Such cameras (sold by Nikon [1]) are routinely used on high-end microscopes. They usually have a smaller resolution though - 1024x1024 is pretty common. There are a number of technologies used in scientific microscopy that work well for night-time photography, but most are just too expensive. Electron multiplying CCDs, chilled CMOS sensors, etc. They end up being one of the more expensive parts to a half-million dollar scope though.
[1] https://www.nikoninstruments.com/Products/Cameras/Camera-Hea...