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101.
下颌骨髁状突骨折的CT诊断 总被引:12,自引:0,他引:12
通过对比下颌骨髁状突骨折患者的普通X线和CT检查结果,着重提出CT诊断下颌骨髁状突骨折的方法及重要意义。 相似文献
102.
低剂量胸部螺旋CT扫描的应用价值 总被引:6,自引:0,他引:6
在CT扫描的各项检查中 ,胸部CT检查的患者占了很大比例 ,为了减少患者的X线照射量 ,延长球管的使用寿命 ,同时还要保证影像质量以满足临床诊断的要求 ,我们尝试了采用低剂量胸部螺旋CT的扫描方法 ,对患有肺部疾病的患者和健康体检人员进行肺癌普查 ,取得了令人满意的结果。1 材料和方法1.1 资料 MaxconiMx80 0 0。我院 2 0 0 1 12 10~ 2 0 0 2 4 10 ,共检查胸部CT患者 3 46人 ,其中女 12 4人 ,男 2 2 2人 ,年龄 14~ 93岁。1.2 扫描方法 患者仰卧扫描床上 ,手臂抱头 ,先行胸部正位定位像 ,再选择低剂量扫描程序 ,… 相似文献
103.
CT影像学评分预测急性胰腺炎病情及转归的研究 总被引:2,自引:0,他引:2
目的 探讨CT影像学评分对急性胰腺炎病情和转归的预测价值。方法 回顾性分析入院后经CT检查的急性胰腺炎46例,按一定的规则对每例患进行CT影像学评分与分型,并与临床治疗中的有关资料进行对照。结果 46例患CT评分后获得:轻型24例,中型13例,重型9例。轻型患较重型住院日少、恢复顺利,中转手术及死亡率均以重型为高。结论 CT评分对急性胰腺炎病情及预后评估具有重要意义。 相似文献
104.
Granulocytic sarcoma is an uncommon extraskeletal tumor most frequently associated with leukemia. We present a case of bone
location with unusual pattern in a patient with no evidence of myeloproliferative disorder at presentation or follow-up. 相似文献
105.
106.
M. Bertolotto G. Cecchini C. Martinoli R. Perrone G. Garlaschi 《European radiology》1996,6(5):637-639
A case of primary non-Hodgkin's lymphoma (NHL) of the mandible with unusual radiographic presentation is reported. The panoramic radiography revealed diffuse widening of the right mandibular canal with ill-defined margins and absence of edge sclerosis. Computed tomography showed infiltration of the superior portion of the canal with involvement of the vestibular cortex of the bone and of the alveolar ridge.
Correspondence to: M. Bertolotto 相似文献
107.
Richard Tello Reginald F. Munden Stuart Hooton Kris Kandarpa Robert PugatchAuthor vitae 《Computerized medical imaging and graphics》1998,22(6):267-452
Introduction: Features of spiral CT (SCT) — fast scanning, dynamic injection of contrast allowing optimal vessel opacification, and supplemental multiplanar imaging — promises to provide increased accuracy in the diagnosis of acute and non acute thoracic vascular disease. Recent work demonstrating the cost effective triage of hemodynamically stable patients after blunt chest trauma for angiography based on dynamic CT findings has prompted an investigation into the accuracy of SCT in this clinical setting. Methods: A retrospective review of all patients seen in the emergency department over the period of one year for aortic, thoracic, or blunt chest trauma evaluation was performed (74 patients) and all SCT scans available were reviewed and data reformatted for optimal delineation of pathology using maximum intensity projection and multiplanar reformation. The accuracy and predictive positive and negative values of SCT were calculated with respect to angiography, surgical, and/or clinical follow up evaluation. Results: Twenty three (31%) patients went directly to angiography owing to mediastinal widening on chest film and hemodynamic instability, of which four were positive and required emergent surgery. Seven hemodynamically stable patients (9%) had noncontrast SCT owing to mediastinal widening on chest film, all of which had angiography with none having great vessel trauma. Fourty four hemodynamically stable patients (60%) had contrast enhanced SCT (ceSCT), of which five (11%) were abnormal and underwent angiography, four of these were positive for aortic damage, one for a subclavian artery laceration. Of the remaining 39 patients who had normal ceSCT; five had angiography, all of which were normal. Of the remaining 34 patients that had normal ceSCT none had adverse outcome on clinical follow-up, minimum of 12 months. Conclusion: The predictive positive value for aortic trauma of ceSCT in blunt trauma is 80%, with a predictive negative value of 100%, indicating that it is feasible for SCT to be a first line exam in blunt chest trauma in the future. 相似文献
108.
P. Mildenberger H. U. Kauczor Katja Ehrhard W. Schmiedt M. Thelen 《Der Radiologe》1997,37(11):883-890
Purpose: Prospective evaluation of the accuracy of CT angiography (CTA) with different postprocessing for extracranial carotid artery
in comparison with DSA.
Method: one hundred patients were studied with standarized CTA. For postprocessing, MPR, MIP, and 3D reconstruction based on segmentation
with upper and lower threshold were used. Intravascular density profiles were considered. All CTA studies were correlated
with intra-arterial angiography. The degree and classification of stenoses was determined using the guidelines established
by the NASCET collaborators.
Results: Measurement of stenosis was possible by MPR in 82.5 %, by MIP in 85 %, and 3D in 100 %. Correct classification was found
in 65.5 % for MPR, 66 % for MIP and 88.5 % for 3D. The sensitivity for severe stenoses was 74 % for MPR, 82 % for MIP, and
93 % for 3D. The specificity of these methods was 98 %, 96 %, and 97 %, respectively. All carotid occlusions were correctly
identified, no carotid artery was wrongly classified as occluded.
Conclusions: CT angiography allows reliable examinations in carotid artery stenoses and occlusions. 3D reconstruction based on threshold
segmentation is superior to MPR and MIP. In some circumstances, e.g., carotid occlusion, further investigation by invasive
procedures is not necessary.
相似文献
109.
110.
S. Takahashi K. Ishii K. Matsumoto S. Higano T. Ishibashi M. Suzuki K. Sakamoto 《Neuroradiology》1994,36(5):337-339
We reviewed 12 cases of infarcts in the territory of the anterior choroidal artery (AChA) on CT and/or MRI. In each case vascular occlusion in the region was verified angiographically. Although the extent of the lesion on CT/MR images was variable, all were located on the axial images within an arcuate zone between the striatium anterolaterally and the thalamus posteromedially. The distribution of the lesions on mutiplanar MRI conformed well to the territory of the AChA demonstrated microangiographically. The variability of the extent of the infarcts may be explained by variations in the degree of occlusive changes in the AChA or the development of collateral circulation through anastomoses between the AChA and the posterior communicating and posterior cerebral arteries. The extent of the lesion appeared to be closely related to the degree of neurological deficit. 相似文献