Images of Memorable Cases: Case 94 This 25-year-old Caucasian woman complained of progressive headaches, visual difficulties, and darkening of her skin during the preceding six months. Three years earlier, she had undergone bilateral adrenalectomy for treatment of Cushing’s disease. 94. Nelson’s syndrome Development of an ACTH-producing, rapidly growing, and often invasive pituitary tumor after bilateral adrenalectomy for Cushing’s disease. The clinical manifestations are headache, visual field defects, external ophthalmoplegias, and ACTH-induced hyperpigmentation similar to that of Addison’s disease. The patient shown had generalized hyperpigmentation of her skin and mucosal surfaces, a large pituitary mass, bitemporal hemianopia, and palsies of the right 3rd and 6th cranial nerves. After transphenoidal resection of most of her pituitary tumor, coupled with postoperative radiation therapy, her headaches resolved and her vision improved, but her ophthalmoplegias and hyperpigmentation did not change.