3.0 T MR对比增强全心冠状血管成像对冠状静脉系统的解剖学研究

目的 探讨3.0 T MR对比增强全心冠状血管成像(CE CMRA)对冠状静脉解剖的研究价值.方法 43例受试者行3.0 T CE CMRA,采用自由呼吸导航门控、心电触发和非选择性反转恢复(IR)准备脉冲的3D扰相位梯度回波(FLASH)序列.采用32通道体部相控阵线圈进行数据获取.冠状静脉的图像质量由4分法进行评价.连续变量表达为(-x)±s,用配对t检验评价CS窦口前后径及上下径的差异.结果 40例受试者成功完成3.0 T CE CMRA检查,其中38例(95.0%)受试者的图像能够进行评价.左心室后静脉(PVLV)及左边缘静脉(LMV)距冠状窦(CS)窦口的距离分别为(3.34±0.90)及(6.12±1.02)cm.CS、后室间静脉(PIV)、PVLV、LMV及前室间静脉(AIV)的平均图像质量得分分别为(4.0±0.0)、(3.4±0.5)、(3.4±0.5)、(3.0±0.8)及(3.3±0.5)分.CS窦口的上下径[(1.10±0.26)cm]大于前后径[(0.83±0.19)cm],差异有统计学意义(t=-4.31,P<0.05).结论 3.0 T MR CE CMRA能够清晰地评价冠状静脉解剖.     

Non invasive cardiac vein mapping: Role of multislice CT coronary angiography

Purpose

Coronary venous anatomy is of primary importance when implanting a cardiac resynchronization therapy device, besides, the coronary sinus can be differently enlarged depending on chronic heart failure. The aim of this study is to evaluate the usefulness of Coronary CTA in describing the coronary venous tree and in particular the coronary sinus and detecting main venous system variants.

Materials and methods

301 consecutive patients (196 ♂, mean age 63.74 years) studied for coronary artery disease with 64 slice Coronary CTA were retrospectively examined. The acquisition protocol was the standard acquisition one used for coronary artery evaluation but the cardiac venous system were visualized. The cardiac venous system was depicted using 3D, MPR, cMPR and MIP post-processing reconstructions on an off-line workstation. For each patient image quality, presence and caliber of the coronary sinus (CS), great cardiac vein (GCV), middle vein (MV), anterior interventricular vein (AIV), lateral cardiac vein (LCV), posterior cardiac vein (PCV), small cardiac vein (SCV) and presence of variant of the normal anatomy were examined and recorded.

Results

CS, GCV, MV and AIV were visualized in 100% of the cases. The LCV was visualized in 255/301 (84%) patients, the PCV in 248/301 (83%) patients and the SCV in 69/301 (23%) patients. Mean diameter of the CS was 8.7 mm in 276/301 (91.7%) patients without chronic heart failure and 9.93 mm in 25/301 (8.3%) patients with chronic heart failure.

Conclusions

Coronary CTA allows non invasive mapping of the cardiac venous system and may represent a useful presurgical tool for biventricular pacemaker devices implantation.     

Situs inversus with congenital absence of left circumflex artery and a superdominant left-sided right coronary artery: A case report

Situs inversus with a coronary artery defect is an extremely rare congenital anomaly, which is often only incidentally detected during cardiac imaging studies, particularly when the patient is complaining of chest pain. We present a case study of a 37-year-old man who presented with a 3-month history of chest pain. A chest X-ray revealed dextrocardia with stomach gas in the lower right diaphragm. A CT examination showed that the right lung had 2 lobes, and the left lung had 3 lobes. This confirmed that the patient had dextrocardia with situs inversus, where the heart, organs and coronary arteries are inverted to the opposite side of the body. It is also known as a mirroring image, as the arrangement of the anatomy is unaffected. The patient''s right coronary artery was prominently inversed to the left side, while the left main coronary artery was inversed to the right side and continued toward the anterior interventricular sulcus, eventually becoming the left anterior descending (LAD) artery. The left circumflex artery was absent in the atrioventricular groove. There was also a plaque in the right-sided LAD with no significant stenosis. The patient received conservative medical therapy and had frequent follow-ups to check for potential complications.     

MDCT evaluation of the cardiac venous system

Purpose

This study was undertaken to evaluate the usefulness of electrocardiographically (ECG)-gated multidetector-row computed tomography (MDCT) for the assessment of the coronary venous system and detection of its anatomical variants, in order to identify those suitable for lead placement in cardiac resynchronisation therapy (CRT).

Materials and methods

We retrospectively examined the coronary MDCT studies of 89 patients (73 males, 16 females, average age 62.5 years, range 31–79) referred for suspected coronary artery disease. The cardiac venous system was assessed in all patients using three-dimensional (3D) postprocessing on a dedicated Vitrea workstation (five patients were excluded from the analysis).

Results

The coronary sinus, the great cardiac vein, the anterior interventricular vein and the middle cardiac vein were visualised in all cases. The lateral cardiac vein was visualised in 56/84 patients (67%) and the posterior cardiac vein in 63/84 patients (75%), never both missing. Along the postero-lateral wall of the left ventricle, only one branch was present in 44 cases, two branches in 21 cases and three or more branches in 19/84 cases (22%). Evaluation of the maximum diameter revealed that the lateral vein was dominant over the posterior vein in 20/40 cases. The small cardiac vein was visualised in 11/84 cases.

Conclusions

MDCT provides good depiction of the cardiac venous system, enabling the study of the vessel course and the identification of anatomical variants. Hence, this imaging technique could be proposed for the preoperative planning of CRT in selected patients.     

Quantification of coronary stenosis by dual source computed tomography in patients: a comparative study with intravascular ultrasound and invasive angiography

Objective

To determine the accuracy of dual-source CT (DSCT) to quantify coronary stenosis compared to intravascular ultrasound (IVUS) and quantitative coronary angiography (QCA).

Methods

21 patients (23 vessels) were examined with DSCT, IVUS and invasive coronary angiography. Coronary minimal luminal diameter (MLD) and area (MLA) were measured in cross-sectional multi-planar reformatted images perpendicular to the vessel long-axis. The vessel cross-sectional area stenosis (MLA/CSA ratio) was calculated. DSCT results were compared with IVUS and QCA.

Results

A good correlation between DSCT and IVUS was noted for diameter and area stenosis (r = 0.69 and r = 0.73), with an overestimation of MLD stenosis by DSCT (+9.1%) and an underestimation of MLA stenosis (−5.8%). For MLD and MLA, high correlation coefficients (r = 0.78 and r = 0.90, respectively) were found between DSCT and IVUS; and the bias was almost zero (−0.41 mm and +0.1 mm², respectively).The correlation between DSCT and QCA was moderate (r = 0.60) for MLD stenosis with minor overestimation by DSCT (+4.0%) and moderate (r = 0.59) for MLD (bias, +0.01 mm).The cross-sectional area stenosis showed a moderate correlation (r = 0.59) between DSCT and IVUS (+0.00).

Conclusions

DSCT allows accurate quantification of coronary stenosis as compared to IVUS. An excellent correlation was found for the MLA between DSCT and IVUS.     

肝内门静脉和肝静脉的解剖与变异(三维动态增强磁共振血管成像分析)

目的用三维动态增强磁共振血管成像（３ｄｉｍｅｎｔｉｏｎａｌｄｙｎａｍｉｃｃｏｎｔｒａｓｔｅｎｈａｎｃｅｄＭＲＡ,３ＤＤＣＥＭＲＡ）前瞻性地观测肝内门静脉（简称门脉）和肝静脉的解剖和变异。方法共进行１４２例门脉和肝静脉３ＤＤＣＥＭＲＡ检查。对肝内门脉和肝静脉的解剖和变异做分型,计算每一型所占总调查人数的比例,并计算右后下肝静脉的显示率。结果１４２次成像中,８例（５．６％）显示门脉呈三分叉状,７例（４．９％）门脉先分出右后支,然后上行分为左支和右前支,４例（２．８％）门脉右前支源于左支,未发现有门脉左支水平段或右支缺如,余下１２３例（８６．６％）显示正常门脉分支。绝大多数情况下（９５．１％）肝中、肝左静脉合并,而三大支肝静脉单独汇入下腔静脉仅占４．９％。右后下肝静脉的显示率为７．７％。结论肝内门脉变异并不少见。肝中和肝左静脉多合并后汇入下腔静脉。部分病人有较为粗大的右后下肝静脉。３ＤＤＣＥＭＲＡ能方便而清楚地显示上述血管的解剖和变异     

An unusual case of coronary artery fistula to the pulmonary artery,diagnosed with 64-MDCT coronary angiography

This report describes a case of complex coronary–pulmonary artery fistula with one feeding vessel from the proximal part of the right coronary. The complex anatomy of the fistula was shown in detail by multidetector computed tomography using multiplanar reconstruction and 3D volume rendering techniques.Traditionally, conventional angiography has been used for the diagnosis of coronary anomalies. With more frequent use of 64-row multi-detector computed tomography (CT) in chest and cardiac imaging, the number of incidentally found coronary artery fistulas has been increasing.     

Coronary anomalies assessed by whole‐heart isotropic 3D magnetic resonance imaging for cardiac morphology in congenital heart disease

Purpose

To determine the value of whole‐heart three‐dimensional magnetic resonance imaging (MRI) for coronary artery imaging in children/adolescents with congenital heart disease (CHD).

Materials and Methods

Forty children/adolescents (median age: 14 years, range 2.6–25.8) with CHD underwent free‐breathing navigator‐gated isotropic three‐dimensional steady‐state free‐precession (3D‐SSFP) MRI for cardiac morphology. Two observers independently evaluated visibility of origin, course, vessel lengths, image quality (IQ), and contrast between coronary lumen and myocardium. A subgroup was compared with cardiac catheter.

Results

The total scan time was 6.3 ± 3.2 minutes (mean ± SD, at mean heart rate 76 ± 15/min). The mean vessel length for right coronary artery (RCA) by observer 1 was 97 ± 43 mm (observer 2: 94 ± 37 mm), for left main and anterior descending artery (LM/LAD) 91 ± 40 mm (observer 2: 90 ± 40 mm), and for left circumflex artery (LCX) 64 ± 28mm (observer 2: 66 ± 28 mm). The mean vessel contrast was 0.34 ± 0.05 (range: 0.23–0.45; maximum = 1, minimum = 0). On a 4‐level score (1 = nondiagnostic, 4 = excellent), mean IQ scores ranged between 2.3–2.9 (±0.8–1.0). Both observers agreed on the presence/proximal course of RCA in 40/40, LM/LAD in 38/40, and LCX in 36/40 patients. There was complete agreement with invasive coronary angiography available in 12/40 patients (six anomalies).

Conclusion

Isotropic whole‐heart 3D‐MRI for cardiac morphology allows reliable discrimination between normal and abnormal coronary anatomy in children/adolescents with CHD. J. Magn. Reson. Imaging 2009;29:320–327. © 2009 Wiley‐Liss, Inc.     

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。     

用64层CT血管成像探讨冠状静脉系统的解剖特征

目的 研究64层螺旋CT在冠状静脉系统成像中的价值及冠状静脉窦(CS)及其属支的CT影像特征.方法 利用64层螺旋CT进行300例受检者的冠状静脉成像,观测CS及其属支的形态、数目、直径、角度及相邻冠状动脉的伴行关系.以年龄、性别及有无冠心病作为可能的影响因素对各冠状静脉主要分支的直径进行析因设计的方差分析.结果 所有受检者均可见CS、心大静脉(GCV)及心中静脉(MCV),273例受检者(91.0%)可见1～3支PVLV,心小静脉(SCV)及左房斜静脉分别显示56例(18.7%)、24例(8.0%).3例显示永存左上腔静脉畸形引流,1例显示CS憩室.后降支(PDA)与MCV伴行189例(63.0%),相交96例(32.0%).左旋支(LCX)与CS伴行122例(40.7%),与MCV相交15例(5.0%),LCX与PVLV相交104例(34.7%).CS口(CSO)、MCV、PVLV 3项指标,不存在年龄、性别及有无冠心病之间的交互作用,不同年龄、性别或有无冠状动脉疾患组的CSO前后径、MCV及PVLV值差异无统计学意义(P＞0.05).男性与女性的CSO上下径差异有统计学意义(F=6.67,P＜0.05).结论 冠状静脉系统解剖变异较大,64层螺旋CT可以作为显示CS及其属支的无创检查方法,可为心脏电生理治疗提供有用信息.     

Acquired left coronary artery fistula draining to the cardiac vein system after acute myocardial infarction revealed by CT scan

Coronary artery fistula (CAF) is a congenital condition characterized by a pathological communication between a coronary artery and a systemic vein or one of the cardiac chambers. Iatrogenic CAFs were reported to develop secondary to the rupture of coronary aneurysm. Instances of acquired CAF draining into the cardiac chambers have been described after acute myocardial infarction. Angiography is the gold standard in diagnosing CAF. We describe the case of a patient who developed a fistula draining into the middle cardiac vein on the posterior interventricular sulcus, after acute myocardial infarction, revealed by CT scan.     

Dual-source CT cardiac imaging: initial experience

The relation of heart rate and image quality in the depiction of coronary arteries, heart valves and myocardium was assessed on a dual-source computed tomography system (DSCT). Coronary CT angiography was performed on a DSCT (Somatom Definition, Siemens) with high concentration contrast media (Iopromide, Ultravist 370, Schering) in 24 patients with heart rates between 44 and 92 beats per minute. Images were reconstructed over the whole cardiac cycle in 10% steps. Two readers independently assessed the image quality with regard to the diagnostic evaluation of right and left coronary artery, heart valves and left ventricular myocardium for the assessment of vessel wall changes, coronary stenoses, valve morphology and function and ventricular function on a three point grading scale. The image quality ratings at the optimal reconstruction interval were 1.24±0.42 for the right and 1.09±0.27 for the left coronary artery. A reconstruction of diagnostic systolic and diastolic images is possible for a wide range of heart rates, allowing also a functional evaluation of valves and myocardium. Dual-source CT offers very robust diagnostic image quality in a wide range of heart rates. The high temporal resolution now also makes a functional evaluation of the heart valves and myocardium possible.     

三维增强磁共振血管成像在肝移植中的临床应用

目的:探讨三维增强磁共振血管成像(3D CE-MRA)对原位肝移植(OLT)出入肝脏的血管进行术前评估及术后监测的价值.方法:回顾性分析我院肝移植患者术前20例及术后13例患者的3D CE-MRA图像,包括血管主干及其分支的显示、癌栓及血管狭窄的情况.结果:所有患者3D CE-MRA检查均获成功,其MRI图像重组后可以很好地显示肝动脉、肝静脉、门静脉及下腔静脉的走行、癌栓及血管变异情况.结论:3D CE-MRA具有无创、安全、快捷、准确、无辐射等优点,是原位肝移植术前评估及术后监测的首选检查方法.     

双源CT自适应前瞻性心电门控冠状动脉成像技术的初步应用

目的：初步探讨双源CT前瞻性心电门控冠状动脉成像的图像质量和辐射剂量。方法：对50例临床怀疑冠心病的受检者进行双源CT自适应前瞻性门控冠状动脉成像,检查前均未服用琥珀酸美托洛尔。图像质量分4级,依照美国心脏病协会（AHA）冠状动脉分段标准分别评价各个冠状动脉节段的图像质量,分别计算每例的有效辐射剂量（ED）。结果：50例受检者平均体重指数（BM I）为（25.00±2.58）kg/m2,扫描时平均心率（71.13±9.63）次/min,平均有效辐射剂量（3.31±1.08）mSv,显示了94.76%能满足诊断要求的冠状动脉节段,图像质量优秀占79.49%。结论：双源CT自适应前瞻性心电门控冠状动脉成像对于无严重心律失常的受检者都可得到满足诊断要求的图像,辐射剂量低,具有广阔的应用前景。     

Evaluation of intraportal venous flow distribution by unenhanced MR angiography using three‐dimensional fast spin‐echo with a selective tagging pulse: Efficacy of subtraction of tag‐on and tag‐off images acquired during a single breath‐hold

Purpose

To evaluate the efficacy of subtracted MR images from two sets of unenhanced three‐dimensional (3D) MR angiography data (tag‐on and tag‐off images) acquired simultaneously during a single breath‐hold in assessing the intraportal venous flow distribution to the distal branches from the superior mesenteric vein (SMV) and the splenic vein (SpV).

Materials and Methods

Tag‐on and tag‐off MR images during a single breath‐hold were obtained in 25 normal subjects. Tagging pulse was placed on the SMV or SpV separately to study inflow correlation of tagged blood into the portal vein.

Results

On the MR images tagged on the SMV, the mean ratings of visibility of tagged blood flow on the subtracted images were significantly higher (P = 0.016–0.0001) than those on the source images in almost all branches except second‐ordered left portal vein (P = 0.096). On the subtracted MR images tagged on SMV, the tramline (16 of the 25 subjects) was the most common distribution pattern of the tagged blood inflow in the main portal vein.

Conclusion

Subtracted MR images from two sets of unenhanced 3D MR angiography data (tag‐on and tag‐off images) acquired simultaneously would be effective to show the blood flow distribution of tagged blood into the portal vein and distal branches from SMV and SpV under the physiological condition without contrast injections. J. Magn. Reson. Imaging 2009;29:1224–1229. © 2009 Wiley‐Liss, Inc.     

Update on multidetector coronary CT angiography of coronary stents: in vitro evaluation of 29 different stent types with dual-source CT

The aim of this study was to test a large sample of the latest coronary artery stents using four image reconstruction approaches with respect to lumen visualization, lumen attenuation, and image noise in dual-source multidetector row CT (DSCT) in vitro and to provide a CT catalogue of currently used coronary artery stents. Twenty-nine different coronary artery stents (19 steel, 6 cobalt-chromium, 2 tantalum, 1 iron, 1 magnesium) were examined in a coronary artery phantom (vessel diameter 3 mm, intravascular attenuation 250 HU, extravascular density −70 HU). Stents were imaged in axial orientation with standard parameters: 32 × 0.6 collimation, pitch 0.24, 400 mAs, 120 kV, rotation time 0.33 s. Image reconstructions were obtained with four different convolution kernels (soft, medium-soft, standard high-resolution, stent-dedicated). To evaluate visualization characteristics of the stent, the lumen diameter, intraluminal density, and noise were measured. The stent-dedicated kernel offered best average lumen visualization (54 ± 8.3%) and most realistic lumen attenuation (222  ± 44 HU) at the expense of increased noise (23.9 ± 1.9 HU) compared with standard CTA protocols (p < 0.001 for all). The magnesium stent showed the least artifacts with a lumen visibility of 90%. The majority of stents (79%) exhibited a lumen visibility of 50–59%. Less than half of the stent lumen was visible in only six stents. Stent lumen visibility largely varies depending on the stent type. Magnesium is by far more favorable a stent material with regard to CT imaging when compared with the more common materials steel, cobalt-chromium, or tantalum. The magnesium stent exhibits a lumen visibility of 90%, whereas the majority of the other stents exhibit a lumen visibility of 50–59%. David Maintz and Matthias Burg contributed equally to this publication.     

Portal venous system: evaluation with unenhanced MR angiography with a single-breath-hold ECG-synchronized 3D half-Fourier fast spin-echo sequence

OBJECTIVE: Eighteen healthy persons underwent unenhanced MR angiography with a breath-hold ECG-synchronized 3D half-Fourier fast spin-echo technique to evaluate the visibility of the portal vein and its branches. CONCLUSION: Our results indicated that unenhanced MR angiography with a singlebreath-hold ECG-synchronized 3D half-Fourier fast spin-echo sequence facilitates precise visualization of the anatomic features of the portal vein and its branches without the use of contrast agents.     

Dual-source cardiac computed tomography: image quality and dose considerations

Computed tomography (CT) imaging of the heart, most prominently coronary CT angiography, is currently subject to intense interest and is increasingly incorporated into clinical decision-making. In spite of tremendous progress in CT technology over the past decade, the limited temporal resolution has remained one of the most severe problems, especially for cardiac imaging. The novel design concept of dual-source CT (DSCT) allows for an effective scan time of 83 ms independent of heart rate. While large trials are still missing, initial studies have shown improved image quality, especially for visualizing the coronary arteries and detecting coronary artery stenoses. Further investigations have shown that routine beta blockade to lower the heart rate is not necessary to reliably achieve diagnostic image quality. Other applications that may particularly benefit from increased temporal resolution are the analysis of ventricular function and of the cardiac valves. Dose issues which are of interest for cardiac CT in general are discussed in some detail, including a quantitative analysis of dose values and three-dimensional dose distributions. Various strategies to lower radiation exposure are available today, and DSCT offers specific potential for this.     

室性期前收缩对双源CT冠状动脉成像的影响及心电编辑的应用

目的 探讨室性期前收缩(premature ventricular contractions,PVC)对冠状动脉双源CT血管成像(DSCTA)图像质量的影响以及心电编辑在PVC患者中的应用价值.资料与方法 对36例实施冠状动脉DSCTA过程中出现PVC患者进行回顾性分析,另选取39例窦性心律患者作为对照.冠状动脉图像采用4分法进行分段图像质量评分.PVC组患者按早搏发作频次分为单发、2个、3个及3个以上4组.比较PVC组与对照组,对室性早搏频次分组及其编辑前后的图像质量评分进行分析.分析室性早搏频次与平均图像质量评分之间的相关性.结果 PVC组患者总体图像质量评分明显低于对照组(x2=265.444,P<0.001).图像质量评分与室性早搏发作频次呈负相关(r＝-0.700,P<0.01).PVC患者编辑后图像质量评分明显高于编辑前.结论 PVC对冠状动脉DSCTA有影响.心电编辑技术能够明显改善室性早搏患者的冠状动脉成像质量.