A 61-year-old man was admitted with postoperative progressive bilateral visu al loss following a parasagittal meningioma resection. No risk factor predisposi ng to an ischemic optic neuropathy was present and routine radiologic examinatio ns did not reveal any pathology of the central or peripheral visual pathways. Mu cin-positive adenocarcinoma cells were detected in the cytological examination and orbital MRI revealed metastatic infiltration of the optic chiasm and optic n erves. The primary site of the malignancy could not be established. A 61-year-old man was admitted with postoperative progressive bilateral visu al loss following a parasagittal meningioma resection. No risk factor predisposi ng to an ischemic optic neuropathy was present and routine radiologic examinatio ns did not reveal any pathology of the central or peripheral visual pathways. Mu cin-positive adenocarcinoma cells were detected in the cytological examination and orbital MRI revealed metastatic infiltration of the optic chiasm and optic nerves. The primary site of the malignancy could not be established.