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11.
Mycotic aneurysms of the abdominal aorta are potentially fatal but uncommon. We report the MRI and MRA features of an abdominal aortic mycotic aneurysm in a patient who presented with nonspecific low back pain. By delineating the saccular nature of the aneurysm and identifying the coexistence of vertebral enhancement, MRI was crucial for the final diagnosis. A potential pitfall of contrast-enhanced MRA is also demonstrated.  相似文献   
12.
Summary In three consecutive cases of giant left sided paraclinoid aneurysms we employed an endovascular retrograde suction decompression technique in combination with intra-operative angiography. A double-lumen balloon catheter was placed in the left internal carotid artery by the transfemoral route. After balloon inflation and placement of a temporary clip distal to the aneurysm blood was aspirated and the aneurysm collapsed. Thus further dissection of the aneurysm could easily be achieved and clips could be placed. Afterwards real-time digital subtraction angiography was performed. Intra-operative angiography led to clip repositioning in all cases either due to a clip induced stenosis of the parent vessel, or because of incomplete aneurysm obliteration. Afterwards successful clipping could be confirmed in all cases. Outcome was excellent in one case, good in the other. The third case, extremely complicated by an accompanying craniopharyngioma, showed a satisfactory outcome, but presented new neurological deficits.  相似文献   
13.
The state of “nodding off” which the psychoanalyst may experience during therapy is a phenomenon that requires further investigation into its nature, causes, and effects. Even if it occurs only sporadically and is a physiological necessity, it nevertheless has a certain effect and can present certain advantages. This introduction of resistance in the form of sleep can sometimes provide an opportunity in the development of sensorimotor functions for the patient to verbalize his experience, and in any case this phenomenon should not be taken lightly. Recourse to current knowledge regarding sleep can improve our understanding of this phenomenon, and we should be prepared to take the risk of examining psychoanalysis on the basis of a non-analytical approach, i.e. primarily psychobiological and cognitive. This also permits a link to be made between the psychoanalyst’s therapeutic activity and the contextual phenomena which influence cerebral activity and its level of vigilance which is expressed by specific types of verbalization. The pertinence of this risk-taking should also be examined, and a distinction made between physiologically necessary somnolence and other causes. It appears that in the present context, the induction of a state of somnolence is caused by the narcissistic characteristics of a transferential relation that is in the process of development; that is to say, the “positive aspects’’ of narcissism, which are an integral part of psychic growth. However, we should also bear in mind that these narcissistic characteristics can also be expressed in the form of resistance.  相似文献   
14.
目的:分析血脂代谢异常与冠状动脉狭窄程度的关系.方法:对366例因胸痛而就诊的患者行选择性冠状动脉造影,按冠状动脉狭窄程度分为正常对照组、单支病变组、双支病变组、多支病变组.同时观察患者血脂各成分,并对各组指标进行统计学分析.结果:总胆固醇(TC)、甘油三脂(TG)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C),在各组之间存在差异,尤其多支病变组与正常组之间差异显著(P<0.01).TC、TG、LDL-C随冠状动脉病变加重而增加,HDL-C随冠状动脉病变加重而减少,LDL-C与冠状动脉狭窄程度呈正相关,HDL-C与冠状动脉狭窄程度呈负相关.结论:血脂代谢紊乱与冠状动脉狭窄的发生发展有内在的联系,对于预测有无冠状动脉病变及其进展有一定临床意义.  相似文献   
15.
Magnetization prepared segmented acquisition requires a view order that maximizes signal contrast during the acquisition of the central portion of k-space. Steady state free precession (SSFP) acquisition further requires a view order that minimizes changes in phase-encoding gradients from one repetition to the next in order to minimize eddy current artifacts. In this article, optimal view ordering schemes satisfying these two requirements are formulated and applied to inversion prepared 3D SSFP contrast-enhanced MR angiography (MRA). Experiments on phantoms and pigs demonstrated improved background suppression and reduced image artifacts.  相似文献   
16.
Summary A patient with symptomatic bilateral aberrant cervical internal carotid arteries, demonstrated on CT and MRI, is described.  相似文献   
17.
We describe a patient with two separate vessels having different origins supplying the circumflex coronary artery distribution. This represents a previously undescribed coronary artery anomaly.  相似文献   
18.
Coronary angioplasty is unsuccessful in <3–5% of cases because the balloon catheter fails to follow a guidewire that has traversed a lesion. Between June 1986 and August 1987, 31 lesions were unable to be crossed with at least two standard angioplasty catheters. Finally, a 2.0-mm-diameter Hartzler LPS (ACS) was utilized and successfully crossed and dilated 16 out of 31 lesions (52%). In the remaining 15 lesions, the ProbeTM (USCI) 2.0 mm diameter × 1.5 cm long balloon wire was able to cross the lesions in 13 (82%) and successfully dilated 12. In one case, lesion rigidity prevented the balloon from expanding at 14 atm. A right coronary artery lesion was attempted in 11 cases, and a left anterior descending and circumflex artery lesion in two patients each. No complications were encountered. In seven out of 12 successful ProbeTM cases, a larger balloon catheter was used to further dilate the artery. This new balloon wire has increased our success rate in severe stenoses and in tortuous vessels with severe distal lesions, in which presently available angioplasty equipment has failed.  相似文献   
19.
The morphological base for the impaired function of the blood retinal barrier was studied in 50 eyes of 10 insulin dependent and 21 non-insulin dependent patients with various levels of diabetic retinopathy. The permeability of the blood retinal barrier (PBRB) was determined by vitreous fluorophotometry with correction for autofluorescence, lenstransmission and non-protein bound plasma fluorescein concentration. Morphological abnormalities of diabetic retinopathy assessed by fundus photography and fluorescein angiography were individually scored on a decimal scale and related to the PBRB by multiple regression analysis. The Pbrb was not correlated to morphological abnormalities of non-proliferative retinopathy [(1) microaneurysms, (2) hard exudates, (3) soft exudates, (4) intraretinal hemorrhages, (5) fluorescein leakage, and (6) capillary closure, p > 0.3]. The PBRB was correlated to morphological abnormalities of (pre)proliferative retinopathy [(1) intraretinal microvascular abnormalities (Sirma) and (2) new vessels (Sneo): pbrb = A – B.SIRMA – C.Sneo with PBRB in nm/sec, A = 1.5 ± 0.5, B = 0.9 ± 0.2 and C = 1.7 ± 0.4, R2 = 0.65, p < 0.0001]. It can be concluded that the increased blood retinal barrier permeability in diabetic patients is mainly due to (pre)proliferative abnormalities and not to non-proliferative abnormalities.  相似文献   
20.
The recommended angiographic projections for optimally demonstrating various cardiac structures vary, and do not always achieve their aim. To determine the most appropriate radiographic projections to optimally demonstrate cardiac structures, we reviewed the orientations of major cardiac structures and the associated great vessels, as demonstrated by axial MRI. Measurements were made from 187 MRI examinations of the heart. These measurements confirmed that the optimum angiographic projections for various cardiac structures are at variance with a number of the recommended views. Recommendations for the angiographic projections most likely to provide optimum display of various cardiac structures and associated great vessels in different patient populations are presented. © 1993 Wiiey-Liss, Inc.  相似文献   
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