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.
Objective To discuss the relationship between the changes of hepatic blood flow detected by usingspectral Doppler ultrasound and serum TNF- α and IL-1 β levels after liver ischemia/reperfusion （I/R） of rat. Methods The hepatic ischemia 15 min and reperfusion models were established by using pringle method. The hepatic blood flow of hepatic artery and portal vein at 1， 6， and 24 hours after liver I/R were detected by using spectral Doppler ultrasound， the total blood flow volume （FV） was calculated， and the serum TNF- α and IL-1 β levels at each time point were detected. The correlation between the TNF-α， IL-1 β， and FV were analyzed. Results The FV at 1 hour and 6 hours after reperfusion in I/R group were less than those in sham operation （SO） group 〔（52.08±11.88） mL/min vs. （85.32±29.85） mL/min and （44.69±8.75）mL/min vs. （81.41±28.67） mL/min， P＜0.05〕. The FV at 24 hours after operation or reperfusion of 2 groups was no significant differences （P＞0.05）. The serum content of TNF-α at 1 hour after reperfusion in I/R group was higher than that in SO group 〔（310.52±39.83）pg/mL vs. （240.74±31.65）pg/mL， P＜0.05〕. The serum contents of TNF-α at 6 and 24 hours after operation or reperfusion of 2 groups were no significant differences （P＞0.05）. The serum contents of IL-1β at 1 hour and 6 hours in I/R group were higher than those in SO group 〔（38.08±3.73） pg/mLvs. （22.03±0.79） pg/mL and （27.44±6.11） pg/mL vs. （21.78±0.71） pg/mL， P＜0.05〕. The serum content of IL-1β at 24 hours after operation or reperfusion of 2 groups was no significant differences （P＞0.05）. There was a negative correlation between the FV and TNF-α or IL-1β （r=-0.43， P＜0.05；r=-0.46， P＜0.05）. Conclusions Spectral Doppler ultrasound can observe the changes of hepatic blood flow and evaluate the hepatic microcirculation indirectly. The hepatic blood flow after liver I/R decreases and it may be related to over expression of TNF-α and IL-1β.
Objective To investigate theory guidance for preoperative appraisal of advanced stage lower limb arteriosclerosis obliterans and clinical application of arteriae surales. Methods From September 2007 to June 2008, one hundred cases without obviously arteriosclerosis were collected to accepted color Doppler ultrasonography, and parameters of the arteriae surales were observed， such as location, macro-body morphous, caliber, and blood parameters value, meanwhile the caliber and blood parameters value of anterior tibial artery and posterior tibial artery were also measured. Results Detection rate of arteriae surales was 96% (96/100). Arteriae surales located midpiece sequentiae of popliteal fossa, and above flatfish tendinous arch, which in 89 cases were geminous branched from popliteal artery; in the remaining 7 cases, popliteal artery diverged a bole, walked 1-3 cm, then diverged two branches and ingressed gastrocnemius. Diameter and cross section area of arteriae surales were smaller than those of anterior tibial artery and posterior tibial artery (P＜0.05）, but peak flow rate of systolic phase, maximum positive direction flow rate of relaxing period and mean flow rate were not significantly differents between arteriae surales and anterior tibial artery or posterior tibial artery （P＞0.05）. The flow of geminous arteriae surales was 63.1% of anterior tibial artery, and 59.1% of posterior tibial artery. Conclusion Through the ultrasonic study, it is significant for clinical therapy to master the normal anatomy, blood parameters value and flow of arteriae surales.
ObjectiveTo explore the value of ultrasound evaluation and marking before arteriovenous internal fistula in end-stage renal disease hemodialysis patients. MethodsTwenty-five uremia end-stage patients were admitted into our nephrology department from January 2012 to July 2012. All of the patients had encountered several times of fistula failure or had difficulty in establishing the forearm arteriovenous fistula. We focused on observing the brachial artery, radial artery, cephalic vein, the basilica vein and great saphenous vein. We measured the diameter of the vessels and marked the trend of arteries and veins in the body surface under the ultrasonic navigation. Our goal was to look for appropriate bypass vessels in the elbow and the upper arm. ResultsFourteen patients had endured several times of fistula failure. Among the 14 patients, 9 patients completed the surgery of reengineering fistula and autogenous great saphenous vein transplantation, 2 accepted artificial vascular transplantation, 1 completed the removal of blood clots in the left upper limb artificial blood vessels and arteriovenous internal fistula molding, and 2 gave up surgery. Eleven patients could not complete the arteriovenous fistula operation for the fine forearm superficial vein. Of them, 2 patients accepted artificial vascular operation, 6 underwent autogenous great saphenous vein transplantation, 1 with slender radial artery in diameter completed higher position fistula between the brachial artery and median cubital vein, and 2 gave up surgery. ConclusionArteriovenous internal fistula preoperative ultrasound assessment and marking have very important value in improving the success rate of operation in end-stage uremia patients.
ObjectiveTo investigate the sonographic characteristics and diagnostic value of color Doppler sonography for patients with renal schwannoma. MethodsTen patients with pathologically confirmed renal schwannoma dimensional ultrasonography treated between January 2008 and May 2014 were included in this study. We analyzed and summarized their color flow distribution characteristics. ResultsThe ultrasound of the 10 patients showed substantial hypoechoic mass with clear boundary and complete capsule; color Doppler flow imaging displayed mass within the probe and a small amount of dotted blood flow information or no obvious blood flow information. Four patients were suspected to have schwannoma before surgery by ultrasound diagnosis, while the remaining 6 cases only showed benign lesions without clear diagnosis. All the patients underwent surgery subsequently under laparoscope, and resection of the tumor was performed with the integrity of normal kidney tissue retained. Postoperative recovery was good, and follow-up did not detect any recurrence. ConclusionColor Doppler ultrasound has a certain specificity on the diagnosis of renal schwannoma. Combined with other examination methods, it can not only give the clinicians a good suggestion, but avoid laparotomy.
ObjectiveTo evaluate the clinical value of color Doppler ultrasound in diagnosing prehepatic portal hypertension. MethodsA retrospective analysis was performed to analyze the results of color Doppler ultrasonography in 9 patients with prehepatic portal hypertension diagnosed between June 2012 and January 2015, including vessel diameter, shape, nature and direction of blood flow, and fistula blood flow spectrum. ResultsAmong the 9 patients, the color Doppler ultrasound found 3 patients with regional portal widened, increased and faster blood flow with the emergence of low-impedance spectrum artery, splenic vein widened with returning blocked and flocculent substance within the splenic vein lumen, irregular or streak-shaped low weak echo during splenic vein reduction, and unstable or weakened blood flow velocity. Two patients were confirmed with splenic vein thrombosis by ultrasound and other imaging methods with significantly reduced blood in splenic vein. For the other four patients with regional portal hypertension, obvious abnormalities in portal system were not detected by color Doppler ultrasound, but they were checked with other methods. The ultrasound positive diagnosis of the 9 patients was 5, with 4 missed. ConclusionThe color Doppler ultrasound has some values in screening, diagnosis and follow-up of prehepatic portal hypertension, but it can also be influenced by many factors with a high missed diagnosis rate. Carefully observing the portal system lumen structure, internal echo and blood flow combined with other imaging studies, and emphasizing clinical history of the patients can further improve diagnostic accuracy.
With introduction of current main methods for heart fluid mechanics researches, we studied the characteristics and weakness for three primary analysis methods based on magnetic resonance imaging, color Doppler ultrasound and grayscale ultrasound image, respectively. It is pointed out that particle image velocity (PIV),speckle tracking and block match have the same nature, and three algorithms all adopt block correlation. The further analysis shows that, with the development of information technology and sensor, the research for cardiac function and fluid mechanics will focus on energy transfer process of heart fluid, characteristics of Chamber wall related to blood fluid and Fluid-structure interaction in the future heart fluid mechanics fields.
This paper aims to analyze the impact of splenic vein thrombosis (SVT) on the hemodynamic parameters in hepatic portal vein system. Based on computed tomography (CT) images of a patient with portal hypertension and commercial software MIMICS, the patient's portal venous system model was reconstructed. Color Doppler ultrasound method was used to measure the blood flow velocity in portal vein system and then the blood flow velocities were used as the inlet boundary conditions of simulation. By using the computational fluid dynamics (CFD) method, we simulated the changes of hemodynamic parameters in portal venous system with and without splenic vein thrombosis and analyzed the influence of physiological processes. The simulation results reproduced the blood flow process in portal venous system and the results showed that the splenic vein thrombosis caused serious impacts on hemodynamics. When blood flowed through the thrombosis, blood pressure reduced, flow velocity and wall shear stress increased. Flow resistance increased, blood flow velocity slowed down, the pressure gradient and wall shear stress distribution were more uniform in portal vein. The blood supply to liver decreased. Splenic vein thrombosis led to the possibility of forming new thrombosis in portal vein and surroundings.
ObjectiveTo investigate the application of high frequency color Doppler ultrasound (HFCDU) combined with wide-field imaging in the preoperative navigation of anterolateral thigh perforator flap graft.MethodsBetween January 2017 and March 2018, 28 patients with skin and soft tissue defects were treated, including 22 males and 6 females, with an average age of 33.5 years (range, 17-66 years). The causes of injury included 2 cases of scald scar, 7 cases of heavy object crushing injury, 12 cases of traffic accident injury, 4 cases of fall injury, 2 cases of machine injury, and 1 case of infection ulcer. Injury sites included 6 cases of hand and wrist, 12 cases of lower leg, 10 cases of foot. After debridement, the wound area ranged from 6.0 cm×3.5 cm to 24.0 cm×9.0 cm, and all patients were treated with free circumflex femoral artery perforator flap graft. Combo of HFCDU and wide-field imaging navigation were done preoperatively to detect the origin, quantity, course, surface location, hemodynamic characteristics, and the relationship with body area of perforator branch of lateral circumflex femoral artery. According to the perforator information displayed by wide-field imaging of source artery, the dominant perforator was determined to be a pedicle for designed flap. The flap size ranged from 7.0 cm×4.5 cm to 26.0 cm×7.0 cm. The flap donor area was sutured directly.ResultsThe dominant perforator was successfully detected by HFCDU combined with wide-field imaging in 28 patients before operation. The existence of the perforator was confirmed during operation, and the location was accurate. The course characteristics of the perforate were consistent with the results of wide-field imaging. The grafted flaps survived completely among 27 patients after operation. Necrosis at the edge of the flap was observed in 1 patient, which healed after dressing change. All patients were followed up 3-12 months, with an average of 9 months. All the flaps have good blood supply, good elasticity and shape. The donor areas healed perfectly.ConclusionUsing HFCDU and wide-field imaging navigation for designing of anterolateral thigh perforator flaps can clearly show the characteristics of perforators, hemodynamic information, and the relationship with body area, so that the surgeons can understand the perforators more accurately and intuitively, and improve the success and efficiency of flap graft surgery.
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.