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.
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.
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.
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.
ObjectiveTo investigate the application value of contrast-enhanced ultrasound (CEUS) technique to assist the repair of oral and maxillofacial defects by superficial inferior epigastric artery perforator flap.MethodsSixteen oral cancer patients, 10 males and 6 females, who were to undergo superficial inferior epigastric artery perforator flap repair between June 2018 and February 2020, were selected, with an average age of 55.8 years (range, 24-77 years). There were 13 cases of squamous cell carcinoma, 2 cases of adenoid cystic carcinoma, and 1 case of mucinous epidermis-like carcinoma. The color Doppler ultrasound (CDUS) and CEUS were used to screen the superficial inferior epigastric artery, assisted in the design of the flap, and compared it with the actual intraoperative exploration. The sensitivity, specificity, positive predictive value, and negative predictive value of CEUS and CDUS examinations were analyzed. Fourteen of 16 patients were repaired with superficial inferior epigastric artery perforator flap, and 2 patients were repaired with superficial iliac artery flap because the source artery was not found. After surgery, regular follow-up was performed to check for disease recurrence and metastasis and to evaluate the appearance of the patien’s donor area, the recovery of transoral feeding function, and the presence of complications.ResultsComparison of preoperative CDUS and CEUS findings and intraoperative exploration showed that CEUS had 100% sensitivity, specificity, positive predictive value, and negative predictive value for vascular exploration of the superficial inferior epigastric artery perforator flap, compared with 57%, 100%, 100%, and 25% for CDUS. The preoperative CDUS identified 25 penetrating vessels in 14 cases repaired with superficial inferior epigastric artery flaps. All vessel signals were enhanced by CEUS enhancement, and an additional 11 penetrating vessels were identified confirmed intraoperatively. The preoperative CEUS measurements of the initial diameter of superficial arteries in the abdominal wall were significantly higher than both CDUS and intraoperative measurements (P<0.05); the difference in peak systolic velocity between CEUS and CDUS measurements was significant (t=3.708, P=0.003). One case of superficial epigastric artery perforator flap developed venous embolism crisis at 48 hours after operation, the wound healing delayed. The other incisions in donor sites healed by first intention. All the patients were followed up 3-12 months, with an average of 8 months. No recurrence or metastasis appeared during the follow-up. There was no serious complications such as abdominal wall hernia, the location of abdominal scarring was hidden, and transoral feeding was resumed.ConclusionThe superficial inferior epigastric artery perforator flap with small injury in supply area and hidden scar location is a better choice for repairing oral and maxillofacial defects. The use of CEUS technique to assist the preoperative design of the superficial inferior epigastric artery perforator flap has good feasibility and high accuracy.
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 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.
ObjectiveTo observe the color Doppler flow imaging (CDFI) features of vitreoretinal lymphoma (VRL). MethodsRetrospective case series. From January 2022 to December 2024, 71 eyes of 42 patients diagnosed with VRL at the Eye Center of Beijing Tongren Hospital were enrolled. Among them, 17 were male and 25 female; 29 had bilateral and 13 unilateral involvement. Age ranged 17-78 years (median 59 years). Eleven cases had histopathologic confirmation and 31 were clinically diagnosed. All patients underwent CDFI and optical coherence tomography (OCT). CDFI findings were analyzed, noting the presence or absence of vitreous opacities (centrifugal distribution), posterior vitreous detachment (PVD), retinal detachment, and retinal elevated lesions. With Doppler overlay, blood flow within retinal lesions was assessed. The χ2 test was used to compare the detection rates of retinal lesions by CDFI and OCT, while Cohen’s Kappa assessed agreement in identifying the depth of lymphoma cell infiltration. ResultsAmong 71 eyes, vitreous opacity occurred in 66 eyes (93.0%, 66/71), of which 40 eyes (60.6%, 40/66) showed centrifugal opacity. 58 eyes (81.7%, 58/71) had posterior vitreous detachment. Retinal detachment occurred in 7 eyes (9.9%, 7/71). Retinal occupying lesions occurred in 23 eyes (32.4%, 23/61), of which 15 eyes (65.2%, 15/23) showed blood flow signals on the surface of the lesions but no blood flow signals inside the lesions by CDFI, and OCT showed that tumor cells gathered under the retinal pigment epithelium. CDFI showed blood flow signals inside the lesions in 8 eyes (34.8%, 8/23), and OCT showed that tumor cells gathered between retinal neuroepithelial layers. The lesion detection rate of OCT (69.6%, 16/23) was significantly lower than that of CDFI (100.0%, 23/23) (χ2= 6.066, P=0.014). OCT and CDFI showed perfect agreement in determining the depth of tumor cell infiltration (Kappa=1.0).ConclusionsThe ultrasonographic manifestations of VRL include vitreous opacity, PVD, and some retinal occupying lesions. Vitreous opacity often presents a characteristic centrifugal distribution. By observing whether there is blood flow signal in retinopathy using Doppler, the level of lymphoma cell infiltration can be suggested.
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.
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.