Abstract: A system for surgical treatment, in particular endovenous laser treatment, includes a laser device and an application module, wherein the laser device comprises a laser light source having at least one first laser diode element and the application module is optically connectable or connected to the laser light source. The application module is designed as a flexurally flexible catheter having an optical waveguide which comprises an RFID chip with a parameter and/or release coding, wherein the laser device comprises a controlling means with an RFID transmitter and receiver unit for reading from and writing to the RFID chip. The controlling means is configured such that an activation of the laser light source ensues in response to the RFID receiver unit detecting a predetermined parameter and/or release coding, and a timestamp is stored on the RFID chip for the invalidating of the catheter.