Liquid management in an ophthalmological device

An ophthalmological device which provides suction flushing with an aspiration function and an infusion function, comprising:

• one or more connectors configured to couple with a surgical instrument outside the ophthalmological device;
• an aspiration conveyor device for motor-driven discharge of liquid from the surgical instrument into a waste container, based on peristaltic pumping or vacuum suction;
• an infusion conveyor device for motor-driven feeding of an infusion medium from an infusion container via an infusion connection and a line to the surgical instrument, wherein the infusion conveyor device is designed as a peristaltic pump for active infusion volume delivery of the infusion medium with a known delivery volume to the surgical instrument;
• a pressure measuring device with a pressure or force sensor in the ophthalmological device, wherein the pressure measuring device is formed between the infusion conveyor device and the surgical instrument, and is configured to determine an infusion pressure of the infusion medium in the ophthalmological device;
• an interchangeable cassette removably disposed in the ophthalmological device, wherein regions of the infusion conveyor device that come into contact with the infusion medium together with regions of the aspiration conveyor device that come into contact with the liquid are formed in the interchangeable cassette;
• and
• a controller configured to regulate the infusion volume delivery based on the infusion pressure and a pressure drop in the line to the surgical instrument,
• wherein the pressure drop in the line to the surgical instrument is at least partially compensated with a pressure increase in the infusion volume delivery,
• wherein the pressure measuring device comprises a flexible membrane in the interchangeable cassette, and
• wherein the pressure or force sensor is disposed outside the interchangeable cassette and in contact with the flexible membrane.