A first controller synthesizes image output of a CCU and a cursor created based on trigger information from a second controller, following location information. The synthesized image is displayed on a first monitor, so an endoscope image and a cursor image which moves synchronously with the cursor image on a display device can be simultaneously viewed at the surgery room side on a single monitor, and accordingly, the problem of the working space inside the surgery room becoming crowded due to providing multiple observation monitors in the surgery room does not occur.