Method for adjusting a fill level of a liquid balloon of a medical device, and medical device comprising a liquid balloon for forming artificial sphincters

A method for setting a first fill level of a liquid balloon with a first filling pressure and a differently filled second fill level of the liquid balloon with a second filling pressure, the method comprising:

• for pumping liquid into the liquid balloon and for pumping liquid out of the liquid balloon, changing a volume of a liquid-filled receiving space of a pump unit which is connected to the liquid balloon via a hose by moving an actuating part of the pump unit using an electric motor which is powered by a battery;
• for setting the second fill level of the liquid balloon starting from the first fill level of the liquid balloon by a control unit which controls the electric motor, carrying out an actuating process of the actuating part including detecting a pressure of the liquid in the receiving space;
• and
• the actuating process comprising travel control of the actuating part for approaching a target position of the actuating part, including detecting a respective position of the actuating part using a travel sensor, and after the travel control, checking whether the pressure of the liquid in the receiving space lies within a permissible filling pressure range around the second filling pressure, and in the event that the pressure of the liquid in the receiving space lies outside the permissible filling pressure range around the second filling pressure, adjusting the position of the actuating part.