Bones of the Past (Video)

A 44-year-old woman presented two sequential episodes of painful 6th nerve palsy unilateral that alternated sides. Although MRI was initially considered unrevealing, a second radiologic opinion drew attention to gradually progressing changes in the clivus that in retrospect had been present on surveillance scans but not noted for several years. CT-PET showed clivus fibrosis and abnormal adjacent soft tissue, and the clivus was hypermetabolic. A diagnosis of Nelson syndrome was suspected based on the imaging findings and elevated ACTH, and this was confirmed with transsphenoidal biopsy. Nelson's syndrome was previously seen in about 8-47% of people that undergo bilateral andrenalectomy for Cushing's disease, but has become a rare disease with newer treatment protocols .1 Neuro-ophthalmic presentations of Nelson syndrome are extremely rare. A patient with bilateral oculomotor palsy has been reported, and another case of painful diplopia and sixth nerve palsies in a patient who presented with pituitary adenoma apoplexy and subarachnoid hemorrhage.2,3 We are not aware of a single report of Nelson syndrome presenting with abducens palsy because of tumor growth within the clivus for several years, with no concurrent growth in the sella or cavernous sinus.