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Ultrafast power Doppler imaging for ischemic encephalopathy:A case report
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作者 Li-Jie Huang Jian-Feng Jiao +2 位作者 Qiong He Jian-Wen Luo Yi Guo 《World Journal of Clinical Cases》 SCIE 2023年第31期7640-7646,共7页
BACKGROUND Severely elevated intracranial pressure due to various reasons,such as decreased cerebral perfusion,can lead to devastating neurological outcomes,such as brain herniation.Decompression craniectomy is a life... BACKGROUND Severely elevated intracranial pressure due to various reasons,such as decreased cerebral perfusion,can lead to devastating neurological outcomes,such as brain herniation.Decompression craniectomy is a life-saving procedure that is commonly performed for such a critical situation,but the changes in cerebral microvessels after brain herniation and decompression are unclear.Ultrafast power Doppler imaging(uPDI)is a new microvascular imaging technology that utilizes high frame rate plane/diverging wave transmission and advanced clutter filters.uPDI significantly improves Doppler sensitivity and can detect microvessels,which are usually invisible using traditional ultrasound Doppler imaging.CASE SUMMARY In this report,uPDI was used for the first time to observe the brain blood flow of a hypoperfusion area in a 4-year-old girl who underwent decompression craniectomy due to refractory intracranial hypertension(ICP)after malignant brain tumor surgery.B-mode imaging was used to verify the increased densities of the cerebral cortex and basal ganglia that were observed by computed tomography.CONCLUSION uPDI showed the local blood supplies and anatomical structures of the patient after decompressive craniectomy.uPDI is potentially a more intuitive and noninvasive method for evaluating the effects of severe ICP on cerebral microvessels. 展开更多
关键词 Decompression craniectomy Ultrafast power doppler imaging Cortical layer necrosis Luxury perfusion Case report
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Hemodynamic Changes on Color Doppler Flow Imaging and Intravenous Contrast-enhanced Ultrasound for Assessing Transplanted Liver and Early Diagnosis of Complications 被引量:1
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作者 黄道中 陈云超 +1 位作者 李开艳 张青萍 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2008年第3期284-286,共3页
The value of color Doppler flow imaging (CDFI) and intravenous contrast-enhanced ultrasound (CEUS) for assessing the transplanted liver and early diagnosing complications by examining hemodynamic changes was discu... The value of color Doppler flow imaging (CDFI) and intravenous contrast-enhanced ultrasound (CEUS) for assessing the transplanted liver and early diagnosing complications by examining hemodynamic changes was discussed. Seventy-five patients with orthotopic liver transplantation (OLT) underwent CDFI. The following parameters were measured: peak systolic velocity (PS), resistance index (RI) and Doppler perfusion index (DPI) of the hepatic artery (HA), time average velocity (TAV) of portal vein (PV) and velocity of hepatic vein (HV) in different stages postoperation, And 11 patients of them received CEUS. Thirty healthy subjects were enrolled as controls, The results showed that: (1) In 23 patients without obvious complications, TAV of PV within 15 days post-operation was significantly higher than in controls (P〈0.05), PS and DPI of HA within 7 days postoperation were lower, but RI was higher than in controls (P〈0.05); (2) When the hepatic artery thrombosis (HAT) occurred, PS and DPI of HA were obviously decreased, but TAV of PV significantly increased like a high saw-tooth wave; (3) While rejection occurred, both TAV of PV and PS of HA were decreased with the increase in RI of HA, and the triphasic wave of HV disappeared and displayed as saw-tooth wave; (4) The incidence of biliary complications in liver transplantation was increased when DPI was reduced; (5) Seven cases of hepatic carcinoma relapse after OLT demonstrated hyperecho in the arterial phase and hypoecho in the portal and later phase on CEUS; (6) In 2 cases of HA thrombus, there was no visualized enhancement in arterial phase of CEUS, but enhancement during the portal vein and parenchymal phase. It was concluded that the hemodynamic changes of PV, HA and HV in the transplanted liver are valuable for assessing the transplanted liver and early diagnosing complications on CDFI and CEUS. 展开更多
关键词 color doppler flow imaging liver transplantation HEMODYNAMICS postoperative complications intravenous contrast-enhanced ultrasound
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Antidiastole Value of Three-dimensional Ultrasonography and Power Doppler between Uterine Parenchyma Lumps and Endometrial Cancer:A Retrospective Study 被引量:11
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作者 Yan ZHANG Jing CHEN +1 位作者 Zeng ZHEN Xiao-yan XU 《Current Medical Science》 SCIE CAS 2019年第5期816-819,共4页
Sometimes endometrial polyps,submucosal myomas,and endometrial cancer show similar findings under ultrasonography.The aim of this study was to assess the antidiastole value of blood flow parameters using three-dimensi... Sometimes endometrial polyps,submucosal myomas,and endometrial cancer show similar findings under ultrasonography.The aim of this study was to assess the antidiastole value of blood flow parameters using three-dimensional(3D)power Doppler ultrasonography angiography(PDA)between endometrial cancer and uterine parenchyma lumps.The data of the blood flow indices in 3D-PDA including the vascularization index(VI),flow index(FI),and vascularization flow index(VFI)in 40 patients with endometrial cancer and 41 patients with uterine parenchyma lumps(endometrial polyps and submucosal myomas)were retrospectively analysed and compared utilizing Virtual Organ Computer-aided AnaLysis(VOCAL)software.The results showed that all the blood flow parameters(VI,FI,VFI)were significantly higher in women with endometrial cancer than in those with uterine parenchyma lumps(P<0.001).The area under the curve of ROC of VI,FI,and VFI was 0.98,0.84,and 0.97,respectively.Thus,the best predictor of endometrial carcinoma was VI with a sensitivity of 97.0% and a specificity of 91.0%.The optimal cutoff value of VI was 4.06%.Our data demonstrated that all of the blood flow signal parameters(including VI,FI,and VFI)in 3D power Doppler ultrasonography had significant antidiastole values between endometrial cancer and uterine parenchyma lumps to assist clinicians in properly diagnosing patients. 展开更多
关键词 power doppler three-dimensional ultrasound UTERINE PARENCHYMA lump ENDOMETRIAL CARCINOMA BLOOD flow signal parameter
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Power Doppler ultrasonographic assessment of the ankle in patients with inflammatory rheumatic diseases 被引量:1
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作者 Takeshi Suzuki 《World Journal of Orthopedics》 2014年第5期574-584,共11页
Ankle involvement is frequent in patients with inflammatory rheumatic diseases, but accurate evaluation by physical examination is often difficult because of the complex anatomical structures of the ankle. Over the la... Ankle involvement is frequent in patients with inflammatory rheumatic diseases, but accurate evaluation by physical examination is often difficult because of the complex anatomical structures of the ankle. Over the last decade, ultrasound(US) has become a practical imaging tool for the assessment of articular and periarticular pathologies, including joint synovitis, tenosynovitis, and enthesitis in rheumatic diseases. Progress in power Doppler(PD) technology has enabled evaluation of the strength of ongoing inflammation. PDUS is very useful for identifying the location and kind of pathologies in rheumatic ankles as well as for distinguishing between inflammatory processes and degenerative changes or between active inflammation and residual damage. The aim of this paper is to illustrate the US assessment of ankle lesions in patients with inflammatory rheumatic diseases, including rheumatoid arthritis, spondyloarthritis, and systemic lupus erythematosus, focusing on the utility of PDUS. 展开更多
关键词 ANKLE power doppler Ultrasound RHEUMATOID ARTHRITIS Psoriatic ARTHRITIS SPONDYLOARTHRITIS TENOSYNOVITIS ENTHESITIS
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Correlation between Perifollicular Vascularity and Outcome in Stimulated Intrauterine Insemination Treatment Cycles: A Study Using Two-Dimensional Transvaginal Power Doppler Ultrasound
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作者 Nadia M. Madkour Wael S. Nossair +3 位作者 Essa M. Arafa Amany M. Abdelghany Ekramy A. Mohamed Walid A. Abdelsalam 《Open Journal of Obstetrics and Gynecology》 2014年第15期973-980,共8页
Objective:?The aim of this study is to assess any potential relationship between perifollicular vascularity and occurrence of pregnancy in cases of stimulated IUI cycles using the subjective grading system by 2D trans... Objective:?The aim of this study is to assess any potential relationship between perifollicular vascularity and occurrence of pregnancy in cases of stimulated IUI cycles using the subjective grading system by 2D transvaginal power Doppler ultrasonography.?Design: A prospective cross sectional cohort study. Method: This is a prospective cross-sectional cohort study of 90 stimulated IUI treatment cycles. Selected women were prescribed clomiphene citrate combined with highly purified urinary follicle stimulating hormone. All patients underwent serial transvaginal ultrasound scans starting from day 6 to 7 of the cycle. Perifollicular Doppler blood flows were assessed in dominant follicles ≥18 mm. The patients then were categorized into 3 groups (high vascularity group {G3 & G4}, low vascularity group {G1 & G2} and mixed grades group). Other parameters measured included number of follicles ≥ 18 mm in both ovaries, endometrial thickness and estradiol (E2) level . Human chorionic gonadotropin (hCG) injection 10,000 IU IM was given to the patient when the dominant follicle reached 18 mm in diameter. At that time, the endometrium was evaluated as regards endometrial thickness. IUI was carried out using prepared/“washed” semen (husband). All patients received luteal support in the form of progesterone from day of IUI for 14 days. Serum Β-hCG was estimated 2 weeks after insemination. Results: In this study, from all 90 cases only 8 cases got pregnant with pregnancy rate of 8.88% (6 cases got pregnant in high grade vascularity group;2 cases in mixed grades group and no cases got pregnant?in low grade group). There was statistically significant difference among the 3 groups as regarding?the pregnancy rate (P value = 0.02). There is statistically significant difference in perifollicular resistance index (RI) and pulsatility index (PI) between pregnant and non pregnant cases (P value = 0.016 and 0.047 respectively). In this study, there is no statistically significant difference between pregnant and non pregnant cases as regarding endometrial thickness and E2 level at the day of hCG administration (P value = 0.39 and 0.76 respectively). Conclusion: Perifollicular blood-flow assessment by 2D transvaginal power Doppler is a good predictive for the outcome of stimulated IUI cycles. 展开更多
关键词 Perifollicular VASCULARITY IUI 2D power doppler Ultrasound
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Preoperative serum vascular endothelial growth factor correlated to three dimensional power Doppler indices in ovarian masses
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作者 Maged R. AbouSeeda Ghada M. Mansour Sahar S. Ez-Elarab 《Open Journal of Obstetrics and Gynecology》 2014年第3期112-119,共8页
Objective: To assess the preoperative serum levels of vascular endothelial growth factor (VEGF) in ovarian masses compared to normal controls and to find a correlation between VEGF and Doppler indices in ovarian masse... Objective: To assess the preoperative serum levels of vascular endothelial growth factor (VEGF) in ovarian masses compared to normal controls and to find a correlation between VEGF and Doppler indices in ovarian masses. Methods: The study was conducted from December 2009 to September 2012 in the oncology and ultrasound units in department of obstetrics and gynecology, Ain Shams University on 150 patients with ovarian masses. During preoperative workup, serum Ca-125 levels and serum VEGF levels were obtained. Ultrasonographic examination included two and three dimensional power Doppler ultrasound (3DPD). Laparotomic approaches were undertaken to obtain the final pathologic results. VEGF was measured in one hundred normal cases as controls. Results: Final ovarian pathology revealed seventy three malignant ovarian masses and seventy seven were benign. Serum Ca-125 levels in malignant cases were higher compared to those in benign cases (p < 0.001). Preoperative serum VEGF revealed higher levels in malignant ovarian masses than benign conditions and normal controls (p < 0.001). Three dimensional power Doppler indices, vascularization index (VI), flow index (FI) and vascularization flow index (VFI), correlated positively with serum VEGF levels. Conclusion: Preoperative serum VEGF revealed higher levels in malignant ovarian masses than benign conditions and normal controls. These levels positively correlated with the Doppler vascular indices of the masses. 展开更多
关键词 OVARIAN Cancer OVARIAN Mass Three DIMENSIONAL power doppler VEGF VI FI VFI
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Changes in three-dimensional power Doppler ultrasound features before and after neoadjuvant chemotherapy for cervical cancer and their relationship with malignant molecule expression
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作者 Ju-Hua Pan Ye-Qing Ren Qing-Lian Ma 《Journal of Hainan Medical University》 2019年第11期69-74,共6页
Objective:To study the changes in three-dimensional power Doppler ultrasound features before and after neoadjuvant chemotherapy for cervical cancer and their relationship with malignant molecule expression.Methods: Th... Objective:To study the changes in three-dimensional power Doppler ultrasound features before and after neoadjuvant chemotherapy for cervical cancer and their relationship with malignant molecule expression.Methods: The patients who were diagnosed with cervical cancer and received neoadjuvant chemotherapy in Wuhan Red Cross Hospital between March 2015 and October 2017 were selected as the cervical cancer group, and the patients who received cervical biopsy and were diagnosed with stage I cervical intraepithelial neoplasia by pathological findings during the same period were selected as the control group. Before biopsy, three-dimensional power Doppler ultrasonography was performed to measure VI, FI and VFI;the tissues of cervical cancer group before and after chemotherapy as well as the biopsy tissues of control group were collected to measure the expression of proliferation genes, invasion genes and angiogenesis genes.Results: The VI, FI and VFI levels as well as the Piwil2 gene (Piwil2), CyclinD1, N-Myc downstream regulated gene 3 (NDRG3), CXC chemokine ligand 5 (CXCL5), cathepsin-L (CAT-L), EGF-containing fibulin-like extracellular matrix protein 1 (EFEMP1), angiotensin (Ang)1, Ang2 and angiopoietin-like protein 4 (ANGPTL4) mRNA expression levels in the tissues of cervical cancer group before and after chemotherapy were all significantly higher than those of control group whereas the thrombospondin 2 (THBS2), Smac gene (Smac), large tumor suppressor kinase 1 (LATS1), reversion-inducing-cysteine-rich protein with kazal motifs (RECK) and plas minogen activator inhibitor 1 (PAI-1) mRNA expression levels in the tissues were all significantly lower than those of control group, and the VI, FI and VFI levels as well as the Piwil2, CyclinD1, NDRG3, CXCL5, CAT-L, EFEMP1, Ang1, Ang2 and ANGPTL4 mRNA expression levels in the tissues of cervical cancer group after chemotherapy were all significantly lower than those before chemotherapy whereas the THBS2, Smac, LATS1, RECK and PAI-1 mRNA expression levels were all significantly higher than those before chemotherapy;the VI, FI and VFI levels in cervical cancer tissues were positively correlated with the Piwil2, CyclinD1, NDRG3, CXCL5, CAT-L, EFEMP1, Ang1, Ang2 and ANGPTL4 mRNA expression levels, and negatively correlated with the THBS2, Smac, LATS1, RECK and PAI-1 mRNA expression levels.Conclusion: The changes in the three-dimensional power Doppler ultrasound parameters before and after neoadjuvant chemotherapy for cervical cancer can reflect the changes in proliferation, invasion and angiogenesis gene expression in the lesions. 展开更多
关键词 CERVICAL cancer Three-dimensional power doppler ultrasound Proliferation INVASION ANGIOGENESIS
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Comparative Study of Radiological Changes in Hands and Feet in Patients Suffering from Early Rheumatoid Arthritis by Power Doppler Ultrasound and Direct Digital Radiography
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作者 Gargy Mondal Biswadip Ghosh +1 位作者 Manoranjan Ghosh Pampa Halder 《Open Journal of Rheumatology and Autoimmune Diseases》 2014年第1期39-42,共4页
Rheumatoid arthritis is a chronic multisystem disease of unknown cause. The characteristic feature of RA is persistent inflammatory synovitis. The natural history of disease is such that the early months of the diseas... Rheumatoid arthritis is a chronic multisystem disease of unknown cause. The characteristic feature of RA is persistent inflammatory synovitis. The natural history of disease is such that the early months of the disease are critical period during which reversible joint damage occurs. So early diagnosis of RA and appropriate drug application is the only way to save a patient from this crippling disease. In India, the cost of investigations is a significant factor for most of the patients. Ultrasonography or Power Doppler Ultra Sound (PDUS) has the advantage of being economic in spite of its sensitivity in assessing both inflammatory and destructive changes. The aim of the present study was to evaluate the diagnostic efficiency of PDUS in early rheumatoid arthritis. The study was performed with the patients attending Rheumatology Clinic. A total number of 106 patients of clinically suspected rheumatoid arthritis were studied as per selection criteria. Radiological examinations of hands were done by digital radiography and PDUS in a group of 53 patients, assessment of foot changes by PDUS and Digital Radiography were done in another similar group of 53 patients. Final diagnosis by ACR EULAR-2010 criteria is done for all the patients. The comparative study reveals that synovial vascularity as demonstrated by PDUS is much more effective in diagnosing early rheumatoid arthritis, both in hand and in feet than digital radiograph. PDUS of feet may yield earlier and better findings than hands, which is conventionally used in patients suffering from early rheumatoid arthritis. 展开更多
关键词 R.A.—Rheumatoid Arthritis PDUS—power doppler Ultrasound D.R.—Digital Radiography ACR-EULAR—American College of RHEUMATOLOGY (ACR) and the European LEAGUE against RHEUMATISM (EULAR) RF—Rheumatoid Factor CRP—c-Reactive Protein MRI—Magnetic Resonance Imaging
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三维能量多普勒超声预测宫颈癌化疗效果的临床价值
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作者 陈高进 李瑞霞 冯菲 《临床超声医学杂志》 CSCD 2024年第6期471-474,共4页
目的探讨三维能量多普勒超声(3D-PDU)预测宫颈癌化疗效果的临床应用价值。方法选取在我院接受新辅助化疗治疗的宫颈癌患者160例,根据化疗效果分为有效组103例和无效组57例,比较两组3D-PDU血流参数[血管形成-血流指数(VFI)、血流指数(FI... 目的探讨三维能量多普勒超声(3D-PDU)预测宫颈癌化疗效果的临床应用价值。方法选取在我院接受新辅助化疗治疗的宫颈癌患者160例,根据化疗效果分为有效组103例和无效组57例,比较两组3D-PDU血流参数[血管形成-血流指数(VFI)、血流指数(FI)及血管形成指数(VI)]的差异。采用多因素Logistic回归分析筛选预测宫颈癌患者化疗效果的独立危险因素,并建立宫颈癌患者化疗效果风险预测模型;采用Hosmer-Lemeshow检验评估模型的拟合度;绘制受试者工作特征(ROC)曲线分析模型的预测效能。结果化疗后,两组VFI、FI及VI均较化疗前下降,且有效组上述参数均低于无效组,差异均有统计学意义(均P<0.05)。多因素Logistic回归分析显示,化疗后VFI、FI及VI均为预测宫颈癌患者化疗效果的独立危险因素(OR=2.826、4.637、3.216,均P<0.05),建立宫颈癌患者化疗效果风险预测模型为:Logit(P)=1/[1+e^((-4.609+1.039×化疗后VFI+1.534×化疗后FI+1.168×化疗后VI))]。Hosmer-Lemeshow检验显示模型的拟合度较好(χ^(2)=4.635,P=0.781);ROC曲线分析显示模型预测宫颈癌患者化疗效果的曲线下面积为0.882(P<0.05)。结论应用3D-PDU可以较好地预测宫颈癌化疗效果,具有一定的临床应用价值。 展开更多
关键词 超声检查 能量多普勒 三维 宫颈癌 化疗效果 预测模型
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经阴道三维能量多普勒超声联合二维剪切波弹性成像预测备孕女性妊娠结局的临床价值
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作者 冯菲 李瑞霞 +3 位作者 孟文玉 陈高进 张文霞 陈飞 《临床超声医学杂志》 CSCD 2024年第3期223-228,共6页
目的应用经阴道三维能量多普勒超声(3D-PDI)联合二维剪切波弹性成像(2D-SWE)评估备孕女性子宫内膜容受性,探讨其预测妊娠结局的临床应用价值。方法选取在我院接受卵泡检测的87例备孕女性,均于排卵第7~8天(种植窗期)行经阴道3D-PDI检查,... 目的应用经阴道三维能量多普勒超声(3D-PDI)联合二维剪切波弹性成像(2D-SWE)评估备孕女性子宫内膜容受性,探讨其预测妊娠结局的临床应用价值。方法选取在我院接受卵泡检测的87例备孕女性,均于排卵第7~8天(种植窗期)行经阴道3D-PDI检查,于增殖期行2D-SWE检查,然后随访6周,根据妊娠结局将其分为受孕组31例和未受孕组56例。比较两组子宫内膜厚度、容积、回声类型、血流分型、子宫螺旋动脉搏动指数(PI)、阻力指数(RI)、收缩期峰值流速与舒张末期流速比值(S/D)、血管化指数(VI)、血流指数(FI)、血管化血流指数(VFI),以及子宫内膜杨氏模量平均值(以下简称杨氏模量值)的差异。绘制受试者工作特征(ROC)曲线分析经阴道3D-PDI和2D-SWE参数单独及联合应用对备孕女性妊娠结局的预测价值。结果受孕组子宫内膜厚度和FI均高于未受孕组,S/D和子宫内膜杨氏模量值均低于未受孕组,差异均有统计学意义(均P<0.05);两组子宫内膜容积、回声类型、血流分型及PI、RI、VI、VFI比较差异均无统计学意义。ROC曲线分析显示,子宫内膜厚度、FI、S/D和子宫内膜杨氏模量值预测备孕女性妊娠结局的曲线下面积分别为0.789、0.851、0.853和0.840,联合应用的曲线下面积为0.895,高于各参数单独应用,差异均有统计学意义(均P<0.05)。结论经阴道3D-PDI联合2D-SWE可准确评估备孕女性子宫内膜容受性,对预测其妊娠结局有较好的临床应用价值。 展开更多
关键词 超声检查 经阴道 能量多普勒 三维 剪切波弹性成像 二维 备孕女性 子宫内膜容受性 妊娠结局
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超声评分法联合三维能量多普勒血流灌注参数对胎盘植入性疾病的诊断价值
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作者 袁红梅 许聃 +1 位作者 张丽 孙广宏 《宁夏医科大学学报》 2024年第9期931-934,944,共5页
目的探讨超声评分法联合三维能量多普勒超声(3D power doppler ultrasonography,3D-PDU)诊断胎盘植入性疾病(placenta accreta,PAS)不同病理分型的应用价值。方法分析112例疑似PAS的孕妇,术前进行超声评分,并进行3D-PDU检查,测量血管指... 目的探讨超声评分法联合三维能量多普勒超声(3D power doppler ultrasonography,3D-PDU)诊断胎盘植入性疾病(placenta accreta,PAS)不同病理分型的应用价值。方法分析112例疑似PAS的孕妇,术前进行超声评分,并进行3D-PDU检查,测量血管指数(vascularization index,VI)、血流指数(flow index,FI)和血管-血流指数(vascularization flow index,VFI)。以病理诊断为金标准将样本分为不同组别,比较组间血流灌注参数的差异性。结果112例疑似PAS患者病理证实92例,PAS组VI、FI及VFI均高于无PAS组(P均<0.05)。92例PAS中未侵入肌层即粘连型24例,侵入肌层包括植入型和穿透型68例,侵入肌层组的VI、FI及VFI均高于非侵入肌层组(P均<0.05)。而植入型与穿透型比较时,穿透型的VI、VFI均高于植入型(P均<0.05)。采用超声评分法联合3D-PDU诊断粘连型、植入型以及穿透型胎盘植入的Kappa值分别为0.724、0.856和0.892。结论超声评分法与3D-PDU联合使用可定量分析胎盘血流灌注情况,为产前诊断PAS的精准分型提供量化评估依据。 展开更多
关键词 胎盘植入性疾病 三维能量多普勒超声 超声评分法
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早孕期三维能量多普勒联合频谱多普勒定量评估胎盘血流灌注预测胎儿生长受限的相关性 被引量:2
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作者 汤倩 姜海娜 +1 位作者 韩宏霞 邓金凤 《中国实验诊断学》 2024年第2期173-178,共6页
目的 分析早孕期三维能量多普勒联合频谱多普勒定量评估胎盘血流灌注预测胎儿生长受限(FGR)的相关性。方法 选取76例于天津中医药大学附属北辰中医医院2021年4月—2022年9月进行早孕期NT检查的孕妇为研究对象,根据胎儿是否存在生长受限... 目的 分析早孕期三维能量多普勒联合频谱多普勒定量评估胎盘血流灌注预测胎儿生长受限(FGR)的相关性。方法 选取76例于天津中医药大学附属北辰中医医院2021年4月—2022年9月进行早孕期NT检查的孕妇为研究对象,根据胎儿是否存在生长受限分为对照组69例,FGR组7例。以此对比产妇基本资料,两组超声参数:胎盘血管化指数(VI)、胎盘血流指数(FI)、血管化-血流指数(VFI)、子宫动脉阻力指数(UtA-RI)、子宫动脉搏动指数(UtA-PI)、胎儿静脉导管搏动指数(DV-PI),分析发生FGR独立危险因素,超声参数与FGR的相关性,ROC曲线分析不同指标预测FGR的效能。结果 FGR与年龄、BMI指数、孕期贫血、产次无关,无统计学差异(P>0.05);主要与胎膜早破、羊水过少、脐带异常、胎粪污染、胎盘异常有关,具有统计学差异(P<0.05)。与对照组相比,FGR组VI、VFI、水平较低,UtA-RI、UtA-PI、DV-PI水平有所提升(P<0.05)。以FGR为因变量(0=否,1=是),建立Logistic回归模型,结果显示,VI、VFI、UtA-RI、UtA-PI、DV-PI是导致FGR的独立危险因素(P<0.05)。VI、VFI参数与FGR呈负相关;UtA-RI、UtA-PI、DV-PI参数与FGR呈正相关(P<0.05)。ROC曲线显示,VI、VFI、UtA-RI、UtA-PI、DV-PI单一及联合预测均有较高效能,而联合检查预测价值最高(P<0.05)。结论 早孕期采用三维能量多普勒联合频谱多普勒预测FGR的效能较高,有助于早期诊断并及时采取干预措施。 展开更多
关键词 胎儿生长受限 三维能量多普勒 频谱多普勒 胎盘血流灌注 相关性
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三维能量多普勒定量技术对乳腺癌组织学分级的预测价值探讨
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作者 葛丹 姚洁 +2 位作者 姚春 江婷 欧斐 《浙江医学》 CAS 2024年第10期1083-1086,I0004,共5页
目的探讨三维能量多普勒超声(3D-PDUS)中血管定量参数对乳腺癌组织学分级的预测价值。方法回顾性选择2018年1月至2023年6月在杭州市中医院行手术治疗的乳腺癌患者77例(恶性肿块86个),所有肿块均经病理组织学检查证实,根据组织学分级分... 目的探讨三维能量多普勒超声(3D-PDUS)中血管定量参数对乳腺癌组织学分级的预测价值。方法回顾性选择2018年1月至2023年6月在杭州市中医院行手术治疗的乳腺癌患者77例(恶性肿块86个),所有肿块均经病理组织学检查证实,根据组织学分级分为Ⅰ级组、Ⅱ级组、Ⅲ级组。比较3组患者年龄、常规超声检查所见、3D-PDUS指标。常规超声检查所见包括淋巴结转移、肿块内部钙化、肿块Adler血流分级;3D-PDUS指标包括肿块体积、血管参数[血管形成指数(VI)、血流指数(FI)、血管形成-血流指数(VFI)]。应用logistic回归分析乳腺癌组织学分级的危险因素。采用ROC曲线分析VI、FI、VFI对乳腺癌组织学分级的预测准确度。结果Ⅲ级组VI、FI、VFI高于Ⅱ级组,Ⅱ级组高于Ⅰ级组,差异均有统计学意义(均P<0.05)。其中FI为乳腺癌不同组织学分级的独立危险因素(P<0.001)。ROC曲线分析显示VI、FI、VFI对乳腺癌组织学分级的预测准确度均较高(AUC=0.888、0.891、0.894,均P<0.001)。结论3D-PDUS显示的VI、FI、VFI是瘤内血管化重要定量指标,可为乳腺癌患者组织学分级提供可靠的影像学预测信息。 展开更多
关键词 三维能量多普勒超声 乳腺癌 组织学分级 超声 病理
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融合卫星姿态的星地信道建模及硬件模拟
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作者 周强军 吕崇玉 +3 位作者 陈小敏 华博宇 台鑫 朱秋明 《信号处理》 CSCD 北大核心 2024年第6期1019-1029,共11页
针对传统星地信道模型及其硬件模拟方法没有考虑卫星姿态对信道特性影响的问题,本文基于几何地理随机模型(Geometry-based Stochastic Model,GBSM)框架,提出了一种融合卫星姿态的星地信道模型。该模型通过构建四个独立的坐标系并引入姿... 针对传统星地信道模型及其硬件模拟方法没有考虑卫星姿态对信道特性影响的问题,本文基于几何地理随机模型(Geometry-based Stochastic Model,GBSM)框架,提出了一种融合卫星姿态的星地信道模型。该模型通过构建四个独立的坐标系并引入姿态修正矩阵,来描述卫星姿态变化对星地信道特性造成的影响。在此基础上,本文基于现场可编程门阵列(Field Programmable Gate Array,FPGA),设计并研制了一种星地信道硬件模拟器。硬件模拟器采用差分迭代的算法来生成信道衰落因子,可以极大提高硬件模拟的实时性,确保生成的衰落数据与实际场景相匹配。同时,还采用了并行处理架构,可以支持最大640 MHz带宽的星地信道模拟。为了将衰落数据与并行架构相匹配,引入了并行内插算法,可以将串行的衰落数据内插成同速率的多路并行衰落数据。此外,为了能够精准控制硬件装置输出信号的功率,设计了基于预训练的功率校正方法。通过内部校正源信号预先训练出整个模拟过程给信号带来的增益再进行功率补偿,从而保证输出信号的功率可以被精准控制。最后,在典型场景下开展仿真模拟,导出硬件模拟器的输出结果并分析其统计特性,结果表明实测输出的概率密度函数(Probability Density Function,PDF)和多普勒功率谱密度(Doppler Power Spectral Density,DPSD)与理论值吻合,证明本文设计的硬件模拟器可以准确地复现实际场景下卫星姿态发生变化的星地信道。本文提出的融合卫星姿态的星地信道模型以及研制的硬件模拟器很好地解决了传统模型以及硬件模拟方法的局限性,在卫星通信系统的优化、评估和验证环节具有极大的潜在价值。 展开更多
关键词 星地信道模型 信道模拟 姿态修正矩阵 多普勒功率谱
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三维能量多普勒超声预测子宫腺肌病患者体外受精-胚胎移植后妊娠结局的临床价值
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作者 王付敏 申向辉 +2 位作者 安利香 张欢 尹素芳 《临床超声医学杂志》 CSCD 2024年第9期730-734,共5页
目的探讨经阴道三维能量多普勒超声(3D-PDUS)预测子宫腺肌病患者体外受精-胚胎移植(IVF-ET)后妊娠结局的临床价值。方法选取在我院接受IVF-ET的子宫腺肌病不孕患者100例(研究组),以及同期单纯不孕患者40例(对照组),均于IVF-ET前行经阴道... 目的探讨经阴道三维能量多普勒超声(3D-PDUS)预测子宫腺肌病患者体外受精-胚胎移植(IVF-ET)后妊娠结局的临床价值。方法选取在我院接受IVF-ET的子宫腺肌病不孕患者100例(研究组),以及同期单纯不孕患者40例(对照组),均于IVF-ET前行经阴道3D-PDUS观察子宫内膜与肌层交界区(EMI)的形态,获取EMI平均厚度、容积及血管化指数(VI)、血流指数(FI)、血管化血流指数(VFI),比较两组上述参数的差异。记录研究组患者妊娠结局,比较妊娠患者与未妊娠患者EMI形态、平均厚度、容积及VI、FI、VFI的差异。采用二元Logistic回归分析筛选子宫腺肌病患者IVF-ET后妊娠结局的独立影响因素;绘制受试者工作特征(ROC)曲线分析经阴道3D-PDUS预测子宫腺肌病患者IVF-ET后妊娠结局的诊断效能。结果研究组EMI形态正常占比、FI均低于对照组,差异均有统计学意义(均P<0.05);两组EMI平均厚度、容积及VI、VFI比较差异均无统计学意义。研究组患者接受IVF-ET后成功妊娠60例,未妊娠40例;妊娠患者EMI形态正常占比、平均厚度、容积及VI、FI、VFI均高于未妊娠患者,差异均有统计学意义(均P<0.001)。二元Logistic回归分析显示,EMI容积和VFI均为子宫腺肌病患者IVF-ET后妊娠结局的独立影响因素(OR=4.725、2.160,均P<0.05)。ROC曲线分析显示,EMI容积和VFI预测子宫腺肌病患者IVF-ET后妊娠结局的曲线下面积分别为0.795和0.672,对应的截断值分别为3.085 cm3和0.597。结论经阴道3D-PDUS能较好地预测子宫腺肌病患者IVF-ET后妊娠结局,具有一定的临床价值。 展开更多
关键词 超声检查 三维 经阴道 能量多普勒 子宫腺肌病 体外受精-胚胎移植 妊娠结局
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OFDM通信系统中的一种最大Doppler频移估计算法 被引量:1
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作者 蔡玮 朱光喜 +1 位作者 张青春 李黎 《通信学报》 EI CSCD 北大核心 2005年第11期112-116,124,共6页
在分析了已有各种Doppler估计算法的基础上,根据功率谱估计经典算法——窗函数法的原理,直接利用接收到的频域中连续导频信号,进行最大Doppler频移估计。该算法同时适合于单载波和多载波系统。仿真结果均表明:在单径和多径条件下,该算... 在分析了已有各种Doppler估计算法的基础上,根据功率谱估计经典算法——窗函数法的原理,直接利用接收到的频域中连续导频信号,进行最大Doppler频移估计。该算法同时适合于单载波和多载波系统。仿真结果均表明:在单径和多径条件下,该算法均可对正交频分复用(OFDM)传输系统中的最大Doppler频移获得较精确的估计结果。该算法十分适合于OFDM移动通信系统。 展开更多
关键词 最大doppler频移 正交频分复用 功率谱 窗函数
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ADNEX模型联合三维能量多普勒超声鉴别卵巢肿瘤良恶性的价值
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作者 刘醒 张又红 林宇佳 《中国医药科学》 2024年第19期140-143,188,共5页
目的探讨评估不同附件肿瘤(ADNEX)模型联合三维能量多普勒超声(3D-PDUS)鉴别卵巢肿瘤良恶性的临床应用价值。方法回顾性收集2022年10月至2023年6月于梅州市人民医院接受手术治疗并于术前进行过二维及三维超声检查的64例卵巢肿瘤患者的6... 目的探讨评估不同附件肿瘤(ADNEX)模型联合三维能量多普勒超声(3D-PDUS)鉴别卵巢肿瘤良恶性的临床应用价值。方法回顾性收集2022年10月至2023年6月于梅州市人民医院接受手术治疗并于术前进行过二维及三维超声检查的64例卵巢肿瘤患者的67个肿块,根据病理学分为良性组(40个)和恶性组(27个),分别进行ADNEX模型分析;比较良恶性卵巢肿瘤组间的3D-PDUS血流参数差异,筛选有意义的指标,并据此对ADNEX模型的诊断结果进行升级或降级;分别绘制ADNEX模型及联合3D-PDUS后诊断卵巢肿瘤的ROC曲线,比较ADNEX模型及联合3D-PDUS诊断卵巢肿瘤良恶性的价值。结果恶性组3D-PDUS的血管指数(VI)及血管-血流指数(VFI)值均高于良性组,差异有统计学意义(P<0.05);根据VI及VFI值对卵巢肿瘤的分级进行调整后,病理性质为良性的卵巢肿瘤中有8个被正确下调为良性,2个被错误上调为恶性;病理为恶性的卵巢肿瘤中有2个被错误下调为良性,1个被正确上调为恶性。ADNEX模型的AUC值为0.751(95%CI:0.631~0.871),敏感度为85.2%,特异度为65.0%,阳性预测值为62.2%,阴性预测值为86.7%;联合3D-PDUS后,AUC值为0.826(95%CI:0.719~0.932),敏感度为85.2%,特异度为80.0%,阳性预测值为74.2%,阴性预测值为88.9%,除敏感度外,各项诊断指标均有所提高。结论ADNEX模型联合3D-PDUS技术能更好地鉴别卵巢肿瘤的良恶性,在不降低敏感度的情况下,提升诊断特异度。 展开更多
关键词 评估不同附件肿瘤模型 三维能量多普勒超声 卵巢肿瘤 超声检查
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超声超微血流多普勒评估子宫内膜容受性及预测辅助生殖技术妊娠结局的价值:一项病例对照研究
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作者 宋梦洁 徐虹 汪龙霞 《解放军医学院学报》 CAS 2024年第8期832-838,846,共8页
背景子宫内膜区域血流量是评价内膜容受性的重要指标,目前临床上缺少一种可有效定量分析子宫内膜血流量的超声评价指标。目的探讨MV-Flow超声成像技术下接受辅助生殖技术的育龄期不孕女性子宫内膜容受性指标特点及其对辅助生殖妊娠结局... 背景子宫内膜区域血流量是评价内膜容受性的重要指标,目前临床上缺少一种可有效定量分析子宫内膜血流量的超声评价指标。目的探讨MV-Flow超声成像技术下接受辅助生殖技术的育龄期不孕女性子宫内膜容受性指标特点及其对辅助生殖妊娠结局的预测能力。方法选取2022年5—12月于解放军总医院第一医学中心行经阴道盆腔妇科超声检查且接受辅助生殖技术的育龄期不孕女性为研究对象,以同期行相同检查的健康育龄期女性为对照组,两组均采用MV-Flow超声成像技术分析并比较子宫内膜相关参数差异。追访不孕组行辅助生殖技术后的妊娠结局,并评价MV-Flow超声成像技术对预测成功妊娠的价值。结果接受辅助生殖技术不孕组59例,年龄(35.41±4.89)岁;健康对照组62例,年龄(33.10±5.09)岁。不孕组年龄高于健康对照组,差异有统计学意义(P=0.012)。健康对照组子宫内膜厚度[M(IQR):0.9(0.7~1.0)cm vs 0.8(0.6~0.9)cm]、体积[M(IQR):3.71(2.66~5.10)mL vs 2.90(2.03~3.99)mL]、三维能量血流指数(flow index,FI)[(27.88±10.33)dB vs(23.84±10.42)dB]、微血流血管化指数(microvascular bleeding vascularization index,VI_(MV))[M(IQR):12.20%(5.15%~19.36%)vs 7.13%(3.08%~14.12%)]均高于不孕组,差异有统计学意义(P<0.05)。根据妊娠结局分为妊娠组29例,年龄(33.43±3.95)岁,未妊娠组30例,年龄(37.66±5.01)岁,两组年龄差异有统计学意义(P=0.009)。妊娠组女性的内膜三维能量FI[(28.88±7.92)dB vs(18.54±10.27)dB]、VI_(MV)[M(IQR):13.42%(5.45%~16.99%)vs 5.16%(2.17%~7.73%)]和抗米勒管激素(anti-Müllerian hormone,AMH)[M(IQR):2.49(1.24~6.05)ng/mL vs 1.61(0.80~2.49)ng/mL]高于未妊娠组,差异有统计学意义(P<0.05)。子宫内膜VIMV对预测成功妊娠的曲线下面积为0.794,VI_(MV)分别联合年龄、FI、AMH、综合评价指标1(F1)以及四者的排列组合预测妊娠结局的曲线下面积为0.815~0.871,其中子宫内膜VI_(MV)联合年龄、FI和F1的曲线下面积最大(AUC=0.871)。结论MV-Flow超声成像技术能够为接受辅助生殖技术预测成功妊娠提供影像学参考。 展开更多
关键词 MV-Flow成像技术 微血流成像 辅助生殖技术 子宫内膜容受性 三维能量多普勒.
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二维超声联合三维血管成像对慢性子宫内膜炎的诊断价值
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作者 周毛毛 刘玮 +2 位作者 杨洋 陈宥艺 刘莉 《中国妇幼健康研究》 2024年第4期32-37,共6页
目的 探讨经阴道二维超声联合三维能量多普勒血管成像(3D-PDA)检查子宫内膜对慢性子宫内膜炎(CE)的诊断价值。方法 选取2023年1月至2023年8月西安市第四医院收治的210例女性患者作为研究对象,均行经阴道超声及宫腔镜检查,以病理诊断结... 目的 探讨经阴道二维超声联合三维能量多普勒血管成像(3D-PDA)检查子宫内膜对慢性子宫内膜炎(CE)的诊断价值。方法 选取2023年1月至2023年8月西安市第四医院收治的210例女性患者作为研究对象,均行经阴道超声及宫腔镜检查,以病理诊断结果为标准,分为CE组(n=119)和无CE的对照组(n=91),比较两组经阴道二维超声检查的子宫内膜厚度、回声均匀性、子宫内膜Applebaum分型情况,以及3D-PDA检查的子宫内膜血流参数,包括血管化指数(VI)、血流指数(FI)及血管-血流指数(VFI)。采用受试者工作特征(ROC)曲线分析子宫内膜厚度、回声均匀性、子宫内膜Applebaum分型、VI、FI、VFI对CE的诊断价值。结果 CE组子宫内膜厚度、Ⅱ型及Ⅲ型血流占比、VI、FI、VFI均小于对照组,内膜回声不均匀占比、Ⅰ型血流占比均多于对照组(t/χ^(2)值介于-2.831~89.249之间,P<0.05)。ROC曲线分析显示,子宫内膜厚度、内膜回声均匀性、VI、FI、VFI五项联合检测的诊断价值最高,AUC值为0.942,灵敏度87.90%,特异度为79.50%。结论 经阴道二维超声联合三维能量多普勒血管成像检查子宫内膜对CE的诊断价值较高,可作为一种无创性的临床诊断方法推广使用。 展开更多
关键词 慢性子宫内膜炎 三维能量多普勒血管成像 子宫内膜Applebaum分型
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降水微物理过程的C波段垂直指向雷达反演研究
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作者 黄梓恒 阮征 +2 位作者 何关兴 徐建春 苏德斌 《成都信息工程大学学报》 2024年第2期155-162,共8页
降水微物理过程是对空中雨滴的蒸发、碰并和凝结等演化过程的最直接描述。对降水过程中微物理特征的分析,有利于提高对云体的认识,为降水估计与数值模式参数化提供技术支撑。研究依托中国气象科学研究院灾害天气国家重点实验室在广东龙... 降水微物理过程是对空中雨滴的蒸发、碰并和凝结等演化过程的最直接描述。对降水过程中微物理特征的分析,有利于提高对云体的认识,为降水估计与数值模式参数化提供技术支撑。研究依托中国气象科学研究院灾害天气国家重点实验室在广东龙门建立的超级观测站,基于C波段调频连续波雷达高时空分辨率的多普勒功率谱数据。分析了2020年6月6-9日(前汛期),受西南季风影响,形成的一次持续时间长、累积雨量大、降水分布不均的降水过程中的几种典型对流单体的空中微物理特征。 展开更多
关键词 降水微物理 多普勒功率谱 西南季风 C波段调频连续波雷达
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