I had a patient who I was following for a couple of years as a glaucoma suspect- she a had slightly elevated IOP’s in the low 20’s with thin corneas and the visual field showed a classic arcuate. The discs had mild cupping, and in hindsight, should have been a red flag that something was not quite right, as the cupping did not seem to correlate with the field, especially since the field defect was unilateral. I put her on Timoptic and her visual field remained perfectly stable. Then, for unrelated reasons, she needed a head CT, and sure enough- the radiologist found optic nerve head drusen. Now it all made more sense- she never had glaucoma at all. I took her off the Timoptic and she is doing fine. I now try to have a low threshold for getting a CT scan of the discs when I see unilateral glaucoma and the discs just don’t seem to jibe with the field, even when there are plenty of risk factors like high IOP and thin corneas.