A device (10) of and a method for obtaining thermal images of a living mammal body section. The device comprises a thermal energy storage surface structure (18) for contacting the body section. In a calibration mode of operation, the thermal energy storage surface structure (18) is brought at a reference temperature by transferring thermal energy to the thermal energy storage surface structure (18) from a thermal energy transfer module (21) that is controlled by a control circuit (30) for restraining thermal energy transfer by the thermal energy transfer module (21) in the presence of the body section (35) at the thermal energy storage surface structure (18). In a registration mode of operation, by a thermal sensor (19), thermal images reflecting thermal energy storage over at least a portion of the thermal energy storage surface structure (18) are obtained, with the body section contacting the thermal energy storage surface structure (18). From a series of time consecutive thermal images obtained, a region of interest is determined, based on storage of thermal energy by the thermal energy storage surface structure (18).
