A poor pug was called the ''cutest and most terrifying thing'' after its MRI scan.

Bizarre on Female First

Bizarre on Female First

Comedian Andy Richter shared an image of his friend's dog during a scan - which caused ''happy nightmares'' for Twitter users with its bulging eyes.

He simply tweeted: ''My friend's pug went to the vet.''

And now a vet suggested the scan is ''pretty odd-looking'' and warned of the dangers of human breeding.

Dr. Rory Cowlam said: ''Their faces have been shortened due to intensive breeding by humans, unfortunately.

''We have, through human selection, bred them to look more like a human baby because we find that cute, but unfortunately that cute look is not very good for the animal.''

Users didn't hold back with their comments, as one wrote: ''That is simultaneously the cutest and most terrifying thing I have seen in my entire life. Thank you for the happy nightmares this image will bring me tonight.''

Another added: ''Amazing. Pugs may be the only creature to look exactly the same in X-Ray as in visible light.''