Nanoparticulate diagnostic diatrizoxy ester X-ray contrast agents for blood pool and lymphatic system imaging

This invention relates to methods of x-ray diagnostic imaging the blood pool and/or lymph system of a mammal comprising administering a contrast effective amount of a particulate iodinated aroyloxy ester contrast agent having the structure: alkyl, fluoroalkyl, cycloalkyl, aryl, aralkyl, alkoxyalkyl or acetamidoalkyl; R2, R3 and R4 are independently H, alkyl, fluoroalkyl, alkoxy, aryloxy, halogen, hydroxy, acylamino, acetamidoalkyl, -COO-alkyl, -COO-aryl, -COO-aralkyl, cyano, sulfonyl, carboxamido or sulfonamido; R5 is H, alkyl, fluoroalkyl, halogen, hydroxy, acylamino, acetamidoalkyl, cyano, sulfonyl, carboxamido or sulfonamido; R6 and R7 are independently alkyl, cycloalkyl, aryl or aralkyl; and R8 and R9 are independently H or -COR6. This invention further relates to novel iodinated aroyloxy ester contrast agents having the above structure wherein n is an integer from 5 to 20, to x-ray contrast compositions comprising such agents, and to methods of x-ray diagnostic imaging utilizing such agents.