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91.
Residual Flow Signals Predict Complete Recanalization in Stroke Patients Treated With TPA 总被引:4,自引:0,他引:4
Lise A. Labiche MD Marc Malkoff MD Andrei V. Alexandrov MD 《Journal of neuroimaging》2003,13(1):28-33
BACKGROUND: Residual blood flow around thrombus prior to treatment predicts success of coronary thrombolysis. The authors aimed to correlate the presence of residual flow signals in the middle cerebral artery (MCA) with completeness of recanalization after intravenous tissue plasminogen activator (TPA). METHODS: The authors studied consecutive patients treated with intravenous TPA therapy who had a proximal MCA occlusion on pretreatment transcranial Doppler (TCD). Patients were continuously monitored for 2 hours after TPA bolus. Absent residual flow signals correspond to the thrombolysis in brain ischemia (TIBI) 0 grade, and the presence of residual flow signals was determined as TIBI 1-3 flow grades. Complete recanalization was defined as flow improvement to TIBI grades 4-5. RESULTS: Seventy-five patients with a proximal MCA occlusion had median pre-bolus NIHSS 16 (85% with > or = 10 points). TPA bolus was given at 141 +/- 56 minutes (median 120 minutes). Complete recanalization was observed in 25 (33%), partial in 23 (31%), and no early recanalization was seen in 27 (36%) patients within 2 hours after TPA bolus. Only 19% with absent residual flow signals (TIBI grade 0, n = 26) on pretreatment TCD had complete early recanalization. If pretreatment TCD showed the presence of any residual flow (TIBI 1-3, n = 49), 41% had complete recanalization within 2 hours of TPA bolus (P = .03). CONCLUSIONS: Patients with detectable residual flow signals before IV TPA bolus are twice as likely to have early complete recanalization. Those with no detectable residual flow signals have less than 20% chance for complete early recanalization with intravenous TPA and may be candidates for intra-arterial therapies. 相似文献
92.
93.
彩色多普勒超声对高度近视眼后巩膜改变相关因素的评价 总被引:2,自引:0,他引:2
目的:探讨高度近视眼后巩膜形态改变与眼轴长度、近视程度及血流动力学变化之间的关系。方法:应用ATL超9型APOOGE-800型彩色多普勒超声诊断仪,探头频率5.0~10.0MHz。对26例正常眼,36例轻中度近视眼,51例高度近视眼后巩膜进行观察。并对26例正常眼,17例轻中度近视眼,26例高度近视眼的眼动脉(OA)、视网膜中央动脉(CRA)、睫状后动脉(PCA)进行检测。结果:轻中度近视组、高度近视组的眼轴长度与近视程度呈正相关性。两者之间的直线回归方程Y=-3510.3 1668.1X,R=0.9432,P<0.0001。后巩膜形态改变与正常对照组比较差异有显著性意义(P<0.001)。高度近视眼组、轻中度近视组与正常对照组比较,OA血流参数差异无显著性意义(P>0.05),而高度近视组的CRA、PCA的收缩期(PSV)、舒张期(EDV)、平均血流速度(AV)均减低,CRA的阻力指数(RI)升高(P<0.05)。轻中度组与对照组比较差异无显著性意义(P>0.05)。结论:视网膜血管、睫状血管系统血供不足与后巩膜形态变化的类型、眼轴长度、近视的程度及血流动力学改变密切相关,是引起高度近视眼病理性眼底改变发生和发展的重要因素。 相似文献
94.
Dr. Jerry Nagler MD Charles K. McSherry MD Paul Miskovitz MD 《Digestive diseases and sciences》1994,39(11):2476-2479
Summary A case of asymptomatic metachronous metastatic unilateral renal cell adenocarcinoma to the gallbladder detected five years after resection of the primary renal neoplasm is reported here. The lesion was diagnosed by contrast enhancement of a gallbladder mass on abdominal computerized tomography scan and by color Doppler sonographic study of the gallbladder, both of which demonstrated the vascular supply to the intraluminal gallbladder mass. The biological behavior of renal cell adenocarcinoma is reviewed. Guidelines for the evaluation of intraluminal gallbladder masses are suggested. 相似文献
95.
C Joseph Muniz Arthur C Fleischer Edwin F Donnelly Murray J Mazer 《Journal of ultrasound in medicine》2002,21(2):129-133
OBJECTIVE: To assess the accuracy of three-dimensional color Doppler sonography and uterine artery arteriography in depicting changes in fibroid vascularity before and after embolization. METHODS: Preembolization and postembolization three-dimensional color Doppler sonography and selective uterine artery arteriography were retrospectively compared in 15 patients who underwent uterine artery embolization for treatment of symptomatic fibroids. Three-dimensional color Doppler sonography was performed by using a scanner with color power angiographic imaging capability. Vascularity was quantified by using an estimation of power-weighted pixel density as described by our group in previously published studies. Uterine artery arteriography was performed by using a standard selective microcatheter embolization technique. For purposes of comparison, fibroids were classified as either hypervascular or hypovascular relative to myometrial vascularity before and minutes to several hours after uterine artery embolization. Changes in fibroid vascularity (i.e., from hypervascular to hypovascular) as depicted by three-dimensional color Doppler sonography were compared with those shown on uterine artery arteriography and classified as being in agreement or disagreement. RESULTS: In 13 (87%) of 15 patients there was agreement; in 2 (13%) of 15 there was disagreement. In both cases of disagreement, three-dimensional color Doppler sonography showed collateral flow not depicted by uterine artery arteriography The mean reduction in quantitated vascularity after uterine artery embolization was 44% (range, 19%-78%). CONCLUSIONS: Three-dimensional color Doppler sonography accurately depicts fibroid vascularity and in some cases can reveal collateral flow not depicted by uterine artery arteriography. 相似文献
96.
缺血性脑卒中急性期TCD,EEG,BEAM,CT的对比研究 总被引:1,自引:0,他引:1
目的 :对缺血性脑卒中急性期TCD动态观察 ,并与EEG ,BEAM ,CT等进行对比研究 ,以探讨TCD对缺血性脑卒中早期诊断、病情判断、治疗指导的价值 .方法 :发病 2 4h内首次发病的单侧MCA供血区缺血性脑卒中患者 2 3例 ,于入院即刻进行神经功能缺损评分及床旁TCD检查 ,在第 2 ,4 ,7d进行复查 ,入院当天进行EEG ,BEAM及CT检查 .门诊健康体检者 30人为对照组 .结果 :入院当天TCD异常率高于EEG ,BEAM及CT .入院当天病侧MCAVm降低 ,病侧ACAVm升高 ,分别与自身健侧及对照组比较差异有显著性(P <0 0 1) .MCA流速不对称指数 (AI)与神经功能缺损评分成正相关 (P <0 0 1) ,与BEAM慢波相对功率值成正相关 (P <0 0 5 ) ,与α波相对功率值成负相关 (P <0 0 1) .动态观察病侧MCAVm逐渐恢复并出现流速增高 ,而病侧ACAVm随之下降 .结论 :在缺血性脑卒中急性期TCD异常率高于BEAM ,EEG及CT ,异常程度与病情严重程度相关 ,动态观察可发现血管再通情况 ,具有较高的早期诊断、病情判断及治疗指导价值 相似文献
97.
I. Mastorakou D. R. M. Lindsell M. Piepoli S. Adamopoulos J. G. G. Ledingham 《Abdominal imaging》1994,19(4):369-373
In order to establish the normal range of values of Pulsatility (PI) and Resistance (RI) Indices in the intrarenal vasculature, a study of 50 healthy volunteers (23 males, 27 females), divided into five groups of 10 according to age, was performed with Duplex Doppler ultrasound. Both kidneys were examined in all individuals and, in 12, indices were also compared between upper and lower poles of both kidneys. In addition, repeat examinations were performed in nine subjects on three different days, in order to assess the reproducibility of the method. No differences were found in the mean values of both indices between males and females, upper and lower poles, right and left kidneys. A statistically significant increase (p < 0.01, unpaired t-test) was demonstrated when the oldest age group (7th decade) was compared to the youngest age group (3rd decade). The method appeared remarkably reproducible for RI (4.2–7%), with wider variation in the PI (9.5–22.7%). 相似文献
98.
食管超声多普勒监测急性高容量血液稀释对血液动力学的影响 总被引:4,自引:1,他引:3
目的 应用经食管超声多普勒血液动力学监测仪 ,观察全麻下急性高容量血液稀释(HHD)的血液动力学和氧供 (DO2 )变化。方法 选择 1 5例ASAI~II级择期行非心脏手术患者。麻醉诱导插管后持续监测心输出量 (CO)、每搏量 (SV)、心脏指数 (CI)、血流峰速度 (PV)、血流加速度(Acc)和左室射血时间指数 (LVETi) ,每隔 5分钟输入MAP值后计算出系统血管阻力 (SVR)值。麻醉平稳和各项监测完成后 1 0min ,在 30min内输注 6 %羟乙基淀粉 (HES) 2 0ml/kg。记录 6 %HES输注前、输注 1 5和 30min时的各项监测数据 ,并抽取动脉血液样本行血气分析并计算DO2 。结果 与HHD前相比 ,血气各参数 (pH、PaO2 、PaCO2 、BE)均无明显差异 (P >0 0 5 ) ,而 6 %HES输注 1 5和30min血红蛋白 (Hb)含量、红细胞比积 (Hct)均明显下降 (P <0 0 5和P <0 0 1 )。 6 %HES输注 1 5和 30min时的CaO2 比HHD前明显下降 (P <0 0 5 ) ,而DO2 显著增加 (P <0 0 5 )。与HHD前测量值相比 ,6 %HES输注 1 5min ,CO、SV、CI、PV和Acc明显升高 ,SVR显著降低 (P <0 0 5 ) ;6 %HES输注 30min ,SV、PV和Acc进一步升高 (P <0 0 1 ) ,而CO、CI和SVR与 6 %HES输注 1 5min时无明显变化。MAP、HR和LVETi在HHD期间无明显变化。结论 术前输注 6 %HES 2 0ml 相似文献
99.
M.C. TEREK S. TAMSEL† S. AYGUL L. AKMAN S.V. IRER‡ I.M. ITIL & G. ALPER‡ 《International journal of gynecological cancer》2006,16(1):376-379
The aim of this study is to evaluate the changes in Doppler resistive index (RI) and plasma creatinine and magnesium concentrations after unilateral ureteral obstruction in a rabbit model. Fourteen adult female rabbits were used in this study. In seven rabbits, the left ureter was ligated with silk suture, and the control group was sham operated. Before surgery and on the second and seventh days after surgery, blood samples were obtained to measure plasma creatinine and magnesium concentrations. Doppler RIs of both kidneys were also measured before surgery and on the second and seventh days after the surgical procedure. With regard to magnesium levels, there was a significant within-subjects sessions difference [F(2, 20) = 15.21, P= 0.001] indicating a decrease through sessions. Magnesium concentrations decreased significantly at the postoperative second and seventh days compared to preoperative baseline levels (P= 0.003 and P= 0.001, respectively). Multifactorial analysis of variance was applied for each session separately with laterality, and groups as factors. The Doppler RI and the creatinine level did not show any significant differences or interactions for all sessions (P > 0.05). The decreasing plasma magnesium concentration after surgery may indicate ureteral injury; however, Doppler studies and creatinine levels may not be useful as well. 相似文献
100.