Optimal contrast enhancement liquid for dynamic MRI of swallowing

Several dynamic magnetic resonance imaging (MRI) techniques to observe swallowing and their parameters have been reported. Although these studies used several contrast enhancement liquids, no studies were conducted to investigate the most suitable liquids. The purpose of this study was to identify the optimal contrast enhancement liquid for dynamic MRI of swallowing. MRI was performed using a new sequence consisting of true fast imaging with steady-state precession, generalised auto-calibrating partially parallel acquisition and a keyhole imaging technique. Seven liquids were studied, including pure distilled water, distilled water with thickener at 10, 20 and 30 mg mL(-1) concentrations and oral MRI contrast medium at 1, 2 or 3 mg mL(-1) . Distilled water showed the highest signal intensity. There were statistically significant differences among the following contrast media: distilled water with thickener at 20 mg mL(-1) and the oral MRI contrast medium at 2 mg mL(-1) and 1 mg mL(-1) . It can be concluded that the optimal liquid for dynamic MRI of swallowing is a water-based substance that allows variations in viscosity.