Experience with the Amplatz retrievable vena caval filter. Work in progress

The Amplatz retrievable vena caval filter was designed in an attempt to decrease complications associated with the placement of Mobin-Uddin or Kimray-Greenfield filters. The design allows percutaneous retrieval, thus expanding application of the filter to situations requiring temporary prophylaxis against pulmonary embolism. Filters have been placed in 16 patients, nine (56%) for prophylactic purposes. All filters were easily inserted percutaneously. Complications occurred in three patients; these included complete thrombosis of the inferior vena cava below the filter, misplacement of one filter into the pericaval retroperitoneal tissue, and development of thrombus cranial to the filter. With the current introduction system, the possibility of filter misplacement has been essentially eliminated. No patient experienced symptoms suggestive of pulmonary embolism after filter insertion. One filter retrieval has been performed, with no complications.     

Pulsatile masses surrounding vascular prostheses: real-time US color flow imaging

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.     

Segmental dilatation of the small bowel: report of three cases and literature review

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.     

Dural infolding during C1-2 myelography

Inward buckling of the dura at C1-2 may occasionally occur with hyperextension of the neck and can result in a difficult or unsuccessful puncture when the posterior lateral C1-2 approach is used for cervical myelography. In this circumstance, placement of the head in a neutral or slightly flexed position may widen the posterior subarachnoid space and facilitate the needle puncture.     

Congenital abnormalities of the aortic arch: MR imaging

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.     

Anxiety in patients undergoing MR imaging

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.     

雷公藤春碱和雷公藤新碱的免疫抑制作用

雷公藤春碱(wilfortrine)和雷公藤新碱(euonine)ip 40及80 mg/kg对以溶血素反应为指标的体液免疫具有明显的抑制作。用雷公藤春碱ip 160mg/kg对GVHR为指标的细胞免疫也具有抑制作用。雷公藤新碱对DNCB所引起迟发超敏反应具有显著的抑制作用,并且能够降低小鼠碳廓清率和脾脏、胸腺的重量。