A laser treatment head guides a laser beam to a target area within a body cavity and includes a laser output element having a deflection element. The laser output element with deflection element is rotatable relative to a guide element about an axis. First and second thread elements mutually engage to cause the deflection element to perform a combined axial and rotational movement relative to the guide element. A control unit and the laser treatment head are configured such that the target area is irradiated by individual pulses (p) in a helical pattern of irradiation spots over a section of the circumference of the body cavity. The control unit is further configured such that reference locations (X) on the target area are irradiated by an individual pulse number (N) of subsequent pulses (p), thereby heating the mucosa tissue within the target area to a predetermined temperature.
