Gadobutrol at different injection rates for dynamic supra-aortic imaging by contrast-enhanced magnetic resonance angiography

The aim of this study was to compare differences in imaging quality at different injection rates of gadobutrol(Gadovist? 1.0M) for dynamic supra-aortic imaging by contrast-enhanced magnetic resonance angiography(CEM RA). In 6 healthy volunteers,dynamic CEM RA examinations were performed twice at a 7 d interval with a gadobutrol dose of 0.1 mmol given to 1 kg body mass. For the two examinations,the contrast medium was injected at rates of 1.5 mL/s and 2.0 mL/s,followed by 20 mL normal saline injected at the same rate. Using a GE Signa 3.0T M R apparatus and the time-resolved imaging of contrast kinetics(TRICKS) technique,scanning was performed continuously for 15 phases at a time resolution of about 2.4 s. Vascular reconstruction was undertaken by multiplane reconstruction and maximum intensity projection techniques. Two radiologists experienced in CEM RA diagnosis subjectively evaluated the contrast effect,vascular detail,and pseudo-shadow of all images,and graded them via a 5-point scale. With the two drug injection rates,the image quality,peak signal-to-noise ratio(SNR) and contrast-to-noise ratio(CNR) were compared for imaging of the infra-aortic arch,brachiocephalic trunk,subclavian artery(left/right),common carotid artery(left/right),internal carotid artery(left/right),and external carotid artery(left/right). Characteristics of the time-signal-intensity(T-S-I) curves were also analyzed at the two injection rates. All studies were performed successfully,without any complications. There was good image quality with both gadobutrol injection rates of 1.5 mL/s and 2.0 mL/s,and subjective scores for image quality,SNR and CNR were not significantly different between the two rates(P 0.05). The time-to-peak(TTP) from the hand dorsal vein injection site to the carotid artery ranged from 16.0 s to 27.1 s(mean 21.7 s ±3.4 s) in the 6 subjects,and was also not significantly different between the two drug injection rates(P 0.05). We conclude that dynamic CEM RA examination of the supra-aortic arch with gadobutrol injection at a rate of 1.5 mL/s was feasible,and satisfactorily reflected vascular shape and dynamic blood flow information.     

Electron paramagnetic resonance imaging

In this part we shall outline the challenges one faces while developing time-domain radiofrequency (RF) EPR imaging spectrometer for in vivo studies. Time-domain or FT-EPR is quite a different animal compared to the CW modality. The evolution of FT-EPR instrumentation at the National Cancer Institute, NIH, USA and representative examples of application in cancer research are outlined in this article.     

The value of neurosurgical and intraoperative magnetic resonance imaging and diffusion tensor imaging tractography in clinically integrated neuroanatomy modules: A cross‐sectional study

Neuroanatomy is considered to be one of the most difficult anatomical subjects for students. To provide motivation and improve learning outcomes in this area, clinical cases and neurosurgical images from diffusion tensor imaging (DTI) tractographies produced using an intraoperative magnetic resonance imaging apparatus (MRI/DTI) were presented and discussed during integrated second‐year neuroanatomy, neuroradiology, and neurosurgery lectures over the 2008–2011 period. Anonymous questionnaires, evaluated according to the Likert scale, demonstrated that students appreciated this teaching procedure. Academic performance (examination grades for neuroanatomy) of the students who attended all integrated lectures of neuroanatomy, was slightly though significantly higher compared to that of students who attended these lectures only occasionally or not at all (P=0.04). Significantly better results were obtained during the national progress test (focusing on morphology) by students who attended the MRI/DTI‐assisted lectures, compared to those who did so only in part or not at all, compared to the average student participating in the national test. These results were obtained by students attending the second, third and, in particular, the fourth year (P≤0.0001) courses during the three academic years mentioned earlier. This integrated neuroanatomy model can positively direct students in the direction of their future professional careers without any extra expense to the university. In conclusion, interactive learning tools, such as lectures integrated with intraoperative MRI/DTI images, motivate students to study and enhance their neuroanatomy education. Anat Sci Educ 6: 294–306. © 2013 American Association of Anatomists.     

核磁共振波谱检测平台建设

针对核磁共振波谱检测平台,详细叙述了核磁共振波谱仪的组成及特点,根据探头类型,介绍了用该中心的核磁共振波谱仪可以进行的实验项目,同时对测试要求做了详尽的论述.     

影响磁共振的几个外部因素

目的:探讨影响磁共振成像设备性能的外部因素。方法:根据磁共振成像设备的特点,分别分析了对磁共振成像有影响的外部因素,包括设备周边环境、射频屏蔽、空调、冷水机等。结果:外部因素会影响磁共振成像设备性能的发挥,会影响图像的质量,会导致设备故障。结论:处理好对磁共振成像设备有影响的外部因素,是有效发挥磁共振成像设备性能、获得高质量图像的保证。     

光磁共振实验中数据处理

大学物理实验室中测量铷的朗德g 因数时,测得多个共振频率.这些频率是在扫场和地磁场下作用的结果.该文提出的数据处理方法可以消除地磁场和扫场的干扰,得到了很好的结果.