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 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 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 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.
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 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.
Objective To investigate the accuracy of color Doppler ultrasound (CDU) and CT angiography (CTA) in the preoperative evaluation of perforator vessels in free posterior interosseous artery perforator (PIAP) flaps. Methods Between January 2020 and December 2023, 19 patients with hand skin and soft tissue defects caused by trauma were admitted. There were 11 males and 8 females, with a median age of 45 years (range, 26-54 years). The interval between injury and admission was 5-11 days (mean, 7.2 days). The skin and soft tissue defects were located on the dorsum of the hand in 8 cases and on the fingers in 11 cases. The size of defect ranged from 4.0 cm×2.5 cm to 7.5 cm×3.5 cm. After locating the perforator vessels through CDU and CTA before operation, the free PIAP flaps were designed to repair hand defects, with the size of 4.5 cm×3.0 cm-7.5 cm×4.0 cm. The defects of donor sites were directly sutured. The number and diameter of perforator vessels in the posterior interosseous artery detected by CDU and CTA were compared. The differences in localization of perforator vessels using CDU and CTA and their clinical effects were also compared to calculate the accuracy and recognition rate. During follow-up, the survival of the skin flap was observed, and the Vancouver scar scale (VSS) score was used to evaluate the healing of the donor site, while the visual analogue scale (VAS) score was used to evaluate the patient’s satisfaction with the appearance of the skin flap. Results The number and the diameter of PIAP vessels was 5.8±1.2 and (0.62±0.08) mm assessed by CDU and 5.2±1.0 and (0.60±0.07) mm by CTA, showing no significant difference between the two methods (P>0.05). The number, course, and distribution of perforator vessels of the PIAP vessels observed during operation were basically consistent with those detected by preoperative CDU and CTA. Compared with intraoperative observation results, the recognition rates of dominant perforating vessels by CDU and CTA were 95.0% (18/19) and 89.5% (17/19), respectively, and the accuracy rates were 100% (19/19) and 84.2% (16/19), with no significant difference between the two methods (P>0.05). All flaps survived after operation, and all wounds and incisions at donor sites healed by first intention. All patients were followed up 6-13 months (mean, 8.2 months). At last follow-up, the skin flaps had elasticity and soft texture, with the patient satisfaction VAS score of 9.2±0.8. The donor sites had no obvious scar hyperplasia with the VSS score of 11.7±0.9. Conclusion CDU and CTA accurately identify the dominant perforator vessels and provide reliable information for vessel localization, facilitating precise flap harvesting and minimizing donor site injury. However, CDU offers superior visualization of distal end of perforator vessels in the forearm compared to CTA.
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.
Objective To observe the ultrasonographic features of idiopathic uveal effusion syndrome (IUES). MethodsA retrospective controlled study. From January 2012 to December 2023, 13 patients with IUES (26 eyes) diagnosed by ophthalmology examination in Department of Ophthalmonogy of Beijing Tongren Hospital (IUES group) and 22 healthy people with 30 eyes (control group) were included in the study. Both eyes of all participants were examined by color Doppler ultrasound (CDU) and ultrasonic biomicroscopy (UBM). The thickness of the ocular wall at 300 μm on the temporal side of the optic disc was measured by CDU. UBM was used to measure the thickness of the nasal and temporal scleral processes. Corneal thickness (CT), anterior chamber depth (AD), lens thickness (LT) and axial length (AL) were measured by A-mode ultrasound. There were no significant differences in age (t=0.842), sex component ratio (χ2=0.540), eye difference (χ2=0.108) and AL (t=0.831) between IUES group and control group (P＞0.05). The CDU and UBM imaging features and biometrics of IUES affected eyes were observed. Independent sample t test was used for comparison between groups. ResultsCDU examination results showed that in 26 eyes of IUES group, choroidal detachment occurred in 20 eyes (76.9%, 20/26), which showed arc-shaped band echo connected with peripheral and equatorial eye wall echo, with uniform low echo area below, and blood flow signal could be seen on the band echo. The echo thickened and decreased in 4 eyes (15.3%, 4/26). Nine eyes (33.3%, 9/26) were accompanied by retinal detachment, which showed that the posterior pole vitreous echo was connected to the optic disc echo, and the blood flow signal was seen on the ribbon echo. UBM results showed ciliary detachment in 22 eyes (84.7%, 22/26), showing a spongy thickening of the ciliary body with interlamellar echo separation and an echoless area between the sclera. Ciliary body echo thickened and decreased in 2 eyes (7.7%, 2/26). Shallow space between ciliary body and sclera was observed in 2 eyes (7.7%, 2/26). Compared with the control group, CT (Z=2.054), LT (Z=1.867), scleral thickness (Z=2.536) and ocular wall thickness (Z=2.094) were thickened in IUES group, and AD (Z=1.888) were decreased, with statistical significance (P＜0.05). ConclusionsThe CDU of IUES is characterized by a thickened echo of the ocular wall and a uniform low echo area under the detached choroid. UBM is characterized by a spongy thickening of the ciliary body echo with interlaminar echo separation.
