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91.
目的:探讨螺旋CT血管造影(Spiral CT angiography,SCTA)技术,以期提高SCTA造影的质量。材料与方法:采用Somatom Plus 4螺旋CT扫描系统对10例病人行腹部SCTA检查。扫描技术和造影剂参数按病变范围和性质而定,三维重建采用最大强度投影法(MIP)或表面阴影显示法(SSD)或弯曲平面重建法(CPR)。结果:SCTA检查技术能可靠地显示血管形态和病变,评价腹部肿瘤与邻近血管关系。结论:SCTA是无创伤性的血管成像术,在很大范围可替代创伤性的血管造影。 相似文献
92.
T. J. Vogl S. Steiner B. Schnell A. Gerbes C. McMahon C. Wilimzig J. Lissner 《European radiology》1992,2(4):310-316
Twenty-nine patients with diffuse liver disease were examined by ultrasound, CT and MRI. MRI was performed using T1- and T2-weighted spin-echo sequences as well as fast gradient-echo-sequences. The paramagnetic contrast agent Gd-DTPA was applied intravenously (0.1 mmol/kg). in patients with hepatitis, MRI could be used in guiding liver biopsies as inflammatory changes were clearly delineated. CT and ultrasound were superior to MRI in the detection of focal or diffuse fatty degeneration. On the other hand MRI was more helpful in differentiating fatty changes and neoplasm. In liver cirrhosis, fibrotic changes were most clearly demonstrated by MRI. In patients suffering from hemochromatosis MRI offers advantages over CT and ultrasound in the diagnosis and follow up due to the paramagnetic properties of iron, resulting in a reduction in signal intensity. In patients with Wilson's disease a characteristic pattern of parenchymal changes was seen. Administration of Gd- DTPA contributes additional information about perfusion conditions in the liver parenchyma, however this information was not of diagnostic relevance in the cases we studied.
Correspondence to: T.J. Vogl 相似文献
93.
A. Larsson Ch. Jensen M. Bilting S. Ekholm H. Stephensen C. Wikkelsö 《Acta neurochirurgica》1992,117(1-2):15-22
Summary Thirteen patients with normal pressure hydrocephalus were operated upon with an externally manoeuvrable shunt system (Sophy SU8) in order to investigate its influence on clinical outcome, intracranial pressure and cranial CT parameters. The opening pressure was set at high at surgery and lowered stepwise at intervals of three months to medium and low. The clinical condition, intracranial pressure and cranial CT parameters were examined at the end of the 3 months interval on each pressure level.The patients improved within the first 3 months inspite of an unchanged mean intracranial pressure and remained in a stable clinical condition during the rest of the study period. The intracranial pressure was significantly reduced at 9 months. The ventricular index, Evans index, temporal horn and third ventricle width were reduced 3 months post-operatively and did not change significantly during the rest of the study. The pre-operative third ventricle width was correlated to high psychometric test results after shunt surgery. Reduction in ventricular index, Evans index and third ventricle width after surgery correlated to improvement in psychometric scoring.The clinical improvement after shunt surgery for normal pressure hydrocephalus is seen within 3 months and is independent of the adjusted valve pressure. 相似文献
94.
95.
肺癌脑转移的CT研究 总被引:1,自引:0,他引:1
目的:研究分析肺癌脑转移瘤的CT特征和规律。材料与方法:回顾总结并分析经病理证实的74例肺癌脑转移病例,就其转移灶的CT特征和规律做出评价。结果:肺癌脑转移以顶、额叶为好发部位,转移灶主要表现为结节状均一强化和环状强化中心低密度,可单发或多发。瘤周水肿以腺癌和低分化癌较明显。环状强化中心低密度灶周水肿较结节均一强化灶周水肿明显。结论:CT增强扫描能清楚地显示转移灶的大小、部位、形态、边缘状况和密度变化,是肺癌脑转移的首选检查方法。 相似文献
96.
J. Menzel O. Schober P. Reimer W. Domschke 《European journal of nuclear medicine and molecular imaging》1997,24(6):635-641
In patients with liver cirrhosis a transjugularly placed intrahepatic portocaval shunt (TIPS) is a non-surgical portosystemic device which aims to reduce portal venons pressure. In comparison with Doppler sonography, we evaluated in 28 patients the diagnostic impact of liver perfusion scintigraphy (with technetium-99m diethylene triamine penta-acetic acid) in the assessment of changes in the hepatic blood flow after TIPS shunting. The arterial and portal contributions to hepatic flow were calculated from the areas under the biphasic timeactivity curve. In the course of TIPS shunting, patency is threatened by reocclusion. Angiography is the gold standard for TIPS shunt reassessment. However, there is a need for a less invasive diagnostic procedure, such as scintigraphy or Doppler sonography, for the early detection of shunt insufficiency. Scintigraphy demonstrated that prior to TIPS shunting the portal venons contribution to hepatic perfusion was reduced to 29.2%, this reduction being due to portal hypertension. After TIPS placement a significant increase in portal venous perfusion was observed (38.2%;P<0.02). TIPS shunt occlusion was identified in patients by a significant reduction in the scintigraphically measured portal venons contribution to hepatic blood flow. Hepatic perfusion scintigraphy appears to be a valuable method to determine the immediate effect of TIPS on hepatic blood flow. Post-TIPS follow-up studies of hepatic haemodynamics by liver perfusion scintigraphy appear able to contribute to the detection of TIPS shunt occlusion before the clinical consequences of this complication have become apparent. 相似文献
97.
98.
B. Bernardi C. Fonda E. Franzoni E. Marchiani E. Della Guistina R. A. Zimmerman 《Neuroradiology》1994,36(6):477-479
A case of infantile Krabbe's disease was first recognised as areas of relatively increased density on CT in the thalamus lateral geniculate body and dentate nucleus. These sites were subsequently shown on MRI to have a paramagnetic effect, being characterised by short T2 and T1. Subsequent examinations showed development of atrophy and high signal in white matter. 相似文献
99.
Results of surgical treatment in patients with arachnoid cysts 总被引:2,自引:0,他引:2
Summary A retrospective study of 35 patients operated upon for arachnoid cysts during the last 10 years was carried out. In 19 patients treated by craniotomy, membrane resection and drainage into the basal cisterns, clinical improvement could be noted in 13 cases. Correspondingly on the CT-controls the cysts were found to have disappeared in two cases and were reduced in size in seven patients.In 11 patients, however, who were initially treated by a shunting procedure, seven patients became free of symptoms. Postoperative CT-controls showed in three cases a significant reduction of the size of the cyst, which remained unchanged in two other cases.In five patients with the combination of a nonspace-occupying arachnoid cyst and subdural effusions, drainage of the latter only was sufficient to relieve the clinical symptoms.The prominent Endings were the high complication rate of the primary or secondary shunting procedures (48%), as well as the close correlation between the clinical outcome and the postoperative CT-controls. 相似文献
100.
A new radiolucent device for increased accuracy of CT-guided fine-needle punctures permits precise determination of the optimum
angle, depth, and position of the fine needle, which can be preset from the data supplied on the CT monitor. Puncture and
repeat scans for controlling the tip of the needle can be performed with the patient in a stationary position. The device
is designed as a belt that holds a needle holder sheath and a goniometric scale, both of which can be moved to varying positions
around the patient. 相似文献