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71.
目的研究Stargardt病(Stargardts disease,STGD)的眼底表现和眼底荧光血管造影(fundus fluorescein angiography,FFA)的特征.方法对27例54眼STGD患者进行视力、眼底及FFA检查.结果STGD患者的视力在0.02~0.10者46眼,占85.2%.眼底检查黄斑部均有横径为1.5~3.0 PD大小、呈青灰色并有金箔样反光的横椭圆形萎缩灶,其中15例30眼伴有眼底黄色斑点,占55.6%.FFA检查黄斑部病变为透见荧光,其中8例16眼呈"牛眼"状;22例44眼呈暗脉络膜背景,占81.5%.结论FFA检查在STGD的诊断中极为重要,在病程的不同阶段可有不同FFA表现.  相似文献   
72.
家兔急性周围型肺栓塞影像模型的制备   总被引:4,自引:0,他引:4  
目的探讨用可吸收性明胶海绵制作家兔急性肺栓塞(PE)影像模型的可行性。方法20只实验组家兔随机分成5组,采用明胶海绵栓子经股静脉插管制成急性PE的动物模型。栓塞后行肺动脉造影检查,栓塞后2h、24h、3d、7d、14d(A、B、C、D、E组)分批处死家兔,解剖肺动脉并观察栓塞区肺组织病理变化。对照组2只注入生理盐水,分别于第7天,14天处死。结果20只实验组家兔1只麻醉意外死亡,19只制备模型后成活,模型制备成功率95%。肺动脉造影显示46支叶及段肺动脉栓塞。肺动脉解剖共发现栓子65个,栓塞动脉50支。A组肺体积肿胀,色深红,镜下观察见肺组织充血。B组、C组、D组、E组中15只家兔肺表面呈苍白色、暗红色、黑色或苍白色区内见黑色坏死区,另外1只仅见肺体积肿大,肺颜色无变化,E组1只第3天左侧发生气胸,肺萎缩;光镜下观察肺组织水肿、淤血、出血、坏死,炎性细胞浸润,肺泡含气减少,肺泡支架结构破坏,E组2例栓塞区见肺组织机化,栓子周围有血小板血栓和/或混合血栓形成。对照组2只家兔肺部仅见少量炎性细胞浸润。结论用明胶海绵作为栓塞物制备家兔急性肺栓塞模型,其方法简便、成功率高,为肺栓塞影像学研究提供了一种较好的实验模型。  相似文献   
73.
目的探讨髂静脉多层螺旋CT成像的临床应用价值。方法50例患者行髂静脉多层螺旋CT血管造影,对比剂注射方案为经患侧足背浅静脉以2.5~3.0ml/s注射浓度为150mgI/ml的非离子型对比剂,延迟16~22s后开始扫描。利用多种重建方法进行重建。分析髂静脉的成像质量以及髂静脉疾病的影像特点。结果50例患者均成功完成CT血管造影。其中31例完全阻塞,9例管腔狭窄或见局部充盈缺损,10例完全通畅。图像质量优良率:优24%(12/50),良60%(30/50),差16%(8/50),总体优良率84%(42/50)。结论多层螺旋CT髂静脉成像对诊断静脉疾病有一定的临床价值。  相似文献   
74.
数字减影子宫输卵管造影术   总被引:3,自引:0,他引:3  
目的:介绍和评价数字减影与自动高压注射器联合应用于子宫输卵管造影(HSG)。方法:自行设计造影用硅胶管使之能与自动高压注射器相联接,用40%泛影葡胺和数字减影方法作造影;随机抽取常规透视点片碘油造影片44份,数字减影泛影葡胺造影片50份进行对照分析。结果:两组比较:清晰度宫腔无显著性差异(P>0.05),输卵管有显著性差异(P<0.05);输卵管通畅率、血管或(和)淋巴管回流率有显著性差异(P<0.05)。盆腔涂布无显著性差异(P>0.05)。结论:采用数字减影与高压注射器行子宫输卵管造影能提高造影质量。  相似文献   
75.
Homozygous familial hypercholesterolemia (HFH) is a very rare autosomal dominant disease characterized by accelerated severe atherosclerosis. We examined 18 patients from 9 families with HFH. The age range was 6-30 years (mean = 16 years). Male to female ratio was equal. All patients had huge, multiple tuberous xanthomas on the skin and tendons. Mean +/- standard deviation of plasma cholesterol, triglycerides, low-density lipoproteins (LDL), and high-density lipoproteins (HDL) cholesterol levels were 608 +/- 89, 122 +/- 39, 550 +/- 88, and 26 +/- 8 mg/dl, respectively. Five patients (28%) had angina pectoris, two sustained a myocardial infarction, and one died at the age of 15 years. Two-dimensional echocardiography demonstrated supravalvular aortic stenosis in 3 of the 13 patients (23%). Coronary arteriography performed in 11 patients demonstrated significant obstruction in 6 patients, 2 each with single-, double-, and triple-vessel disease. Left main stenosis was present in 3 patients (27%). Supravalvular aortic narrowing was demonstrated in 6 patients (54%) and was associated with a gradient in 2 (25 and 35 mmHg, respectively). Segmental contraction abnormalities were detected in 2 of the 11 patients (18%). It is concluded that coronary artery disease is prevalent in patients with HFH and, based on the data presented, we recommend the performance of noninvasive technique, coronary arteriography and supravalvular aortography at an early age to detect and to follow the progression of the disease.  相似文献   
76.
Results of 203 patients who underwent first pass radionuclide angiography (FP) and quantitative equilibrium radionuclide ventriculography (qERNV) were stored in a data base system and evaluated statistically. Eighty eight of these patients also underwent exercise equilibrium radionuclide ventriculography (E-qERNV). In patients with coronary artery disease (CAD) without previous myocardial infarction (MI), evaluation of global and regional ejection fraction (gEF, rEF) at rest revealed a poor sensitivity of 64%, the specificity was about 71% (qERNV). FP at rest revealed similar values of sensitivity (69%) and specificity (83%). Additional assessment of stress induced changes of gEF, significantly (P<0.05) improved sensitivity of qERNV in CAD patients without a history of previous MI to 84% (specificity 86%). In patients with one previous MI, however, similar values of sensitivity were found (RFP: 87%, R-qERNV: 84%, E-qERNV: 93%). In patients with several MI's, sensitivity was above 90% at rest and during exercise (R-FP: 96%, R-qERNV: 93%, E-qERNV: 100%).  相似文献   
77.
OBJECTIVE: The aortic connector system was used to minimize cerebrovascular complications when performing the proximal anastomosis of vein grafts during coronary artery bypass grafting (CABG). The goal of this study was to investigate the intermediate outcomes of patients undergoing CABG with the aortic connector system. METHODS: The aortic connector was used on nine patients undergoing CABG between November 2002 and July 2003. Intermediate outcomes of the patients were examined, and the results of coronary angiography, which were performed before patient discharge and at least 6 months after discharge, were evaluated. RESULTS: There were no operative deaths or cerebrovascular accidents. One patient died 9 months after discharge, one patient had angina, and the remaining seven patients were asymptomatic. When evaluating the results of angiography performed before patient discharge, two of the 21 distal vein graft anastomoses were occluded (patency rate, 90.5%), but there was no stenosis or occlusion at the proximal anastomoses sites that were performed using the aortic connector. When evaluating the results of the second angiography performed after patient discharge, four of the eight proximal anastomoses were patent, one was completely occluded, two had 90% stenosis and one had 75% stenosis. Further, four of the 18 distal anastomoses were occluded (patency rate, 77.8%). There was no significant difference in graft flow or device size when comparing patients with patent vein grafts and those with stenotic or occluded vein grafts. CONCLUSION: Intermediate outcomes of vein grafting using the aortic connector were suboptimal. Long-term outcome data are forthcoming.  相似文献   
78.
16层螺旋CT冠状动脉造影伪影分析   总被引:4,自引:0,他引:4  
目的:探讨16层螺旋CT冠状动脉造影伪影表现和成因,提高冠状动脉CT血管造影质量和诊断准确性。材料和方法:回顾性分析400例16层螺旋CT冠状动脉造影中失败及假狭窄诊断的38例图像,以DSA冠状动脉造影为金标准,分析上述病例中的伪影及假狭窄的CT表现。结果:伪影分为呼吸伪影、心律不齐伪影、冠状动脉搏动伪影、上腔静脉高浓度造影剂产生假斑块伪影、冠状动脉重度钙化产生的伪影,上述各种伪影均具有独特的影像特征。结论:准确分析CT冠状动脉成像伪影的影像表现及成因,对提高CT成像质量,减少诊断失误有很大的临床意义。  相似文献   
79.
三维CT脑血管造影在脑动脉瘤诊断中注意点   总被引:15,自引:2,他引:13  
目的探讨三维CT脑血管造影(3D-CTA)在诊断脑动脉瘤时的注意事项。方法回顾总结3D-CTA检查的106例蛛网膜下腔出血(SAH)病例,其中14例初次3D-CTA显示动脉瘤不清或发现颅内非动脉瘤样血管异常者,对其进行DSA脑血管造影检查。结果初次3D-CTA检查正确诊断脑动脉瘤92例,其中16例为多发脑动脉瘤,共检出115个。余14例因诊断不明确进而实施DSA脑血管造影检查,其中确诊动脉瘤合并烟雾病2例、严重脑血管痉挛致动脉瘤显示不清2例、脑动静脉畸形1例(此5例与3D-CTA所见一致);在3D-CTA扫查范围外发现脑动脉瘤2例。对上述阳性诊断的99例进行手术,并得到证实。另7例在3D-CTA和DSA检查未发现引起SAH的原因病灶,给予保守治疗。结论在脑动脉瘤诊断中,3D-CTA具有较好的精确性。在判断动脉瘤与颅骨位置关系、操作的便捷性和经济性等方面明显优于DSA。在应用3D-CTA对脑动脉瘤进行诊断时,有必要根据患者和设备的具体情况进行个性化设计,方能减少漏诊、误诊。  相似文献   
80.
To extend the signal longevity of magnetically excited spins in flowing fluids while in a state of global coherent free precession (GCFP), a refocusing radiofrequency (RF) pulse and bipolar gradient waveforms were combined with the GCFP sequence. The data demonstrate that RF refocusing in the presence of flowing blood is possible, but the improvement in signal amplitude depends on the static magnetic field homogeneity along the direction of motion and the displacement of the spins between the excitation and the RF refocusing pulse, as well as displacement during subsequent RF refocusing pulses. The least amount of phase dispersion and thus the longest lasting signal is obtained with the shortest echo spacing where only one line of data is recorded between two RF refocusing pulses. This approach was successfully used in a phantom and in vivo to image fast and slow blood flow. Depending on the experimental conditions, signal persistence is improved significantly compared to playing the same sequence without RF refocusing, but the improvement is limited by the product of blood flow velocity and the time between RF refocusing pulses.  相似文献   
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