In the control group, the active period of valve, the starting point for the closure of the valve, and the time between the beginning of closure and the complete closure was (918 ± 46), (712 ± 48), and (154 ± 29) ms, respectively; while in the experimental group, it was (989 ± 53), (785 ± 43), and (223 ± 29) ms, respectively. There was significant difference between two groups (P lt; 0.05).After the complete closure of valve, no reverse flow of blood occurred in two groups. The vein diameter in the valve sinus of the experimental and the control group after the valve closure was increased by 116.8% ± 2.0% and 118.5% ± 2.2%, respectively, when compared with the value before valve closure (P gt; 0.05). Conclusion Canine decelluarized venous valve stent combined with EPC is remarkably different from natural venous valve in terms of the valve closure mechanism in physiological condition. The former rel ies on the reverse flow of blood and the latter is related to the decreased velocity of blood flow and the increased pressure of vein in the venous sinus segment.
ObjectiveTo evaluate the dynamic changes of blood flow and blood pressure of acute hindlimb ischemia of rats by laser Doppler flowmetry (LDF) and laser Doppler perfusion imaging (LDPI). MethodsThe acute hindlimb ischemia model of rats was established by resection of rats femoral arteries of left hindlimb. The blood flow and blood pressure between operated and nonoperated hindlimbs were examined by LDF on 2, 7, 14, 28, and 49 d after operation. And the blood flow was evaluated by LDPI on 7 d after operation. ResultsAll rats survived after operation and no hindlimb necrosis occurred. The mean score was 2 on 14 d after operation and 1 on 49 d after operation. The ratio of blood flow between operated and nonoperated hindlimbs on 2 d after operation significantly increased from 1 to 1.31±0.439 (P=0.021). The ratio of blood flow on 7 d (0.82±0.538) and 14 d (0.93±0.294) after operation was significantly lower than that on 2 d after operation (P=0.032 and P=0.019), although the difference between the two former was not significant (P=0.502). Furthermore, the ratio of blood flow on 28 d after operation reached the bottom (0.41±1.970), which was obviously lower than that on 2, 7, and 14 d after operation (P=0.004, P=0.007, and P=0.006). The blood flow of operated hindlimbs recovered approximately the value before operation (0.98±0.093), which was significantly lower than that on 2 d (P=0.010), higher than that on 28 d (P=0.005), but not different from that on 7 d and 14 d after operation (P=0.126 and P=0.382). The ratio of blood pressure between operated and nonoperated hindlimbs on 2 d after operation significantly increased from 1 to 0.47±0.375 (P=0.031). The ratio of blood pressure decreased on 7 d after operation (0.44±0.118), which was not different from that on 2 d after operation (P=0.203). Furthermore, the ratio of blood pressure on 14 d after operation reached the bottom (0.35±0.115), which was obviously lower than that on 2 d and 7 d after operation (P=0.001 and P=0.036). On 28 d after operation, the ratio of blood pressure increased (0.54±0.146), which was significantly higher than that on 14 d after operation (P=0.008), while not different from that on 2 d (P=0.493) and 7 d after operation (P=0.551). The ratio of blood pressure recovered approximately the value before operation (0.97±0.094), which was significantly higher than that on 2, 7, 14, and 28 d (P=0.013, P=0.021, P=0.002, and P=0.031). ConclusionAcute hindlimb ischemia model of rats can be established by resection of rats femoral arteries of left hindlimb and the most serious stage of hindlimb ischemia is on 14-28 d after operation. LDF and LDPI are of importance for monitoring the dynamic changes of rats hindlimb ischemia after operation.
Objective To explore the value of color Doppler ultrasonography and plasma D-dimer in diagnosis of lower limb deep venous thrombosis (DVT).Methods The clinical data of 70 cases of patients with lower limb DVT diagnosed clinically were retrospectively studied. The lower limb venous of each patient was examined by color Doppler ultrasonography and the plasma level of D-dimer were measured, furthermore the plasma levels of D-dimer in different phase and different type of thrombosis were compared. Results The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of plasma D-dimer and ultrasonography examination in lower limb DVT were 100%, 66.7%, 97.0%, 100%, and 97.1%, and 98.4%, 83.3%, 98.4%, 83.3%, and 97.1%, respectively. The plasma D-dimer in acute phase 〔(6 451±4 012.22) μg/L〕 and subacute phase 〔(2 063±1831.35) μg/L〕 of lower limb venous thrombosis were significantly higher than that in normal control group 〔(310±66.70) μg/L〕, Plt;0.01 and Plt;0.05, which was not different from that in chronic phase 〔(466±350.52) μg/L〕. Meanwhile, the plasma D-dimer in mixed limb venous thrombosis group 〔(4 464±3 753.16) μg/L〕 and central limb venous thrombosis group 〔(2 149±1 911.53) μg/L〕 were significantly higher than that in control group (Plt;0.05 and Plt;0.01), which was not different from that in peripheral limb venous thrombosis group 〔(560±315.62) μg/L〕. Conclusion Color Doppler ultrasonography is an optimal method and the plasma D-dimer is a predictive index in diagnosis of lower limb DVT.
OBJECTIVE: To investigate the location of transverse rectus abdominis musculocutaneous (TRAM) flap perforators on abdomen skin and the peak systolic flow velocities of the perforators. METHODS: A series of 94 consecutive patient’s TRAM flap perforators were detected by color-flow duplex Doppler scanning peroperatively. Perforator locations were tabulated on the abdomen skin according to their vertical position relative to the umbilicus and their lateral location relative to the abdominal midline. RESULTS: The perforators on both left and right side of TRAM flap were quite not symmetry. The peri-umbilical region contained 81.1% of the perforators. All perforators were detected with peak systolic flow velocities ranging from 5 to 81 cm/s. CONCLUSION: The preoperative color-flow Doppler localization of TRAM flap perforators improves the surgeon’s ability to design the flap in order to capture the dominant vessels, and select single- or double-pedicle and free TRAM flaps based on each patient’s individual characteristics.
The ultrasound Doppler fetal heart rate measurement is the gold standard of fetal heart rate counting. However, the existing fetal heart rate extraction algorithms are not designed specifically to suppress the high maternal interference during the second stage of labor, and false detection occurrences are common during labor. With this background, a method combining time-frequency frame template library optimal selecting and non-linear template matching is proposed. The method contributes a template library, and the optimal template can be selected to match the signal frame. After the short-time Fourier transform of the signal, the difference between the signal and the template is optimized by leaky rectified linear unit (LReLU) function frame by frame. The heart rate was calculated from the peak of the matching curve and the heart rate was calculated. By comparing the proposed method with the autocorrelation method, the results show that the detection accuracy of the proposed method is improved by 20% on average, and the non-linear template matching of 23% samples is at least 50% higher than the autocorrelation method. This paper designs the algorithm by analyzing the characteristics of the interference and signal mixing. We hope that this paper will provide a new idea for fetal heart rate extraction which not only focuses on the original signal.
OBJECTIVE: To discuss clinical application of the color Doppler ultrasonography in diagnosis and treatment of cavernous hemangioma in deep subcutaneous tissue. METHODS: From 1996, 15 cases of cavernous hemangioma were diagnosed and located with color Doppler ultrasonography and were embolized under monitoring of the ultrasonography or resected by operation before re-examination of the hemangioma via the color Doppler ultrasonography after the intervention. RESULTS: Direct embolization was achieved in 10 cases after pinpoint location of the hemangioma by the ultrasonography, and guided embolization was performed successfully in 2 cases via the monitoring of ultrasonography, and operation had to be adopted to remove the focus. No reoccurrence of the hemangioma was observed in all the cases. CONCLUSION: Cavernous hemangioma in deep subcutaneous tissue could be easily diagnosed and located with color Doppler ultrasonography, and could be removed by embolization under monitoring of the ultrasonography successfully.
Objective To investigate the effectiveness of high frequency color Doppler ultrasound for detecting perforators in the anterolateral thigh (ALT) flap surgery. Methods Between February 2011 and July 2012, 8 patients underwent high frequency color Doppler ultrasound to detect the perforator anatomy before ALT flap surgery. There were 5 males and 3 females, aged 21-46 years (mean, 34 years). Defects were caused by excision of squamous cell carcinoma in 2 cases, by scalp avulsion in 2 cases, by soft tissue necrosis after neck trauma in 1 case, by excision of groin fibrosarcoma in 1 case, by excision of groin melanoma in 1 case, and by malformation of the face in 1 case. The defect size varied from 12 cm × 7 cm to 22 cm × 18 cm. The perforator with wider caliber, faster flow speed, and shorter intramuscular trajectory was selected, and the flap was designed according to the observed results, which size varied from 14 cm × 9 cm to 25 cm × 20 cm. The donnor sites were repaired by free skin graft. Results Totally, 19 perforators in the flap area were detected by high frequency color Doppler ultrasound, and 18 were identified during operation, with an accuracy rate of 94.7%. The point going out muscle, the travel and direction of perforators observed during operation were basically in accordance with those detected by high frequency color Doppler ultrasound. The other flaps survived, and obtained healing by first intention except 1 flap which had partial fat necrosis with healing by second intention. The skin graft at donor site survived. All patients followed up 4-16 months (mean, 8 months). The flaps had good color and texture. Conclusion High frequency color Doppler ultrasound is a valuable imaging modality for the preoperative assessment of the vascular supply for ALT flap.