Manganese chloride tetrahydrate (MCT) is one of the oral negative contrast agents which is indispensable for imaging of magnetic resonance cholangiopancreatography (MRCP). In this study, improvement of the image quality of MRCP by using low-temperature MCT is verified. All MR imagings were performed using 1.5 T scanner. The T1 and T2 values of the different temperature MCTs were measured in the phantom study. Different concentrations of MCT-doped water (30%, 50%, 70%, and 90%) were measured at several temperature conditions (10°C, 15°C, 23°C, 35°C, and 40°C). As a result, the T1 and T2 values became larger with a temperature rise. It was more remarkable in low-concentration MCT. Then, 17 healthy subjects were scanned two times with different temperatures of MCT. The MCT of the normal temperature (23°C) and low temperature (10°C) were taken at consecutive 2 days. The contrast between the stomach and the spleen were significantly higher in 2D half Fourier acquisition single shot turbo spin echo (HASTE) images by use of the low-temperature MCT. The contrast between the common bile duct and the adjacent background were significantly higher in the source images of 3D MRCP by use of the low temperature MCT. In addition, 76% of subjects answered in the questionnaire that the low temperature MCT is easier to drink. The low temperature MCT improves the image quality of MRCP and contributes to performing noninvasive examination.
The purpose of this study is to develop a new system to get and share some data of a patient which are required for a radiological examination not using an electronic medical chart or a radiological information system (RIS), and also to demonstrate that this system is operated on cloud technology. I used Java Enterprise Edition (Java EE) as a programing language and MySQL as a server software, and I used two laptops as hardware for client computer and server computer. For cloud computing, I hired a server of Google App Engine for Java (GAE). As a result, I could get some data of the patient required at his/her examination instantly using this system. This system also helps to improve the efficiency of examination. For example, it has been useful when I want to decide radiographic condition or to create CT images such as multi-planar reconstruction (MPR) or volume rendering (VR). When it comes to cloud computing, the GAE was used experimentally due to some legal restrictions. From the above points it is clear that this system has played an important role in radiological examinations, but there has been still few things which I have to resolve for cloud computing.
It is considered that the enhancement of chemical shift and the elevation of signal-to-noise ratio (SNR) induced by high magnetic fields are useful for the evaluation of metabolism using magnetic resonance spectroscopy (MRS). However, the reduction of the localization in MRS seems to be caused by the decreased homogeneity of radio frequency (RF) pulses, especially in chemical shift imaging (CSI). To search the influence of B1 shim mode and the significance of adiabatic pulses, we have examined the changes of RF homogeneity using 3 T magnetic resonance imaging (MRI) with the water phantom and the metabolites phantom (containing acetate and lactate) in CSI. The RF homogeneity and chemical shift artifact were obviously improved using the adiabatic pulses. Improvement of the homogeneity of RF pulses was observed when B1 shim was used. These results suggest the usefulness of CSI using adiabatic pulses and B1 shim when small amount of metabolites of target is measured in MRS.