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71.
Problem: There is a lack of clear criteria for the use of MR and CT in the diagnosis of head and neck cancer – some of it is even contradictory. The results of this study should lead to the establishment of more clear criteria. Patients: 165 patients suffering from head and neck tumors were subjected to a total of 463 CT and 197 MRI examinations. Results: The CT and MRI staging corresponded in 67% and 60% of the oropharynx tumors, respectively, with the clinical findings. In the case of oral cavity tumors, the clinical TNM stages were identical with CT and MRI results in 50% and 43% of cases, respectively. In the case of lymphatic node staging, the frequency of error was slightly higher using MRI, at 27%, compared with the CT rate of 22%. In the evaluation of cervical lymphatic nodes, CT proved to be more sensitive attaining 78% compared to the MRI rate of 69%. Conclusion: The results provide clear indications as to the MRI and CT examinations. Primary preoperative screening and post-therapeutic aftercare should be assessed using CT, as should lymphatic node diagnosis in the neck area. In the case of special problems such as, for example, the relevant bone and periostium infiltration, MR should be considered as a supplementary examination at a second stage.   相似文献   
72.
肺部CT扫描小病灶易遗漏 ,扫描前对定位图像观察细致 ,定位准确 ,则可达到检出病灶的目的 ,现报告如下。1临床资料1997年8月至1998年1月10例肺部0.5~0.8cm小病灶 ,男7例 ,女3例 ,年龄17~83岁 ,平均年龄57岁。病人仰卧于检查床上 ,双手抱紧头部 ,臀部垫高15°~25° ,定位线对准锁骨连线中心 ,先扫描全肺像 ,再根据病变情况 ,设定扫描程序。我科采用美国GEsystec3000型全身CT机 ,取XY轴线 ,从小病灶上缘 ,以3mm层厚 ,3mm层距 ,扫到病灶下缘为止。其他肺野 ,可用10mm层厚 ,1…  相似文献   
73.
The rationale and methodology behind the Australian Quality Assurance Project is described. The Project aimed to develop guidelines for treatment content based on three sources of information: research findings, current practice and expert opinion. The issue of the gap between research and practice is discussed, as well as the role of dissemination in altering clinician behaviour.  相似文献   
74.
AIM: To determine current clinical practice in the radiological diagnosis of acute pulmonary embolism and assess the use of spiral volumetric computed tomography. METHOD: A survey of 327 acute hospitals including cardiothoracic and orthopaedic tertiary referral centres was undertaken to assess current utilization of lung scintigraphy, spiral computed tomography and pulmonary angiography in the investigation of suspected pulmonary embolism. Responses were received from 215/327 (66%) centres. RESULTS: Lung scintigraphy was provided by 208 hospitals (144 on-site and 64 off-site). Spiral CT services were provided by 111 (52%) hospitals (on- or off-site), 142 (66%) units had access to angiographic facilities. Sixty-three centres out of 215 (29%) offered both on-site lung scintigraphy and spiral CT while only 41/215 (19%) hospitals were able to undertake all three tests on-site. On average, 501 perfusion (Q) or ventilation-perfusion (V/Q) scintigrams were performed per hospital per year with 26 spiral CT studies and just 4.6 pulmonary angiograms. CONCLUSION: These data suggest that lung scintigraphy is frequently the only imaging test in patients other than chest radiography, despite the large number of indeterminate results reported in most series.  相似文献   
75.
Zusammenfassung Ziel dieses Beitrags ist die Vorstellung der Untersuchungsm?glichkeiten des Ober- und Unterkiefers mittels Magnetresonanztomographie (Dental-MRT) und ihre Anwendung bei der Diagnose zahnmedizinischer Erkrankungen. Sieben gesunde Probanden, 5 Patienten mit Pulpitis, 9 Patienten mit dentogenen Zysten, 5 Patienten nach Zahntransplantationen und 12 Patienten mit atrophem Unterkiefer wurden untersucht. Axiale T1- und T2-gewichtete Gradientenecho- und Spinecho-Sequenzen in 2D und 3D-Technik wurden durchgeführt. Nach der Untersuchung wurden zus?tzliche Panoramaschnitte und orhoradiale Rekonstruktionen des Ober- und Unterkiefers, unter Verwendung einer gebr?uchlichen Dental-Software, angefertigt. Der gesamte Ober- oder Unterkiefer, Z?hne, Pulpa und der Inhalt des Mandibularkanals k?nnen gut dargestellt werden. Patienten mit einer Entzündung der Zahnwurzel k?nnen ein deutliches Knochenmarks?dem in der Periapikalregion zeigen. Bei Patienten mit odontogenen Zysten ist die Beziehungen zu den umgebenden Kieferstrukturen gut darstellbar. Nach Kontrastmittelgabe zeigt sich ein Enhancement in der Zahnpulpa. Die Dental-MRT ist ein nützliches Verfahren zur anatomischen Darstellung des Kieferbereichs und zahnmedizinischer Erkrankungen.   相似文献   
76.
Fibroepithelial polyps are the most frequently observed mesenchymal tumors of the renal pelvis. We report on one case of fibroepithelial polyp of the renal pelvis with unusual CT findings of totally cystic structure with septations. Received: 27 July 1998; Revised: 6 January 1999; Accepted: 8 February 1999  相似文献   
77.
CT of blunt trauma of the pancreas in adults   总被引:18,自引:0,他引:18  
In order to describe the CT findings in pancreatic injury and to evaluate the sensitivity of this technique, we performed a retrospective study. During a 5-year period (1993–1997), eight patients (five males and three females; age range 10–47 years) were investigated with CT. Endoscopicretrograde cholangiopancreatography (ERCP) was obtained in two patients, pre- and intra-operatively, respectively. Among the standard laboratory tests obtained at admission, the value of serum amylase was reviewed. The imaging findings, especially those obtained with CT, were correlated with the surgical findings, when available (in seven of eight patients). At admission, diagnosis of pancreatic injury was missed at CT in three of eight patients (37.5 %); thus, the sensitivity of CT for pancreatic injury was 62.5 %. ERCP showed rupture of the pancreatic duct in the two cases in which it was performed. Serum amylase was elevated at admission in four of eight patients, resulting in a sensitivity of 50 %. After surgery, an enterocutaneous fistula developed in one case, and was managed conservatively. One patient died from brain injury. Proper implementation of the CT technique and accurate film reading is mandatory to establish the diagnosis of pancreatic contusion. No correlation between CT features and type of outcome of surgical management could be established. On retrospective review of the CT examinations, it appeared that two of the three false-negative results could have been avoided. Therefore, proper CT technique and accurate film reading are mandatory in establishing the diagnosis of pancreatic injury. Received: 10 June 1998; Revision received: 26 October 1998; Accepted: 30 October 1998  相似文献   
78.
Multiple hepatic angiolipomas: a case report and review of literature   总被引:1,自引:0,他引:1  
Follow-up of two hepatic angiolipomas in a patient without evidence of tuberous sclerosis is reported. Initially, the lesions presented as homogenously enhancing masses, which were nearly isodense to normal liver tissue on plain CT scans. Focal nodular hyperplasia was assumed. One year later, fat was detected in the growing tumors and percutaneous core biopsy revealed hepatic angiolipomas. Natural history of these rare lesions is unknown, and this is to the best of our knowledge the first observation of fatty metamorphosis in such a benign, mesenchymal hepatic neoplasm. Received: 8 October 1997; Revision received: 19 March 1998; Accepted: 11 May 1998  相似文献   
79.
非瓣膜性心房纤颤与老年脑梗死   总被引:1,自引:0,他引:1  
目的 探讨非瓣膜性心房纤颤(NVAF)对老年缺血性脑卒中临床表现、预后的影响。方法 将58 例合并NVAF的老年急性缺血性脑卒中患者(AF组)与302 例不合并AF患者(NAF组)进行临床分析。结果 发现NVAF组有以下特点:(1)病情重,进展快,死亡率较高;(2)神经系统损害较严重;(3)腔隙性脑梗死发生率低;(4)颈内动脉闭塞常见;(5)预后差。结论 NVAF是引起老年缺血性脑卒中的危险因素,而且是影响其预后的重要因素。  相似文献   
80.
目的探讨原发性脑室出血的临床表现、脑CT征象及其与治疗的关系;方法回顾性分析28例经CT证实原发性脑室出血病人的临床表现及CT征象;结果多有头痛、呕吐等脑膜刺激征表现,无脑局灶受损体征,脑CT均示原发脑室出血;结论原发性脑室出血的诊断依靠脑CT,Ⅰ型脑室出血宜行侧脑室外引流术,预后较差,Ⅱ、Ⅵ型可行腰穿脑脊液置换术.预后较好。  相似文献   
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