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991.
Objective. To investigate the frequency and morphology of extraosseous extension in patients with Gaucher disease type I. Design and patients. MRI examinations of the lower extremities were analyzed in 70 patients with Gaucher disease type I. Additionally, the thoracic spine and the midface were investigated on MRI in two patients. Results. Four cases are presented in which patients with Gaucher disease type I and severe skeletal involvement developed destruction or protrusion of the cortex with extraosseous extension into soft tissues. In one patient, Gaucher cell deposits destroyed the cortex of the mandible and extended into the masseter muscle. In the second patient, multiple paravertebral masses with localized destruction of the cortex were apparent in the thoracic spine. In the third and fourth patient, cortical destruction with extraosseous tissue extending into soft tissues was seen in the lower limbs. Conclusions. Extraosseous extension is a rare manifestation of Gaucher bone disease. While an increased risk of cancer, especially hematopoietic in origin, is known in patients with Gaucher disease, these extraosseous benign manifestations that may mimic malignant processes should be considered in the differential diagnosis of extraosseous extension into soft tissues. A narrow neck of tissue was apparent in all cases connecting bone and extraosseous extensions. Received: 19 July 1999 Revision requested: 8 September 1999 Revision received: 7 October 1999 Accepted: 14 October 1999  相似文献   
992.
Objective. To analyse and compare all papers published to date (August 2000) that quantify the effectiveness, defined as the impact of clinician’s diagnosis or management plans, or patient outcome, of MRI of the shoulder. Design. A computerised search of Index Medicus with a broad search strategy relating to shoulder MRI was performed. Manual assessment of all papers listed was undertaken with classification of each paper depending on whether it addressed questions of (1) technical performance, (2) diagnostic performance or (3) outcome. Results. Four of 265 qualifying papers addressed aspects of effectiveness and these were reviewed. The impact on the clinician’s diagnosis varied widely between papers: the primary diagnosis was altered in 23% to 68% of cases, and the management plans were subsequently changed in 15% to 61% of cases. Only one paper addressed the impact on patient health. Conclusions. The effectiveness of MRI of the shoulder depends on the clinical skills of the referring clinician and prevalence of disease in the study population. This will have implications when the effectiveness of an imaging technique between different institutions is compared, and this in turn will influence any comparisons of cost-effectiveness. Received: 22 October 1999 Revision requested: 31 January 2000 Revision received: 21 August 2000 Accepted: 24 August 2000  相似文献   
993.
Objective. In magnetic resonance (MR) imaging of the shoulder, oblique coronal images are used for evaluating the supraspinatus tendon (SST) of patients with suspected rotator cuff tear or impingement. This study aimed to compare orientation of the SST long axis with planes perpendicular to the glenohumeral joint (GHJ). Design and patients. The axial scans of 100 consecutive patients referred for MR imaging or MR arthrography of the shoulder were reviewed. Using the electronic cursors of a computer workstation, the angle of the SST long axis was measured and compared with the angle obtained through the GHJ utilizing three different landmarks: perpendicular to the joint (GHJ-90), joint–humeral head center axis (GHJ-H) and joint–scapular body axis (GHJ-S). Results. Differences in angulation between axes of the SST and the three GHJ axes averaged only about 5° [range of means 4.5–5.3°, range of standard deviation (SD) 3.8–4.6°]. In the majority of shoulders, angular differences measured 4 or less for all SST/GHJ comparisons. Similarly, small angular differences in the three GHJ axes were found: 4.5° (SD 3.3°) for GHJ-90/GHJ-S, 5.0° (SD 4.0°) for GHJ-S/GHJ-H and 2.9° (SD 3.0°) for GHJ-90/GHJ-H. Correlation between the GHJ-90 and GHJ-H axes was particularly good, with differences of 4° or less in 84% of shoulders. The orientations of the GHJ axes and that of the SST long axis are comparable. Conclusion. The GHJ may potentially be used as a landmark for obtaining oblique coronal images of the SST. Received: 19 November 1999 Revision requested: 18 January 2000 Revision received: 27 March 2000 Accepted: 5 April 2000  相似文献   
994.
The aim of this study was to evaluate the sensitivity of the three-dimensional constructive interference of steady state (3D CISS) sequence (slice thickness 0.7 mm) and that of the T2-weighted fast spin echo (T2-weighted FSE) sequence (slice thickness 3 mm) for the visualization of all cranial nerves in their cisternal course. Twenty healthy volunteers were examined using the T2-weighted FSE and the 3D CISS sequences. Three observers evaluated independently the cranial nerves NI–NXII in their cisternal course. The rates for successful visualization of each nerve for 3D CISS (and for T2-weighted FSE in parentheses) were as follows: NI, NII, NV, NVII, NVIII 40 of 40 (40 of 40), NIII 40 of 40 (18 of 40), NIV 19 of 40 (3 of 40), NVI 39 of 40 (5 of 40), NIX, X, XI 40 of 40 (29 of 40), and NXII 40 of 40 (4 of 40). Most of the cranial nerves can be reliably assessed when using the 3D CISS and the T2-weighted FSE sequences. Increasing the spatial resolution when using the 3D CISS sequence increases the reliability of the identification of the cranial nerves NIII–NXII. Received: 29 September 1999; Revised: 2 February 2000; Accepted: 21 March 2000  相似文献   
995.
A case of recurrent abdominal wall abscess following percutaneous cholecystostomy (PC) is presented. Transperitoneal PC was performed in an 82-year-old female with calculous cholecystitis. Symptoms resolved and the catheter was removed 29 days later. The patient came back 5 months later with a superficial abscess that was drained and 8 months post PC with a fistula discharging clear fluid. Ultrasonography revealed the tract adjacent to an area of inflammation containing a calculus, whereas CT failed to depict the stone. Subsequent surgery confirmed US findings. To our knowledge, this is the first report of a dislodged bile stone following percutaneous cholecystostomy. Received: 27 August 1999; Revised: 7 December 1999; Accepted: 9 December 1999  相似文献   
996.
小动物PET及其在医药学研究中的应用   总被引:2,自引:1,他引:2  
小动物PET是一种无创伤性的分子影像学技术 ,是连接实验科学和临床科学的桥梁 ,在医药学研究中具有独特的价值。该文简要介绍小动物PET显像的优点与挑战、基本原理及小动物PET扫描仪的发展 ,并探讨小动物PET在医药学研究中潜在的应用价值  相似文献   
997.
目的:探讨影像组学方法在术前预测直肠非黏液性腺癌淋巴结转移中的价值。方法:回顾性分析91例手术病理切片证实为直肠非黏液性腺癌患者的影像学资料,其中61例为训练样本,30例为验证样本。基于全瘤体积,从每个原发病灶术前高分辨T2加权成像(T2-weighted imaging,T2WI)图像中提取影像组学特征1 301个。基于训练样本,利用最小绝对收缩和选择算子(the least absolute shrinkage and selection operator,LASSO)逻辑回归方法筛选关键特征并构建影像组学分类器。采用受试者工作特征(receiver operating characteristic,ROC)曲线评价影像组学分类器的辨别效能,并将其与形态学标准进行比较。在验证样本中验证影像组学分类器的价值。结果:由5个影像组学特征构建的分类器与淋巴结转移状态有关(P<0.001)。在训练样本和验证样本中,影像组学分类器诊断淋巴结转移的曲线下面积分别为0.874(95% CI:0.787~0.960)和0.878(95% CI:0.727~1.000),形态学标准诊断淋巴结转移的曲线下面积分别为0.619(95% CI:0.487~0.752)和0.556(95% CI:0.355~0.756)。无论是训练样本还是验证样本,影像组学分类器的诊断效能均高于形态学标准(均P<0.05)。结论:影像组学分类器可术前个体化预测直肠非黏液性腺癌淋巴结转移,而且其诊断效能高于形态学标准。  相似文献   
998.
目的:探讨应用体素内不相干运动扩散加权成像(intravoxel incoherent motion diffusion weighted imaging,IVIM-DWI)技术无创性评价早期慢性移植肾肾病(chronic allograft nephropathy,CAN)的可行性及临床应用价值。方法:收集符合本研究纳入标准的住院患者23例,其中经病理诊断为早期CAN的患者12例(CAN组),移植肾肾功能长期稳定的志愿者11例(对照组)。采用多b值DWI序列对移植肾进行磁共振扫描,利用IVIM2b_new软件获取移植肾的IVIM-DWI各定量参数伪彩图及测量肾实质的IVIM-DWI各定量参数值,包括真实扩散系数(D)、灌注相关扩散系数(D*)和灌注分数(f)。采用独立样本t检验对CAN组和对照组的IVIM各定量参数值进行比较,对差异具有统计学意义的指标进行ROC分析,并计算曲线下面积。结果:CAN组的定量参数D值低于对照组,差异具有统计学意义(P<0.05),两组间D*及f值的差异无统计学意义(P>0.05)。D值鉴别早期CAN的敏感度和特异度分别为58.3%和90.9%,曲线下面积为0.784。 结论:IVIM-DWI的定量参数D能在一定程度上无创性评价早期CAN。IVIM-DWI技术有望成为一种筛查早期CAN的简单有效的无创手段,以协助早期诊断与动态监测CAN。  相似文献   
999.
袁珊  谢席胜  冯胜刚  张红玉  郭志伟 《西部医学》2019,31(11):1730-1735
【摘要】目的 研究重复经颅磁刺激(rTMS)对尿毒症失眠患者的疗效及静息态功能磁共振成像(rs fMRI)下大脑自发神经活动低频振幅(ALFF)的变化。方法 选取2015年3月~2016年6月在南充市中心医院血液净化中心进行维持性血液透析的尿毒症失眠患者31例,分为rTMS治疗组(n=21)与空白对照组(n=10)。rTMS治疗组接受rTMS治疗,在治疗前后采用匹兹堡睡眠质量指数量表(PSQI)、阿森斯失眠量表(AIS)进行评分及rs fMRI图像采集。空白对照组不接受rTMS治疗,不采集rs fMRI图像,其余与rTMS治疗组相同。对比分析rTMS治疗组治疗前后睡眠量表评分及低频振幅(ALFF)的差异。结果 rTMS组治疗15d后,与治疗前及空白对照组入组15d后相比,尿毒症失眠患者睡眠情况明显改善。rTMS组治疗前后ALFF值比较,差异有统计学意义(P<005),其中双侧眶额叶、双侧杏仁核、左侧海马、左侧前扣带回的ALFF值增高,双侧脑岛的ALFF值降低。结论 低频可rTMS通过影响大脑相关脑区神经活动强弱来治疗尿毒症患者的失眠,改善睡眠结构。  相似文献   
1000.
周乐  李乔  刘兴会 《西部医学》2019,31(5):814-817
【摘要】随着磁共振技术的发展,用于成人颅脑的磁共振功能性序列,也可用于评价胎儿脑发育和脑功能,MRI在胎儿中枢神经系统的产前诊断中具有很高的价值。大量临床观察发现生长受限胎儿更易并发远期神经系统损伤及神经功能异常,采用胎儿功能核磁共振成像技术,可以发现T1WI和T2WI上看不到的神经系统变化。弥散加权成像(DWI)、弥散张量成像(DTI)、磁共振波谱(MRS)和血氧水平依赖(BOLD)MRI等磁共振新技术的应用,将进一步剖析胎儿脑发育的具体细节,同时对异常胎儿颅脑发育的诊断也会更加精确,从而对高危胎儿产前诊断及干预、妊娠结果提供重要的参考信息。胎儿MRI对早期、无创、联合定量检测胎儿生长受限具有很好的发展前景,但仍需进一步研究,使其更好更准确的服务于临床,本文对多功能MRI技术在胎儿生长受限的应用作一综述。  相似文献   
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