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Mitchell DG; Merton D; Needleman L; Kurtz AB; Goldberg BB; Levy D; Rifkin MD; Pennell RG; Vilaro M; Baltarowich O 《Radiology》1988,167(2):303-306
Color Doppler imaging (CDI) can demonstrate the relative direction and velocity of blood flow in color, superimposed on a conventional gray-scale ultrasound image that depicts stationary tissue. Twenty-five infants were studied with portable CDI in the coronal, sagittal, and axial planes. Bilateral antegrade flow was noted in the anterior, middle, and posterior cerebral arteries in all patients. Multiplanar CDI can image flow in the circle of Willis and its tributaries and branches. 相似文献
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Klatskin tumors of the bile ducts: sonographic appearance 总被引:4,自引:0,他引:4
The authors present 3 cases of surgically proved Klatskin tumor diagnosed by ultrasound alone. Sonographic features of these tumors include (a) dilatation of the intrahepatic biliary ducts but not the extrahepatic duct, (b) non-union of the right and left hepatic ducts, and (c) small, solid masses at the hepatic hilus. Local spread to the liver may also be seen. If the pancreas appears normal and no primary tumor can be found, Klatskin tumor can be diagnosed with a high degree of accuracy. 相似文献
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DG Ranatunga MG Richardson DM Brooks 《Journal of Medical Imaging and Radiation Oncology》2007,51(2):182-185
Knotting of intravascular catheters is an uncommon but a well‐recognized occurrence. The Swan–Ganz catheter (SGC) is the one that knots most commonly. A case of a knotted SGC is described in a patient with a persistent left‐sided superior vena cava, and we propose that the presence of a left‐sided superior vena cava is a risk factor for knot formation not previously reported. We review the published work on the risk factors for knot formation and on the techniques used to remove knotted SGC. We describe a technique using a gooseneck snare and Omni Flush catheter (Angiodynamics, Queensbury, NY, USA) to loosen and untie a knotted SGC. 相似文献
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Rugby union injuries to the cervical spine and spinal cord 总被引:1,自引:0,他引:1
Injuries to the cervical spine are among the most serious injuries occurring as a result of participation in rugby. Outcomes of such injuries range from complete recovery to death, depending on the degree of spinal cord damage sustained. Much information has been gained regarding the mechanisms and frequency of such injuries, from case reports and case series studies. The most commonly reported mechanism of injury has been hyperflexion of the cervical spine, resulting in fracture dislocation of C4-C5 or C5-C6. Tracking both the trends of incidence of spinal injuries, and the effectiveness of injury prevention initiatives has proved difficult because of a lack of properly conducted epidemiological studies. Within the constraints of the research published to date, it appears that hookers and props have been at disproportionate risk of cervical spine injury, predominantly because of injuries sustained during scrummaging. While the scrum was the phase of play most commonly associated with spinal injuries throughout the 1980s in most rugby playing countries, there has been a trend through the 1990s of an increasing proportion of spinal injuries occurring in the tackle situation. The majority of injuries have occurred early in the season, when grounds tend to be harder, and players are lacking both practice and physical conditioning for the physical contact phases of the sport. A number of injury prevention measures have been launched, including changes to the laws of the game regarding scrummaging, and education programmes aimed at enforcing safe techniques and eliminating illegal play. Calls for case-registers and effective epidemiological studies have been made by researchers and physicians in most countries where rugby is widespread, but it appears to be only recently that definite steps have been made towards this goal. Well-designed epidemiological studies will be able to provide more accurate information about potential risk factors for injury such as age, grade, position, gender and ethnicity. Research into the long-term effects of participation in rugby on the integrity of the spinal column is warranted. 相似文献
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Careful study of the pathophysiology and epidemiology of sports-related spine injuries brings to light many common features. The incidence increases as the sport becomes increasingly violent and aggressive. Poor conditioning and lack of knowledge of the proper techniques of the sport put the athlete at significant risk for head and spine injury. Improper helmet fit and the use of the head as an offensive weapon also are common features of injury. Although recognition of these features has resulted in a dramatic reduction in catastrophic neurological injury, the athlete remains at risk for less severe head and spine injury, and concussion remains at epidemic proportions at high school, university, and professional levels. It is hoped that careful recognition of the signs of concussion and knowledge of return-to-play criteria will prevent catastrophic complications from minor head injuries, although the long-term effects of multiple concussions on cognition may be problematic. 相似文献
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