Papilledema and the Crescent Sign

  What’s abnormal in this image?   Here’s a hint.  Here is an example of normal.   When evaluating for possible elevation in intracranial pressure, it has been shown that optic nerve sheath diameter (ONSD) measurements correlate with elevated intracranial pressures.(1,2)  The optic nerve attaches to the globe posteriorly and is wrapped in a sheath thatRead more