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131.
A 36-year-old man was brought to the emergency department after being assaulted. A mandible series showed a nondisplaced fracture through the angle of the mandible extending through the left third molar tooth. Axial slices from a nonhelical computed tomographic (CT) examination of the head as well as a helical CT examination of the mandible failed to demonstrate the fracture. The fracture was well shown, however, on sagittal CT reformations. Although CT is generally regarded as more sensitive than plain radiography for the detection of fractures, fractures may be overlooked by CT if examination in only one plane is performed.  相似文献   
132.
国产4环/7层PET仪初试   总被引:1,自引:0,他引:1  
对我国1996年研制成功的4环/7层PET仪(轴向视野8cm)进行试用。先进行模型试验和动物实验,然后对1例正常志愿者和7例患者进行18F脱氧葡萄糖(FDG)PET显像。静脉注射18FFDG370MBq后约15小时显像,成人全身显像行11个床位采集,约15小时,心脑局部显像行2~3个床位采集,约半小时。直径1~3cm的阴模和阳模皆可显示。8例全身冠状和矢状断层影像清晰,正常志愿者(正常进食)可见脑和心肌显影,膀胱内放射性较多。2例恶性肿瘤患者的6处病变浓聚18FFDG。2例恶性肿瘤患者手术和化疗后无复发征,显像阴性。2例良性病变处未见18FFDG浓集。1例陈旧性心肌梗塞患者18FFDG心肌断层显像与99mTc甲氧基异丁基异腈心肌血流灌注显像匹配良好。正常心肌显影与否受葡萄糖负荷的影响。8例脑皮质横断影像良好,基底节和丘脑影像有时尚欠清晰。初试结果表明,该PET仪相当于至今尚在国外广泛使用的80年代中期4环/7层PET仪水平,但具有90年代PET仪全身整体冠状和矢状断层显像的功能,可用于全身肿瘤显像、心肌活性判断和功能性癫痫灶术前定位,但仪器操作性能和软件功能尚需进一步完善。  相似文献   
133.
134.
Orbital hydatid cyst is rare. We present a case with CT and MRI, emphasizing the superiority of the latter. Received: 19 August 1996 Accepted: 9 September 1996  相似文献   
135.
We assessed predictors of spontaneous early neurological recovery after acute ischemic stroke by means of multivariate analysis in a cohort of 1,473 consecutive patients treated at one academic center. At hospital discharge, spontaneous neurological improvement or good outcome was defined as grades 0-2 of the Rankin scale, and poor outcome (no improvement or in-hospital death) as grades 3-5. Spontaneous recovery of neurological deficit at the time of discharge from the hospital was observed in 16% of patients with cerebral infarction (n = 238). Dysarthria-clumsy hand syndrome improved in 44% of patients and was the only variable significantly associated with in-hospital functional recovery in three logistic regression models that in addition to lacunar syndromes, included demographic variables, cardiovascular risk factors, and clinical variables [odds ratio (OR) 2.56], neuroimaging findings (OR 2.48), and outcome data (OR 2.39), respectively. Clinical factors related to severity of infarction available at stroke onset have a predominant influence upon in-hospital outcome and may help clinicians to assess prognosis more accurately. Our work gives a contribution into prognostic factors after acute ischemic stroke. With regard to patterns of stroke, dysarthria-clumsy hand syndrome was a significant predictor of spontaneous in-hospital recovery in ischemic stroke patients.  相似文献   
136.
回顾性分析了22例少见部位的脑膜瘤,22例CT表现不典型及8例CT误诊脑膜瘤的CT表现,以确定脑膜瘤不典型表现与CT误诊的关系。结果显示脑膜瘤的CT误诊多数缘于经验不足与疏忽,少数为极不典型表现所致。若检查全面、阅片仔细.术前CT定性率可由90%提高至96.25%。  相似文献   
137.

Background  

This study compared the prognostic value of exercise single-photon emission computed tomographic (SPECT) thallium imaging with that of treadmill exercise score in medically treated patients with coronary artery disease (CAD)  相似文献   
138.
Background: It is often difficult to detect a local recurrence of soft-tissue sarcomas due to disturbance of the normal anatomy by previous surgery and radiotherapy. The aim of this study was to assess the value of positron emission tomography (PET) with [18F]fluoro-2-deoxy-d-glucose (FDG) for detecting local recurrences. Methods: In the period 1992–1995, 17 patients with proven or suspected local recurrence of soft-tissue sarcoma were examined using FDG-PET. Fifteen of these patients were ultimately proven to have a recurrence. Results: Recurrence was visualized in 14 patients (93%). Small tumors (maximum diameter 0.5 cm) were as easily visible as large lesions (maximum diameter 20 cm). In one patient the PET scan was positive, but the recurrence could not be proven histologically. Recurrence was proven 1 year later. A recurrent low-grade liposarcoma was not visualized. The two patients with benign lesions had a negative PET scan. The mean glucose metabolic rate was calculated to be 13.2 μmol/100 g/min (range 1.9–28.4). A correlation was found between the histological malignancy grade and the metabolic rate (p<0.05; Kruskal-Wallis). Conclusion: PET with FDG is a useful addition to the diagnostic armamentarium for detecting local recurrence of soft-tissue sarcomas and provides an indication of the malignancy grade of the recurrent lesion. Presented at the 47th Annual Meeting of The Society for Surgical Oncology, Houston, Texas, March 17–20, 1994.  相似文献   
139.
This article reviews a focused helical appendiceal computed tomographic technique and discusses an approach to appendiceal computed tomographic interpretation.  相似文献   
140.
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