The invention relates to a catadioptric medical imaging system (1), in particular a surgical microscope (2). During surgery, it may be necessary to gain more information about a surgical cavity (6), in particular the type of tissue (29) at the inside walls (4) of the surgical cavity (6). To solve this problem, the catadioptric medical imaging system (1) according to the invention comprises a camera device (8) and a convex catoptric mirror (20) adapted to be inserted into the surgical cavity (6). The catoptric mirror (20) is mounted on an arm (22) and spaced apart from the camera device (8).