Abstract: A method for automatically detecting a clinically relevant leak and/or inadequate closure following a medical procedure, in a hollow organ residing in the interior volume of a body cavity. The test method includes the steps of: injecting, via an adapted injection element, a specific test gas or a gas mixture containing at least one test gas, into the organ, analyzing the gas mixture and measuring the test gas concentration in the interior volume of the body cavity via an adapted detection element and at least during a measurement window, evaluating the likelihood of the presence of a leak and its degree of severity, by comparing stored data and real-time data with each other. The pressure difference between the interior of the hollow organ(s) and the interior volume of the body cavity is controlled or mastered at least at a given moment during at least one measurement window.