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        find Keyword "Doppler" 52 results
        • Assessment of Liver Perfusion in Hepatitis Pregnant Women by Three-dimensinal-sonography Power Doppler Vascular Indexes

          ObjectiveTo evaluate liver perfusion in pregnant women with hepatitis between 13 and 41 weeks of gestation by three-dimensional color power Doppler angiography (3D-CPA) vascular indexes. MethodsThis study involved 73 pregnant women with hepatitis and 44 healthy pregnant women who had the pregnancy examination between February 2012 and June 2013. We sampled in the area which was near the right lobe of the pregnant women liver's portal vein branch, and obtained the vascularization index (VI), flow index (FI) and vascularization flow index (VFI) via the virtual organ computer-aided analysis (VOCAL) method. Then, we compared the liver perfusion differences between the pregnant women with hepatitis and healthy pregnant women. ResultsThe hepatic flow indexes obtained by 3D-CPA were significantly different between the HBV-DNA viral load and the control groups. The cutoff values of the three vascular indexes of patients with hepatitis with HBV-DNA viral load and the healthy pregnant women were respectively VI=8.760 (P<3×10-4); FI=22.180 (P<6×10-7); and VFI=1.575 (P<3×10-5). ConclusionApplication of the 3D-CPA on liver perfusion may differentiate pregnant women with hepatitis B from normal ones, thus offer a support for clinical prevention and treatment for pregnant women with hepatitis B.

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        • Application of high frequency color Doppler ultrasound combined with wide-field imaging in the preoperative navigation of anterolateral thigh perforator flap surgery

          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.

          Release date:2019-01-25 09:40 Export PDF Favorites Scan
        • Optimal template selecting combined with non-liner template matching for Doppler fetal heart rate extraction

          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.

          Release date:2019-08-12 02:37 Export PDF Favorites Scan
        • Present Status and Trend of Heart Fluid Mechanics Research Based on Medical Image Analysis

          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.

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        • Analysis of color Doppler flow imaging characteristics of vitreoretinal lymphoma

          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.

          Release date:2025-09-17 08:53 Export PDF Favorites Scan
        • Analysis of color Doppler flow imaging features of familial exudative vitreoretinopathy

          ObjectiveTo analyze the color Doppler flow imaging (CDFI) features of familial exudative vitreoretinopathy (FEVR) at different stages. MethodsA retrospective study. A total of 104 patients with 201 eyes from Department of Ophthalmology of Beijing Tongren Hospital who were hospitalized for fundus examination and diagnosed with FEVR from 2018 to 2022 were included. There were 69 male cases with 133 eyes and 35 female cases with 68 eyes. The age was ranged from 2 months to 11 years, with a mean age of 2.9 years. Fundus and CDFI examination were performed in both eyes. Fluorescein fundus angiography was performed in 72 cases (144 eyes). FEVR staging was conducted according to literature standards. The presence of avascular areas in the peripheral retina or abnormal retina neovascularization was stage 1; the presence of retinal neovascularization at the vitreoretinal interface in the avascular area was stage 2; partial retinal detachment without macula involvement was stage 3; partial retinal detachment involving the macula was stage 4; complete retinal detachment was stage 5. The CDFI ultrasound features of FEVR at different stages were analyzed. The CDFI image features of FEVR patients in different stages were observed. ResultsAmong the 104 patients, 97 (93.3%, 97/104) cases were binocular and 7 (6.7%, 7/104) cases were monocular. In 201 eyes, stages 1 to 5 of FEVR were 49 (24.4%, 49/201), 23 (11.4%, 23/201), 39 (19.4%, 39/201), 71 (35.3%, 71/201), and 19 (9.5%, 19/201) eyes, respectively. CDFI examination showed no abnormality or mild vitreous opacity in 49 eyes vitreous body at stage 1. Vitreous opacities were observed in all 23 eyes in stage 2, and the echo of the temporal ballwall was not smooth. In 39 eyes at stage 3, the anterior globular cluster echo in temporal peripheral eyes was observed in 17 eyes and partial retinal detachment was observed in 13 eyes. In 71 eyes at stage 4, 51 eyes had temporal or infratemporal retinal folds, and 20 eyes had temporal retinal detachment. All the 19 eyes in stage 5 had total retinal detachment, of which 15 eyes had closed "funnel-shaped" retinal detachment. Among the patients with retinal folds, 13 had bilateral folds, and the fellow eyes of the other 25 patients with unilateral folds all had vitreous opacity or clump echo in front of the temporal spherical wall. Blood flow signals could be detected on the retinal folds with Doppler imaging. ConclusionsThe CDFI manifestations of FEVR patients at different stages have different characteristics. The possibility of FEVR should be considered when the temporal or infratemporal retinal folds of both eyes are present, as well as the retinal folds of one eye, the contralateral vitreous body opacity, or the anterior temporal peribulbar cluster echoes are present.

          Release date:2025-02-25 09:39 Export PDF Favorites Scan
        • Ultrasound imaging manifestations of idiopathic uveal effusion syndrome

          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.

          Release date:2025-05-14 02:04 Export PDF Favorites Scan
        • Observation of choroidal blood flow and morphology in patients with severe stenosis of internal carotid artery

          Objective To observe the choroidal blood flow and morphological changes in patients with severe stenosis of internal carotid artery stenosis (ICAS). Methods A retrospective case-control study. Forty-six patients (46 eyes) with ICAS were enrolled in this study. There was severe stenosis in one side (the eyes in this side were set as case group) and mild or no stenosis in other side (the eyes in this side were set as control group). Color doppler ultrasound (CDI) was used to observe the changes of hemodynamic parameters of the ophthalmic artery (OA) and posterior ciliary artery (PCA), the main parameters of ultrasound Doppler imaging are peak systolic velocity (PSV), end diastolic velocity (EDV), resistance indices (RI) and the calculation of the pulsation indices (PI) through the use of a formula. Enhanced binarization of deep imaging coherence tomography (EDI-OCT) was used to measure the subfoveal choroidal thickness (SFCT). The total subfoveal choroidal area (TCA), luminal (LA), stromal (SA) and choroidal vascularity index (CVI) were obtained by modified image binarization technique. Results In the case group, the PSV in the OA and PCA was significantly lower than that of the control group (t=?2.200, ?2.612; P=0.030, 0.011). There were no significant differences in EDV, RI, PI of OA (t=0.337, ?1.810, ?1.848; P=0.737, 0.074, 0.068) and PCA (t=?1.160, 1.400, 0.815; P=0.249, 0.165, 0.417). The SFCT (t=?3.711, P<0.001), TCA (t=?2.736, P=0.007), LA (t=?3.188, P=0.002) and CVI (t=?2.096, P=0.039) of the case group was significantly lower than that of the control group. There were no significant differences in SA (t=?1.262, P=0.210) and LA/SA (t=?1.696, P=0.093). Conclusion In severe stenosis ICAS eyes, the PSV in the PCA and SFCT, TCA, LA, CVI are decreased.

          Release date:2018-01-17 03:16 Export PDF Favorites Scan
        • The clinical features of primary uveal lymphoma of four cases

          ObjectiveTo investigate the clinical, ophthalmological and pathological features of primary uveal lymphoma.MethodsRetrospective clinical study. From 2012 to 2018 in Beijing Tongren Eye Cener, 4 cases and 4 eyes of patients with primary uveal lymphoma were included in the study. Among them, 3 cases were male and 1 case was female. The average age was (54 ± 13.58) years old. The average time from initial diagnosis to pathological diagnosis was (18.50 ± 9.29) months. 3 cases were enucleated and 1 case was biopsied. Extranodal marginal zone lymphoma (EMZL) of the mucosa associated lymphoid tissue (MALT) was confirmed by pathological examination. BCVA, fundus color photography, color Doppler ultrasound and orbital MRI were performed in all eyes. UBM, OCT, FFA and ICGA were performed in 2 eyes, 3 eyes, 3 eyes and 2 eyes respectively. The clinical, imaging and pathological changes were observed. Following up time was ≥ 6 months.ResultsAt the initial diagnosis, BCVA was 0.6, 0.02 and 0.01 in 1, 2 and 1 eye respectively. Choroid, ciliary body and iris were involved in 3 eyes, choroid in 1 eye. The fundus of the eyes showed infiltration of choroid in yellow and white color, and the lesions were beyond the vascular arch to the equator and peripheral areas. Color Doppler ultrasonography showed that choroidal diffuse thickening and extrascleral extension (ESE) which was the corresponding hypoechoic areas behind the sclera. Among them, ESE showed crescent thickening in 1 eye and nodular thickening in 3 eyes. UBM showed that the echo of ciliary body was thicken and the internal echo was decreased with the iris involved. OCT showed that RPE was wavy and local retinal neuroepithelial layer detached. FFA showed that the early lesions were mottled with strong and weak fluorescence, and the late fluorescence leakage. The posterior wall of the eyeball was thickened and enhanced in MRI.ConclusionThe clinical manifestations of uveal lymphoma are various, color Doppler ultrasound has characteristic manifestations and ESE of crescent or nodular thickening is valuable in diagnosis.

          Release date:2020-07-20 08:34 Export PDF Favorites Scan
        • Application of contrast-enhanced ultrasound-assisted superficial inferior epigastric artery perforator flap to repair oral and maxillofacial defects

          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.

          Release date:2020-11-27 06:47 Export PDF Favorites Scan
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          2. 射丝袜