左心房憩室样结构的双源CT成像

目的:利用双源CT血管造影评价左心房憩室样结构的发生率、发生部位及形态学变化。方法:随机搜集的415例成人冠状动脉双源CT血管造影图像进行回顾性分析。结果:发现左心房憩室样结构85例,检出率为20.5%(85/415),总计87个憩室(2例有2个憩室)位于左房上壁77例及下壁8例,憩室底部开口0.5～1.1cm,平均0.8cm,深度0.6～1.2cm,平均0.9cm,底部形态呈尖角状或不规则菜花状。结论:双源CT血管成像能够清晰显示左心房憩室的发生部位及形态变化,有利于临床进行电生理治疗的术前评估。     

双源CT与三维超声心动图对左心房容积及功能评估的比较

目的探讨双源CT(DSCT)对心动周期中不同时相左心房容积和功能的评估价值,并与实时三维超声心动图(RT-3DE)的检查结果进行比较。方法选择2008年6-12月在北京安贞医院进行冠状动脉CT血管造影(CTA)检查的患者50例,男26例,女24例,年龄58±16岁,所有患者均为窦性心律,在同一天完成DSCT和RT-3DE检查,获得左心房、左心室的DSCT容积数据和RT-3DE容积数据,然后分别采用Circulation和Q-LAB心功能分析软件进行数据后处理,获得左心房最大容积(LAVmax)、左心房最小容积(LAVmin)、左心房开始收缩时的容积(LAVp)并计算左心房功能指标,包括左心房射血分数(LAEF)、左心房存储功能(LARV)、左心房被动收缩功能(LAPV)、左心房主动收缩功能(LAAV)和左心房管道功能(LACV)。所有的左心房容积和功能指标都经体表面积校正。DSCT和RT-3DE所得的左心房容积和功能指标的一致性分析采用配对t检验。操作者间的变异性采用Bland-Altman分析和相关性分析。结果通过两种方法获得的体表面积校正的左心房容积和功能结果无显著性差异(P0.05)。与采用RT-3DE相比,DSCT得出的左心房容积和功能指标测量值的变异较低。结论 DSCT在评估冠状动脉的同时可以较准确地测定左房容积和功能。     

对比研究320排动态容积CT与3.O T MRI、超声心动图评价左心室功能的临床价值

目的与3.0 T MRI对比,研究320排动态容积CT及超声心动图(2-dimension echocardiography,2DE)评价左心室功能的准确性。方法选取临床怀疑左心室功能异常的患者64例,在1周内完成320排动态容积CT、3.0 T MRI及2DE 3种影像学检查,对比分析不同检查方法所获得的左心室功能参数:包括射血分数(EF)、舒张末期容积(EDV)、收缩末期容积(ESV)及每搏输出量(SV)。结果 3种影像学检查方法获得的SV值差异无统计学意义(F=0.861,P=0.424);而EF、EDV及ESV值差异均有统计学意义(分别为:F=3.406,P=0.035;F=4.647,P=0.011;F=5.235,P=0.006)。进一步两两对比3种检查方法间的EF、EDV及ESV值:320排CT与3.0 T MRI间的差异均无统计学意义(分别为:P=0.829,P=0.804,P=0.665);320排CT与2DE间的差异均有统计学意义(分别为:P=0.019,P=0.006,P=0.003);2DE与3.0 T MRI间的差异亦均有显著性(分别为:P=0.033,P=0.013,P=0.011)。结论 320排动态容积CT可以准确描述左心室功能,并能较超声心动图更准确地反映左心室功能参数,具有更高的临床应用价值。     

RSNA 2017心脏CT和MRI

【摘要】2017年RSNA关于心脏方面的热点和重点主要包括以下几个方面：①心脏磁共振成像（CMR）定量参数对于非缺血性心肌病的诊断及鉴别诊断; ②心肌炎的诊断及预后;③冠状动脉疾病的低剂量检查及功能性病变诊断; ④CT在心脏瓣膜病术前的应用;⑤先天性心脏病。本文对上述内容进行较全面的综述。     

3TMRI与双源CT评估健康人肺静脉与左心房关系的比较研究

目的比较MRI与双源CT在评估左心房与肺静脉关系中的应用,探讨3T MRI评估左心房与肺静脉关系的可行性。资料与方法于2009年9月至2010年5月纳入健康志愿者64名,其中包括MRI组受试者32名,采用3TMRI全心对比增强成像技术;双源CT组来源于行双源CT冠状动脉成像检查的志愿者,共32名。对MRI及双源CT组图像进行多平面重组(MPR)、容积再现技术(VRT)后处理,观察和测量左心房与肺静脉间的解剖关系。结果组间年龄、性别差异无统计学意义(P>0.05)。两种检查方法中肺静脉无变异,均为4支。右上、左上、左下肺静脉长径、宽径、面积两种方法测量差异无统计学意义(P>0.05)。右下肺静脉长径、宽径两种方法测量差异无统计学意义(P>0.05),面积测量差异有统计学意义(P<0.05)。水平面、冠状面与X轴间夹角,两种检查方法测量差异无统计学意义(P>0.05)。结果 3TMRI在评价左心房与肺静脉间关系上与双源CT有很好的一致性。     

不同对比剂用量方案在双源CT冠状动脉成像及心脏结构显示方面的研究

目的:选择适宜的对比剂用量,改善双源CT冠状动脉成像时对心脏结构的显示能力。方法:160例接受Defini-tion第一代双源CT冠脉CTA检查的患者随机分为4组,对比剂用量分别为:A组=采集时间×注射流速(X ml),B组=(X+5)ml,C组=(X+10)ml,D组=[X+(15～20)]ml。各组均采用碘海醇(350mgI/ml),体质量<75kg者注射流率为4.8～5.0ml/s;体质量≥75kg者注射流率为5.5ml/s。应用Circulation分析软件,采用双盲法评价图像质量。分别测量各组冠状动脉各段、左右心室CT值,观察并记录对比剂伪影及严重程度、对比剂混合液是否均匀、室间隔显示是否清晰等。采用单因素方差分析法(One-way ANOVA)比较组间CT值、图像质量评分等有无差异,采用χ2检验比较室间隔等结构显示情况及对比剂伪影等。结果:各组间一般情况、质量评分、冠脉各段和左心室CT值等差异无统计学意义(P均>0.05)。右心室腔内CT值A、B、C、D组分别为(142.1±35.5)HU、(144.4±43.5)HU、(186.1±66.1)HU、(223.3±119.3)HU,C组与A、B、D组间差异均有统计学意义。各组室间隔尚能分辨(2分)的例数差异无统计学意义,但C、D组显示清晰(3分)的例数多于A、B组;C组条状伪影少于D组。综合分析,C组对比剂方案优于其他组。结论:本研究采用个性化的对比剂方案,对比剂用量=扫描采集时间×流率+10ml,结合患者体质量和体质量指数(BMI)计算对比剂注射流率,可以获得良好的冠脉CTA图像及较为满意的心脏结构、肺动脉显示效果,有一定临床应用价值。     

多层螺旋CT和三维屏气MR冠状动脉成像的对比研究

目的比较16层螺旋CT（16 multi-detector CT,16-MDCT）冠状动脉血管造影（CTA）和三维屏气冠状动脉MR血管造影（MRA）的图像质量以及诊断冠状动脉显著性狭窄（＞50%）的准确性.方法40例疑有冠心病患者在3 d内均行冠状动脉CTA和MRA检查,其中31例患者在2周内行冠状动脉造影检查.将冠状动脉分成9个节段（右冠状动脉近、中、远段,左冠状动脉主干,前降支近、中、远段和旋支近、远段）,由2名影像科医生共同对各个节段的图像质量按0～4级评分,比较CTA和MRA上各个节段的图像质量.以冠状动脉造影为标准,计算并比较CTA和MRA诊断31例冠状动脉显著性狭窄（＞50%）各项准确性指标.结果CTA在右冠状动脉中段的图像质量低于MRA,右冠状动脉近段二者无区别,其他节段均优于MRA.冠状动脉造影显示31例患者共有43个节段狭窄＞50%,CTA和MRA分别正确诊断出36和27个,其敏感性、特异性、阳性预测值和阴性预测值分别为83%、84%、49%、97%和63%、90%、55%、93%.结论除右冠状动脉中段,CTA大部分节段的图像质量优于MRA.CTA诊断冠状动脉显著性狭窄的敏感性高于MRA,但特异性低于MRA.冠状动脉CTA和MRA均表现了较高的阴性预测值,对排除冠状动脉狭窄具有临床价值.     

320排容积CT冠状动脉血管成像在心律失常患者的应用

目的 评价320排CT容积扫描在心律失常(房颤和室性早搏)患者冠状动脉CT血管成像(CTCA)的可行性及其图像质量.方法 31例持续房颤和8例室性早搏患者.经320排CTCA检查.由2名有经验的放射科医师对CT图像质量(4级评分)进行评价,分析图像质量与患者的辐射剂量.2名评价者之间的一致性采用Kappa检验.结果 31例持续房颤和8例室性早搏患者中可评估的冠状动脉血管510段,其中496段(97.2％)达到诊断要求.患者的平均辐射剂量为(12.7±4.8)mSv.2名评价者对冠状动脉评分的一致性较好(Kappa=0.72).结论 房颤和室性早搏患者的CTCA检查具有可行性,心律失常患者可以不作为检查的禁忌证,但仍须进一步降低辐射剂量.     

320排CT评价右心室功能的对照研究:与1.5T磁共振心脏成像比较

目的 与1.5T 磁共振成像对比,探讨320排CT心功能扫描模式(cardiac function angiography,CFA)评价右心室心功能的能力.方法 测量分析50例常规就诊患者应用320排CT CFA扫描数据,与心脏核磁共振成像(cardiac MR imaging,CMR)结果对比,统计分析右室射血分数(right ventricular ejection fraction,RVEF)、右心室舒张末期容积(right ventricular end-diastolic volume,RVEDV)、收缩末期容积(right ventricular end- systolic volume,RVESV)、每搏输出量(right ventricular stroke volume,RVSV)、心排血量 (cardiac output,RVCO)各测量值与CMR各测量值的相关性和差异.结果 (1)与CMR结果对照,320排CT对本组的RVEDV、RVESV 、RVEF、RVSV、RVCO各参数测量结果有显著的相关性(n=50,r=0.944～0.990,P＜0.001).除RVEF测量结果差异无显著性意义外,RVEDV、RVESV、RVSV、RVCO均显示有低估.(2)应用CFA技术,平均延迟时间(9.32±1.77) s,平均射线剂量(2.73±0.47) mSv.结论 应用CFA扫描模式,320排CT可以准确描述右心室功能变化.     

冠状窦及其与左心房肌连接的双源CT冠状动脉成像表现

目的 探讨冠状窦-左心房肌连接的双源CT冠状动脉成像(DSCTCA)形态特征,并评价冠状窦的功能和解剖特点.方法 分析144例受检者(对照组96例,房颤组48例)的DSCTCA影像,通过测量收缩期、舒张期冠状窦横截面积的改变,间接评价冠状窦-右心房肌连接的存在,对冠状窦-左心房肌连接的数量、位置、长度及其与冠状窦形态特点的关系进行研究.连续变量使用t检验,类别变量采用联表的x2检验.结果 (1)冠状窦与二尖瓣环呈平直、轻度弯曲、高位在对照组分别为62、16、18例,在房颤组分别为10、8、30例,2组比较差异无统计学意义(x2=0.093,P=0.954).(2)对照组、房颤组冠状窦长度分别为(34.1±9.1)mm、(33.8±8.9)mm,2组比较差异无统计学意义(t=-0.486,P=0.628).(3)131例(91.0％)可见冠状窦-左心房肌连接,单连接103例,长度为(22.6±12.7)mm,到冠状窦口的距离为(6.3±5.8)mm;双连接28例,近端连接长度为(11.1±3.6) mm,到冠状窦口的距离为(2.1±1.9) mm,远端连接长度为(13.2±6.2) mm,到冠状窦口的距离为(16.7±6.8) mm.对照组、房颤组冠状窦-左心房肌连接的数量、长度差异无统计学意义(P＞0.05).(4)对照组冠状窦从心房舒张期到收缩期,横截面积缩窄约22.4％ (44.5/198.8;t=-21.076,P＜0.01),而房颤组冠状窦从心房舒张期到心房收缩期未见明显收缩(t=0.374,P＞0.05);舒张期房颤组冠状窦横截面积[( 230.4±77.0)mm2]明显大于对照组[(198.8±65.4) mm2;t=-2.579,P＜0.05].对照组9例未显示冠状窦-左心房肌连接患者,均于心房收缩期显示冠状窦收缩,提示冠状窦-左心房肌连接不是冠状窦收缩的主要原因.结论 DSCTCA能清楚显示冠状窦解剖特点,可以了解冠状窦-左心房肌连接的长度、数量和位置.     

3．0T MRI评价中央型肺癌-与常规CT对照

目的：通过与常规CT对照,评价3．0T删对中央型肺癌的显示能力及诊断价值。方法：对21例中央型肺癌行3．0T MRI成像,通过与常规CT对照分析中央型肺癌基本征象包括病灶部位、大小、支气管改变、肺门肿块、阻塞性改变的检出及显示能力。结果：3．0T MRI对显示中央型肺癌病灶部位、大小、支气管改变、肺门肿块的显示能力与CT比较无明显统计学差异（P〉0．05）。3．0TMRI对显示中央型肺癌肿瘤组织与阻塞性病变的改变方面与CT比较有明显统计学差异（P〈0．05）。结论：3．0 T MRI可以较好地显示中央型肺癌的基本征象,可作为影像学检查的一种有效补充手段。     

Minidose技术在双源CT心脏扫描中的初步应用

目的：探讨Minidose技术在双源CT（DSCT）冠状动脉成像及左心室功能分析中的应用价值。方法：45例临床怀疑为冠状动脉心脏病的患者行DSCT冠状动脉成像和超声心动图左心室功能检查。DSCT采用序列扫描模式,总扫描时间窗35％～95％R—R间期,其中40％～70％R-R间期时为全电流输出,数据用于冠状动脉重建,其余间期使用全电流的20％输出,数据用于左心室功能分析。依据美国心脏协会冠状动脉分法,将冠脉图像分为16段,并采用4级法对每段图像质量进行评估。将DSCT检查时测量的左心室射血分数值（LVEF）,并与超声心动图所测得的LVEF值为对照进行统计学分析。结果：40例患者顺利完成DscT冠状动脉成像及超声心动图左心室功能分析。共评价冠状动脉525段,其中可用于诊断的节段占97．53％（512／525）,平均辐射剂量为（3．75±0．89）mSv。DSCT与超声心动图所测得的LVEF值差异无统计学意义（t=-1．61,P=0．12〉0．05）,且两者相关性好（r=0．68）。结论：Minidose技术可以用于DSCT冠状动脉成像兼顾左心室功能分析的“一站式”扫描,冠状动脉图像质量较好,左心室功能分析结果可靠,平均辐射剂量低。     

心房颤动患者的64层螺旋CT冠状动脉成像的初步临床研究

目的 探讨64层螺旋CT在心房颤动患者冠状动脉CT血管成像(CTA)中的应用价值.方法 分析31例心房颤动患者的冠状动脉CTA图像质量,利用血管分析软件判断血管有无狭窄并测量狭窄率,其中10例患者的冠状动脉CTA结果与冠状动脉造影(CAG)结果进行了对照分析.对于不同心率患者图像质量的比较分析采用多个独立样本(等级资料)的非参数秩和榆验.结果所有患者均采用绝对值时间法重组心脏容积数据.对31例患者中364段血管节段进行成像质量分析:心率为47～69次/min组图像质量为优、良、中和差的血管节段数分别为85、41、5和8个,心率为70～79次/min组分别为63、16、13和15个,心率为80～105次/min组分别为46、25、23和24个,3组间成像质量差异有统计学意义(H=22.08,P＜0.01).10例与CAG进行对照,共分析冠状动脉血管125段,CTA诊断血管狭窄程度≥50%的敏感度为85.0%(17/20),特异度为95.2%(100/105),阳性预测值为77.3%(17/22),阴性预测价值为97.1%(100/103).冠状动脉CTA低估了3段血管的病变,过度评价了5段血管.结论64层螺旋CT对心房颤动患者进行冠状动脉CTA检查具有一定的临床价值.     

Dual-source CT coronary angiography in patients with atrial fibrillation: Comparison with single-source CT

Objective

To evaluate the performance of dual-source computed tomography (DSCT) for the visualization of the coronary arteries in a population with atrial fibrillation (AF) compared to single-source CT (SSCT) and to explore the impact of patients’ heart rate (HR) on image quality (IQ) and reconstruction timing.

Methods

Thirty consecutive patients (11 male, 19 female; 69.0 ± 9.2 years old) with suspected coronary artery disease and permanent AF were examined on a DSCT scanner (120 kV, 400 mAs/rot, 0.33 s rotation time, 64 × 0.6 mm collimation, pitch 0.20–0.28, Siemens Somatom Definition). Patients were divided into two groups: low and medium HR group (HR ≤ 80 bpm, n = 14) and high HR group (HR > 80 bpm, n = 16). Five of the patients also underwent conventional coronary angiography (CAG). The raw data from both tube detector arrays were reconstructed as DSCT data using a routine algorithm (temporal resolution of 83 ms). The raw data from one tube detector array was reconstructed separately on the same system using a routine single source algorithm (temporal resolution of 83–165 ms) and defined as virtual SSCT data. Image quality was assessed using a four-point grading scale from excellent (1) to non-assessable (4).

Results

IQ of the DSCT data was significantly better than that of the virtual SSCT data (mean score 1.33 ± 0.61 vs. 1.80 ± 1.02; Z = −8.755, P = 0.000). 98.6% of the segments shown in DSCT were diagnostic, compared with 89.9% of the segments in virtual SSCT, χ² = 32.595, P = 0.000. In DSCT group, IQ of low HR group was also better than that of high HR group, although the difference was not as big (mean score 1.25 ± 0.52 vs. 1.38 ± 0.66; Z = −2.227, P = 0.026). The mean HR of low HR group and high HR group were 67.4 ± 8.5 beats per minute (bpm) and 94.2 ± 8.8 bpm (t = −8.499, P = 0.000). The range of the variation of HR was higher in high HR group than in low HR group (mean difference between maximum and minimum HR 79.5 ± 21.0 vs. 49.9 ± 21.1 bpm; t = −3.845, P = 0.001). In 23 (77%) patients optimal IQ was achieved within one phase for all three main arteries. In low HR group, the optimal phase was distributed evenly between diastole and systole; but in high HR group, the optimal phase shifted to systole in most cases (92%). In five cases these results were compared to CAG results to look for the ability to identify stenosis with a diameter reduction of more than 50% of the lumen. With DSCT it was possible to diagnose 20 of 21 stenosis and 48 of 49 non-stenosed vessel segments correctly. With SSCT 19 of 21 stenosis and 45 of 49 non-stenosed vessel segments were diagnosed correctly according to CAG.

Conclusion

Due to its high temporal resolution, DSCT provides images of full diagnostic image quality in patients with AF, which otherwise would be excluded from CT examinations. The number of assessable segments for DSCT is still somewhat less than in non-AF patients, but in opposition to SSCT still valid for routine diagnostic imaging. Patients’ HR had impact on IQ and reconstruction timing.     

节细胞神经瘤的CT、MRI表现与病理对照分析

目的 分析节细胞神经瘤的CT与MRI表现以及与病理的对照.方法 回顾性分析经手术病理证实的11例节细胞神经瘤的CT与MRI表现及临床病理资料,11例全部行CT检查,其中4例同时行MRI检查.结果 11例节细胞神经瘤大小范围在3cm×4cm×4cm～6cm×7.8cm× 8.5cm之间.肿瘤形态表现为边界清楚的椭圆形肿块,亦可呈不规则形,沿冠状轴生长,可对邻近大血管包绕1/2以上.CT平扫表现为水样至肌肉样密度,多表现低密度,其内散在点状或结节状钙化,不增强或轻度增强居多.MRI T1WI为低信号,T2WI为不均匀混杂信号,但以高信号为主;动态增强扫描中,肿瘤早期不强化,并呈逐渐强化的特征,肿瘤包膜可强化.结论 节细胞神经瘤的CT与MRI表现有一定特征性,并与病理中肿瘤富含大量黏液基质呈相关性.     

眼肌麻痹的CT和MRI研究

目的 回顾性分析眼肌麻痹患者的CT和MRI资料,探讨引起眼肌麻痹的病变发生特点及最佳扫描方案.方法 搜集1376例因眼肌麻痹为主要症状行CT和(或)MRI患者的资料,计算总阳性率及各病变的构成比,比较分析不同检查方法及序列显示海绵窦炎症等病变的情况.统计学分析采用多配对样本的Friedman检验,两两比较采用Wilcoxon检验.结果 影像检查的总阳性率为91.9%(1264/1376),同时行CT和MRI的50例中,MRI阳性率(92.0%,46/50)高于CT(48.0%,24/50)(Z=-4.8,P＜0.01).引起眼肌麻痹的病变:海绵窦区病变552例,占43.7%;眼外肌病变518例,占41.0%;颅眶沟通性病变108例,占8.5%;其他病变86例,占6.8%.对行MRI的283例海绵窦炎症,5种MRI序列显示率差异有统计学意义(χ2=1047.1,P＜0.01);横断薄层T1WI[(2.71±0.69)分]优于横断厚层T2WI[(1.67±0.64)分],横断薄层增强T1WI[(3.92±0.27)分]优于横断厚层T2WI,横断薄层增强T1WI优于横断薄层T1WI,横断薄层增强T1WI优于冠状薄层T1WI[(3.10±0.39)分],冠状薄层T1WI优于横断薄层T1WI,冠状薄层T1WI优于横断厚层T2WI,冠状薄层增强T1WI[(3.95±0.22)分]优于横断薄层T1WI,冠状薄层增强T1WI优于横断厚层T2WI,冠状薄层增强T1WI优于冠状薄层T1WI(P值均＜0.01).对动眼神经和外展神经病变,增强MRI阳性率(100%,39/39)高于平扫(82.1%,32/39)(Z=-2.1,P＜0.05).结论 CT和MRI可显示引起眼肌麻痹的病变,MRI是眼肌麻痹患者的最佳影像检查方法.

Abstract：

Objective To analyze the diseases responsible for ophthalmoplegia and determine the optimal technique identifying the lesions. Methods CT and MR imaging findings of 1376 patients with ophthalmoplegia were analyzed. The total positive rate and ratio of the diseases causing ophthalmoplegia were calculated. The efficiency of various methods and sequences was compared in the evaluation of cavernous sinus inflammation and other lesions. Multi-paired samples Friedman test was used to compare five kinds of images from different methods and sequences, and Wilcoxon test was used to compare between every two kinds of images. Results The total positive rate was 91.9% (1264/1376). In 50 patients who underwent both CT and MRI, the positive rate of MRI (92. 0% ,46/50) was higher than that of CT (48.0% ,24/50)(Z = -4. 8, P ＜ 0. 01). There were 552 cases (43.7%) of cavernous sinus lesions, 518 cases (41.0%)of extraocular muscle diseases, 108 cases (8. 5%) of cranio-orbital communicating lesions and 86 patients (6. 8%) of other lesions. The five kinds of images from various methods and sequences had significant difference in the detection of 283 cavernous sinus inflammation (χ2 = 1047. 1, P ＜ 0. 01) cases. Transverse T1WI with thin slice thickness[(2. 71 ± 0. 69)scores]was better than that with thick slice thickness [(1.67 ± 0. 64) scores], contrast transverse T1 WI with thin slice thickness[(3.92 ± 0. 27) scores]was better than transverse T2WI with thick slice thickness, transverse T1WI and coronal T1 WI with thin slice thickness[(3. 10 ± 0. 39) scores]. Coronal T1 WI with thin slice thickness was better than transverse T1 WI with thin slice thickness and transverse T2WI, and the contrast coronal T1WI with thin slice thickness [(3.95 ± 0. 22) scores]was better than transverse T, WI with thin slice thickness, transverse T2 WI and coronal T1WI (P ＜0. 01 separately). The positive rate of enhanced MRI (100% ,39/39) was higher than that of nonenhanced MRI (82. 1% ,32/39) (Z = - 2. 1, P ＜ 0. 05). Conclusion CT and MRI can show the lesions responsible for ophthalmoplegia. MRI is the best examination method in displaying these lesions.     

Quantitative assessment of left ventricular function with dual-source CT in comparison to cardiac magnetic resonance imaging: initial findings

Cardiac magnetic resonance imaging and echocardiography are currently regarded as standard modalities for the quantification of left ventricular volumes and ejection fraction. With the recent introduction of dual-source computedtomography (DSCT), the increased temporal resolution of 83 ms should also improve the assessment of cardiac function in CT. The aim of this study was to evaluate the accuracy of DSCT in the assessment of left ventricular functional parameters with cardiac magnetic resonance imaging (MRI) as standard of reference. Fifteen patients (two female, 13 male; mean age 50.8 ± 19.2 years) underwent CT and MRI examinations on a DSCT (Somatom Definition; Siemens Medical Solutions, Forchheim, Germany) and a 3.0-Tesla MR scanner (Magnetom Trio; Siemens Medical Solutions), respectively. Multiphase axial CT images were analysed with a semiautomatic region growing algorithms (Syngo Circulation; Siemens Medical Solutions) by two independent blinded observers. In MRI, dynamic cine loops of short axis slices were evaluated with semiautomatic contour detection software (ARGUS; Siemens Medical Solutions) independently by two readers. End-systolic volume (ESV), end-diastolic volume (EDV), ejection fraction (EF) and stroke volume (SV) were determined for both modalities, and correlation coefficient, systematic error, limits of agreement and inter-observer variability were assessed. In DSCT, EDV and ESV were 135.8 ± 41.9 ml and 54.9 ± 29.6 ml, respectively, compared with 132.1 ± 40.8 ml EDV and 57.6 ± 27.3 ml ESV in MRI. Thus, EDV was overestimated by 3.7 ml (limits of agreement −46.1/+53.6), while ESV was underestimated by 2.6 ml (−36.6/+31.4). Mean EF was 61.6 ± 12.4% in DSCT and 57.9 ± 9.0% in MRI, resulting in an overestimation of EF by 3.8% with limits of agreement at −14.7 and +22.2%. Rank correlation rho values were 0.81 for EDV (P = 0.0024), 0.79 for ESV (P = 0.0031) and 0.64 for EF (P = 0.0168). The kappa value of inter-observer variability were amounted to 0.85 for EDV, ESV and EF. DSCT offers the possibility to quantify left ventricular function from coronary CT angiography datasets with sufficient diagnostic accuracy, adding to the value of the modality in a comprehensive cardiac assessment. The observed differences in the measured values may be due to different post-processing methods and physiological reactions to contrast material injection without beta-blocker medication. S. Busch and T. Johnson contributed equally to this study.     

室管膜母细胞瘤的CT和MRI表现

目的 探讨室管膜母细胞瘤的CT和MRI表现特点及其鉴别诊断.方法 回顾性分析5例经手术病理证实的室管膜母细胞瘤患者的临床及影像学资料,5例均接受MRI平扫及增强扫描,其中2例同时接受CT平扫.结果 5例室管膜母细胞瘤中4例为单发病灶,其中1例发生于右侧额叶,3例发生于脑室内(右侧侧脑室、左侧侧脑室及四脑室各1例).1例为多发病灶,主体位于双侧额叶侵犯胼胝体膝部并脑室及鞍上池多发播散转移.肿瘤体积2.6 cm ×2.4 cm×3.4 cm～5.7 cm×5.6 cm×5.4 cm.CT平扫1例发生于左侧侧脑室内病灶表现为大片状钙化,边界清晰,瘤周无水肿,另1例发生于双侧额叶病灶表现为不均匀稍高密度,边界不清,可见大片水肿.MRI平扫T1WI多表现为等稍低信号,T2 WI呈不均匀高信号,增强扫描呈均匀或不均匀强化,3例见肿瘤内囊变.结论 CT和MR检查能准确显示室管膜母细胞瘤部位、范围及周围受累情况,但是影像学表现无特异性,定性诊断有赖于病理检查.