an apparatus for the automatic performance of diagnostic and / or therapeutic actions in body cavities is provided with a base control unit , which is to be arranged extracorporally , and with a catheter - type actuator , which is coupled therewith and which is insertable in the corresponding body cavity and which , in the vicinity of its distal end , is provided with a diagnostically active detection equipment and / or a therapeutically active treatment equipment , and which , at least in the vicinity of its distal end , is provided with an actuation mechanism , which is triggered by the base control unit , for advance and / or twist and turn control of the actuator .