Method for production of a medical marker

1. A method for production of a ring-shaped and non-self-supporting medical marker having a wall thicknesses of less than 20 μm and comprising an X-ray-opaque material, wherein the method comprises the following steps:

a) applying a mask with ring patterns formed in registration on two surfaces of a conductive plate-shaped substrate by photolithography;

b) depositing the X-ray-opaque material of the marker in a borehole in the substrate;

c) removing the mask; and

d) eliminating the substrate such that the marker is non-self-supporting,

wherein step a) comprises: i) coating the substrate with a photoresist; ii) exposing parts of the photoresist to light to form the mask; iii) developing the photoresist; and iv) removing non-exposed parts of the photoresist by forming the borehole through the substrate and at least one ring-shaped free space of the mask, such that the substrate lying under the at least one ring-shaped free space is removed, and

wherein step b) comprises: aa) passing a flow of electrolyte through the mask and the borehole; and bb) depositing the X-ray-opaque material from the electrolyte onto a wall of the borehole by galvanic deposition.

2. The method according to claim 1 , wherein step b) includes depositing the X-ray-opaque material on the wall of the borehole and in the at least one free space of the mask.

3. The method according to claim 2 , wherein the at least one free space forms a functional component of the marker.

4. The method according to claim 1 , wherein in step a) iv) the substrate lying under the at least one free space is etched away with an acid and/or is removed with a laser to form the borehole.

5. The method according to claim 1 , wherein in step d), the remaining portions of the substrate are dissolved in an acid.

6. The method according to claim 1 , wherein after step c) and before step d), a catheter is guided through the marker.