The invention relates to a medical imaging device which includes a central control unit and a number of peripheral devices connected to the central control unit, one or more of the peripheral devices being provided with separate emergency control means which are arranged to allow the peripheral devices in question to function independently from the central control unit, the medical imaging device also being provided with an emergency control unit for controlling the emergency control means.The invention also relates to a method for use of the medical imaging device according to the invention in a safety critical environment and to a computer program for carrying out the method according to the invention.