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141.
Percutaneous nephrostolithotomy, which can require a double puncture, is presently the method of choice in our institution for the removal of renal stones. Patients that underwent this procedure were evaluated to identify the possible reasons for the double puncture. Of 200 patients evaluated, 14 needed a second tract. The three variables that determined whether a second puncture was needed, in order of importance, were number and size of the stones, with second tracts needed in patients with multiple stones and staghorn calculi; anatomical variations of the renal collecting system itself, with bifid systems the most significant anatomic variation; and the dexterity of the radiologist in performing the puncture and the ability of the urologist to extract the stone. Second tracts were needed more frequently in patients who presented with stones in both the lower and middle poles of the collecting systems.  相似文献   
142.
Experience with the Amplatz retrievable vena caval filter. Work in progress   总被引:1,自引:0,他引:1  
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.  相似文献   
143.
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   
144.
Ratcliffe  J; Tait  J; Lisle  D; Leditschke  JF; Bell  J 《Radiology》1989,171(3):827-830
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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147.
Blood pulse wave velocity (PWV) is a known index of arterial rigidity and its measurement has proved its usefulness in the study of some cardiovascular pathologies. In this study we describe the design and implementation of a system for noninvasive PWV determination in the aorto-braqui-humero-radial (A-->h), aorto-ileo-femoro-pedial (A-->f) and aorto-carotid (A-->c) regions. This system was examined with 36 normotensives (NT) and 34 hypertensives (HT) patients with (LVH, n = 20) and without (WLVH, n = 14) left ventricular hypertrofy. The equipment consist of a personal computer with an analog to digital converter and hardware and software items adapted to take simultaneously the electrocardiogram (ECG), two photopletismographic pulses and one oscilometric pulse. The Q-pP interval (time between a Q ECG wave and distal blood pulse) and the distance to the register sites are taken into account to calculate the beginning of cardiac prexpulsive period (time zero of pulse trip) which allow the determination of the PWV (in meters/second) from the aortic root to the distal point of the via. PWV was significant higher (p < 0.001) in HT vs. NT (A-->h: 9.3 +/- 2.6 vs. 7.2 +/- 0.8, A-->c: 9.5 +/- 2.8 vs. 6.0 +/- 1.9 and A-->f: 9.5 +/- 1.8 vs. 7.2 +/- 0.9) in each evaluated arterial region. Same thing occurred in cases with LVH vs. WLVH (A-->h: 10.5 +/- 1.6 vs. 8.0 +/- 1.9, A-->c: 10.2 +/- 1.9 vs. 8.0 +/- 1.9 and A-->f: 10.5 +/- 2.0 vs. 8.6 +/- 1.2) (p < 0.025). This is consistent with the relationship more pressure [symbol: see text] more rigidity and with other reports. This method may have clinical application.  相似文献   
148.
Burt  TB; Seeger  JF; Carmody  RF; Yang  PJ 《Radiology》1986,158(2):546-547
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.  相似文献   
149.
Congenital abnormalities of the aortic arch: MR imaging   总被引:1,自引:0,他引:1  
Gomes  AS; Lois  JF; George  B; Alpan  G; Williams  RG 《Radiology》1987,165(3):691-695
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   
150.
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