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排序方式: 共有1198条查询结果,搜索用时 0 毫秒
71.
Pediatric patients with achondroplasia: CT evaluation of the craniocervical junction 总被引:2,自引:0,他引:2
Twenty-six patients (4 months to 6 years old) with achondroplasia complicated by sleep apnea and/or other neurologic manifestations underwent plain computed tomography (CT) of the craniocervical junction; six also underwent CT myelography. For objectification, multiplanar reconstruction was used to complement axial plane measurements by providing coronal and sagittal measurements; multiplanar reconstruction also improved perception of the longitudinal relationships between the brain stem and subarachnoid space. A narrow subarachnoid space was found in all 26 patients; marked cord compression was present in nine, six of whom underwent CT myelography. These six had marked focal obliteration of the subarachnoid space on both plain CT and CT myelography. Since the subarachnoid space immediately above and below the craniocervical junction is normally capacious, when marked constriction was present, no additional information could have been gained from CT myelography. Thus, plain CT was shown to be sufficient for surgical planning (suboccipital decompression) in nine patients with cord compression due to achondroplasia. 相似文献
72.
Mewissen MW; Erickson SJ; Foley WD; Lipchik EO; Olson DL; McCann KM; Schreiber ER 《Radiology》1989,173(1):155-157
Color Doppler flow imaging or compression ultrasound (US) was used to prospectively determine frequency of thrombosis at 54 venous insertion sites (47 in common femoral veins, seven in right internal jugular veins) after percutaneous placement of Greenfield filters for interruption of the inferior vena cava. Fifty-one filters were successfully placed in 51 patients with a dilator set or a balloon angioplasty catheter. Nine focal thrombi were detected in the common femoral vein (19%) and one in the right internal jugular vein (14%). Use of dilators induced eight thrombi (24%), compared with two (10%) from balloon catheters. The left common femoral vein had a high frequency of thrombosis, regardless of dilation technique (five of nine). Of nine patients with acute common femoral vein thrombosis, four became symptomatic within 10 days after the procedure. Patients may remain asymptomatic or have delayed symptoms; thus, US is valuable for determining patients at risk of thrombosis of the common femoral vein. 相似文献
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Digital imaging of the chest 总被引:4,自引:0,他引:4
Fraser RG; Sanders C; Barnes GT; MacMahon H; Giger ML; Doi K; Templeton AW; Cox GG; Dwyer SJ d; Merritt CR 《Radiology》1989,171(2):297-307
During the past several years, image acquisition in nuclear medicine, computed tomography, ultrasonography, subtraction angiography, and magnetic resonance has been by digitization. Despite these advances, research in the development of digital imaging in conventional radiography has lagged behind. Although studies with a variety of digital techniques have been carried out on several fronts, we still do not possess a method that has captured the imagination of the majority of radiologists and other physicians to a point where it could replace conventional screen-film imaging. This article reviews the current status and general principles of the technology, focusing on the four digital radiographic techniques that have shown the greatest promise - film digitization, an image intensifier - based system, photostimulable phosphor plates, and a scanned projection system. The physical aspects of each of the four systems and the clinical results that have been reported to date, as well as the advantages and disadvantages of each system, are presented. 相似文献
79.
Cystic fibrosis: current survival and population estimates to the year 2000. 总被引:26,自引:16,他引:10
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BACKGROUND: Survival from cystic fibrosis is increasing rapidly. Estimates of the extent of this improvement should allow health care facilities to be planned to deal with the expanding population of patients with cystic fibrosis. Estimates of life expectancy are also essential if accurate information on current prognosis is to be given to parents of an affected child, or to prospective parents deciding whether to proceed with a pregnancy where the fetus may be affected. METHODS: Survival trends in the national data on cystic fibrosis have been analysed to produce estimates of the likely size of the cystic fibrosis population over the next decade and to predict the life expectancy of children born with cystic fibrosis in the years up to 1990. RESULTS: In England and Wales the estimated number of patients with cystic fibrosis is at present about 5200, of whom 3300 (63%) are aged under 16 years. By the year 2000 the total population will increase to 6000, with 3400 (57%) aged under 16. Thus the number of children with cystic fibrosis will remain fairly constant over the next 10 years, whereas adult numbers will increase by about 36% (from 1901 to 2577). The median life expectancy of children with cystic fibrosis born in 1990 is estimated to be 40 years, double that of 20 years ago. CONCLUSION: This study suggests that health service provision for children will not need to change substantially over the next 10 years whereas services for adults will need to increase by about a third. Parents can be counselled that the median life expectancy of a newborn child with cystic fibrosis is currently likely to be of the order of 40 years. 相似文献
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