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21.
纵隔类癌的CT表现(附6例报道)   总被引:4,自引:0,他引:4  
目的:分析纵隔类癌的CT表现,探讨CT诊断价值。方法:对1994年一2001年经4所医院病理证实的纵隔类癌6例进行临床、病理、CT对照分析。结果:①临床无特异性表现,极少出现类癌综合征;②CT表现为中上纵隔肿块,位于胸腺区或向其内生长,与心底部大血管及心包关系密切,并有沿血管间隙生长的特点,造影后有轻、中度强化,可发生胸内外转移;③CT表现与病理、预后密切相关。结论:纵隔类癌较罕见,可能来源于胸腺。CT发现以上特点可提示诊断,还可观察肿块大小、位置、范围、内部及与血管心包的关系,帮助确定手术方案及推测预后,但确诊需依靠病理。  相似文献   
22.
易自生  刘一平  杨帆 《放射学实践》2003,18(10):729-730
目的 :探讨节细胞神经瘤的CT诊断。方法 :回顾性分析 4例经手术病理证实的节细胞神经瘤的CT表现 ,并结合相关文献复习 ,讨论其影像特征。结果 :肿瘤位于脊柱旁或肾上腺区 ,直径均 >3 .5cm ,呈卵圆形 ,有完整包膜 ,呈较均匀低密度或欠均匀 ,多数病灶内可见点状高密度钙化。增强扫描呈轻度均匀或欠均匀强化。结论 :节细胞有一定的CT影像特点 ,CT能作出正确的定位及较准确的定性诊断  相似文献   
23.
目的:评价螺旋CT在诊断肺动脉栓塞中的作用。方法:16例肺动脉栓塞患者行螺旋CT肺动脉造影 (SCTA)检查,层厚3mm,扫描时间0.8s,对比剂注射速度3.5ml/s,总量100ml,扫描延迟时间15s。结果:16例 共644支,其中134支肺动脉及分支显示了栓塞,占20.8%。228支肺段肺动脉中,有56支显示肺动脉栓塞,占分 析肺动脉支的24.5%。204支亚段肺动脉中37支显示肺动脉栓塞,占分析肺动脉支15.4%。肺动脉栓塞的CT形 态:①直接征象为不同程度的肺动脉分支内充盈缺损。中心型充盈缺损17支,偏心型充盈缺损44支,附壁血栓型 34支,完全阻塞型39支。②间接征象胸膜下肺梗死灶,内乳动脉一侧增粗,肺纹理稀少,胸水,肺动脉高压。结论: 螺旋CT肺动脉造影是诊断肺动脉栓塞的快速、有效、无创伤的诊断方法。  相似文献   
24.
For selected indications, coronary computed tomographic (CT) angiography is an established clinical technology for evaluation in patients suspected of having or known to have coronary artery disease. In coronary CT angiography, image quality is highly dependent on heart rate, with heart rate reduction to less than 60 beats per minute being important for both image quality and radiation dose reduction, especially when single-source CT scanners are used. β-Blockers are the first-line option for short-term reduction of heart rate prior to coronary CT angiography. In recent years, multiple β-blocker administration protocols with oral and/or intravenous application have been proposed. This review article provides an overview of the indications, efficacy, and safety of β-blockade protocols prior to coronary CT angiography with respect to different scanner techniques. Moreover, implications for radiation exposure and left ventricular function analysis are discussed.  相似文献   
25.
Diagnosis of metastatic lesions to the stomach by salvage cytology   总被引:1,自引:0,他引:1  
Summary Secondary neoplasms of the stomach are rare and are often clinical and diagnostic problems. Three patients with bleeding volcano-like ulcers were diagnosed by combined endoscopic salvage cytology and surgical biopsy as having metastatic submucosal lesions from hematologic spread. The combination of endoscopic appearance, clinical findings, and tissue and cytologic examination can lead to the correct diagnosis. The results from these cases support the utility of this cytologic technique in combination with biopsy in this clinical setting.  相似文献   
26.
Intratemporal vascular tumors: detection with CT and MR imaging   总被引:1,自引:0,他引:1  
The diagnostic contributions of computed tomography (CT) and magnetic resonance (MR) imaging were compared in 12 patients with benign intratemporal vascular tumors (hemangioma or vascular malformation). The tumors included six in the internal acoustic canal and six in the geniculate ganglion region. Clinical and histologic correlations were made. Two of the six patients with tumors in the internal acoustic canal underwent CT, and both required gas cisternography to show the tumor. Five patients in that group underwent MR imaging, and all five studies showed the tumor. All six patients with geniculate ganglion tumors underwent CT. Results in one study were questionable, and five showed the tumor. Five patients in this group underwent MR imaging, but the MR findings were positive in only two cases. MR imaging should therefore be performed before CT in the evaluation of facial nerve dysfunction, as it demonstrated all tumors in the internal acoustic canal and some in the geniculate ganglion region. If MR findings are negative, CT should then be performed to rule out a possible geniculate ganglion lesion.  相似文献   
27.

Background

Reliable indicators that can intraoperatively determine the absence of nodal metastasis are in great demand to avoid unnecessary lymphadenectomy. However, little has been reported about the intraoperative diagnostic performance of sentinel node (SN) biopsy.

Methods

Sentinel node biopsy by subserosal or submucosal injection of indocyanine green (ICG) was performed in 241 patients with American Joint Committee on Cancer tumor, node, metastasis staging system, 7th edition, clinical T1 (n = 190) and T2 (n = 51) gastric cancer by two experienced surgeons. All nodes that stained green (green node, GN), representing SNs, were excised before gastrectomy and were sliced into 2-mm sections for intraoperative histological examinations with hematoxylin and eosin staining. The sliced GNs were also examined simultaneously by imprint cytology.

Results

The GNs were detectable in 240 patients (3.8 ± 2.4 nodes per patient; range 1–17 nodes; median 3 nodes), and the success rate of detection was 99.6 % (240 of 241). Of 240 patients with a successful detection, 29 were found to have lymph node (LN) metastases; 16 were diagnosed with LN metastases in both GNs and non-GNs, 12 in GNs alone, and 1 in non-GNs alone. The false-negative rate based on the SN concept was 3.4 % (1 of 29). However, two patients with cT1 gastric cancer were diagnosed as intraoperative GN negative but were later confirmed as GN positive by histological examinations of paraffin sections. As an intraoperative diagnosis, the false-negative rate was 10.3 % (3 of 29).

Conclusions

Sentinel node biopsy using ICG could be performed intraoperatively within reasonable limits under certain conditions, such as multiplanes for detection, combination use of imprint cytology, and open surgery by experienced surgeons.  相似文献   
28.
目的采用心脏MR(CMR)前瞻性研究冠状动脉斑块对心肌缺血的预测价值。方法 52例行冠状动脉造影(CA)后评定为可疑冠心病(CAD)的病人进行了CMR和  相似文献   
29.
肾脏嗜酸细胞瘤的CT诊断   总被引:13,自引:0,他引:13  
分析肾嗜酸细胞瘤的CT表现及其病理基础,以提高对此瘤的认识。材料与方法:2例肾嗜酸细胞瘤经病理诊断,术前均行CT平扫及增强扫描。结果;2例为单发肿瘤,直径为4.8cm及5.0cm。  相似文献   
30.
目的寻求制作门静脉高压动物模型的最佳方法,并以此为基础从事肝硬化后门静脉血液动力学基础研究。方法以3组共15只兔为动物模型,分别以0.2%、0.4%、0.8%浓度的白芨粉为栓塞材料,开腹注入兔门静脉内,手术前后行门静脉测压、血管造影及病理学检查,最长观察时间阎周.结果以0.4%浓度白芨粉制作门静脉高压模型最佳,4周后肝脏体积缩小20%,门静脉压平均升高40%,病理呈典型坏死后肝硬化表现。结论以白芨粉为栓塞材料制作肝硬化门静脉高压动物模型方法简单、效果可靠已重复性好.以不同浓度的白芨栓塞剂来控制坏死后肝纤维化的程度是本试验的一大特点,本动物模型的建立对深入研究肝硬化门静脉高压的成因及治疗措施有着重要意义。  相似文献   
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