If an adult has a swollen-looking optic nerve that doesn’t go away, certain imaging tests like eye ultrasounds, CT scans, and special eye photos can help confirm whether they have small calcium-like deposits called optic disc drusen.

What we've found so far is that certain imaging tests may help identify optic disc drusen in adults who have persistent optic disc elevation [1]. The evidence we've reviewed leans toward the usefulness of B-scan ultrasound, A-scan ultrasound, CT scans, and optic disc autofluorescence in detecting these deposits when the optic nerve appears swollen over time [1]. Our analysis of the available research shows that when an adult’s optic disc remains elevated and looks similar to swelling but doesn’t improve, imaging tools can provide additional insight [1]. B-scan and A-scan ultrasounds use sound waves to create images of the eye structures and may reveal calcium-like deposits within the optic nerve head [1]. CT scans, which use X-rays to produce cross-sectional images, can also detect calcifications associated with optic disc drusen [1]. Additionally, optic disc autofluorescence—a non-invasive imaging technique that captures light emitted from the optic nerve—may help visualize these deposits based on their natural glow under specific lighting [1]. We’ve reviewed 20.0 assertions supporting the use of these imaging methods in this context, with no studies or claims refuting it [1]. However, we emphasize that our current analysis reflects what has been reported so far—not a final conclusion. We cannot say how accurate or reliable these tests are compared to one another, nor do we have data on how often they lead to changes in patient outcomes. Because optic disc drusen can mimic more serious conditions like papilledema, being able to distinguish them matters for proper care. Still, we don’t yet have enough evidence to say which test is best or under exactly what circumstances each should be used. Practical takeaway: If your optic nerve looks swollen but hasn’t changed over time, your eye doctor might use special imaging tests to check for buried calcium deposits—common in optic disc drusen—and rule out other causes.