A Case of Giant Pituitary Adenoma Associated with a Postoperative Mental Disorder That Ultimately Resulted in Bilateral Blindness

PURPOSE: To report the case of a patient with adrenocorticotropic hormone (ACTH)-producing pituitary adenoma who developed a mental disorder after initial surgery that kept him from undergoing scheduled follow-up visits and who ultimately had a giant recurrent tumor that resulted in blindness. CASE REPORT: A 37-year-old male presented with the primary complaint of decreased visual acuity (VA) in both eyes and visual field defects. Visual field examination revealed bitemporal hemianopia. Magnetic resonance imaging (MRI) showed a pituitary tumor of approximately 4 cm in diameter extending from the intrasellar region to the sphenoid sinus and the suprasellar region. Transnasal transsphenoidal surgery was performed. Immunostaining of tumor tissue collected intraoperatively showed ACTH-positive cells, thus leading to the diagnosis of ACTH-producing pituitary adenoma. Postoperatively, the patient reportedly developed mental disorder that possibly interfered with scheduled appointments or continuous follow-up visits for many years, so we had no postoperative data about the vision/visual filed. Seven years later, he presented with markedly decreased VA (i.e., no light perception) in both eyes. Fundus examination showed bilateral marked optic disc atrophy. MRI showed a larger than 8-cm diameter giant recurrent pituitary adenoma in the suprasellar region, for which craniotomy was performed for partial tumor resection. Preoperatively, his blood cortisol level was low, and the lesion was deemed a nonfunctioning pituitary adenoma. Postoperatively, no significant complications occurred, yet his VA was no light perception OD and light perception OS. CONCLUSIONS: Clinicians should be aware that patients with ACTH-producing pituitary adenomas may develop a mental disorder following surgery and possibly be unable to undergo scheduled follow-up, thus illustrating the importance of establishing an adequate patient follow-up system.