<Tr> <Td> Non-ionic </Td> <Td> ioxilan (Oxilan 350) </Td> <Td> Monomer </Td> <Td> 350 mgI / ml </Td> <Td> 695 </Td> <Td> Low </Td> </Tr> <Tr> <Td> Non-ionic </Td> <Td> iopromide (Ultravist 370) </Td> <Td> Monomer </Td> <Td> 370 mgI / ml </Td> <Td> 774 </Td> <Td> Low </Td> </Tr> <Tr> <Td> Non-ionic </Td> <Td> iodixanol (Visipaque 320) </Td> <Td> Dimer </Td> <Td> 320 mgI / ml </Td> <Td> 290 </Td> <Td> Low </Td> </Tr> <Tr> <Td> Non-ionic </Td> <Td> ioversol </Td> <Td> </Td> <Td> </Td> <Td> </Td> <Td> </Td> </Tr>

What is the difference between ionic and nonionic contrast media