Abstract
To evaluate the image quality of the urinary tract using oral administration of a combination of both water and a negative gastrointestinal contrast agent, Bothdel. The study was divided into two parts: the phantom study and the healthy volunteers study. The imaging sequences used were the rapid acquisition with relaxation enhancement (RARE) and the half-Fourier acquisition single-shot turbo spin-echo (HASTE) techniques. Magnetic resonance Urography (MRU) was performed in 13 healthy volunteers using the RARE imaging sequences. After collection of the pre-contrast images, post-contrast MRU was obtained 30 min and 60 min after the oral administration of the contrast agent. Image assessment was based on the contrast effect, the image effect, and the opacification score. Statistical analysis was performed using the Wilcoxon signed-rank test. The signal intensity using 100%-12.5% Bothdel was no different to the background noise using the RARE sequence. At concentrations below 12.5%, there were statistically significant improvements in the contrast, the image effect, and the opacification score between pre-and post-contrast images. No significant difference was observed between the 30 min and 60 min post-contrast images. In contrast, the effect and pre-contrast images were graded as poor in seven cases, whereas no post-contrast images were graded as poor. There was a particularly significant improvement in the opacification score with the distal ureter being the most difficult segment to opacify. Oral administration of both water and Bothdel effectively removed the bowel signal and improved visualization of the urinary tract.
