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101.
In a 2 year period seven patients who presented with stridor, without respiratory compromise, and three patients without obstructive symptoms were prospectively selected, and underwent MRI. In eight patients with a vascular ring and a pulmonary sling, MRI delineated the vascular abnormality and normal great vessels were found in two patients. Conclusion MRI successfully delineates the great vessels and demonstrates the presence of a vascular ring and pulmonary sling. Received: 15 May 1996 / Accepted: 17 January 1997  相似文献   
102.
纤维喉镜与核磁共振(MRI)在喉癌诊断中的应用   总被引:1,自引:0,他引:1  
将25例喉癌的术前纤维喉镜检查和喉部MRI与手术、病理进行比较,结果提示:纤维喉镜是喉癌诊断的最基本和最重要手段,能对T1、T2声门癌作出准确分期;MRI对显示粘膜面肿瘤虽然并不重要,但能准确判断肿瘤对会厌前隙、声门旁隙、喉软骨及喉外的侵犯;两者作用互补,对喉癌的诊断、术前分期及手术方法的选择具有重要意义。  相似文献   
103.
实验性脑脓肿影像学改变的病理基础研究   总被引:16,自引:0,他引:16  
目的:明确不同时期动物脑脓肿的影像学特征及其相应的病理学改变。方法:制备脑脓肿狗动物模型14只,采用CT、MRI检查结合多项病理学观测进行动态分析。结果:脑炎期MRI对炎症坏死区及水肿范围的显示较CT扫描更为清晰准确。包膜形成期:CT上脑脓肿包膜强化是炎症区血脑屏障破坏和新生血管形成所致;MRIT2加权成像上包膜的低信号“暗带”与包膜上的巨噬细胞堆积有关,延迟扫描和MRI均能有效地区分脑脓肿的急性脑炎期和包膜形成期,但MRI更加准确、迅速。结论:脑脓肿的MRI特征与其临床分期及病理学变化的相关性较好,能更加准确、简便、迅速地区别脓肿的脑炎期和包膜形成期,可作为临床诊治脑脓肿的有力参考。  相似文献   
104.
目的评价MRI在喉癌术前T分期中的价值。方法对59例喉癌的MRI资料进行回顾性分期,并与纤维喉镜及手术病理对照。结果MRI对各期喉癌分期的准确性分别是:T1:95%(20/21),T2:88%(15/17),T3:85%(11/13)T4:100%(8/8)。纤维喉镜分期的准确性是:T1:91%(19/21),T2:88%(15/17),T3:47%(8/13),T4:13%(1/8)。结论MRI能准确判断会厌前间隙(PES)、喉旁间隙(PGS)浸润及软骨破坏,因而可显著提高喉癌术前分期的准确性,对临床治疗方案选择具有重要意义。  相似文献   
105.
Subject: To study the role of MRI in the illustration of metastatic lymphatic pathways and clinical N-staging of nasopharyngeal carcinoma (NPC). Methods: Eighty NPC patients were examined with MRI before radiotherapy from Mar. 1994 to Jun. 1996. MRI were performed using T1 weighted image (T,WI) and T2 weighted image (T2WI) in transverse, and using T1WI in sagittal and coronal sections. Results: 1. NPC chief metastatic lymphatic pathways are: primary foci → Rouviere’s node (RN), or retrostyloid space nodes (RSN) secondarily → deep cervical nodes; 2. The superior border of neck fields should be moved upward to the level of external acoustic meatus; 3. The authors suggested that in N-staging for NPC, No and N1 be divided into Noa and N1b, and N1a and N1b. Conclusion: MRI is very useful in clinical N-staging of NPC, especially for the reflection of the influance of RN and/or RSN tumefaction on N-staging.  相似文献   
106.
We present a 70-year-old woman with pre-B acute lymphoblastic leukemia in whom serial imaging studies showed the development of multiple vertebral collapse, and communicating superior and inferior Schmorl’s nodes creating a longitudinal channel (”tunneling” Schmorl’s nodes) through the anterior aspect of T12 to L3 vertebral bodies of her osteoporotic thoracolumbar spine. This was observed after achieving complete remission of the disease and during maintenance therapy. The finding is felt to be secondary to iatrogenic exacerbation of osteoporosis. Received: 26 May 2000 Revision requested: 23 June 2000 Revision received: 10 July 2000 Accepted: 13 July 2000  相似文献   
107.
High-resolution magnetic resonance and volume rendering of the labyrinth   总被引:4,自引:0,他引:4  
Our aim was to verify the feasibility of volume rendering (VR) of high-resolution magnetic resonance (HR-MR) data sets of the labyrinth. We retrospectively reviewed the HR-MR data sets of 16 consecutive patients with no MR evidence of labyrinthine pathology. High-resolution MR data sets were obtained by means of a 3D T2-weighted FSE sequence with the use of a 3-in. circular surface coil for signal reception, and processed with a high-end workstation. Two reviewers performed separately VR of the labyrinth by selecting the signal intensity interval for attribution of opacity and transparency. Concerning the time taken for definition of the volume of interest, the two observers needed, respectively, 28.9 and 33.1 min (SD ± 8.7–9.5 min), whereas the time taken for VR was respectively, 26 and 33.2 min (SD ± 8.8–8.9 min). Concerning the selection of the signal intensity interval, the two observers had, respectively, 86.4 and 88.7 mean lower threshold (SD ± 34.5–33.5), 488.9 and 495.4 mean upper threshold (SD ± 56.3–53.8). In our experience, we have found VR of HR-MR to offer a reliable and reproducible technique for producing 3D representations of the labyrinth. The VR algorithms use all data within the imaging volume and optimize the dynamic range ascribed to the object being visualized. Received: 9 October 1998; Revised: 14 January 1999; Accepted: 30 June 1999  相似文献   
108.
目的了解马根维显(Gd-DTPA)动态增强核磁共振(MRI)评估肾积水术后疗效的应用价值。方法单侧肾积水患者11例,年龄7~42岁,平均19.5岁,均为男性;左侧肾积水9例,右侧2例;病因经静脉尿路造影(intravenousurography,IVU)和B超确诊,10例为先天性肾盂输尿管连接部狭窄(pelvicureterjunctionobstruction,PUJO),1例为输尿管中段慢性炎症所致不完全性梗阻;10例PUJO实施狭窄部成形术,另1例施行输尿管狭窄段切除并输尿管端端吻合术。应用Gd-DTPA作为对比剂,分别在术前1个月和术后3个月实施动态增强MRI检查,选取肾实质、肾盂和集合系统的类圆形区域作为兴趣区(regionofinteresting,ROI),计算不同时间点不同兴趣区的信号强度(signalintensity,SI)和相对信号强度(relativeSI,RSI),绘制T-SI曲线,对术前术后肾脏的形态和功能状态进行评估和比较。结果积水肾脏术前肾实质与术后综合评价无显著性差异(P>0.05),肾盂和集合系统排泄对比剂明显减慢,各ROI和SI以及持续时间与术后肾脏相比均有明显的差异(P<0.05)。结论动态增强MRI作为一种简单、安全无创的技术、联合评估肾形态和功能,对于评价肾积水手术疗效具有重要的临床价值。  相似文献   
109.
Muscle anomalies around the wrist, in particular the palmaris longus muscle, may cause effort-related median nerve compression. A search of the medical records at our university hospital between 1994 and 1999 revealed four patients with an effort-related median nerve compression due to a reversed palmaris longus muscle. Magnetic resonance imaging was used in the patient work-up and showed an anomalous muscle in each case that had been missed initially. All four patients were free of pain after simple excision of the anomalous muscle. Awareness of muscle anomalies at the wrist on MR imaging is essential in evaluating patients with nerve compressions at the wrist. The purpose of this article is to heighten this awareness in radiologists. Received: 23 June 1999; Revised: 30 September 1999; Accepted: 24 December 1999  相似文献   
110.
Intra-articular ganglion cysts of the cruciate ligaments   总被引:3,自引:0,他引:3  
Intra-articular ganglion cysts of the cruciate ligaments are associated with non-specific clinical signs and symptoms. Familiarity with the MR appearances in particular is important to make an accurate diagnosis, exclude associated abnormalities, and avoid misdiagnosis. Received: 6 August 1999; Revised: 23 November 1999; Accepted: 23 November 1999  相似文献   
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