Aspergillus parasellar abscess mimicking radiation-induced neuropathy: Case report

BACKGROUND: Transsphenoidal surgery is a safe procedure for treatment of pituitary adenomas. However, several complications, including post-surgical infection, are known. We describe a case of Aspergillus parasellar abscess that presented with cranial neuropathies following transsphenoidal surgery and radiosurgery. We initially diagnosed the case as radiation-induced neuropathies, which delayed the detection of Aspergillus. CASE DESCRIPTION: A 55-year-old man underwent transsphenoidal surgery for a pituitary adenoma that presented with pituitary apoplexy. Dexamethasone had been continuously administered for hypocortisolism probably caused by pituitary apoplexy. Four years later, radiosurgery was performed for a relapse in the right cavernous sinus. Another 4 years later, he developed painful right ophthalmoplegia, right ptosis, and bilateral visual impairment, successively. We initially suspected that the painful ophthalmoplegia and ptosis were because of radiation-induced cranial neuropathies; however, results of magnetic resonance (MR) imaging and his clinical course were not consistent with those of radiation-induced neuropathies. Therefore, we performed exploratory surgery that revealed a subdural abscess on the planum sphenoidale. Culture of a specimen grew Aspergillus fumigatus. CONCLUSION: Intracranial fungal abscess is a fatal complication unless it is treated early. It is thus important to consider the possibility of parasellar infection and differentiate it from radiation-induced cranial neuropathies when a patient presents with cranial neuropathies after transsphenoidal surgery and radiosurgery.