The present invention relates to a contrast medium composition (formulation) comprising a highly concentrated contrast agent for use in an imaging method. The contrast medium composition comprises an aqueous contrast agent selected from the group consisting of iopentol, iotrolan, iohexol, ioversol, ioxilan, iodixanol and iobitridol in an amount of 360 mgl/mL to 450 mgI/mL.The contrast medium composition according to the present invention, which comprises iodine working as a contrast agent in a higher concentration than the concentration used before, shows higher contrast enhancement effect in both of arterial phase and portal phase when used for liver CT than a composition comprising the contrast medium in a concentration used before. Accordingly, images having excellent resolution and discrimination can be obtained.
