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101.
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
102.
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
103.
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
104.
彩色多普勒超声监测肝移植术后门静脉并发症 总被引:2,自引:0,他引:2
目的 探讨彩色多普勒超声(CDI)监测肝移植术后门静脉并发症的应用价值。方法 对107例次原位肝移植患者于术前、术后应用CDI进行连续监测,监测指标包括门静脉主干内径、血流速度、血流量、血流频谱、侧支循环及腹水量等。结果 4例受者术后出现门静脉并发症:门静脉狭窄2例,门静脉狭窄并血栓形成1例,门静脉右支闭塞1例。2例门静脉主干血流量明显减少者接受经皮腔内血管成形术治疗后,门静脉高压缓解;而CDI提示门静脉血流量末见下降的2例患者,仅接受保守治疗,存活时间均超过1年。结论 彩色多普勒超声动态检查对肝移植术后门静脉并发症较为敏感,作为无创性检查手段可用于肝移植术后门静脉并发症的监测。 相似文献
105.
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
106.
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
107.
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
108.
109.
The human foot is a complex mechanical structure consisting of bones, ligaments and joints. They act together to provide a robust system capable of absorbing and dissipating the intermitted pressure that is subjected to its plantar surface during walking to prevent soft tissue breakdown. Current studies suggest that plantar foot pressure may lead to soft tissue breakdown (e.g. neuropathic ulceration) and hence research has so far concentrated on investigating the mechanical effects of plantar foot pressure on the foot’s integrity. This has been possible through the widely available pressure and force platforms as well as in-shoe pressure systems. However, to understand how plantar foot pressure causes soft tissue breakdown it is vital to investigate both the physiological–mechanical interactions between the skin and plantar foot pressure. This review suggests that with the current advances in technology, the physiological response of skin blood flow to mechanical plantar foot pressure should be investigated and correlated further, both during static and dynamic loading, by developing a new system capable of either measuring both variables simultaneously or by synchronising two systems in real time. 相似文献
110.
目的 :探讨肝硬化门脉高压病人门静脉和肝动脉彩色多谱勒血流参数变化的意义。方法 :肝硬化伴食道静脉曲张的病人 6 6例 ,正常人对照组 5 8例。测量门静脉血流速度 (PVV)和肝动脉阻力参数 (HA- PI) ,计算肝血管指数。结果 :在肝硬化门脉高压病人比对照组 PVV明显降低 (12± 2 .2 ) cm/ s;(15 .8± 2 .6 ) cm/ s,P<0 .0 0 1)和 HA- PI明显增高(1.3± 0 .15 ;0 .94± 0 .16 ,P<0 .0 0 1) ,肝血管指数明显减低 [(8.6± 2 .1) cm/ s;(16 .7± 4 .2 ) cm / s,P<0 .0 0 1) ]。彩色多谱勒血流参数 PVV、HA- PI、肝血管指数对肝硬化门脉高压的诊断的敏感性和特异性分别为 89%、84 %、83%、81%、95%、91%。结论 :肝血管指数对肝硬化门脉高压的诊断的敏感性和特异性更高。 相似文献