比较3D-FLAIR图像与hT2W-3D-FLAIR序列不同反转时间融合图像评估梅尼埃病膜迷路积水

目的 比较三维液体衰减反转恢复序列（3D-FLAIR）图像与重T2三维液体衰减反转恢复序列（hT2W-3D-FLAIR）融合图像评估梅尼埃病膜迷路积水的价值。方法 对40例单侧梅尼埃病患者经静脉注射钆对比剂后采集内耳3D-FLAIR及hT2W-3D-FLAIR（TI=2 050 ms、2 250 ms）图像，经后处理获得hT2W-3D-FLAIR融合图像，对比观察3D-FLAIR图像与融合图像显示膜迷路积水的效果。结果 3D-FLAIR图像及融合图像中，内淋巴区域均表现为低信号，充盈钆对比剂外淋巴均呈高信号；周围骨骼和空气在3D-FLAIR图像上为低信号，而在融合图像上呈等信号。融合图像可更准确地区分内、外淋巴与周围骨骼及空气的边界，显示耳蜗基底转、中转及顶转膜迷路积水患耳数量均高于3D-FLAIR图像（χ²=3.864、13.393、21.646，P均<0.05），而显示前庭膜迷路积水患耳数量与3D-FLAIR图像差异无统计学意义（χ²=0，P=1.00）。结论 相比3D-FLAIR图像，hT2W-3D-FLAIR融合图像评估梅尼埃病膜迷路积水更具有优势。     

内耳内淋巴MRI增强诊断膜迷路积水的研究进展

膜迷路积水是许多耳科疾病内耳损伤后相同的病理改变,如梅尼埃病、迟发性膜迷路积水、突发性耳聋伴眩晕,最常见的就是梅尼埃病。目前临床主要通过典型症状及相关耳科检查进行诊断,但诊断的特异性较低。磁共振成像(MRI)具有良好的软组织分辨力,结合多种序列,能够观察活体膜迷路积水,为诊断膜迷路积水提供直观可靠的影像依据。     

梅尼埃病患者前庭及耳蜗内淋巴积水程度与临床分期之间的相关性研究

目的：探讨梅尼埃病患者前庭及耳蜗内淋巴积水程度与临床分期之间的相关性。方法：选取161例梅尼埃病患者共172耳,所有入组患者均注射双倍剂量钆剂并在4 h后行MRI延迟扫描,同时患者均行纯音测听(PTA)检查,将患耳PTA检查结果按照中国《梅尼埃病诊断及治疗指南(2017)》标准进行临床分期,平均听阈≤25 dBHL为临床Ⅰ期、平均听阈>25～40 dBHL为临床Ⅱ期、平均听阈>40～70 dBHL为临床Ⅲ期、平均听阈>70 dBHL为临床Ⅳ期。根据Bernaerts等^[3]提出的目测评估方法将耳蜗内淋巴积水程度分为3级、前庭内淋巴积水程度分为4级。最后将前庭及耳蜗内淋巴积水程度与临床分期进行相关性分析。结果：本实验161例患者(共172耳)的前庭与耳蜗内淋巴积水部位所致听力损失程度之间存在显著差异;前庭与耳蜗不同积水程度与梅尼埃患者临床分期之间均存在正相关性(P<0.05)。结论：梅尼埃病患者前庭及耳蜗内淋巴积水部位和积水程度与患者临床分期之间存在相关性,依靠内耳钆造影MRI检查评估的前庭及耳蜗内淋巴积水部位及积水程度变化可以为患者临床分期...     

磁共振增强3D-FLAIR序列诊断耳眩晕患者内耳内淋巴积水

目的 探讨MRI增强3D-FLAIR序列显示耳眩晕（MD）内耳内淋巴积水的价值。方法 在34例患者中筛选57耳,分为MD组、可疑MD组、其他疾病组及正常组。对每耳经咽鼓管咽口注射稀释的马根维显注射液1 ml,24 h后行3D-FLAIR序列扫描。测量并比较各组内淋巴积水的差异;计算该影像方法诊断（可疑）MD的敏感度、特异度。结果 4组平均前庭内淋巴间隙面积的百分比差异有统计学意义（P<0.05）。除MD组与可疑MD组、其他疾病组与正常组外,其他组间两两比较差异均有统计学意义（P均<0.05）。4组间内淋巴积水分级存在差异（P<0.05）;其中MD组与其他疾病组、MD组与正常组、可疑MD组与正常组差异有统计学意义（P均<0.0083）。MRI增强3D-FLAIR序列诊断（可疑）MD的敏感度为77.42%、特异度为80.77%;影像诊断方法与单纯临床诊断（可疑）MD存在相关性（r=0.50）。结论 MRI增强3D-FLAIR能直观显示内耳内淋巴积水及积水程度,是诊断MD、特别是可疑MD的有效影像学方法。     

经鼓室和静脉途径给药后内耳3D-FLAIR MRI观察梅尼埃病迷路变化

目的比较经鼓室和静脉途径给药后三维快速液体衰减反转恢复磁共振成像(3D FLAIR MRI)显示梅尼埃病患者迷路变化的效果。方法将36例单侧梅尼埃病患者随机分成2组,静脉组经肘静脉(n=18)注射对比剂钆贝葡胺(GD-BOPTA),鼓室组(n=18)经双侧鼓膜分别注射等量稀释对比剂钆喷酸葡胺(Gd-DTPA),分别于4 h、24 h后行内耳3D FLAIR MR扫描,观察双侧迷路显影情况;在双侧耳蜗底转及同层脑干区域勾画ROI,分别计算并比较2组耳蜗底转及同层脑干的信号强度比值(CM比值);记录两种方法显示耳蜗、前庭内淋巴积水情况,对比2组CM比值及淋巴积水率差异。结果鼓室组患耳CM比值(1.86±0.74)与健耳CM比值(1.68±0.77)差异无统计学意义(P=0.805)。静脉组患耳CM比值(1.46±0.31)高于健耳(1.26±0.21,P=0.001)。鼓室组患耳CM比值(1.86±0.74)高于静脉组(1.46±0.31,n=18,P=0.044),健耳CM比值(1.68±0.77)高于静脉组(1.26±0.21,n=18,P=0.032)。结论经鼓室给药与静脉途径给药后...     

耳声发射在可疑梅尼埃病诊断中的应用

笔者比较分析了23例首次眩晕发作伴耳鸣、耳闷患者的耳声发射,现报告如下。1对象和方法1.1对象23例首次眩晕发作伴耳鸣、耳闷患者(A组)为2006-01~2007-01我院聋病、眩晕专科门诊患者,年龄35~50(平均39)岁,其中男10例,女13例。另同期在我院神经内科门诊取年龄相仿对照组30例(B组),均为首次眩晕发作不伴耳鸣、耳闷病例。上述所有病例眩晕发作持续时间均超过20min,所有病例均经耳鼻咽喉一般检查已除外长期中耳炎致迷路炎者,并除外突发性聋合并眩晕者[1]。1.2检查方法所有患者就诊当天即进行耳声发射检查,检查仪器为丹麦瑞声达听力集团生产,型…     

三维真实重建反转恢复磁共振成像在梅尼埃病内耳淋巴造影中的诊断价值

目的对比分析钆喷酸葡胺(Gadolinium-diethylene triamine pentaacetic acids,Gd-DTPA)增强的三维液体衰减反转恢复(three-dimensional fluid-attenuated inversionrecovery,3D FLAIR)与三维真实重建反转恢复(three-dimensional real inversionrecovery,3D real IR)磁共振成像(magnetic resonance imaging,MRI)在梅尼埃病内耳内淋巴积水中的诊断价值。材料与方法回顾性分析29例梅尼埃病患者,男10例,女19例,年龄22~71岁,12例为双侧耳发病,17例为单侧耳发病,共患侧耳41只。29例患者均经咽鼓管向中耳鼓室内注入Gd-DTPA稀释液,24 h后行3D FLAIR序列及3D realIR序列MRI内耳造影,在两种序列图像上分别定量测量前庭最大切面及穿过窝轴的耳蜗底旋短轴切面的内淋巴间隙与总淋巴间隙面积比值R(前庭为RV,耳蜗为RC)及定性评估相应内淋巴积水分级G (前庭为GV,耳蜗为GC),比较两组扫描序列图像所测得的RV、RC、GV及GC的差异。结果 29例梅尼埃病患者41只患侧耳中,3D FLAIR与3D real IR两种序列所测得的RV、RC、GC及GV均具有统计学差异性(PRV=0.000,PRC=0.000,PGV=0.000,PGC=0.001),3D real IR序列测得的RV及RC值大于3D FLAIR序列测得值,GV及GC达1~2级(即发现内淋巴积水)患耳数量大于3D FLAIR序列。结论相比于3D FLAIR序列,3D real IR序列内耳造影对于梅尼埃病患者内耳内淋巴积水的检测更敏感,检出率更高。     

原发性椎管内肿瘤的低场MRI诊断与鉴别诊断

目的探讨椎管内原发肿瘤的定位、定性诊断,提高椎管内肿瘤的诊断和鉴别诊断水平。方法回顾性分析71例经手术病理证实的椎管内原发肿瘤的MRI表现,总结椎管内髓内、髓外硬膜下和硬膜外肿瘤的不同MRI特征。结果髓内肿瘤14例,其中室管膜瘤7例,星形细胞瘤5例,血管母细胞瘤2例;髓外硬膜下肿瘤46例,包括神经鞘瘤19例,神经纤维瘤14例,脊膜瘤8例,脂肪瘤3例,表皮样囊肿和畸胎瘤各1例;硬膜外肿瘤11例,其中神经鞘瘤4例,神经纤维瘤3例,血管瘤2例,血管肌肉脂肪瘤和淋巴瘤各1例。71例椎管内肿瘤中,定位准确70例,准确率98.5%;定性准确58例,准确率81.7%。结论 MRI对原发性椎管内肿瘤的诊断定位较容易,根据肿瘤的位置、形态及信号特征结合临床和增强扫描观察,绝大部分肿瘤可作出定性诊断,MRI对椎管内肿瘤的诊断具有重要价值,是目前诊断椎管内肿瘤的首选方法。     

3D FLAIR增强扫描在内耳内淋巴成像中的应用探讨

目的:探讨分析3D FLAIR增强扫描在内耳内淋巴成像中的应用效果。方法:2017年6月-2019年10月,本院收治行内耳内淋巴成像患者25例、健康体检者12例,对患者实施3D FLAIR增强扫描与耳蜗电图检查,对比检测结果。结果:四组的内淋巴积水程度对比存在明显差异(P<0.05)。3D FLAIR增强扫描判断内淋巴积水阳性率与耳蜗电图判断内淋巴积水阳性率存在明显差异(P<0.05)。结论:3D FLAIR增强扫描在内耳内淋巴成像中应用,可辅助临床更快、更准确的检出内耳内淋巴积水,值得在临床推广应用。     

成人型神经元核内包涵体病MRI表现

目的 观察成人型神经元核内包涵体病（NⅡD）MRI表现。方法 回顾性分析5例成人型NⅡD，观察病变位置、形态、信号特点及进展情况。结果 5例NⅡD均有不同程度大脑半球萎缩、侧脑室扩张及Fazekas 2级及以上脑白质病变，弥散加权成像（DWI）可见双侧大脑额叶皮髓质交界区对称性曲线样高信号，表观弥散系数（ADC）图呈低信号；液体衰减反转恢复（FLAIR）序列T2WI中，2例分别于小脑蚓部旁、小脑中脚见对称性片状高信号。治疗后， 1例DWI示双侧大脑额叶皮髓质交接区高信号扩展至双侧顶叶，1例FLAIR-T2WI示小脑蚓部旁高信号范围扩大。结论 DWI大脑额叶皮髓质交界区曲线样高信号为NⅡD的特征性MRI表现，有助于诊断。     

合成MRI联合弥散加权成像及DISCO增强鉴别BI-RADS 4类肿块良恶性

目的 观察合成MRI联合弥散加权成像(DWI)及基于笛卡尔采集的K空间共享三维容积快速动态成像(DISCO)增强扫描鉴别乳腺影像报告和数据系统(BI-RADS)4类肿块良、恶性的价值。方法 回顾性分析79例经穿刺活检或手术病理证实的乳腺肿瘤病灶,术前乳腺合成MRI(采用MAGiC技术)、DWI及DISCO增强图像共诊断89个BI-RADS 4类肿块,包括63个恶性病变(恶性组)及26个良性病变(良性组);比较组间MAGiC参数、表观弥散系数(ADC)、DISCO增强扫描病变形态学特征及时间-强度曲线(TIC)的差异。针对组间差异有统计学意义的参数,分别采用logistic回归分析和受试者工作特征(ROC)曲线评价MAGiC、DWI、DISCO增强参数及三者联合鉴别良恶性BI-RADS 4类肿块的效能。结果 组间病变形态、内部强化特征及TIC、ADC、T2及R2值差异均有统计学意义(P均＜0.05),其余参数差异均无统计学意义(P均＞0.05)。经logistic回归分析,基于MAGiC、DWI及增强DISCO建立模型。相关参数中,ADC鉴别BI-RADS 4类肿块的良恶性效能最高,曲线下面积(AUC)为0.845;而MAGIC+ADC+DISCO模型的诊断效能最高,AUC为0.908。结论 合成MRI、DWI及增强DISCO对鉴别BI-RADS 4类肿块良恶性均有一定价值;三者联合诊断效能更佳。     

基于常规MRI图像的纹理分析鉴别:血管周细胞瘤/孤立性纤维瘤与血管瘤型脑膜瘤

目的基于肿瘤全域对比分析颅内血管瘤型脑膜瘤(hemangioma meningioma,HM)与血管周细胞瘤/孤立性纤维瘤(hemanyiopericytoma,HPC)的T1WI、T2WI以及T1增强图像纹理参数的差异,并评估纹理分析方法对两者的鉴别诊断价值。材料与方法回顾性分析经手术及病理证实的8例HPC患者与9例HM患者的临床资料及术前磁共振成像资料。所有患者均行T1WI、T2WI平扫以及T1增强扫描。利用Omni-Kinetics软件后处理后得到3D感兴趣区的T1、T2以及T1增强信号强度直方图信息及其所有纹理参数,进行组间比较,并利用受试者操作特性(receiver operating characteristic,ROC)曲线评价各参数的鉴别诊断效能。结果在T1增强信号强度图像纹理参数中的最小值、平均值、中位数、均方根值、平均差、偏度、均一性、第5、10、25、75、90百分位数,以及T2信号强度图像纹理参数中的偏度、均一性、第5、10、25百分位数、集群阴影、集群突出在两者间差异有统计学意义(P0.05)。利用ROC曲线分析,T2信号中以均一性0.79为阈值鉴别二者诊断能力最佳(曲线下面积=1.00),敏感性及特异性分别为88.9%、100%。结论基于肿瘤全域感兴趣区T2以及T1增强信号强度图像的纹理分析可以为血管周细胞瘤与血管瘤型脑膜瘤之间的鉴别提供更多信息。     

脑干听觉诱发电位与中内耳CT三维重建对婴幼儿听觉通路结构及听力学异常的评估价值

目的:脑干听觉诱发电位各波形反映相应神经核团的电活动,而中内耳三维CT重建可反映中内耳的结构发育情况,观察两者对婴幼儿听觉通路结构异常的评估价值。方法:选择2000-10/2003-05惠州市中心人民医院收治的耳聋患儿20例,年龄≤4岁,首先进行脑干听觉诱发电位检查,提示听觉通路下段异常然后以1.0mm层厚行双耳螺旋CT扫描并对中内耳结构行表面遮盖成像法三维重建,分析中耳听骨链及内耳结构的大小、形态及脑干听觉诱发电位图形中各波潜伏期,峰间潜伏期,波形的可重复性,波Ⅴ反应阈值。结果:纳入分析20例40只耳。①中内耳CT三维重建:20例40只耳中,显示中和/或内耳异常率42%(17/40),其中中耳听骨链异常12耳,表现为慢性中耳炎听骨链异常8耳(胆脂瘤型6耳,肉芽肿型2耳),表现为中耳听骨链异常4耳。内耳先天性发育异常5只耳(表现为半规管发育细小或不全3耳,耳蜗发育不全2耳)。余23只耳未见异常。②脑干听觉诱发电位检查:20例40耳脑干听觉诱发电位表现异常率82.5%(33/40):其中Ⅰ波缺失,余波正常13耳,Ⅰ～Ⅴ波潜伏期缺失20耳。结论:①脑干听觉诱发电位主要是通过短声刺激诱发脑干神经细胞产生电位记录,用于测试婴幼儿耳聋及高危儿,能客观地反映听力和听觉传导通路的病理障碍。②三维CT可更清楚地显示骨、砧骨及其关节的     

Multimodal‐3D imaging based on μMRI and μCT techniques bridges the gap with histology in visualization of the bone regeneration process

Bone repair/regeneration is usually investigated through X‐ray computed microtomography (μCT) supported by histology of extracted samples, to analyse biomaterial structure and new bone formation processes. Magnetic resonance imaging (μMRI) shows a richer tissue contrast than μCT, despite at lower resolution, and could be combined with μCT in the perspective of conducting non‐destructive 3D investigations of bone. A pipeline designed to combine μMRI and μCT images of bone samples is here described and applied on samples of extracted human jawbone core following bone graft. We optimized the coregistration procedure between μCT and μMRI images to avoid bias due to the different resolutions and contrasts. Furthermore, we used an Adaptive Multivariate Clustering, grouping homologous voxels in the coregistered images, to visualize different tissue types within a fused 3D metastructure. The tissue grouping matched the 2D histology applied only on 1 slice, thus extending the histology labelling in 3D. Specifically, in all samples, we could separate and map 2 types of regenerated bone, calcified tissue, soft tissues, and/or fat and marrow space. Remarkably, μMRI and μCT alone were not able to separate the 2 types of regenerated bone. Finally, we computed volumes of each tissue in the 3D metastructures, which might be exploited by quantitative simulation. The 3D metastructure obtained through our pipeline represents a first step to bridge the gap between the quality of information obtained from 2D optical microscopy and the 3D mapping of the bone tissue heterogeneity and could allow researchers and clinicians to non‐destructively characterize and follow‐up bone regeneration.     

Nano assembly and encapsulation; a versatile platform for slowing the rotation of polyanionic Gd3+‐based MRI contrast agents

Encapsulating discrete Gd³⁺ chelates in nano‐assembled capsules (NACs) is a simple and effective method of preparing an MRI contrast agent capable of delivering a large payload of high relaxivity imaging agent. The preparation of contrast agent containing NACs had previously focussed on preparations incorporating GdDOTP^5‐ into the internal aggregate. In this report we demonstrate that other Gd³⁺ chelates bearing overall charges as low as 2‐ can also be used to prepare NACs. This discovery opens up the possibility of using Gd³⁺ chelates that have inner‐sphere water molecules that could further increase the relaxivity enhancement associated with the long τ_R that arises from encapsulation. However, encapsulation of the q = 1 chelate GdDTPA^2‐ did not give rise to a significant increase in relaxivity relative to encapsulation of the outer‐sphere chelate GdTTHA^3‐. This leads us to the conclusion that in the NAC interior proton transport is not mediated by movement of whole water molecules and the enhanced relaxivity of Gd³⁺ chelate encapsulated within NACs arises primarily from second sphere effects. Copyright © 2015 John Wiley & Sons, Ltd.     

Variability of carotid artery measurements on 3-Tesla MRI and its impact on sample size calculation for clinical research

Carotid MRI measurements are increasingly being employed in research studies for atherosclerosis imaging. The majority of carotid imaging studies use 1.5 T MRI. Our objective was to investigate intra-observer and inter-observer variability in carotid measurements using high resolution 3 T MRI. We performed 3 T carotid MRI on 10 patients (age 56 ± 8 years, 7 male) with atherosclerosis risk factors and ultrasound intima-media thickness ≥0.6 mm. A total of 20 transverse images of both right and left carotid arteries were acquired using T2 weighted black-blood sequence. The lumen and outer wall of the common carotid and internal carotid arteries were manually traced; vessel wall area, vessel wall volume, and average wall thickness measurements were then assessed for intra-observer and inter-observer variability. Pearson and intraclass correlations were used in these assessments, along with Bland-Altman plots. For inter-observer variability, Pearson correlations ranged from 0.936 to 0.996 and intraclass correlations from 0.927 to 0.991. For intra-observer variability, Pearson correlations ranged from 0.934 to 0.954 and intraclass correlations from 0.831 to 0.948. Calculations showed that inter-observer variability and other sources of error would inflate sample size requirements for a clinical trial by no more than 7.9%, indicating that 3 T MRI is nearly optimal in this respect. In patients with subclinical atherosclerosis, 3 T carotid MRI measurements are highly reproducible and have important implications for clinical trial design.     

Combining a deformable model and a probabilistic framework for an automatic 3D segmentation of prostate on MRI

Purpose  Accurate localization and contouring of prostate are crucial issues in prostate cancer diagnosis and/or therapies. Although several semi-automatic and automatic segmentation methods have been proposed, manual expert correction remains necessary. We introduce a new method for automatic 3D segmentation of the prostate gland from magnetic resonance imaging (MRI) scans. Methods  A statistical shape model was used as an a priori knowledge, and gray levels distribution was modeled by fitting histogram modes with a Gaussian mixture. Markov fields were used to introduce contextual information regarding voxels’ neighborhoods. Final labeling optimization is based on Bayesian a posteriori classification, estimated with the iterative conditional mode algorithm. Results  We compared the accuracy of this method, free from any manual correction, with contours outlined by an expert radiologist. In 12 cases, including prostates with cancer and benign prostatic hypertrophy, the mean Hausdorff distance and overlap ratio were 9.94 mm and 0.83, respectively. Conclusion  This new automatic prostate MRI segmentation method produces satisfactory results, even at prostate’s base and apex. The method is computationally feasible and efficient.