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71.

Background

The purpose of this analysis is to describe the differences in cardiac magnetic resonance characteristics between benign and malignant tumors, which would be helpful for surgical planning.

Methods

This was a prospective cohort study of 130 patients who underwent cardiac magnetic resonance imaging for evaluation of a suspected cardiac mass. After excluding thrombi and tumors without definitive diagnosis, 66 tumors were evaluated for morphologic features and tissue composition.

Results

Of the 66 patients, 39 (59.0%) had malignant tumors and 27 (41.0%) had benign tumors. Patients with malignant tumors were younger when compared with those with benign tumors (age 51 years [42.8-60.0] vs 65 years [60.0-71.0] median). Malignant tumors more often demonstrated tumor invasion (69% vs 0% P < .001) and were more often associated with pericardial effusion (41% vs 7.4% P = .004). Presence of first-pass perfusion (100% vs 33% P < .001) and late gadolinium enhancement (100% vs 59.2%, P < .001) were significantly higher in malignant tumors. In logistic regression modeling, tumor invasion (P < .001) and first-pass perfusion (P < .001) were independently associated with malignancy. Furthermore, using classification and regression tree analysis, we developed a decision tree algorithm to help differentiate benign from malignant tumors (diagnostic accuracy ~90%). The algorithm-weighted cost of misclassifying a malignant tumor as benign was twice that of classifying a benign tumor as malignant.

Conclusions

Our study demonstrates that cardiac magnetic resonance imaging is a useful noninvasive method for differentiating malignant from benign cardiac tumors. Tumor size, invasion, and first-pass perfusion were useful imaging characteristics in differentiating benign from malignant tumors.  相似文献   
72.
We herein report a case of Klebsiella pneumoniae (K. pneumoniae) spondylitis and bacteremia in a 90-year-old man with diabetes mellitus who had undergone sigmoidectomy and had a fecalith. Two months prior to admission, he had received antimicrobial treatment for 2 weeks for K. pneumoniae bacteremia whose entry was unclear and he was readmitted to our hospital owing to fever and stomachache. K. pneumoniae was isolated from two sets of blood cultures, and computed tomography and magnetic resonance imaging revealed inflammation and destruction of the 8th and 9th thoracic vertebra. The diagnosis was spondylodiscitis secondary to K. pneumoniae bacteremia. Although the entry point for K. pneumoniae was unclear, we suggest that inflammation of the mucosa around the fecalith might have caused the Enterobacteriaceae bacteremia.  相似文献   
73.
Recognition of <3 metastases in <2 organs, particularly in cancers with a known predisposition to oligometastatic disease (OMD) (colorectal, prostate, renal, sarcoma and lung), offers the opportunity to focally treat the lesions identified and confers a survival advantage. The reliability with which OMD is identified depends on the sensitivity of the imaging technique used for detection and may be predicted from phenotypic and genetic factors of the primary tumour, which determine metastatic risk. Whole-body or organ-specific imaging to identify oligometastases requires optimization to achieve maximal sensitivity. Metastatic lesions at multiple locations may require a variety of imaging modalities for best visualisation because the optimal image contrast is determined by tumour biology. Newer imaging techniques used for this purpose require validation. Additionally, rationalisation of imaging strategies is needed, particularly with regard to timing of imaging and follow-up studies. This article reviews the current evidence for the use of imaging for recognising OMD and proposes a risk-based roadmap for identifying patients with true OMD, or at risk of metastatic disease likely to be OM.  相似文献   
74.
75.
Purpose:It has been reported previously that intravenously administered gadolinium-based contrast agent (GBCA) leaks into the subarachnoid space around the cortical veins at 4 h after injection in all old people over 37 years, but not in younger people up to 37 years of age in 3D-real IR images. The purpose of this study was to investigate whether there was a strict threshold of 37 years of age for the leakage of the GBCA into the subarachnoid space.Methods:The subjects included 190 patients, that were scanned for 3D-real IR images at 4 hours after intravenous injection of GBCA as a diagnostic test for endolymphatic hydrops. The patient’s age ranged from 14 to 81 years. Two experienced neuroradiologists evaluated the images to determine whether the GBCA leakage around the cortical veins was positive or negative. Any discrepancies between the two observers were discussed and a consensus was obtained.A Mann–Whitney U test and receiver operating characteristic (ROC) curve analysis were used to compare the positive and the negative group and to set the age cut-off value for the prediction of GBCA leakage.Results:The GBCA leakage around the cortical veins was negative in 35 patients and positive in 155 patients. The average age was 33 ± 11 years in the negative group, and 55 ± 12 years in the positive group (P < 0.01). In the ROC analysis for the age and leakage of the GBCA, an area under the curve was 0.905 and the cut-off age was 37.317 years (sensitivity of 0.942 and specificity of 0.771).Conclusion:Intravenously administered GBCA leaks into the subarachnoid space around the cortical veins in most patients over 37 years of age. However, it should be noted that it can be found occasionally in patients under 37 years of age.  相似文献   
76.
The presented case reports on successful treatment with everolimus in a neonate with left ventricular giant rhabdomyoma. The authors used a different dosage regime compared to literature and documented rapid tumor regression by 3D echocardiography.  相似文献   
77.
Additive manufacturing is a rapidly emerging technology which is being successfully implemented in the various field of medicine as well as in orthopaedics, where it has applications in reducing cartilage defects and treatments of bones. The technology helps through systematic collection of information about the shape of the "defects" and precise fabrication of complex 3D constructs such as cartilage, heart valve, trachea, myocardial bone tissue and blood vessels. In this paper, a large number of the relevant research papers on the additive manufacturing and its application in medical specifically orthopaedics are identified through Scopus had been studied using Bibliometric analysis and application analysis is undertaken. The bibliometric analysis shows that there is an increasing trend in the research reports on additive manufacturing applications in the field of orthopaedics. Discussions are on using technological advancement like scanning techniques and various challenges of the orthopaedic being met by additive manufacturing technology. For patient-specific orthopaedic applications, these techniques incorporate clinical practice and use for effective planning. 3D printed models printed by this technology are accepted for orthopaedic surgery such as revision of lumbar discectomy, pelvic surgery and large scapular osteochondroma. The applications of additive manufacturing in orthopaedics will experience a rapid translation in future. An orthopaedic surgeon can convert need/idea into a reality by using computer-aided design (CAD) software, analysis software to facilitate the manufacturing. Thus, AM provides a comprehensive opportunity to manufacture orthopaedic implantable medical devices.  相似文献   
78.
目的阐明CDFI对评价胎儿宫内状况的可行性。方法200例经普通B超检查的胎儿,按测量各项常规指标的数值分为正常组100例和异常组100例,再分析经CDFI检查,所测定的指标包括胎儿大脑中动脉、肾动脉、胎盘床动脉、脐动脉血流搏动指数(PI)、阻力指数(RI)及脐动脉的收缩与舒张期峰值速率之比(S/D)。对其结果做详细记录,并进行统计学分析。结果正常组100例,经CDFI检查亦正常;胎儿出生时体重在2500g以上,新生儿发育正常。另100例异常组经CDFI检查各项指标中,54例正常,46例异常;胎儿出生时体重均小于2500g,其中54例新生儿虽体重较正常儿偏小,但发育正常;另46例胎儿宫内窘迫,导致导常分娩、新生儿生存率低。结论彩色多普勒血流显像对了解胎儿宫内情况有着重要的作用,是产科检查监护中不可缺少的部分。  相似文献   
79.
随着对胃食管反流病研究的深入,大脑和食管感觉及胃排空的相互作用越来越受到重视,功能磁共振成像技术,有助于进一步了解胃食管反流病的发病机制。  相似文献   
80.
目的观察1.5T场强MRI联合动物专用线圈是否可以活体示踪经门静脉移植的纳米级超顺磁性氧化铁颗粒标记的骨髓基质细胞(bone marrow stromal cells BMSCs),为介人性门静脉骨髓基质细胞移植治疗终末期肝脏疾病的研究提供进一步的依据。方法供体大鼠5只,梯度密度离心分离BMSCs,纳米级超顺磁性氧化铁颗粒和脂质体转染BMSCs,体外经普鲁士蓝染色和HE染色确定细胞标记率。受体大鼠15只,分为5组,分别为对照组和纳米级超顺磁性氧化铁颗粒标记的骨髓基质细胞经门静脉移植人正常大鼠肝脏后2h、3d、7d及2周组。1.5T场强MRI联合动物专用线圈行T1W、T2W和T2*序列扫描,观察肝脏信号改变情况,与对照组比较,并且与组织切片对照。结果纳米级超顺磁性氧化铁颗粒和脂质体转染BMSCs,细胞标记率〉95%。经门静脉移植人正常大鼠肝脏后,T2*序列扫描显示经标记的BMSCs在肝内显示弥漫性的结节性低信号影,移植后2h到2周均可见到细胞在受体肝脏内存在,组织学切片显示信号缺失部位与铁颗粒标记细胞相一致。结论纳米级超顺磁性铁氧体颗粒标记的大鼠BMSCs经门静脉移植后可以通过1、5T场强行MRI活体示踪,为临床干细胞移植的应用提供可行的示踪方法。  相似文献   
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