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991.
SUMMARY Exomphalos and vitellointestinal duct remnants are well-known entities. This report details the presentation of congenital fistulation of a Meckel's diverticulum to the surface of an exomphalos minor. 相似文献
992.
993.
Mycotic aneurysms in intravenous drug abusers: the utility of intravenous digital subtraction angiography 总被引:1,自引:0,他引:1
Two-hundred thirteen intravenous digital subtraction angiographic (DSA) examinations were performed on 195 intravenous drug abusers to rule out the possibility of a mycotic aneurysm in a groin, neck, or upper extremity infection. Twenty-three surgically proved cases of mycotic aneurysm were correctly identified with no false positive results. In addition, six cases of major venous occlusion were documented. We present the results of our experience and conclude that DSA is an effective and cost-efficient method of examining this high risk patient population. 相似文献
994.
Magnetic resonance imaging (MRI) of the breast was performed in 35 women using a prototype breast coil at 0.15 T. The distribution of fibroglandular and fatty tissues was demonstrated sufficiently well to permit correlation with the mammographic patterns of Wolfe, and it was possible to identify 1-cm cysts. The signal intensity of the cysts varied from low to high as repetition time (TR) and echo time (TE) using the spin echo technique (TR/TE) were prolonged from 250/30 to 1,000/120. In two women, fibroadenomas were seen as low-intensity, smoothly marginated lesions surrounded by fat. A range of in vivo observed T1 values is summarized for normal and pathologic tissues. It is concluded that MRI of the female breast, currently in the developmental phase, is feasible and further evaluation is indicated. 相似文献
995.
Leptomeningeal metastasis: MR imaging 总被引:3,自引:0,他引:3
Seven patients with central nervous system neoplasia and leptomeningeal metastases, proved either at initial diagnosis or on follow-up with contrast material-enhanced computed tomography (CT), were evaluated with magnetic resonance (MR) imaging. In two patients, diffuse sulcal enhancement on CT scans was inapparent on T1- or T2-weighted MR images. Likewise, in four patients diffuse cisternal enhancement on CT scans was not identifiable with MR. Nodular or focal cisternal masses were identified with both CT and MR imaging in three patients; in two, however, MR imaging provided less information. Ependymal and subependymal metastases identified with CT (two patients) were indistinguishable on MR images from periventricular abnormalities of radiation therapy and/or hydrocephalus. These findings suggest that leptomeningeal metastasis may be so subtle or inapparent as to be overlooked with MR imaging alone. Thus, CT and MR imaging should be considered complementary techniques for initial diagnosis and follow-up of tumors with a propensity for leptomeningeal metastasis. 相似文献
996.
Among 603 patients scheduled for a breast biopsy at the authors' institution in 1987, the biopsy was canceled on the day of the procedure in 53 (8.8%). All had been referred from other facilities. An analysis of the original mammograms and the additional imaging procedures performed is presented. The reasons for termination of the planned biopsies include (a) no mass present (n = 22), (b) aspiration of a mass (n = 13), (c) skin calcifications (n = 9), (d) random calcifications (n = 4), (e) skin artifacts (n = 3), and (f) other (n = 2). Practicing radiologists should adapt rigid criteria for biopsy recommendation and propose radiographic follow-up for low-suspicion abnormalities detected. 相似文献
997.
Colorectal carcinoma evaluation with CT: preoperative staging and detection of postoperative recurrence 总被引:31,自引:0,他引:31
CT was performed prior to surgery in 103 patients with colorectal carcinoma to assess its value in staging the tumor. Preoperative IBD scans had sensitivities and specificities of 72.7% and 98.9% in detection of liver metastases, 25.9% and 96% in detection of lymph node metastases, and 61.2% and 80.6% in detection of local extension. Compared with the Duke's classification, CT correctly staged only 47.5% of patients: 16.6% were upstaged, and 83.3% were downstaged. Recurrent tumors developed in 11 of 67 patients followed for more than 24 months. CT depicted recurrence in six patients scanned prior to 12 months. Routine scans obtained at 12 months depicted unsuspected tumor recurrence in three of four patients with proved recurrent disease (one patient with pulmonary metastases did not undergo CT). This study indicates that because of the poor accuracy of CT in preoperative local staging of colorectal carcinoma, it has virtually no useful clinical role in this regard. However, preoperative CT evaluation of the liver can be useful. Routine postoperative CT, combined with fine-needle aspiration biopsy, is useful for detection of recurrent tumor. 相似文献
998.
Adult respiratory distress syndrome in children 总被引:1,自引:0,他引:1
Clinical, radiological, and pathologic data for nine children with adult respiratory distress syndrome (ARDS) were reviewed. The children ranged in age from 7 months to 15 years (mean age, 7.4 yrs). Underlying diseases and precipitating events included sepsis, pneumonia, near drowning, aspiration pneumonia, central nervous system trauma, and malignancy. All patients had the rapid onset of diffuse bilateral lung opacification, required assisted ventilation for periods of 5-86 days (mean, 25.2 days), and received high levels of inspired oxygen for 2-41 days (mean, 12.7 days). Eight patients manifested air leak complications; these problems persisted until the patients died or were weaned from the respirator. Five of the nine patients died. Autopsy in three patients demonstrated alveolar duct fibrosis characteristic of the late proliferative phase of ARDS and consistent with oxygen toxicity. Two survivors demonstrated mild restrictive changes on follow-up pulmonary function tests and showed persistent linear densities on chest radiographs. 相似文献
999.
Flunarizine, a Calcium Entry Blocker in Migraine Prophylaxis 总被引:3,自引:0,他引:3
SYNOPSIS
To obtain a sample size sufficiently large to enable valid statistical analysis, patients with common or classical migraine treated in different centres with the calcium-entry blocker flunarizine, 10 mg daily, were pooled into 2 sets. In a first group of 202 patients, flunarizine was shown to reduce the frequency of attacks in 83%. Improvement was more marked when the duration of the disease was shorter and was more rapid when the pretreatment frequency of attacks was high. Somnolence and weight gain, sometimes labeled increased appetite, were the main adverse reactions but rarely caused withdrawal of the drug. Weight gain was significantly correlated with the global result and occurred more in patients with a low pre-treatment weight. In a second group of 125 patients, most of them being treated for a year, the effect of flunarizine was fully sustained at the 4-month level, i.e., at a median reduction in attacks by 51% to 60%. 相似文献
To obtain a sample size sufficiently large to enable valid statistical analysis, patients with common or classical migraine treated in different centres with the calcium-entry blocker flunarizine, 10 mg daily, were pooled into 2 sets. In a first group of 202 patients, flunarizine was shown to reduce the frequency of attacks in 83%. Improvement was more marked when the duration of the disease was shorter and was more rapid when the pretreatment frequency of attacks was high. Somnolence and weight gain, sometimes labeled increased appetite, were the main adverse reactions but rarely caused withdrawal of the drug. Weight gain was significantly correlated with the global result and occurred more in patients with a low pre-treatment weight. In a second group of 125 patients, most of them being treated for a year, the effect of flunarizine was fully sustained at the 4-month level, i.e., at a median reduction in attacks by 51% to 60%. 相似文献
1000.
A localization grid for use with magnetic resonance (MR)-guided biopsies was designed and evaluated. First, the signal intensities of various concentrations of Gd-DTPA in polyethylene tubes of different sizes and at various pulse sequences were evaluated. The optimal signal intensity on all pulse sequences was obtained with a concentration of 500 microM. A grid was then made with 5-mm-diameter polyethylene tubes filled with 500-microM Gd-DTPA. The grid has provided excellent localization for MR-guided biopsy and fluid aspiration. 相似文献