Use of tetra azacycle complexes as x-ray diagnostic agents for the liver and gallbladder

In a method of performing computer tomography of the liver and the biliary tracts, the improvement wherein a contrast agent is administered and said contrast agent is a metal complex is of formula V ##STR38## wherein X is, in each case, independently of one another, hydrogen or a metal ion equivalent of an element of the atomic numbers 39-42, 44-51 or 56-83,

• n is 0, 1 or2,
• R.sup.1 is, in each case, of one another, hydrogen or a radical of formula Ia independently ##STR39## m and p are each independently 0 or 1, wherein at least one of m or p is 1, and if either m or p is equal to zero, two or more heteroatoms are not directly connected to one another,
• R.sup.2 is, in each case, independently of one another, hydrogen or a branched or unbranched, saturated or unsaturated C.sub.1 -C.sub.6 hydrocarbon radical, and
• L.sup.1, L.sup.2 and L.sup.3 are, in each case, independently of one another, a direct bond, an oxygen atom, a sulfur atom, --N(H), --N(R.sup.2), a C.sub.1 -C.sub.10 alkylene chain, or a C.sub.1 -C.sub.10 alkylene chain interrupted by an oxygen carbon atom, a sulfur atom, --N(H) or N(R.sup.2);
• wherein the symbol ##STR40## is a saturated, unsaturated or aromatic C.sub.6 ring which is substituted n-fold by R.sup.1,
• wherein free carboxyl groups that are not used for complexing can optionally be present as salts of physiologically compatible cations or as amides of the formula ##STR41## at least one of the R.sup.1 groups is a radical of formula Ia.

In a method of performing computer tomography of the liver and the biliary tracts, the improvement wherein a contrast agent is administered and said contrast agent is a metal complex is of formula IV ##STR42## wherein X is, in each case, independently of one another, hydrogen or a metal ion equivalent of an element of the atomic numbers 39-42, 44-51 or 56-83,

• R.sup.1 is, in each case, independently of one another, hydrogen, or a radical of formula Ia ##STR43## m and p are each independently 0 or 1, wherein at least one of m or p is 1, and if either m or p is equal to zero, two or more heteroatoms are not directly connected to one another,
• R.sup.2 is, in each case, independently of one another, hydrogen or a branched or unbranched, saturated or unsaturated C.sub.1 -C.sub.6 hydrocarbon radical, and
• L.sup.1, L.sup.2 and L.sup.3 are, in each case, independently of one another, a direct bond, an oxygen atom, a sulfur atom, --N(H), --N(R.sup.2), a C.sub.1 -C.sub.10 alkylene chain, or a C.sub.1 -C.sub.10 alkylene chain interrupted by an oxygen atom, a sulfur atom, --N(H) or --N(R.sup.2);
• wherein free carboxyl groups that are not used for complexing can optionally be present as salts of physiologically compatible cations or as amides of the formula ##STR44## at least one of the R.sup.1 groups is a radical of formula Ia.