低温塩化マンガン四水和物内用液によるMRCP画質改善の効果

摘要

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 T_1 and T_2 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℃, 15℃, 23℃, 35℃， and 40℃). As a result, the T_1 and T_2 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℃) and low temperature (10℃) 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.%Magnetic resonance cholangiopancreatography (MRCP)は1991年にWallner,1992年にMorimotoらにより最初に報告され，当初は主に胆道系にのみ応用されておりMR cholangiographyの呼称が使われていた.その後分解能が向上して膵管が安定して描出されるようになり，endoscopic retrograde cholangiopancreatography(ERCP)にちなんでMRCPの用語が用いられるようになり，非侵襲的な胆管膵管撮像として広く普及するに至った.