From the case:
Koala in sphenoid sinus
{"current_user":null,"step_through_annotations":true,"access":{"can_edit":false,"can_download":true,"can_toggle_annotations":true,"can_feature":false,"can_examine_pipeline_reports":false,"can_pin":false},"extraPropsURL":"/studies/34277/annotated_viewer_json?lang=us"}
Photo credit: "Cutest Koala" by Eric Veland (original file here)
Case Discussion
The human brain has an amazing tendency to take vague visual stimuli (such as mucous in the sphenoid sinus) and to perceive them as recognisable objects or beings (such as a koala). This phenomenon is known as paredolia and there is probably not a radiologist alive who has not experienced it at some time or other whilst looking at medical images. This is certainly the cutest example I've ever seen. Radiopaedia has a growing collection of such cases on our Rorschach radiology page.