Fig. 45. Dysthyroid optic neuropathy. A. Central nerve fiber bundle defects. An arcuate pattern in the left field mimics glaucoma. The patient was a 53-year-old woman with moderate bilateral proptosis and lid retraction, who noted slowly progressive loss of color appreciation. Visual defects cleared rapidly and completely on large doses of systemic corticosteroids. Discs were at all times normal. B. A 57-year-old woman with moderate congestive ophthalmopathy experienced diminution of vision from 20/25 OU to 20/100 OU in 6 weeks and 4/200 to 5/200 by 10 weeks. The right disc was swollen and elevated with several hemorrhages; the left disc was normal. Massive doses of systemic steroids resulted in slow improvement to 20/200 and 20/400. LE, left eye; RE, right eye.