双对比钡餐造影对早期胃癌的诊断价值

目的探讨早期胃癌的双对比钡餐造影的特征及其临床诊断价值。方法对我院放射科在2003年1月至2007年12月间38例经手术或胃镜取病理证实早期胃癌在术前接受双对比钡餐造影X线检查进行回顾性分析。本组患者在检查时采用多体位、多轴位观察黏膜像及充盈像,并摄片,必要时使用压迫器。结果38例早期胃癌,位于胃窦部21例,胃角8例,胃体部5例,胃底部4例,Ⅰ型11例,Ⅱc型7例,Ⅱa＋c型6例,Ⅲ型14例。高分化腺癌10例,低分化腺癌6例,粘液腺癌7例,印戒细胞癌5例,中分化管状腺癌10例。11例结节状隆起型,13例表浅型,14例凹陷型。结论优良的双对比钡餐造影法是将粘膜法、充盈法和压迫法充分结合,并利用体位进行检查,它有助于检出早期胃癌。     

结肠双重造影同步排粪造影42例分析

目的：评价结肠气钡双重造影同步排粪造影的可行性。方法：自近两年需做钡灌肠检查加排粪造影检查的108人次中随机抽取42人实施结肠气钡双重造影同步排粪造影,并就各项指标进行对比检验。结果：108例中男22例,女86例;年龄2－73（平均42．93）岁。同步造影42例中男10例,女32例。分别检测组和同步造影组的七种常见疾病的阳性率分别为：直肠前突60．61％和61．90％;直肠黏膜税垂72．73％和64．28％;直肠黏膜套迭46．97和35．71％;耻骨直肠肌综合征,27．28％和37．10％;乙状结肠内疝18．18％和16．67％;盆底下降22．73％和21．40％;骶直分离12．12％和7．14％;小肠疝：0和9％;小肠下垂：0和7％。结论：结肠气钡双重造影同步排粪造影与排粪造影比较排粪障碍病变的显示率大致相同。前者的优点是一次检查可了解结肠病变和排粪障碍病变。     

良性前列腺增生超声造影的初步研究

目的:分析并评价BPH的超声造影表现,探讨超声造影对研究BPH血流灌注的价值。方法:对48例经直肠超声引导下穿刺活检、病理证实为BPH的患者进行超声造影检查,观察前列腺内腺及外腺的超声造影表现并制作时间-强度曲线,分析超声造影开始增强时间、造影开始减退时间、造影剂渡越时间及峰值强度。结果:前列腺为富血供器官,造影增强明显。48例BPH患者前列腺内腺及外腺开始增强的时间分别为(26.68±3.76)、(31.24±5.33)s,内腺开始增强的时间显著早于外腺,尤以尿道周围区及内腺的包膜处明显(P=0.000);内腺及外腺造影剂完全退出时间分别为(200.68±59.40)、(157.56±50.66)s,内腺造影剂完全退出时间显著晚于外腺(P=0.000);内腺及外腺造影剂渡越时间分别为(173.94±60.14)、(129.21±56.91)s,内腺造影剂渡越时间显著长于外腺(P=0.000)。内腺及外腺造影峰值强度分别为(90.45±42.19)、(65.32±25.15)dB,内腺造影峰值强度显著高于外腺(P=0.000)。结论:超声造影检查能够连续观察BPH的血流灌注情况,有望成为研究BPH血流状况的有效方法。     

携P-选择素抗体靶向微泡评价大白兔睾丸缺血/再灌注损伤的实验研究

目的:探讨携P-选择素抗体靶向脂质微泡评价睾丸完全缺血/再灌注损伤的可行性。方法:制备普通脂质微泡(MB)和携P-选择素抗体靶向微泡(MBp)。30只大白兔随机分成对照组、缺血/再灌注损伤(IRI)0.5 h组、1 h组、2 h组、4 h组,每组6只,在缺血/再灌注术后行MB和MBp的双侧睾丸造影(间隔20 min),经过4～5 min待健侧睾丸实质中MB或MBp完全消失,测量术侧睾丸第一帧超声造影的声强度(F-P,10-5AU)。随后将术侧睾丸取下行免疫组化分析。结果:MBp造影图像显示各IRI组术侧睾丸F-P值分别大于各组的MB(P均0.05),并在2 h[MBp(8.34±1.20)10-5AU,MB(1.87±0.25)10-5AU]最高。对照组术侧睾丸MB、MBp声强度未见明显差异(均为0 AU)(P0.05)。免疫组化示对照组睾丸血管内皮无明显P-选择素表达,而IRI组P-选择素表达增加,并随时间延长而增多。结论:携P-选择素抗体靶向微泡超声造影能够评价睾丸IRI的炎症反应。     

经颅彩色编码超声及经颅超声造影观察颅内静脉窦血栓

目的探讨经颅彩色编码超声(TCCS)及经颅超声造影(CE-TCCS)诊断颅内静脉窦血栓(CVST)及大脑大静脉、基底静脉的血流动力学变化的价值。方法选取经DSA和/或MR静脉血管成像(MRV)确诊为颅内横窦和/或直窦血栓的22例患者为CVST组,行TCCS及CE-TCCS;以同期因其他疾病就诊的68例患者为对照组,行TCCS;对比观察2组大脑大静脉、基底静脉及静脉窦的显示率和血流动力学变化。结果 CVST组中,TCCS诊断直窦血栓13例,左侧横窦血栓20例,右侧横窦血栓17例,与DSA和/或MRV结果比较差异有统计学意义(P均0.05);经CE-TCCS判定直窦血栓5例,左侧横窦血栓14例,右侧横窦血栓9例,与DSA和/或MRV结果比较差异均无统计学意义(P均0.05)。CVST组较对照组大脑大静脉、双侧基底静脉显示率及峰值血流速度均增高(P均0.05)。结论 CE-TCCS诊断CVST与DSA和/或MRV相似。TCCS可显示静脉窦血栓形成后的大脑大静脉、基底静脉;静脉流速升高可提示CVST形成可能。     

同步辐射X线相衬成像对裸鼠胰腺癌的早期诊断

目的 通过建立裸鼠胰腺癌模型,结合磁共振成像（magnetic resonance imaging,MRI）,探讨同步辐射X线相衬成像技术对胰腺癌的早期诊断。方法 32只nu/nu雌鼠,采用数字表法随机分为A、B两组：A组（n=24）为人胰腺癌细胞PANC-1胰腺原位移植瘤组,即于胰腺被膜下注射10⁸×2 μL单细胞悬浮液;B组（n=8）为空白对照组,即于胰腺被膜下注射2 μL 0.9%（质量浓度）氯化钠注射液。再根据术后1、2、3、4周处理时间的不同,将A、B两组分为4个亚组,即A1、A2、A3、A4（n=6）和B1、B2、B3、B4（n=2）。术后分别行MRI扫描、肿瘤标本相衬成像及病理学检查。结果 ①A组术后平均成瘤率73%（16/22）,术后4周成瘤率最高,达到100%,成瘤率随观察时间的延长而升高,二者之间存在线性趋势关系（χ_线性趋势²=4.718,P=0.030）;病理组织学检查为胰腺低分化腺癌。②同步辐射X线相衬成像可显示直径为0.5 mm的胰腺原位肿瘤,早期（两周）的灵敏度和特异度达到100%,明显高于MRI扫描（P=0.029）。结论 PANC-1细胞原位移植是建立裸鼠胰腺癌模型的可靠方法;与MRI相比,同步辐射X线相衬成像能发现胰腺癌微小病变,有可能为胰腺癌的早期诊断提供了一种全新的技术手段。     

肝脏渡越时间在门静脉高压-食管胃底静脉曲张患者门静脉压力评估中的应用

目的：分析肝脏渡越时间与门静脉高压-食管胃底静脉曲张患者门静脉压力的关系,阐明其临床意义。方法：选择因门静脉高压-食管胃底静脉曲张行食管胃底曲张静脉栓塞术患者50例作为观察组,选择无肝病病史及肝病临床表现患者（住院或门诊）50例作为对照组。2组患者均行肝脏超声造影,观察组患者在超声引导下行门静脉穿刺时建立手术通路并测量自由门静脉压（FPP）。比较2组患者肝动脉-肝静脉渡越时间（HA-HVTT）、肝门静脉-肝静脉渡越时间（PV-HVTT）和肝实质-肝静脉渡越时间（PA-HVTT）,分析观察组患者HA-HVTT、PV-HVTT、PA-HVTT与FPP的相关性。结果：与对照组比较,观察组患者HA-HVTT、PV-HVTT和PA-HVTT均明显缩短（t=5.078,P<0.01;t=12.163,P<0.01;t=2.649,P<0.01）;观察组患者HA-HVTT、PV-HVTT、PA-HVTT与FPP均呈负相关关系（r=-0.799,P<0.01;r=-0.554,P<0.01;r=-0.735,P<0.01）。HA-HVTT与FPP线性关系为Y=-0.410X+7.254,PV-HVTT与FPP线性关系为Y=-0.355X+4.983,PA-HVTT与FPP线性关系为Y=-0.566X+4.997。结论：肝脏渡越时间可以成为判断门静脉压力的有效指标,为门静脉高压患者的诊断和治疗提供理论依据。     

MRI detection of myocardial perfusion defects due to coronary artery stenosis with MS-325

PURPOSE: To assess the value of an intravascular, albumin-targeted contrast agent, MS-325, in visualizing myocardial ischemia with magnetic resonance imaging (MRI). MATERIALS and METHODS: Left anterior descending coronary artery (LAD) stenosis was created in 19 pigs using a closed-chest modified angioplasty technique. Myocardial ischemia was detected by first-pass, contrast-enhanced MRI at peak dipyridamole stress and was compared to Technetium-99m (Tc-99m) sestamibi single photon emission computed tomography (SPECT). Regional coronary blood flow was determined using microspheres. RESULTS: Inducible myocardial ischemia with >40% reduction in stress myocardial blood flow was created in eight animals. An MRI defect, classified as > or=75% reduction in peak myocardial signal intensity in the affected territory, was detected in 92.3% of these animals. In the presence of mild coronary stenosis, there was uniform enhancement with MRI and tracer uptake by SPECT. Concordance of MRI and SPECT for detecting perfusion defects was 85%. CONCLUSION: The pattern of prolonged and persistent MR hypoenhancement of the ischemic myocardial bed using MS-325, which is retained primarily in the vascular bed due to its albumin-binding properties, facilitates the detection of myocardial perfusion defects.     

High temporal resolution phase contrast MRI with multiecho acquisitions.

Velocity imaging with phase contrast (PC) MRI is a noninvasive tool for quantitative blood flow measurement in vivo. A shortcoming of conventional PC imaging is the reduction in temporal resolution as compared to the corresponding magnitude imaging. For the measurement of velocity in a single direction, the temporal resolution is halved because one must acquire two differentially flow-encoded images for every PC image frame to subtract out non-velocity-related image phase information. In this study, a high temporal resolution PC technique which retains both the spatial resolution and breath-hold length of conventional magnitude imaging is presented. Improvement by a factor of 2 in the temporal resolution was achieved by acquiring the differentially flow-encoded images in separate breath-holds rather than interleaved within a single breath-hold. Additionally, a multiecho readout was incorporated into the PC experiment to acquire more views per unit time than is possible with the single gradient-echo technique. A total improvement in temporal resolution by approximately 5 times over conventional PC imaging was achieved. A complete set of images containing velocity data in all three directions was acquired in four breath-holds, with a temporal resolution of 11.2 ms and an in-plane spatial resolution of 2 mm x 2 mm.     

Combined time-resolved and high-spatial-resolution 3D MRA using an extended adaptive acquisition

PURPOSE: To combine the benefits of time-resolved dynamic imaging and single elliptical centric acquisitions in a reasonable scan time. MATERIALS AND METHODS: A time series of images with moderate spatial resolution was acquired using the 3D Time-Resolved Imaging of Contrast KineticS (3D TRICKS) technique with elliptical centric encoding during contrast arrival. Following venous opacification, a complete large centrically encoded k-space volume was acquired. The high-spatial-frequency portions of this volume were combined with a 3D TRICKS time frame to form a high-resolution image. An additional single image is formed by suppressing background and signal averaging all acquired data, including post-venous low-spatial-frequency data. For this image, 2D temporal correlation analysis is used to suppress low-spatial-frequency vein contributions. Arrival time and spatial correlations are used to suppress background. RESULTS: The 3D TRICKS time frame may be selected to ensure a combined high-resolution image that has optimal central k-space sampling for any vascular region. The single image formed by signal averaging all acquired data has increased contrast-to-noise (CNR) and signal-to-noise (SNR) ratios. CONCLUSION: The advantages of time-resolved and high-spatial-resolution imaging were combined using an extended dual-phase acquisition. Some SNR and CNR gain was achieved by signal averaging. This process is facilitated by background and vein suppression.