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A prospective evaluation of color flow mapping and real-time ultrasound was performed to determine if pseudoaneurysms could be distinguished from other causes of masses surrounding vascular grafts of the lower extremities. Twelve palpable pulsatile masses were imaged. Diagnoses were confirmed at angiography (n = 11), computed tomography (n = 7), aspiration biopsy (n = 5), and operative intervention (n = 6). A swirling pattern of blood flow was seen in six of seven cases of pseudoaneurysm. Lack of flow signals was noted in four of the five collections representing hematoma (n = 2) or infection (n = 2). The seventh case was later shown to be an infected, thrombosed pseudoaneurysm. The single false-positive diagnosis was made early in the series when the flow signals detected were due to transmitted arterial pulsations. The authors conclude that color Doppler flow imaging is useful in the differential diagnosis of pulsatile masses associated with prosthetic grafts. Prosthetic graft pseudoaneurysms have a specific appearance of swirling blood flow arising from a wide neck and are distinguishable from traumatic or iatrogenic pseudoaneurysms of the native vascular tree. 相似文献
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Segmental dilatation of the small bowel is a rare congenital abnormality that occurs mainly in children and produces significant nonspecific symptoms. The authors reviewed 33 cases reported in the literature and present three new cases in which the lesion was demonstrated on radiographs obtained before laparotomy. These cases showed the spectrum of symptoms and characteristic radiologic features of this condition in both plain abdominal radiographs and barium studies. Plain radiographs of the abdomen may show an isolated loop of bowel containing an air-fluid level. The characteristic finding in barium studies of the small bowel is a localized dilatation of the small bowel lumen with afferent and efferent loops. In the absence of a complication or coexistent cause of obstruction, the transit time of contrast medium through the small bowel is not delayed. The radiologic examination is useful in diagnosis, and the condition is cured with surgery. 相似文献
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Congenital abnormalities of the aortic arch: MR imaging 总被引:1,自引:0,他引:1
Thirty-four patients, 1 month to 63 years old, with known or suspected congenital abnormalities of the aortic arch underwent magnetic resonance (MR) imaging. Sixteen patients were studied retrospectively, 18 prospectively. In all retrospective studies, the aortic arch abnormality was seen with MR imaging. In the prospective studies, MR imaging enabled diagnosis in 15 of 18 (83%) patients. Twenty-nine of 34 patients underwent two-dimensional echocardiography; nine were studied retrospectively, 20 prospectively. In the prospective studies, echocardiography enabled diagnosis in 13 of 20 (65%) patients. Although two-dimensional echocardiography has a high sensitivity in the detection of aortic arch abnormalities in the neonate, arch abnormalities in the neonate, its sensitivity is lower in older children, adults, and postoperative patients. The authors' experience shows that MR imaging is an important, noninvasive modality in the evaluation of older children, adults, and postoperative patients with congenital aortic arch abnormalities. 相似文献
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Anxiety in patients undergoing MR imaging 总被引:6,自引:0,他引:6
To determine and quantify the major sources of anxiety for patients undergoing magnetic resonance (MR) imaging and to suggest means by which to eliminate or diminish their negative effects, the authors studied anxiety in 46 subjects. Of these, 20 randomly selected subjects who successfully completed the examination participated in exit interviews. Six subjects who terminated the examination before completion also completed exit interviews. Pre-imaging and postimaging questionnaires (state-trait anxiety inventory) were administered to measure anxiety in the 20 other subjects. Anxiety was associated with the constrictive dimensions of the magnet bore, examination duration, coil noise, and temperature within the bore. Preparation at the point of referral was consistently absent, incomplete, or misleading. Patients used identifiable strategies to cope with the examination: blinding, breathing relaxation techniques, visualization of pleasant images, and performance of mental exercises. 相似文献
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目的:观察蜂胶乔松素对脂多糖诱导人脐静脉内皮细胞的影响,探讨其对人脐静脉内皮细胞可能的保护作用。方法:实验于2006-03/10在泰山医学院生命科学研究所(省重点实验室)完成。①实验材料:取出生1h内新生儿脐带,患者知情同意。②实验分组及方法:培养人脐静脉内皮细胞,建立脂多糖损伤模型(以10mg/L的脂多糖培养液培养细胞12h),实验分为空白对照组(加等量D-Hank’s液)、脂多糖组(10mg/L)、乔松素组(加10mg/L脂多糖预孵育12h后,按50,100,200mg/L分别加入乔松素),各组设8个复孔,共同孵育24h。③实验评估:光镜下观察细胞形态,MTT法观察乔松素对人脐静脉内皮细胞活性的影响,ELISA方法检测培养上清中血管假血友病因子的含量,TUNEL检测细胞凋亡率。结果:①细胞形态:空白对照组细胞紧密贴壁,呈铺路石状生长。脂多糖组可见多数细胞呈圆形;乔松素组见上述细胞较脂多糖组明显减少。②乔松素对人脐静脉内皮细胞活性、凋亡及血管假血友病因子含量的影响:与对照组比较,脂多糖组能明显诱导人脐静脉内皮细胞的凋亡(P<0.01),不同浓度乔松素组可改善内皮细胞形态,组织活性明显升高(P<0.05),同时抑制内皮细胞血管假血友病因子的释放(P<0.05),使脂多糖诱导的人脐静脉内皮细胞凋亡细胞数明显减少(P<0.05)。结论:乔松素能增强人脐静脉内皮细胞活性,抑制脂多糖诱导人脐静脉内皮细胞的凋亡,从而发挥可能的内皮细胞保护功能。 相似文献
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