Transvaginal color Doppler imaging

Transvaginal color Doppler was used to assess circulation in pelvic vessels in a group of 64 patients including 15 patients with fertility problems, 18 patients with pelvic tumors, 2 cases of suspected ectopic pregnancy, and 29 pregnant patients with fetuses between 6 weeks and 10 weeks, menstrual age. Blood flow was successfully displayed by color Doppler in the external and internal iliac arteries, and the uterine arteries, but flow in ovarian arteries could not be visualized. In the subgroup of patients with pelvic tumors, neovascularization of tumor tissue was documented in 6 out of 10 cases of uterine fibroma and in 2 cases of ovarian cancer. In 6 cases involving benign ovarian pathology, no abnormal blood supply was observed. A comparison between the characteristics of blood flow within uterine fibromas and ovarian malignancies showed lower impedance and higher blood velocity in cases of malignancy. In early pregnancy blood flow in the umbilical artery could be visualized by color Doppler starting from the 6th week and flow in the aorta from the 8th week. Flow in the trophoblasts was observed with an overall success rate of 59% and successfully demonstrated in 1 out of 2 cases of ectopic pregnancy.     

分段读出扩散加权成像在鼻咽癌检查中的价值

目的探讨分段读出扩散加权成像(RS-EPI DWI)相对于单次激发平面回波扩散加权成像(SS-EPI DWI)在鼻咽癌检查中的价值。方法收集30例经病理证实的未做任何治疗的鼻咽癌患者,采用Siemens 3.0 T Skyra磁共振扫描仪对患者常规平扫加增强扫描基础上加做鼻咽的轴位RS-EPI DWI及SS-EPI DWI序列,分别计算出鼻咽肿瘤区域的信噪比(SNR)、对比噪声比(CNR),以T_1增强轴位图像为参考,计算鼻咽层面图像的变形百分比,测量鼻咽肿瘤长、短径,比较SS-EPI DWI、RS-EPI DWI图像上肿瘤大小的准确性,比较颅底层面磁敏感伪影幅度。结果RS-EPI DWI较SS-EPI DWI图像的SNR(t=34.074,P0.01)、CNR(t=23.120,P0.01)值高,图像变形较轻,相同解剖层面,RS-EPI DWI图像测出的肿瘤大小更接近增强后T1轴位上病灶大小,颅底层面RS-EPI DWI图像磁敏感伪影明显较弱(b值为0 s/mm~2时t=10.634,P0.01,b值为1000 s/mm~2时t=8.219,P0.01),两名医师分别对SS-EPI DWI、RS-EPI DWI的ADC图病灶区进行测值,两组测值在判断病灶扩散受限上统计学差异(t=0.00,P=1.000.05)。结论分段读出扩散加权成像较传统的弥散加权成像图像质量更佳,其临床应用更有价值,对于诊断的准确性具有积极的作用。     

生物光声—超声—磁声联合成像的研究进展

生物超声（US）、光声（PA）和磁声（MA）成像均以超声波作为载体,将其结合可获得生物组织的组合图像,充分发挥各成像手段的优势。与单一成像技术相比,联合成像具有更好的分辨率及更高的对比度和敏感度,可更精准地定位病变组织,并辨识出其形态和成分。本文对光声—超声、磁声—超声及磁光声联合成像,尤其内窥式联合成像的研究进展及应用现状进行综述。     

体素内不相干运动成像的原理及前景展望

体素内不相干运动(intravoxel incoherent motion,IVIM)成像是指体素内信号衰减的同时包括真性水分子弥散和毛细血管网中随机血流微循环灌注,它可以更加全面地分析组织扩散成像数据,揭示疾病的病理生理学改变。近年来,IVIM逐渐被应用于临床研究中,在各个器官及系统的疾病诊断中发挥重要作用。     

Multimodality Rodent Imaging Chambers for Use Under Barrier Conditions with Gas Anesthesia

Purpose  The ability to reproducibly and repeatedly image rodents in noninvasive imaging systems, such as small-animal positron emission tomography (PET) and computed tomography (CT), requires a reliable method for anesthetizing, positioning, and heating animals in a simple reproducible manner. In this paper, we demonstrate that mice and rats can be reproducibly and repeatedly imaged using an imaging chamber designed to be rigidly mounted on multiple imaging systems. Procedures  Mouse and rat imaging chambers were made of acrylic plastic and aluminum. MicroCT scans were used to evaluate the positioning reproducibility of the chambers in multimodality and longitudinal imaging studies. The ability of the chambers to maintain mouse and rat body temperatures while anesthetized with gas anesthesia was also evaluated. Results  Both the mouse and rat imaging chambers were able to reproducibly position the animals in the imaging systems with a small degree of error. Placement of the mouse in the mouse imaging chamber resulted in a mean distance of 0.23 mm per reference point in multimodality studies, whereas for longitudinal studies the mean difference was 1.11 mm. The rat chamber resulted in a mean difference of 0.46 mm in multimodality studies and a mean difference of 4.31 mm in longitudinal studies per reference point. The chambers maintained rodent body temperatures at the set point temperature of 38°C. Conclusions  The rodent imaging chambers were able to reproducibly position rodents in tomographs with a small degree of variability and were compatible with routine use. The embedded anesthetic line and heating system was capable of maintaining the rodent’s temperature and anesthetic state, thereby enhancing rodent health and improving data collection reliability.     

背景信号抑制弥散加权成像技术的临床应用

DWIBS是MR成像技术近年来发展的一种新方法.本文对DWIBS的发展、原理及目前在颅脑、神经、胸部、肝脏及腹盆部等部位的临床应用研究进行了全面综述.     

组织谐波成像诊断胰腺占位性病变的临床应用

目的：通过常规基波成像(FI)与组织谐波成像(THI)的对比观察，探讨组织谐波成像在胰腺占位性病变诊断中的价值。方法：对比分折62例胰腺占位病变的基波成像和组织谐波成像的结果。结果：在观察胰腺病灶的边界、内部回声及胰管回声方面，在确定占位性病变的物理性质方面，组织谐波成像优于基波成像。结论：本研究表明，组织谐波成像可提高病变的清晰度及对比度，提高胰腺占位性病变的图像质量，从而提高诊断准确率。     

磁共振成像用于分子影像学研究

分子影像学可广义定义为在活体内进行细胞和分子水平的生物过程描述和测量,而磁共振不仅具有非侵袭性,在活体成像中有着极精细的空间分辨率和极佳的组织分辨率,还可在活体器官的细胞或亚细胞水平定性与定量生物学过程。所以,磁共振技术在分子影像学研究中扮演了极其重要的角色。     

胃癌磁共振扩散加权成像:并行采集联合分次屏气多信号平均技术的临床研究

目的探索实现胃癌磁共振扩散加权成像(DWI)的技术因素,评价胃癌DWI的临床应用价值.方法扩散加权单次激发平面回波成像(SS-EPI)序列连续检查胃癌患者53例,其中前期17例进行ASSET-DWI成像方法研究,结合分次屏气多信号平均技术,以肿瘤显示、伪影分级、对比噪声比(CNR)为评价标准,比较有无ASSET及不同信号平均次数(NEX)与ASSET搭配所得DWI图像的质量,确定成像参数;利用确定序列对后续36例胃癌进行成像研究,确定胃癌及非癌胃壁的DWI影像学表现及ADC值范围.扩散敏感梯度取b=0、1000 s/mm2.结果ASSET-DWI组较无ASSET组成像速度提高,相关伪影(磁敏感伪影、化学位移伪影及Ghost伪影)轻且图像基本无变形(P＜0.01);分次屏气采集对ADC值计算无影响(P＞0.05);分次屏气多信号平均(4 NEX)采集,可基本消除ASSET相关伪影,具备良好的对比噪声比.胃癌癌肿在DWI图上表现为稳定的高信号,平均ADC值为(1.17±0.22)×10-3 mm2/s,非癌胃壁表现为低信号,平均ADC值为(1.94±0.28)×10-3 mm2/s,二者差异有统计学意义(P＜0.01);以ADC值＜1.46×10-3 mm2/s作为判定胃癌的标准,敏感性97.0%,特异性90.9%.结论8通道体部相控阵线圈联合ASSET技术及分次屏气多信号平均采集,实现了胃癌高b值扩散加权成像;ADC值可作为胃癌诊断的辅助指标.     

急性睾丸扭转行核素阴囊显像1例

患者男,17岁,主诉1月前左侧睾丸突发疼痛伴肿胀,服用止痛药后缓解,目前仍肿胀疼痛,无发热、恶心、呕吐;入院后体检示左侧睾丸明显增大,压痛阳性,右侧睾丸正常,血检及尿检均正常。B超检查示:左侧睾丸血供减少。核素阴囊显像示:患者血流灌注相左侧睾丸血流灌注减低,静态血池相示左侧睾丸放射性缺损呈“晕圈样”表现,诊断为左侧睾丸缺血(图1)。临床诊断为急性左侧睾丸扭转,经手术结果证实为左侧睾丸扭转并坏死。病理检验报告示:左侧睾丸及附睾出血性梗死,输精管出血性梗死。讨论急性睾丸蒂扭转是泌尿外科常见的一种急症,其主要的治疗方法是急…     

组织谐波显像诊断肝脏病变的临床应用

目的：探讨组织谐波显像对肝脏病变的诊断价值。方法：对比分析56个肝脏病灶的基波显像和组织谐波显像结果。结果：组织谐波显像对病灶的边界和内部回声等状况的显示均明显优于基波显像,对囊性病变尤其明显。结论：组织谐波显像能明显改善图像质量,提高诊断准确性。     

Integrating anatomical and functional imaging for the assessment of coronary artery disease

Coronary artery disease (CAD) is a leading cause of morbidity and mortality. Invasive cardiac angiography with fractional flow reserve measurement allows for the anatomical and functional assessment of CAD. Given the invasive nature of invasive cardiac angiography and the risks of procedure-related complications, research has focused upon noninvasive methods for anatomical and functional measures of CAD. As such, there is growing interest in the development of hybrid imaging because it may provide incremental diagnostic information over each imaging modality alone. We will provide an overview of the evidence to date on the anatomical and functional stratification of CAD and current hybrid techniques.     

移植细胞的影像学示踪

细胞治疗、基因治疗已逐渐成为现代医学治疗的一类重要方法。随着分子影像学的提出,能通过活体检测移植后的细胞,方法主要有磁共振成像、核医学成像、光学成像。     

磁共振扩散峰度成像在人体肾脏的应用

目的探讨磁共振扩散峰度成像(diffusion kurtosis imaging,DKI)在人体肾脏应用的可行性。材料与方法收集2016年3月至2017年2月在我院招募的健康男性志愿者35例,最终纳入30例。采用3.0 T MR进行双侧肾脏冠状位扫描,扫描序列包括:T1WI、T2WI与DKI序列;DKI采用三个不同b值(0、500s/mm2、1000 s/mm2)和30个扩散敏感梯度方向。采用配对t检验对肾皮质、髓质DKI参数进行组间比较。结果正常人左、右两侧肾皮质、髓质DKI均无统计学差异(P>0.05)。正常人肾脏皮质峰度参数值MK值、Ka值及Kr值均高于髓质(P<0.05);皮质的扩散参数FA值、Da值明显低于髓质,MD值、Dr值高于髓质(P<0.05)。结论肾脏的DKI成像不仅能够反映肾皮质、髓质水分子扩散状态差异,而且其特有的峰度参数值还能够提供更多关于肾皮质、髓质微结构的信息。     

磁共振q-空间扩散成像的初步研究

目的探讨q-空间成像在1.5T 临床用设备上的可行性.方法对12名成年健康志愿者分别用不同的q值进行头部扩散张量成像,通过傅立叶变换得到水分子的位移分布.结果通过对所有被试的平均,能够获得水分子的扩散位移轮廓分布.结论使用q-空间成像可以提供活体内的水分子扩散的定量信息,具有潜在的应用价值.     

心脏纵向弛豫时间（T1）成像技术及其临床应用

纵向弛豫时间成像(T1 Mapping)技术能定量显示心肌组织的T1值,从而准确评价多种心肌病变的心肌组织特征。T1 Mapping现在已有多种采集技术,其中初始T1值可重复性高,能反映心肌纤维化,通过测量初始T1值与增强后T1值还能显示心肌弥漫性病变。作者就T1 Mapping技术及其临床应用进行综述。