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61.
In a prospective study we compared duplex-ultrasound characteristics of symptomatic internal carotid artery (ICA) stenoses with cranial computerized tomographic (CCT) findings in 82 patients suffering from completed or transient middle cerebral artery symptoms. The aim was to assess the pathogenic role of ICA plaque morphology and the potential embolic risk of ICA plaques. The degree of carotid stenosis was estimated by spectral analysis of the pulsed Doppler signal. The CCT findings were classified as being either normal, lacunar lesions, hemodynamically induced low-perfusion infarctions, or territorial embolic infarctions. According to their ultrasonic features we characterized the ICA plaque surface as smooth or irregular and their structure as homogeneous or heterogeneous. Plaques with an irregular surface and heterogeneous echogenicity dominated significantly in CCT-territorial infarctions (p < 0.01), whereas hemodynamically induced low-perfusion infarctions showed no relationship with any plaque characteristic. High degree ICA stenoses (> 50>%) dominated in both territorial infarctions and low-perfusion infarctions, as compared to ipsilateral normal CCT or lacunes (p < 0.05). Normal CCT and lacunar infarctions were associated with homogeneous and smooth plaques (both p < 0.05). We conclude that > 50% ICA stenoses can cause both hemodynamically induced low-perfusion infarctions as well as thromboembolic territorial infarctions, whereas ulcerated and heterogeneous plaques constitute a high risk factor for arterio-arterial embolic stroke. Furthermore, carotid ultrasound may help to estimate the clinical significance of carotid lesions. 相似文献
62.
Onelio Geatti Brahm Shapiro Pier Giuseppe Orsolon Gianni Proto Ugo Paolo Guerra Francesco Antonucci Daniele Gasparini 《European journal of nuclear medicine and molecular imaging》1994,21(1):17-22
Technetium-99m methoxyisobutylisonitrile (MIBI), like thallium-201, has recently been introduced as a myocardial perfusion agent and is now also showing very promising results in parathyroid scintigrapy. The results of 201Tl/99mTc-pertechnetate and 99mTc-MIBI/99mTc-pertechnetate subtraction scintigraphy, ultrasonography and computed tomography are presented in a series of 43 patients operated on for hyperparathyroidism. All four imaging modalities were confirmed to be reliable, scintigraphy being the most accurate. Sensitivities ranged from 81% to 95%, that of 99mTc-MIBI being the highest. Moreover this tracer, which has more favourable physical and also biochemical properties, yielded images of superior quality. This allowed localization of the lesion by visual inspection only in as many as 86% of the patients with positive 99mTc-MIBI/99mTc-pertechnetate subtraction scintigraphy. We believe that the higher sensitivity, superior image quality and lower cost of 99mTc-MIBI imaging will make 99mTc-MIBI the new radiopharmaceutical of choice for parathyroid scintigraphy (when one takes into account the stability of labelling with large activities it is possible to perform three or four cardiac studies together with one parathyroid scintigraphic examination using one lyophililzed vial). 相似文献
63.
泡型肝包虫病的超声诊断再探讨-附100例分析 总被引:1,自引:1,他引:0
目的:探讨泡型肝包虫病的B超特征,提出分型依据。方法:综合分析100例经手术或穿刺病理证实的B超声像图表现,并结合部分经CT、MRI检查病例对比研究。结果:100例泡型肝包虫,B超主要表现为①肝内不规则强回声团块80例,其中团块内呈弥漫性粗颗粒状强回声类似"落雪状"改变25例,团块内合并坏死液化20例,团块内钙化25例,钙化和液化同时出现10例。②肝内呈结节状改变20例。结论:泡型肝包虫病表现有其特征性,团块内粗颗粒状强回声,不规则液化坏死,斑片状钙化,周边无低回声暗晕以及彩超团块内无血流信号是与肝癌等肿块鉴别的重要依据。 相似文献
64.
经内镜微探头超声检查对结直肠黏膜下肿瘤的诊断价值 总被引:5,自引:0,他引:5
目的 探讨经内镜微探头超声检查对结直肠黏膜中肿瘤的诊断价值。方法 应用微探头对结直肠黏膜下肿瘤进行肠镜下超声检查。结果 28例结直肠黏膜下肿瘤中,平滑肌瘤12例,脂肪瘤7例,直肠类癌3例,淋巴管瘤3例。恶性淋巴瘤1例,肠气囊肿症1例和直肠腔外黏液囊肿1例,其中1例较大的平滑肌瘤误诊为平滑肌肉瘤。结论 经内镜微探头超声检查可以明确结直肠黏膜下肿瘤的大小,肠壁起源和边界,对黏膜下肿瘤的诊断有较高的准确率,同时能与控外压迫性病变相鉴别,术前经内镜微探头超声检查可以为结直肠黏膜下肿瘤患选择合适的治疗方案提供指导。 相似文献
65.
冠状动脉超声显像研究川崎病冠状动脉瘤:十二年回顾分析 总被引:21,自引:0,他引:21
1984年~1996年间应用冠状动脉超声显像研究川崎病502例,检出冠状动脉瘤(CAA)70例(13.9%),冠状动脉内径>4mm(CA/AO>0.30),呈校形扩张,51例(72.8%)1年好转。14例巨大CAA(BCAA)内径>8mm(CA/AO>0.60),回缩困难,经2~5年稍好转。7例并发冠状动脉血栓,2例并发心肌梗塞,4例并发腋动脉瘤,10例以心肌断层显像99mTC-MIBI对照研究,显示心肌灌注异常。1例CAA患儿因急性心肌梗塞死亡。冠状动脉超声显像用于诊断和随访川崎病冠状动脉瘤具有方便、迅速、直观、定位准确的优点,值得临床推广使用。 相似文献
66.
目的探讨胎盘早期剥离(胎盘早剥)的产前诊断和处理。方法对我院近10年发生的13例胎盘早剥作回顾性分析。结果妊高征及慢性高血压病占本组病因的46.2%。本组围产儿死亡率为23.08%,孕产妇死亡率为0。子宫卒中发生率46.15%,产后出血30.77%,DIC 7.70%。阴道出血、腹痛、胎心异常或消失、血性羊水为主要临床表现。产前诊断率为46.15%,B超检出率为60%。结论胎盘早剥的诊断需结合患者临床表现、发病诱因、B超检查结果全面考虑,确诊后应尽快终止妊娠。 相似文献
67.
目的 :观察椎动脉型颈椎病的高频彩色多普勒表现和血流动力学变化。方法 :应用彩色多普勒超声诊断仪 (高频探头 ,频率 7~ 10MHz)检测 138例椎动脉型颈椎病患者 (颈椎病组 )的椎动脉 (VH)内径 (D)、血流速度 (V)和血流量 (Q)、阻力指数 (RI)和搏动指数 (PI) ,观察其形态结构、并与 10 0例 (对照组 )进行对照分析。结果 :颈椎病组VA的V(除平均血流速度外 )、D ,Q ,RI,PI与对照组比较差异有显著性 (P <0 0 1)。结论 :高频彩超显示的椎动脉形态和血流参数变化为临床评价椎动脉型颈椎病治疗效果提供了有价值的依据 相似文献
68.
为探讨急性缺氧对飞行人员胃液体排空功能的影响,在常压下吸入不同浓度氧(17%、16%、14%、12%、10.5%及9%)的低氧混合气体30min,采用B型超声波在实验前后分别测量了64名男性飞行员的胃液体排空功能。结果表明,吸入17%低氧混合气胃排空延迟,但经统计学处理无显著性差异(P>0.05),吸入16%以下的低氧混合气后胃排空延迟,经统计学处理有显著性差异(P<O.01),且随着缺氧程度加重,胃液体排空时间延长更加明显。提示当发生高空缺氧时,应考虑到缺氧对胃排空有抑制作用这一因素。 相似文献
69.
Key words intractable pain - celiac plexus neurolysis - ultrasonography 相似文献
70.
Chung JH Yang JH Song MJ Cho JY Lee YH Park SY Moon MJ Lim HJ Choi JS Kim JO Shin JS Ahn HK Han JY Kim MY Choi KH Ryu HM 《Journal of Korean medical science》2004,19(1):32-36
The aim of present study was to establish normative data for the distribution of nuchal translucency (NT) thickness in normal Korean fetuses. The data were collected from pregnant women with singleton pregnancies in whom fetal ultrasound was performed and the fetal NT thickness was measured between 11 and 14 weeks of gestation. Among them, a total of 2,577 fetuses with a known normal outcome were included in this study. The distribution of multiple of median (MoM) values of the NT thickness with crown-rump length (CRL) in 10-mm intervals and the 95th percentile of MoM were calculated with the linear regression method. The present study showed that NT measurements increase with increasing CRL and a false positive rate increases with increasing gestational age. Therefore, a fixed cut-off point through the first trimester was not appropriate and each NT measurement should be examined according to the gestational age. The present study offers normative data of the fetal NT thickness in a Korean population, which can be used as reference for screening chromosomal aberrations or other congenital abnormalities in the first trimester. 相似文献